Médecins sans frontières (MSF) teams prepare to distribute mosquito nets to protect against mosquito bites during a health fair in vulnerable communities in Anzoátegui state, Venezuela.

Climate change, unplanned urbanization, sprawling cities, and the El Nino effect all converged to make 2024 a “historic” year for dengue transmission. With increased opportunities for Aedes aegypti mosquitoes–the insects that carry dengue– to breed, cases reached a record 12.7 million cases in the WHO’s Americas Region, nearly three times more than in 2023.

This translates to roughly 21,000 severe cases and over 7700 deaths across northern, central and southern regions of the continent.  And more than a third of the severe cases occurred in children, warned Dr Jarbos Barbosa, Pan-American Health Organization (PAHO) Director, in a press conference last week. 

“In countries like Guatemala, 70% of dengue-related deaths have occurred in children,” Barbosa noted. Barbosa’s home country of Brazil accounted for nearly 80% of cases in the Americas, followed by Argentina, Colombia, and Mexico. 88% of deaths from dengue occurred in these four countries.

At the close of this historic dengue season, Pan-American Health Organization (PAHO) leadership discussed reasons for the surge in cases, and the tools to combat next season’s caseload. Of concern is the geographic expansion of dengue-susceptible regions into countries like Argentina, Uruguay, and the United States. “This increase in cases is directly associated with climate events, including droughts, floods, and warmer climates that favour the proliferation of mosquito breeding sites,” said Barbosa. The director also cited population growth, unplanned urbanization, poor living conditions, and inadequate water supply and waste disposal as major drivers of dengue transmission. 

“Despite these challenges, we are not defenseless,” argued Barbosa. Vector surveillance, improved case management, community engagement, and the rollout of dengue vaccines in targeted populations have meant PAHO is optimistic about next year’s season. “We don’t have a crystal ball,” said Dr Sylvian Aldighieri, PAHO director of the Department of Prevention, Control, and Elimination of Transmissible Diseases, referring to 2025 projections. But because 2024 had such high transmission rates, much of the population has now acquired immunity to the most prevalent serotypes, he noted. 

Migrants at risk of dengue and other diseases – gaps in data and health care coverage are challenges

Migrants in Darien Gap Panama
Over half a million migrants passed through the Darien Gap in 2023. “A vulnerable population” according to PAHO, migrants face a host of health challenges.

While dengue is typically characterized as an urban disease–where mosquitoes breed in discarded plastic bottles and sidewalk puddles, the large migrant population moving through central America to southern and central Mexico [Mesoamerica] towards the United States, is also especially vulnerable to infectious diseases.

“This is a big throughway for persons,” noted Dr Thais dos Santos, Regional Advisor on Surveillance and Control of Arboviral Diseases, in response to a Health Policy Watch query. “Dengue surveillance has a long tradition in the region of the America, but as it evolves, we realize that there are some data gaps.” Healthcare facilities do not typically collect information on a patient’s migrant status, meaning there is limited data to understand the burden of dengue in migrants. Dos Santos cautioned, thus, that PAHO has limited data to understand the scope of migrant health statuses, especially with regard to vector-borne diseases.

Dengue is not the only communicable disease of concern for migrants. “We are assisting countries in preventing any reintroduction of malaria that can be spread through the flow of migrants,” said Dr Andrea Vicari, PAHO Head of the Infectious Hazard Management Unit. “It’s a population at risk, living in very vulnerable conditions,” Vicari noted. 

Strengthening migrant health remains a PAHO priority, as record-breaking numbers of asylum-seeking migrants traverse the Darien Gap through Panama. The year 2023 saw more than half a million people transit through Mesoamerica en route to the United States. This population is burdened by a host of health threats, including sexual and gender-based violence, food insecurity, HIV, and malaria. PAHO’s November 2024 migrant health report called for increased access to emergency, maternal, pre and postnatal, and mental health services. 

Oropouche, avian flu emerge as new threats in 2024

PAHO leadership arboviruses
PAHO Arbovirus Panel (From left): Dr Andrea Vicari, Dr Sylvain Aldighieri, Dr Jarbas Barbosa, Dr Thais dos Santos.

While dengue contributed to the largest burden of mosquito-borne diseases, PAHO leadership also brought attention to Oropouche, a rare but increasingly circulating virus in the Americas. The year 2024 saw nearly 12,000 cases, mostly in Brazil, representing a dramatic increase since last year. The virus, an arbovirus like dengue, Zika, and chikungunya, is spread through bites by certain midge mosquitos. Oropouche symptoms are similar to these other arboviruses with fever, rashes, muscle aches, and headaches common. Symptoms typically last 5 to 7 days, but more recently, the virus has been linked to severe fetal outcomes, including congenital abnormalities and death. 

Notably, cases were seen in regions not typically associated with the disease, mirroring dengue’s march into new geographic areas.  Brazil also reported several instances of transmission from mother to child earlier this year, with 8 cases of infant microcephaly and fetal death, causing the US Centers for Disease Prevention and Control (CDC) to issue travel warnings for pregnant women to the affected regions in the country. 

PAHO leadership also provided an updated report on the ongoing H5N1, or avian flu, outbreak in North America. The United States has already reported 58 human cases, mostly poultry and dairy workers, while in Canada a teenager with no known contact with infected birds or cattle also fell ill recently – reviving longstanding concerns about new virus mutations that could facilitate more human-to-human transmission.

“Surveillance, including genomic characterization, is crucial to track the virus across species, understand its evolution and risks to humans, and guide our actions,” said Barbosa. The director argued that intersectoral collaboration with a One Health approach is critical – as this influenza strain has now jumped to dairy cows for the first time, meaning that measures to reduce animal exposures as well as to protect people must be addressed together.

Also among the longstanding WHO recommendations is the pasteurization of milk to contain the public health risk. “The pasteurization of the milk has been described and used for the last 150 years. This is one of the great achievements of the public health sector…with pasteurized milk, we should not have any major issues of transmission of this disease to people,” mentioned Dr Vicari.

“Countries must strengthen their surveillance and continue sharing information. We must work across borders to monitor new cases and support health systems to respond,” emphasized Barbosa.

Image Credits: Matias Delacroix/MSF, PAHO/WHO, PAHO/WHO/David Spitz.

A Mexican study has found that younger people are more vulnerable to heat, possibly because they spend more time working outside.

Some 75% of heat-related deaths occurred amongst people under the age of 35 , and one-third of such deaths were young adults between the ages of 18 to 35, according to a new study on heat mortality in Mexico.

This contradicts previous assumptions that the elderly are the most vulnerable to heat.

“We project, as the climate warms, heat-related deaths are going to go up, and the young will suffer the most,” said R. Daniel Bressler, a PhD candidate in Columbia’s Sustainable Development program and co-lead author of the study, published in Science Advances.

“It’s a surprise. These are physiologically the most robust people in the population,” said the study’s co-author Jeffrey Shrader  from the Center for Environmental Economics and Policy, an affiliate of Columbia University’s Climate School in New York City. “I would love to know why this is so.”

The researchers speculate that several factors may be at work. Young adults are more likely to be engaged in outdoor labour including farming and construction, and thus more exposed to dehydration and heat stroke. Young adults are also more likely to participate in strenuous outdoor sports, the researchers pointed out.

Infants and children under the age of five are also particularly vulnerable to heat as their bodies are not yet efficient in regulating temperature. Deaths of infants and young children, together with those aged 18-35, made for 75% of all heat-related deaths.

Meanwhile, people in the 50 to 70 age bracket suffered the least amount of heat-related mortality to the surprise of researchers.

Using the same daily temperature and mortality data, the researchers found that elderly people were at a higher risk of dying from modest cold, as compared to heat, at least in the Mexican context. Mexico is mainly tropical and subtropical country, but it has many climate zones including high-elevation areas that can get relatively chilly.

Younger people do most manual, outdoor labour

The new study has global implications, said the team of researchers, who along with Shrader, are mostly affiliated with Columbia, as well as Boston University, Stanford and the University of California. Many poor, hot countries, mainly in Africa and Asia, have young populations, with a large proportion working in manual and outdoor labour.

The retrospective analysis assessed heat-related deaths over a twenty-year period, from 1998 to 2019. For individuals under 35, heat causes 2.6 times more deaths than cold whereas for individuals 35 and older, cold causes 56 times more deaths than heat.

Children under five, especially infants, also had a disproportionate number of heat-related deaths, although not as large. Overall, people under 35 years accounted for 75% of historical, heat-related deaths, the researchers found.

Historical and projected annual deaths due to heat and cold exposure by age group in Mexico. Among adults, people aged 18-35 had by far the highest risk of death from heat exposure (top), with infants and children under 5 close behind.

A previous separate analysis by primarily Mexican researchers showed that death certificates of working-age men were also more likely to list extreme weather as a cause than those of other groups.

“These are the more junior people, low on the totem pole, who probably do the lion’s share of hard work, with inflexible work arrangements,” said Shrader.

The vulnerability of infants and small children came as somewhat less of a surprise. It is already known that their bodies absorb heat quickly, and their ability to sweat, and therefore cool off, is not fully developed. So exposure to temperatures that exceed their body temperature can be rapidly fatal.

Their immune systems are also still developing, which put them at higher risk of ailments that become more common with humid heat, including vector-borne and diarrhoeal diseases.

The researchers reached their conclusions by correlating excess mortality or the number of deaths above or below the average, with average temperatures in the same period, on the “wet-bulb scale” that reflects he magnified effects of heat when combined with high levels of humidity.

Despite being based mostly in the USA, the researchers y chose Mexico for the study because it collects highly granular geographical data on both mortality and daily temperatures.

Older people more likely to die of cold

Older people tend to have lower core temperatures, making them more sensitive to cold. In response, they may be prone to staying indoors, where infectious diseases spread more easily.

Despite all the attention given to the dangers of global warming, other extensive research has generally suggested that to date, excessive cold exposures, not heat, are currently the world’s number one cause of temperature-related mortality, including in Mexico. However, the proportion of heat-related deaths has been climbing since at least 2000, and this trend is expected to continue.

Around 4.1 billion people or roughly half the world’s population has experienced unusually hot temperatures between June and August this year, according to a report from US-based non-profit Climate Central.

Deaths occurred at lower-than-expected heat levels

There is a widespread recognition that temperatures alone are not a good measure of the impact of heat but “wet bulb temperatures” that also factors in humidity, are. Essentially, the same temperature level in conditions of high humidity is more dangerous than at low-humidity because humid conditions reduce the absorption of sweat, which cools off the body.

Wet bulb temperatures are often referred to as the “real-feel” heat indexes where numbers can vary depending on the exact combination of heat and humidity.

Previous research has suggested that workers begin to struggle when wet-bulb temperatures reach about 27°C, which would equate to 86 to 105°F, depending on humidity. However, the new study found that the largest number of deaths occurred at wet-bulb temperatures of just 23 or 24°C, in part because those temperatures occurred far more frequently than higher ones, and thus cumulatively exposed more people to dangerous conditions.

A study published last year showed that farm workers in many poor countries are already planting and harvesting amid increasingly oppressive heat and humidity.

Bressler, the report’s lead author, said the team is now looking to firm up its conclusions by expanding its research into other countries, including the United States and Brazil.

Image Credits: Unsplash, Study: Heat disproportionately kills young people: Evidence from wet-bulb temperature in Mexico.

The International Court of Justice in the Hague heard arguments from the WHO Director-General on Friday in a landmark case on climate justice.

Climate change poses an immediate and catastrophic threat to human health worldwide, the World Health Organization (WHO) chief warned the UN’s highest court on Friday as it considers a landmark case that could establish fresh legal obligations for nations to cut emissions and pay for climate damages.

WHO director-general Dr Tedros Adhanom Ghebreyesus testified to the International Court of Justice (ICJ) that climate change is “fundamentally a health crisis” that is already “wreaking havoc” on human health, societies, economies, and overwhelming healthcare systems worldwide.

The case, brought by the Pacific island nation of Vanuatu, represents the largest in ICJ history, with nearly 100 countries and organizations participating. While the court’s advisory opinion, expected next year, will not be binding, legal experts say the ruling could strengthen climate litigation worldwide. For small island nations, the stakes are existential – climate models predict many will disappear beneath Pacific waters without dramatic cuts to global emissions.

“The climate crisis is among the most significant health challenges facing humanity today,” Tedros told the court. “It is not a hypothetical crisis in the future. It is here and now. Without immediate action, climate-related increases in disease prevalence, destruction of health infrastructure, and growing societal burdens could overwhelm already over-burdened health systems around the world.”

The UN health chief highlighted how climate change is already altering disease transmission patterns for infections like malaria, dengue and cholera, while extreme weather events are destroying health infrastructure and claiming thousands of lives. Tedros also emphasized that noncommunicable diseases, including cancers and cardiovascular conditions, are linked to climate change and air pollution.

An estimated 920 million children currently face water scarcity, a situation he warned would worsen as climate change intensifies droughts and contaminates water supplies. Rising temperatures are also increasing heat-related deaths and illnesses. Tedros further articulated fears of massive population displacement and projected that over 130 million people could be pushed into extreme poverty by 2030, with devastating impacts on health.

“Millions are expected to be pushed into poverty. This will dramatically increase health burdens and disparities,” he said. “Not enough is being done…to avoid the most catastrophic impacts related to climate change.”

‘Health at the centre’

Iririki Island, Vanuatu.

The WHO chief criticised “massive fossil fuel subsidies,” citing International Monetary Fund projections that appropriate fossil fuel pricing that includes health and environmental costs could prevent 1.2 million air pollution deaths annually. The UN health agency estimated last month ahead of COP29 in Baku meeting climate targets could save two million lives a year.

“The value of health improvements from mitigation significantly outweighs the costs,” Tedros said. “The failure to respond to climate change is undoubtedly the most costly approach.”

WHO’s chief legal counsel Derek Walton urged the court to place health considerations at the center of its advisory opinion, emphasizing that “science and technical evidence should be at the heart of the court’s consideration.”

“WHO respectfully requests the court to place health at the center of its advisory opinion, and in this regard, to give full effect to the fundamental right of every human being to the highest attainable standard of health,” Walton said.

Walton further cited precedents in ICJ rulings that consider health as a human right, pointing to the court’s 1996 ruling on nuclear weapons.

“As the court stated nearly three decades ago in its advisory opinion on nuclear weapons, the environment is not an abstraction, but represents the living space, the quality of life and the very health of Human beings, including generations unborn,” Walton said. “We respectfully ask you to allow the science and the technical evidence to guide your analysis.”

Out of the COPs and to the courts

COP 29 in Baku, Azerbaijan

The proceedings come just weeks after December’s UN climate summit in Baku ended without meaningful commitments on emissions cuts or climate finance, even as global carbon dioxide emissions hit record highs and 2024 is confirmed as the hottest year on record.

Throughout the two-week proceedings in the Hague, which concluded on Friday, major emitters pushed back against the ICJ’s jurisdiction in the case. China urged the court to defer to existing UN climate mechanisms as “the primary channel for global climate governance,” while Saudi Arabia insisted national climate pledges represent only “an obligation of best efforts, not of results.” The United States and several EU members similarly argued existing treaties should be sufficient.

Low-lying islands, several of which called the outcome at COP29 a death sentence, argued the failure of current UN climate instruments is precisely why this case is before the court.

“We’ve heard much about the Paris Agreement as being the solution, but the reason why the climate-vulnerable states have come before the court is that the Paris Agreement has failed,” said Payam Akhavan, counsel for small island states, pointing to projections of 3.1C warming by century’s end.

Small islands represent just 1% of the global population, economy and emissions, but face existential threats from rising seas. In his remarks, Tedros recounted meeting a boy, Falou, on the island of Tuvalu five years ago who shared discussions with friends about what they would do if their island disappeared.

“They worry about the survival of their island homes due to the emissions produced by distant nations,” he said. “This reality weighs heavily on their young shoulders.”

Falou’s island home is projected to be the first nation to disappear beneath the waves. “Tuvalu will not go quietly into the rising sea,” its representative Philippa Webb told the court on Friday.

The court’s opinion, which small island states and developing countries hope to leverage in climate lawsuits worldwide, is expected in 2025. Though not legally binding, the ruling will carry significant moral and legal weight, legal experts say.

“States’ long-standing duties to prevent transboundary environmental harm and human rights violations, including from climate change, did not begin with the UNFCCC or the Paris Agreement, and they do not end with any COP deal,” said Nikki Reisch, director of the Climate and Energy Program at the Center for International Environmental Law (CIEL).

“The ICJ can and must make clear that when States breach their climate obligations, and harm ensues — as it so evidently has — they must right the wrongs,” Reisch said.

Kathmandu has introduced air sensors to monitor pollution.

More than one-third of countries worldwide lack government-level air quality monitoring, leaving nearly one billion people in the dark about one of the greatest risks to their health, a new report showed on Friday.

The assessment by non-profit OpenAQ, which maintains the largest open-source database of air quality measurements, found significant gaps in government tracking and sharing of air quality data, particularly in low and middle-income countries. The biennial report is the only global assessment of whether and how national governments are producing and sharing air quality data with the public.

Thirty-six per cent of countries provide no government monitoring of air quality, with 90% of people in nations without monitoring programs living in low and lower-middle-income countries, where the World Health Organization (WHO) says higher pollution levels and disease rates make populations especially vulnerable. A further 9% of countries do collect government air quality data but do not share it publicly, widening the gap of public access to this critical health threat even further.

Air pollution ranks as a leading cause of death and disability in all the most populated countries without monitoring, including the Democratic Republic of Congo, Tanzania, Afghanistan and Iran. Progress in expanding monitoring remains slow, with only a 3% increase in countries conducting national or subnational air quality monitoring since 2022.

“In order to deliver clean air for all, governments need to not only track air quality, but also offer an accessible, quality data set,” said Dr Colleen Rosales, OpenAQ’s Strategic Partnership Director. “Billions of people do not know what they are breathing and could benefit from greater data transparency.”

Air pollution, mainly from fossil fuel emissions, kills more than eight million people annually and costs over $8 trillion worldwide, making it the largest environmental health risk. Its impact on life expectancy matches that of smoking and exceeds that of alcohol use, transport injuries and HIV/AIDS.

Exposure to pollutants in the air affects health from birth, causing respiratory diseases, cardiovascular problems and developmental issues, with babies, young children and low-income communities facing the greatest risks. WHO data shows 99% of people worldwide breathe unhealthy air every day.

Transparent data would benefit billions 

While NGOs, academic institutions and private companies monitor air quality, government data provides unique value through continuous, comprehensive measurements. Unlike time-limited studies, government monitoring tracks a wider range of pollutants, supporting regulatory compliance, legal proceedings, health research, pollution tracking and air quality forecasting.

Only 55% of governments share their air quality data publicly, with just 27% providing it in a fully transparent and accessible format, the report found. Countries facing major air pollution crises that continue to lack transparency include China, Russia, India, Pakistan, and seven other major nations with populations of at least 70 million people.

“While many populous countries have partially shared their air quality data, an increase in transparency could benefit over 4.5 billion people,” the report said. “Barely over one-quarter of countries provide full and easy public access to data detailed enough to inform scientific inquiry and pollution reduction policies.”

Air Quality Indexes (AQI) vary widely between countries, leading to inconsistent messaging to the public about the risks of pollution levels.

Countries lacking transparent reporting frequently rely on Air Quality Index (AQI) systems that vary widely between nations, often triggering different health warnings for the same pollution levels and confusing communication with the public. While these help with daily decision-making, they lack the detailed measurements scientists and policymakers need for research and regulation.

India and Pakistan illustrate the data transparency challenges, even as their cities rank among the world’s most polluted. Both countries share air quality data only in “static, non-machine-readable formats” like PDFs and graphics rather than analysable datasets, the report said. Last month, Delhi suspended schools and construction as pollution reached twenty times WHO’s safe limit, while Lahore recorded its highest-ever levels. The severity of the crisis has forced long-time rivals toward cooperation, with Pakistan’s Punjab province seeking unprecedented talks with India.

“Although sharing data as a PDF or graphic is a good first step, when data are provided in a machine-readable, analysis-ready and standardized form, many more use cases—and ultimately, impact—can be derived from the data,” the report found. “In the quest for clean air for all, we appeal to all governments to offer data-transparent air quality monitoring versus only the 27% that do so today.”

Some nations have made progress, with 30 countries improving their monitoring or transparency since 2022. Eleven countries, including Japan, Italy and Kenya, achieved full transparency in that period.

Barriers to monitoring

Three-wheelers trapped in smog in Lahore, Pakistan in late November, 2024

Nearly one billion people live in countries without air quality monitoring, but government inaction isn’t always the cause. Many nations, particularly low- and middle-income countries, lack the financing and technical expertise to implement monitoring systems. A 2022 Clean Air Fund survey found one-third of 119 countries could not establish monitoring networks due to these constraints.

The report suggests increased investment could quickly expand monitoring, but funding remains scarce. Only 0.5% of development aid and 0.1% of philanthropic funding targets clean air initiatives. Health programs linked to climate change – a key driver of mounting air pollution deaths – receive just 2% of adaptation funds and 0.5% of multilateral climate funding.

War and civil conflict have also disrupted monitoring efforts. Air quality monitoring systems have collapsed amid wars in Ukraine and Palestine, while ongoing civil conflict in Sudan has prevented any progress on building air surveillance infrastructure.

Beyond disrupting measurement systems, warfare itself creates severe pollution. Millions of bullets, grenades, bombs and missiles detonated in Ukraine during Russia’s ongoing assault led to an abrupt spike in air pollution across Europe, with around a 10% increase in harmful pollutants such as PM2.5 and NO2 in cities near the fighting.

The health impacts of air pollution in war zones are also likely underestimated, according to research from the International Union Against Tuberculosis and Lung Disease. Even small increases in pollutants significantly raise hospitalization risks for cardiovascular and respiratory conditions, while war zones face multiple simultaneous pollution sources and populations under extreme stress, weakening their response to environmental hazards.

“In a war zone, air pollution is likely to result in more deaths than bombs,” the Union found.

Image Credits: Partnership for Health Cities.

Members of the trade union, PSLink, protesting outside the Philippines Supreme Court. The union petitoned the court to win increases for nurses.

Countries are most likely to have laws about health workers’ pay and least likely to provide them with mental health services and protection against discrimination.

There is also little correlation between a country’s wealth and the protection it offers its health workers.

These are some of the findings of a study of over 1,200 laws relating to health and care workers from 182 countries led by the O’Neill Institute for National and International Health Law and the World Health Organization (WHO).

Researchers examined the countries’ laws to see how well they aligned with the Global Health and Care Worker Compact adopted by the World Health Assembly in 2021.

The Compact was introduced to provide countries with guidelines to protect their health and care workers – a response both to the huge price health workers paid during COVID-19 and the growing shortages of health workers.

Over 115,000 health workers were estimated to have died from the virus by the time the Compact was adopted, while there is a global shortage of over 10 million health workers.

Significant gaps

The research identifies key areas where governments can use law and policy to safeguard health workers’ rights, promote and ensure decent work free from discrimination, and a safe and enabling working environment.

Around 62% of the laws were aligned with the Compact, according to Matt Kavanagh, Director of the Center for Global Health Policy and Politics at the O’Neill Institute.

“Our analysis shows significant gaps. Nearly every country has multiple areas where national laws are not yet aligned with the Care Compact, although alignment is feasible,” Kavanagh told a media briefing on Tuesday. 

The findings were published in Plos Global Health on Monday and details about the countries’ laws are available on a dedicated website that will serve as a baseline 

“While 69% of countries have some form of health services guaranteed for health workers, only 20% of those ensure that mental health and well-being are covered,” Kavanagh noted.  Twelve percent of countries had zero provision for health for healthcare workers.

“This analysis highlights the need for, and opportunity of, law reform in countries throughout the world to elevate and protect the rights and well-being of health and care workers and, in doing so, improve health systems,” noted Kavanagh.

With 105 countries aligned to half of more of the Compact’s recommendations, Kavanagh  described the report as “half-full”.

“Law reform is a key piece of what might drive us toward better retention and better effectiveness of our health and care workforces.”

One of th biggest gaps is that community health workers are usually not protected and often do not earn even the minimum wage.

Speakers at the launch of research on the protection of healthworkers (L to R): Atul Gawande, Matt Kavanagh, Catherine Kane (moderator), Laetitia Rispel, Jillian Roque and Jim Campbell

Health workers ‘are the health system’

Dr Atul Gawande, Assistant Administrator for Global Health at USAID, described the research as “transformative” as it provides both a baseline for countries to assess themselves against the Compact as well as the capacity to track progress.

“When we are talking about plans for strengthening systems, what we’re really talking about are plans for strengthening health workers. ‘Systems’ is abstract. Health workers are the system,” said Gawande. USAID assisted in funding the research.

Jim Campbell, Director of the WHO’s Health Workforce department, said the research marked a move “beyond political will into evidence-based policy”.

“Health systems are under huge challenges – population, ageing, conflict, humanitarian disasters, climate disasters. These are being transferred to the health and care workers worldwide,” he added.

With an estimated shortage of around 11 million health workers, “health systems will not have the capacity to respond to the demand, transferring a burden onto the workers that we seek to protect,” said Campbell.

“The first action has to be to invest in today’s workforce to seek those protections.”

Sub-optimal working conditions

Professor Laetitia Rispel from the School of Public Health at the University of the Witwatersrand in South Africa noted that slightly more than half of African countries had laws aligned with the Compact.

Yet Africa is going to be one of the worst affected by health worker shortages, Rispel noted.

“Sub-optimal working conditions, which are often most acute in the region, often serve as a push factor for health workers to migrate,” she warned.

Trade unionist Jillian Roque, Chief of Staff at the Public Services Labor Independent Confederation (PSLink) in the Philippines, also decried the “persistent gaps” in the protection of healthcare workers’ rights.

“In many areas, public health care workers are denied their fundamental rights to freedom of association and collective bargaining,” Roque said.

PSLink is part of the global federation of public sector workers, Public Services International (PS), which is fighting for “fair pay, decent work, equality and non-discrimination” through organising unions, said Roque. 

In the Philippines, unionists have been killed, harassed and “red-tagged” [labelled as communists], making it one of the 10 worst countries for workers in the world, she added.

Despite this, PSLink has successfully ensured the ratification of important conventions on occupational health and safety, the elimination of violence and harassment in the workplace and compelled the government to raise the salaries of nurses after filing a petition at the Supreme Court. 

Campbell noted that two-thirds of the global health workforce (67%) is women and this is often linked to the lack of protections.

Image Credits: Sophie Mautle/HeDPAC , PSLink.

A Ghanaian child receives a  malaria vaccine, which has been credited with reducing deaths in children since its introduction.

New WHO Global Malaria Report points to funding shortfalls, climate change, and antimicrobial resistance as key challenges to control.

Last year saw 263 million new malaria cases and 597,000 deaths in 83 countries worldwide, an increase of almost 11 million cases from the prior year, according to the World Health Organization’s (WHO) newly-released Global Malaria Report. The vast majority of cases occurred in the African continent, with children under five bearing the greatest burden of malaria mortality. 

Targeted interventions like insecticide-treated bed nets and integrated vector management, alongside factors such as improved nutrition, housing, and urbanization, have all reduced malaria transmission and disease in the past decades. More than 177 million cases and 1 million deaths were averted globally in 2023, and Egypt was declared malaria free, a significant milestone for Africa’s third-most populous country, according to the WHO.

Yet despite progress made in reducing the spread of the ancient disease, challenges like climate change, humanitarian crises, drug resistance, and persistent disparities all threaten global malaria progress. 

“Instead of dying, mosquitoes are dancing on the treated bed nets,” said Dr Michael Charles, CEO of RBM Partnership to End Malaria, referring to the growing number of mosquitoes resistant to commonly-used insecticides. 

Malaria burden per country in 2023

The number of new malaria cases actually increased in the past years, the report notes. Malaria case incidence – the number of new cases while accounting for population growth – grew from 58 to 60.4 cases per 1000 between 2015 and 2023. Five countries accounted for the majority of this increase in cases: Ethiopia (+4.5M), Madagascar (+2.7M), Pakistan (+1.6M), Nigeria (+1.4M) and Democratic Republic of Congo (600K). 

The WHO presented its newly-released report on the global state of malaria as a combination of both hard-fought victories, and obstinate and emerging challenges ahead of key replenishment rounds next year.

“No one should die of malaria; yet the disease continues to disproportionately harm people living in the African region, especially young children and pregnant women,” said Dr Tedros Adhanom Ghebreyesus, WHO Director-General.

“An expanded package of lifesaving tools now offers better protection against the disease, but stepped-up investments and action in high-burden African countries are needed to curb the threat.”

 

Africa ‘not on pace’ to meet WHO target

The Africa region bears the brunt of the global malaria burden – both in the number of cases and deaths – with 11 countries accounting for two-thirds of cases worldwide. Nearly half of these deaths occurred in just four countries: Nigeria (30.9%), Democratic Republic of the Congo (11.3%), Niger (5.9%), and United Republic of Tanzania (4.3%). 

Over 75% of deaths in the African region were among children under the age of five. Progress to reduce malaria mortality has barely budged in the past decade. The 2023 malaria mortality rate of 13.7 deaths per 100,000 people at risk was more than twice the WHO global strategy target of 5.5. 

While these rates remain high, many African countries have either stabilized or reduced their mortality rates. Dr Mary Hamel, WHO Team Lead for Malaria Vaccines, credits this to vaccinations for children in conjunction with bed nets and other interventions. 

“The vaccine is recommended by the WHO from five months of age, and during the pilot implementations where the governments of Ghana, Kenya, and Malawi introduced the vaccine …we saw high impact from these young age periods, with reduction in all cause mortality in these young children by 13% in all cause mortality.”

Seventeen countries have since introduced the malaria vaccine alongside childhood immunizations, with supply so far sufficient to meet demand.

WHO goals for malaria mortality rates (green) and projected rates under the status quo (blue).

Climate change, conflict, biological threats undermine progress

The many climate change-related disruptions in rising temperatures and changing weather patterns favor the quick-adapting and anthropophilic mosquito species that transmit malaria. The report warns that these changes are impacting the “health, security, and livelihoods of people around the world,” particularly in the hardest hit African region. 

But climate change is threatening malaria control in other parts of the world, like Pakistan. The devastating floods that submerged a third of the country in 2022 also left pools of standing water – “ideal breeding grounds for mosquitoes” and leading to an 8-fold increase in malaria cases between 2021 and 2023, the report notes.

Cases rose from about half a million to more than four million. The increasing frequency of extreme weather events is expected to increase the burden of malaria in the long term, especially because the mosquitoes that transmit malaria are “highly sensitive” to environmental changes, noted Dr Arnaud Le Menach, Unit Head, Strategic Information for Response, WHO Global Malaria Progamme. 

Conflict and ensuing humanitarian crises are impeding efforts to curb malaria. “In some countries, their conflict is also stopping people from getting the needed health access and the needed commodities,” said Charles. Internally displaced peoples often lack access to malaria prevention and treatment, leaving them “highly vulnerable to the disease,” said Le Menach. The report highlights these additional drivers of malaria transmission, noting that more than 80 million people in malaria-affected countries are internally displaced or refugees in 2023.

Biological threats in the form of resistant mosquitoes and antimicrobial resistance make it increasingly difficult to control vectors and treat patients. Resistance to pyrethroids, a common insecticide, was reported in nearly every country it was monitored, while resistance to artemisinin, the most effective malaria treatment, was reported in four African countries. 

Better global, regional, and country coordination is a key solution, according to Charles, to bring together stakeholders. This includes involving civil society organizations and resource optimization to overcome the above challenges. 

Reaching vulnerable populations

The global report features for the first time highlights the significant disparities in malaria burden, with a particular emphasis on gender equality.

“[W]e need to keep in mind the issue of poverty, poverty being a significant risk factor,” said Alia El-Yassir, director of the WHO Department for Gender Equality. “Malaria takes the heaviest toll on those who are poorest and are the most disenfranchised segments of a society. The data shows that children under the age of five who are living in low income households have the highest prevalence of malaria, and as their socioeconomic status improves, the risk of malaria and the prevalence will decrease.”

A host of biological, environmental, social, structural, and economic factors converge to increase a person’s vulnerability to malaria, “disproportionately” impacting those living in poverty, refugees, migrants, and indigenous peoples, notes the report.

“Poverty is very much gendered…gender norms become so deeply entrenched and institutionalized that they will place many women and girls at a disadvantage, and that affects their risk of malaria and also their access to treatment,” said El-Yassir. To address these challenges, the report urges health system strengthening to collect disaggregated data because current averages “are not giving us the true picture in terms of who is being affected.”

Calls for funding ahead of replenishment rounds

Several panelists made calls for funding at a recent WHO press conference in Geneva given the current “shortfalls” in funding. In 2023, less than half of the target $8.3 billion was invested in malaria response. This gap has widened in the past several years from $2.6 billion in 2019 to $4.3 billion in 2023. The vast majority of these funds come from international sources, with endemic countries contributing 33% in the past decade.

“Next year is a very, very big year for all of us in the malaria world,” noted Dr Charles. “We have two replenishments. We have the GAVI replenishment, and we also have the Global Fund replenishment…The mosquito is so unrelentless and so smart that the longer we wait, the harder it is.”

Even with malaria vaccines available, GAVI, the Global Fund, and the President’s Malaria Initiative all need replenishment “to realize the promise of the vaccine and other interventions,” argued Dr Hamel.

The Global Fund also released a statement urging funding to meet targets, making the argument that “investing more in the fight to end malaria not only has the potential to save millions of lives, but it can also help rebalance global economic power and stimulate trade.

“This, in turn, can unlock additional funding to strengthen health systems and enhance health security both in Africa and around the world. Malaria investment is not just a health imperative—it is a strategic driver of broader, far-reaching economic and social benefits,” said Peter Sands, Global Fund executive director, in a press release.

Image Credits: Fanjan Combrink / WHO.

Africa CDC Director-General Dr Jean Kaseya (centre) during a visit to the DRC last week.

There is still no clarity about the cause of the mystery disease affecting people in the Panzi district of Kwango province in south-west Democratic Republic of Congo (DRC), despite hopes that it would be diagnosed by the past weekend.

Getting laboratory test results is proving more challenging than previously hoped as the district’s “limited laboratory capacity means that samples have to be transported to the national reference laboratory in [the capital of] Kinshasa”, according to the Africa Centres for Disease Control and Prevention (Africa CDC).

But the 700 km journey to Kinshasa currently takes about 48 hours due to poor roads and the rainy season, according to the World Health Organization (WHO).

The communication network is also limited in Panzi, a rural community of around 200,000 people spread over more than 7,000 square kilometres.

Suspected diseases

By last Thursday, 406 cases and 31 deaths of the undiagnosed disease had been recorded (case fatality ratio of 7.6%). However, the reported cases peaked in epidemiological week 45 (week ending 9 November 2024), according to the WHO. It took almost six weeks for Panzi health officials to notify national health officials about the unusual rise in cases.

All severe cases were malnourished, according to the WHO’s Disease Outbreak News (DON) from Sunday.

“The clinical presentation of patients includes symptoms such as fever (96.5%), cough (87.9%), fatigue (60.9%) and a running nose (57.8%),” according to the WHO.

Almost two-thirds of cases (64.3%) are children under the age of 15 , and over half of the children’s cases involve kids under the age of five. Some 71% of deaths occurred in children under 15.

“The area experienced deterioration in food insecurity in recent months, has low vaccination coverage and very limited access to diagnostics and quality case management,” according to the WHO.

In addition, the area is experiencing a shortage of supplies and health workers, with limited malaria control measures and access to transport.

Given the context of Panzi and patients’ symptoms, the WHO has listed the main diseases that are suspected. These include measles, influenza, acute pneumonia (respiratory tract infection), hemolytic uremic syndrome from E. coli, COVID-19 and malaria. 

Both the WHO and Africa CDC have sent health experts to assist the DRC’s team to assess the situation, accelerate diagnostic testing, and implement control measures.

The multidisciplinary team includes epidemiologists, laboratory scientists, infection prevention and control experts.

Since the mpox outbreak, the Africa CDC has been working closely with the DRC’s Ministry of Health (MoH), the National Institute of Biomedical Research (INRB), the National Public Health Institute (NPHI) to strengthen disease monitoring through genomic surveillance. 

“This collaboration focusses on creating a sustainable national pathogen genomics strategy and decentralising laboratory capacity to improve outbreak response and preparedness,” according to Africa CDC.

INB co-chair Precious Matsoso (centre) ends the 12th meeting, flanked by co-chair Anne-Claire Amprou and Dr Tedros.

There will be no pandemic agreement by year-end and, with only 10 days of formal talks set aside in 2025, some parties doubt whether an agreement can be reached by the May 2025 deadline.

The week-long extended 12th meeting of the Intergovernmental Negotiating Body (INB) made progress, particularly on research and development (Article 9) and financing (Article 20). 

While disagreement remains on a couple of key obstacles, informal talks will continue alongside the formal talks.

Dr Tedros Adhanom Ghebreyesus, the World Health Organization’s (WHO) Director General, suggested at the close of the meeting on Friday evening that delegates consider negotiating on “packages” rather than clause by clause to “break the stalemate”.

“When I see what’s left, I believe – and this is honest from my heart – it is not really difficult to conclude in a few days of negotiation, but between now and the next meeting it would be good to think about the issues left and find a middle ground,” said Tedros.

Earlier in the day, INB co-chair Anne-Claire Amprou took exception to criticism of the process and lack of progress from some NGO observers.

Noting that the nature of multilateral negotiations means finding a “landing zone” that is acceptable to everyone, France’s Amprou said sharply: “I don’t agree when you say that nobody gains anything. I invite everyone – delegations, stakeholders – to look at what we have already achieved. We have achieved a lot.”

She stressed that the INB would deliver on its mandate: “We need a pandemic agreement which is meaningful, and it will be.”

‘Not a colouring book’

Amprou’s response came after Medicines Law and Policy commented that while there is some new “green text”, indicating agreement on the draft agreement, “it’s important to remember that the pandemic agreement is not a colouring book”. 

The European think-tank continued: “Substantive provisions on very difficult issues such as equity and access, transfer of technology, intellectual property and [pathogen] access and benefit-sharing remain largely absent, or are, at best, weak.”

Third World Network (TWN) followed, saying: “Every time we hear a new text is green, we are looking to figure out what has been compromised, especially in terms of equity.

TWN added that the agreement lacks “a baseline of legal rights and obligations”, and  “protects the interest of business, not people’s rights”.

Oxfam presented a list of questions and objections on behalf of 26 stakeholders including that member states appeared to be under “extreme pressure” to defer agreement on a pathogen access and benefit-sharing (PABS) scheme to an annex, the contents of which would be decided on after the pandemic agreement had been signed.

The Pandemic Action Network (PAN) and the Panel for Global Health Convention both urged negotiators to keep the momentum going and asked for clarity on the way forward.

Rafael Gracia of Pandemic Action Network and Dame Barbara Stocking representing he Panel for Global Health Convention

Eloise Todd, PAN’s executive director, told Health Policy Watch after the meeting that while the INB has not reached a conclusion, “there is a more urgent sense of progress around the negotiations which we need to encourage”.

Todd called on “high-income countries in particular to dig deep and remember the reason why we need this agreement is because of the deep-seated inequality in the COVID response”. 

“⁠⁠It is crucial for negotiators to see the bigger picture with these negotiations. The pandemic agreement will serves as an important marker the world’s coordination and cooperation in times of pandemic threats – which we know will become more and more frequent. It’s time to deliver on this vital step forward that will benefit people in every country,” said Todd.

However, Spark Street Advisors’  CEO and long-time talks observer Nina Schwalbe was less positive: “They have missed a once-in-a-generation opportunity to make a difference because national interests prevailed over global solidarity.”

Crux of the stalement

The stalemate centres on differences between the European Union (EU) and the Africa Group. The EU wants an annex linked to Article 4 (pandemic prevention) that outlines countries’ responsibilities to prevent pandemics. The Africa Group is reluctant to agree to costly responsibilities and it wants an annex related to the operationalising of a system for pathogen access and benefit-sharing (PABS) in exchange.

What the Africa Group wants from PABS is preferential access to any pandemic-related products that are developed from them sharing information about pathogens that could cause pandemics. This is anathema to the pharmaceutical industry, largely represented by the EU and the US.

The Africa group is also concerned that a prevention annex could impose costly requirements that they are unable to finance. However, the first beneficiaries of prevention measures are individual countries’ citizens who would be protected by, for example, heightened surveillance of bats that harbour Ebola and Marburg.

“These two areas are the make-or-break articles of the negotiations. If we can reach agreement on these, we will make the deal,” co-chair Precious Matsoso noted in an address to scientists recently.

Health leaders wanted an early agreement

Tedros has long urged delegates to reach agreement sooner rather than later and Dr Jean Kaseya, head of Africa CDC, has also expressed hope for an early agreement.

On a recent visit to South Africa, Matsoso noted: “We don’t have six months left to finish negotiations. We only have a couple of days left, precisely because the geopolitical environment is so challenging. There is huge, huge pressure on the talks and we don’t know what the outcome will be.”

The elephant in the room is the Donald Trump presidency, largely expected to take an axe to what Team Trump terms “globalism” – virtually anything that puts global good before national interest.

Delegates paid tribute to US Ambassador Pamela Hamamoto for her positive contribution to the pandemic agreement, as that was her last INB meeting.

Further INB meetings are scheduled for February and April, with a completed agreement supposed to be ready to be voted on at the World Health Assembly in May.

Mosquito and dengue
Mosquitoes, which can carry dengue virus, thrive at warmer temperatures. Climate change is already fueling increases in dengue cases globally.

Nearly one fifth of dengue cases in Latin America and the Caribbean, or about 45 million infections a year, are attributable to climate change, in the past decade, according to a new study by researchers at Harvard and Stanford Universities. 

Rising temperatures combined with mosquito species uniquely suited to sprawling urbanization and deforestation are fueling the staggering increase in dengue cases, with a proportion of cases measurably attributable to climate change, according to the first ever study to “meaningfully” quantify that number. 

Over the past year, both Latin America and the Caribbean saw a record-breaking number of cases – and fatalities – of the so-called “break-bone” fever. Even with the recent regulatory approval of two new vaccines, Takeda Pharma’s Qdenga® and Sanofi’s Dengvaxia, slow rollout and continued challenges in production scale-up have meant the jabs made little impact so far. 

The researchers compiled data from 21 countries in the Americas and in Asia to identify the causal effect of climate change-related temperature increases and dengue cases. The study was presented at the Annual Meeting of the American Society of Tropical Medicine and Hygiene (ASTMH) 13-17 November, and is available in pre-print form.

The researchers also estimated how different climate change scenarios will impact dengue burden. By 2050 under a high CO2 emissions scenario, the authors predicted  a 61% increase in dengue incidence. Active climate mitigation would cut that figure to roughly 40%. 

At least 257 million people now live in countries where warming temperatures could cause dengue to double by mid-century in either scenario. 

“We can see the direct policy implications of reducing emissions at the global scale,” Dr Kelsey Lyberger, an ecologist at Arizona State University and one of the study authors, told Health Policy Watch. The magnitude of dengue cases will not increase equally, either, Lyberger noted. “Some of the highest relative increases are in places where they don’t necessarily have a high burden currently.”

Dengue and climate change projections
Countries in cooler climates are projected to have the largest increase in climate change-related dengue cases.

But already now, increasing temperatures and extreme weather events are already changing the burden of infectious diseases – particularly vector-borne diseases. These temperature increases are already responsible for 45 million excess dengue cases, which the studied identified.  

The study, whose release coincided with the UN Climate Conference (COP29) in Baku, provides further evidence that climate action is “health action,” as termed in a recent WHO COP29 special report.

Cooler regions will see largest change

Dengue responds non-linearly to average daily temperature, with cases peaking at average temperatures of 28℃, and then decreasing. This creates “optimal” conditions for the two primary dengue mosquito vectors, Aedes aegypti and Aedes albopictus, where both species breed and feed faster. But in places where average temperatures are cooler – 15-20℃ on average – climate-change related warming has the largest effect on dengue caseload. 

As a result, projected warming will fuel dengue cases unequally across the globe. “It’s not across the board that we see this increase,” said Lyberger.  

Some cooler regions of Mexico, Peru, Bolivia, and Brazil, for instance, are predicted to see over 150% increases in dengue incidence due to climate change under any emission scenario, the study notes. 

Lack of surveillance data excludes Africa, India, Western Pacific from analysis

Dengue infographic
WHO’s Western Pacific region was among those excluded from the study due to a lack of reliable surveillance data.

While dengue cases continue to rise globally, including in much of the African continent, the lack of high quality surveillance systems means experts are left to guess the impact of climate change on dengue in these regions. 

Countries in the America, Brazil in particular, have felt the burden of dengue cases most acutely, but they often have surveillance methods in place to track infection rate fluctuations.

“We needed a long enough time series of cases to estimate a baseline level of dengue,” said Lyberger. Many African countries face surveillance hurdles in detection, reporting and management, the lack of local laboratory capacity, and the misclassification of cases, noted researchers at Africa CDC. Without a solid surveillance system, countries are at a critical disadvantage–including little early warning systems for dengue surges.

In India, the country’s “poor” surveillance network leads to “huge” under-reporting and a lack of public health response to outbreaks, as a Lancet editorial comments in India’s 2015 dengue season. A 2020 assessment of the country’s surveillance efforts found that dengue surveillance needs to be strengthened, and integrated into existing government initiatives. In that time frame alone, from 2015-2019, cases in the South Asian region increased by 46% according to WHO estimates. The organization attributes climate change, in addition to “high rates of population growth, inadequate water supply and poor waste management systems” coupled with the absence of effective treatment and suitable vector control to the high burden of dengue in the region. 

Preparing for the future

With these new estimates of how climate change will increase dengue cases, researchers hope that such high-burden countries will be motivated to do more tracking and reporting, while those that historically have had few cases can prepare with funding for surveillance and integrated vector management. 

“Since we’ve established this relationship between temperature and cases, the next step is to see how warming, both in the past and in the future, is going to affect the number of cases that we have or will see,” explained Lyberger.

This led researchers to compile data from 21 countries where dengue is endemic – including Brazil, Cambodia, Colombia, and Vietnam – and to examine other factors that could affect dengue infection rates like rainfall, seasonal changes, viral strains, economic shocks, and population density, to isolate the distinct effect of temperature. 

“We were able to pin down that historical warming has already increased dengue cases by about 20%,” said Lyberger. 

“It’s evidence that climate change already has become a significant threat to human health and, for dengue in particular, our data suggests the impact could get much worse,” said Erin Mordecai, PhD, an infectious disease ecologist at Stanford’s Woods Institute for the Environment and the study’s senior author in a press release. 

See Health Policy Watch’s ongoing coverage of dengue here.

Image Credits: Marissa L. Childs, Kelsey Lyberger, Mallory Harris, Marshall Burke, Erin A. Mordecai, WHO.

DRC Director-General of Health, Dr Dieudonné Mwamba.

The Democratic Republic of Congo (DRC) expects to diagnose ‘Disease X’, which has killed at least 79 people in the Panzi district of Kwango Province by the weekend, according to the country’s Director-General of Health, Dr Dieudonné Mwamba.

“The disease is characterised by fever, headaches, cough and sometimes difficulty breathing,” Mwamba told a media briefing hosted by Africa’s Centre for Disease Control and Prevention on Thursday. 

So far, around 376 people have been infected and the disease appears to be airborne, he added. Females are slightly more affected than males, and the majority of cases (52%) are under the age of 5. The second biggest group of patients is people aged over 25 (almost 30%).

“Given that we do not have a specific diagnosis, we don’t know whether we are faced with a viral or bacterial disease, but we believe that, in under 48 hours, the results of the laboratories will help us,” he said.

However, he noted that people in the impoverished rural Panzi district were “vulnerable” as there is a malnutrition rate of almost 40%, it recently experienced a serious typhoid outbreak. The DRC is also experiencing a seasonal influenza outbreak.

Panzi does not have the capacity to test the specimens taken from patients with the unknown disease, so they have been sent to a laboratory in Kikwit some 500km away.

The first case of the unknown illness was identified on 24 October in the largely rural south-eastern province bordering Angola. However, central authorities were only notified of a possible outbreak on 1 December, according to Dr Jean Kaseya, Africa CDC Director-General, who addressed the briefing from the DRC.

“We want to reinforce the surveillance. We have a delay of almost five to six weeks, and in [that time], so many things can happen. This is why we are supporting the country to build strong capacity for surveillance,” said Kaseya.

A team from Africa CDC, including an epidemiologist and laboratory and infection prevention control (IPC) experts, is being sent to Panzi on Friday to assist officials, he added.

Mpox continues to spread

Meanwhile, Mpox continues to spread, particularly in Central Africa, with 2,700 new cases in the past week, up from 2,618 new cases the previous week,  said Kaseya.

The outbreak has affected 20 African countries. After laboratory testing, Zambia and Zimbabwe have confirmed that their outbreaks are Clade 1b.

“In total, we have 62,171 cases. Last week, we lost 36 people, and that brings a total of 1200 deaths since January 2024,” said Kaseya.

However, only 13, 579 of the cases have been clinically confirmed as laboratory testing remains a challenge in many areas.

The DRC remains the worst affected by mpox, with both clade 1a and 1b circulating. The lion’s share of the week’s new cases – 2,115 – were identified in the DRC and all 36 of the week’s deaths were in the DRC.

However, testing remains a challenge in the country, with only 20% of cases confirmed by laboratories.

Africa CDC also flagged the links between high burdens of mpox cases and measles cases in DRC, but has not yet established a causal link between the two diseases.