Cuts to global immunisation budgets are hitting measles vaccine coverage, disease surveillance, laboratory networks and outbreak response the hardest, according to the Strategic Advisory Group of Experts on Immunization (SAGE).

SAGE, which advises the World Health Organization (WHO) on immunisation, issued the warning at a media briefing on Tuesday after its four-day biannual meeting.

It warned that the recent cuts by the Trump administration in the United States create a risk of further backsliding in immunisations “just when countries are recovering from the impact of the COVID-19 pandemic”. 

“The number of zero dose children, meaning those children that have not received any vaccines, have increased, even though the big [post-COVID] catch-up has helped,” SAGE chair Dr Hanna Nohynek told the media briefing.

Dr Kate O’Brien, WHO’s head of immunisation, said that vaccines have saved at least 154 million lives over the past 50 years, “and 60% of those lives saved were attributable to the measles vaccine”. 

Measles labs shutdown

However, WHO’s global measles and rubella network of more than 700 laboratories, funded solely by the US, faces “imminent shutdown”, WHO Director-General Dr Tedros Ahhanom Ghebreyesus told a media briefing on Monday. 

The collapse of the network, called Gremlin, would mean that outbreaks would not be detected – either at all or not rapidly, said O’Brien.

“Measles is one of the most infectious viruses, and it can have serious consequences, including infections of the brain, of the lung, pneumonia and  encephalitis,” she noted.

“The purpose of detecting [measles outbreaks] rapidly is to stamp them out at source as quickly as possible and to respond,” said O’Brien. 

She warned that measles was already surging, with 57 countries having outbreaks last year, in comparison to 35 countries in the two prior years. 

“Without that lab network and the epidemiologists, scientists and public health workers that are part of that response, we will certainly see many, many more outbreaks, many, many more deaths and many, many more cases,” said O’Brien.

Gremlin costs $8million a year, which O’Brien described as a “best buy” investment to save lives. It had been funded by the US Centers for Disease Prevention (CDC) not the US Agency for International Development (USAID).

The major theme of the four-day meeting was the “very high concern” of SAGE members of the impact of the funds cut on the “eradication, elimination and control of diseases”, added O’Brien.

Polio transmission

SAGE is “highly concerned” about the continued transmission of wild poliovirus in Pakistan and Afghanistan and the circulation of vaccine-derived poliovirus type 2 and its expansion into new areas, including European countries.

SAGE also reviewed updated evidence and concluded that a polio vaccination schedule with a minimum of three vaccine doses of the inactivated poliovirus (IPV), starting at six weeks of age or later is adequate, without the need for a scheduled IPV booster dose (4th dose). 

SAGE reaffirmed that three doses of pneumococcal conjugate vaccines (PCVs) is the most effective way to prevent childhood pneumococcal disease. 

SAGE noted that PCV10 by the Serum Institute of India had recently received WHO-prequalified for the immunization of infants, joining PCV10 (GlaxoSmithKline) and PCV13 (Pfizer).

It also recommended varicella vaccines, using a two-dose schedule with a minimum four-week interval between doses, for children in populations where varicella is an important public health problem. 

Varicella vaccination could also be introduced for special populations, such as immunocompromised people, those living with well-controlled HIV infection and health workers in areas where they 

SAGE also received a report from the global vaccine platform, Gavi. Highlights include that Gavi’s HPV vaccine initiative is on track to immunise 86 million girls by the end of the year,  while significant progress has been made in rolling out malaria vaccines.

Gavi will invest $800 million in polio vaccines this year and $5.6 million to address mpox.

Gavi aims to launch a new strategy in 2026 that will focus on introducing new vaccines, strengthening country programmes, and reducing zero-dose children.