The JN.1 COVID-19 variant is completing its global takeover, with the number of new cases having increased by 52% during the 28 days leading up to the end of the year, according to the World Health Organization (WHO). 

In the United States, JN.1 accounts for more than 60% of COVID-19 cases, according to the Centers for Disease Control and Prevention – and all of this on top of rising influenza and Respiratory Syncytial Virus (RSV) waves. 

“The pandemic is far from over,” stressed American scientist Eric Topol in an opinion piece in the Los Angeles Times. 

What is JN.1?

JN.1 is a derivative of the BA.2.86 Omicron subvariant of SARS-Cov-2 but with more than 30 mutations. Israeli variant trackers first discovered it in August. WHO first spoke about JN.1 at a press conference on 19 October press as a variant “to keep a close eye on.” Last month, it named JN.1 a “variant of interest” (VOI) but nit the more serious “variant of concern” (VOC). 

According to Topol, “by wastewater levels, JN.1 is now associated with the second-biggest wave of infections in the United States in the pandemic, after Omicron.” He said the level indicates that around two million Americans are infected with JN.1 daily.

Although many people are carrying the virus and CDC data shows that US COVID-19 hospitalizations have continued to increase in the last two months, JN.1 has not caused the surge of hospitalizations seen in Omicron. 

This is also the case in other countries, including Israel, where it was first discovered, according to Cyrille Cohen, the head of the field of life sciences and medicine for the Israel Science Foundation and a professor at Bar-Ilan University. He said the country is seeing 10 to 20 cases of severe COVID-19 disease in hospitals on any given day, compared to as many as 1,400 two years ago. 

At the same time, studies are starting to show that the updated COVID-19 vaccines developed by Pfizer, Moderna and others are eliciting antibodies against JN.1 – at least in vitro, according to Cohen. 

For example, Kaiser Permanente recently released a report that showed a vaccine booster conferred approximately 60% protection against hospitalization for JN.1 and other recently identified variants. 

However, Cohen cautioned that it can be challenging to determine the impact of COVID-19 vaccines today as people have had so many shots at different intervals and of different versions. Moreover, most people have either been exposed to or are sick with COVID-19. 

The other issue is that vaccine uptake is deficient. CDC data as of 5 January showed that only 8% of eligible children and 19.4% of eligible adults had received the updated 2023-24 COVID-19 vaccine. The percentage jumped to around a third (38%) among adults over 65. 

Many more people are opting to take the influenza vaccine: 44% of children and 45% of adults, including 70% of adults over 65. 

Evaluating JN.1: What to ask

Whenever there is a new variant, you need to ask three questions, explained Peter Chin-Hong, a professor of medicine and infectious disease at the University of California, San Francisco: Is it more transmissible? Do the vaccines work? Does it cause more severe disease?

Is it more transmissible?

Chin-Hong told Health Policy Watch that the data indicates JN.1 is more transmissible “because it is rising to the top of the charts very quickly.” He said that at the beginning of November 2023, JN.1 accounted for between 5% and 8% of all US cases, and today it is the most common variant. 

Can it evade vaccines?

The answer here, Chin-Hong said, is generally no. He said the studies show that the vaccine works as long as people are newly inoculated. He recommended the vaccine for immuno-compromised people with pre-existing medical conditions and those over the age of 75. For these people, he said, “just being infected a year ago and getting the first two shots will not be enough.”

Does it cause more severe disease?

According to Chin-Hong, there is no evidence that JN.1 has caused more severe diseases so far and no evidence that it will. This is true in the countries currently experiencing a rise in the variant, and also from data in Singapore and other countries where JN.1 has been the predominant variant for longer, he said. 

In those countries, the variant did not seem to cause more people to be hospitalized. 

Moreover, he added that antiviral drugs such as Paxlovid and Remdesivir continue to work to curtail the severity of the virus. 

Instead, he said his concern is that JN.1 will exploit the world’s COVID-19 complacency. The majority of countries have not kept up testing or vaccination, and given its high price tag, many low- and middle-income countries do not have access to drugs like Paxlovid. 

“Those are the vulnerabilities that JN.1 will exploit,” Chin-Hong said. 

COVID-19: ‘a new era’

But Cohen said he believes the world and COVID-19 are “in another era” since WHO ended the virus’s official pandemic status in May 2023. He noted that COVID-19 is not the same threat as at the pandemic’s beginning or even during Delta. 

“With the Omicron era that started exactly two years ago, the infection decreased in intensity,” Cohen said. Moreover, “since most of us were exposed to COVID at least once in our lifetime, there is also some kind of protective [herd] immunity.”

That does not mean, however, that the medical and scientific community should not be taking JN.1 or COVID seriously, Chin-Hong stressed. He said WHO should hurry to give the variant a Greek letter name, such as Pi, to “allow governments and people to mobilize” and fight the virus. 

“Right now, people are fed up with COVID,” Chin-Hong told Health Policy Watch. “Giving it a letter will give something to people to latch onto: let’s vaccinate against Pi, get medicines, and have a global talk about sequencing.

“These things have trickle-down effects,” he continued. “Giving it a name would also help the everyday person believe he still has something to pay attention to.”

Chin-Hong and Cohen said that information remains crucial and that countries should continue to sequence to identify variants of concern. 

“We need to monitor those variants because it is not the end of COVID,” Cohen said. Just like with flu, which has an intense strain every 10-20 years, he said that COVID-19 could also once again have a more dangerous strain.”

As Topol wrote in the LA Times: “Inevitably, there will be another strain in the future that we are not at all prepared for and will lead to yet another very big wave across the planet.”

Image Credits: Photo by Mufid Majnun on Unsplash.