Recent research highlights that the JN.1 variant of Covid-19 has the capability to infect cells in the lower lung region, leading to more severe symptoms. Published in the journal Cell in early January, the study reveals that JN.1 exhibits enhanced adherence to cells, participating in host cell membrane fusion.

JN.1 is considered the next generation of BA.2.86, featuring approximately 60 more mutations in the spike protein compared to the original nCoV version and 30 more mutations than the nearest major strain, Omicron (including BA.2 and XBB.1.5). Scientists express concerns that the multitude of changes and mutations may result in challenging outbreaks similar to Omicron in 2021 and 2022.

According to Shan-Lu Liu, the lead author of the study and a virology professor at the Ohio State University, BA.2.86 and its descendants exhibit a significantly better ability to infect lung epithelial cells compared to earlier Omicron strains. This raises potential concerns about the virulence of the virus, especially at a time when vaccines are less effective and public vigilance may be diminishing.

Professor Liu emphasizes that individuals who have had previous Covid-19 infections should be aware that Omicron is less virulent than earlier strains, such as Delta, resulting in milder symptoms. Consequently, the antibodies produced in response to natural infection are approximately 10 times lower than those generated by vaccines. This underscores the importance of not relying solely on natural infection to boost immunity, with vulnerable individuals, including those with underlying medical conditions, being recommended to receive annual vaccinations.

BA.2.86 and its descendants, particularly JN.1, are spreading across various countries, and the World Health Organization (WHO) has classified them as “variants of concern” (VOI) since December. JN.1 is associated with symptoms such as cough, muscle pain, sore throat, headache, and a runny nose. In the United States, JN.1 is most prevalent in the Northeast regions, including New Jersey and New York. It is recognized as the fastest-growing mutation and is under close monitoring. Thailand has also reported cases of severe illness and deaths from JN.1 infection, primarily affecting individuals who were not vaccinated or were not fully vaccinated.