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New COVID variant causing rise in infections during busy holiday travel season

December 20, 2023
by Colin Poitras

A new COVID-19 variant known as JN.1 is rapidly spreading across the United States and Europe as we head into peak holiday season travel time. The CDC reports that cases of JN.1 infections more than doubled in the U.S. between late November and mid-December and JN.1 is now considered the fastest-growing variant of the virus. JN.1 is an Omicron subvariant with mutations to its spike protein that allow it to bind tightly to cells in the respiratory tract and cause infection. The variant is currently dominant in the Northeastern U.S. Dr. Michael Cappello, MD, chair of the Yale School of Public Health’s Department of Epidemiology (Microbial Diseases), recently took a moment to discuss the new variant, its threat potential, and what people can do to protect themselves from infection.

What is the JN.1 variant and how is it different from the other COVID-19 variants we’ve experienced?

MC: The JN.1 variant is closely related to the other circulating variants, including the BA.2.86 variant that you may have heard of. It’s not completely clear why this variant has become more common over the past few months, but according to the U.S. CDC, JN.1 may represent up to 30% of the SARS-CoV-2 strains currently circulating in the United States.

Will the latest COVID-19 vaccine protect me from JN.1 infection?

MC: Yes, the most recently updated vaccines should protect equally well against JN.1, which although it may be more transmissible than other variants, doesn’t yet appear to cause more severe symptoms or illness in those who get infected.

Should I start wearing a mask again to protect myself and others from JN.1 infection?

MC: As we enter the holiday season, the number of cases of COVID-19 is increasing across the country, so doing everything you can to protect yourself and those with underlying medical conditions is one way of showing that you care. Indoor settings with limited ventilation, including airplanes, are often associated with increased transmission of respiratory viruses, including RSV, influenza, and SARS-CoV-2. It’s difficult to assess the risk in every situation, but wearing a high-quality mask provides protection to you and those around you by reducing the risk of spread of respiratory illnesses.

Submitted by Colin Poitras on December 20, 2023