Rapid Spread of Coronavirus Subvariant JN1 in US, Gaining Dominance in the Northeast
The CDC estimates that Covid-19 subvariant JN1 is rapidly spreading in the US, causing 20% of new infections Dominating the Northeast, it accounts for about a third of new cases Stay updated with CNN Health's weekly newsletter
The US Centers for Disease Control and Prevention has stated that the JN.1 subvariant of the coronavirus is now responsible for approximately 20% of new Covid-19 infections in the country, making it the fastest-growing strain. This subvariant is currently predominant in the Northeast, where it is believed to be the cause of about a third of new infections.
JN.1 is a descendant of BA.2.86, or Pirola - a subvariant that gained worldwide attention over the summer due to its spike protein mutations, exceeding 30 in number. There were concerns among scientists that these mutations could render it capable of eluding the protection offered by vaccines and antibodies against Covid-19, potentially triggering a new wave of illness, akin to the one caused by the original Omicron variant in 2021.
A pharmacy in New York City offers vaccines for COVID-19, flu, shingles and pneumonia on December 6, 2021.
Ted Shaffrey/AP
You can get Covid-19 and flu vaccines at the same time, but should you? What the science says
The event never occurred, however BA.2.86 lingered, exhibiting slow growth in certain countries such as the US. Studies hinted that its inability to gain momentum could be attributed to a potential decrease in its capacity to infiltrate our cells.
In comes JN.1, which is two iterations later - essentially a grandchild - of BA.2.86. JN.1 has only one alteration in its spike protein compared to its predecessor, yet this seemingly minor change has rendered it a more adept and rapid virus.
According to the CDC, the prevalence of JN.1 has more than doubled in the US from late November to mid-December, possibly fueled by holiday travel and decreasing immunity.
Dr. Shishi Luo, who leads infectious diseases at the genomic sequencing company Helix, observed, "When I just look at the growth curve, it is rising quite sharply, and it seems to coincide with the Thanksgiving break in terms of timing."
Experts anticipate that it will soon emerge as the dominant coronavirus variant worldwide, outpacing existing XBB variants. Dr. T. Ryan Gregory, an evolutionary biologist at the University of Guelph, has been monitoring the virus's evolution and commented, "It's evident that this variant is highly competitive and appears poised to become the next globally dominant group of variants."
The mutation in the spike protein of the JN.1 variant appears to aid the virus in evading our immune response, as noted by Gregory. Research conducted at Columbia University and in China indicates that there is roughly a 50% decrease in our antibodies' ability to effectively neutralize this subvariant. While this decrease may not be significant, it could be an indicator of a potential upcoming increase in infections.
Several European countries - such as Denmark, Spain, Belgium, France, and the Netherlands - have experienced a dramatic increase in JN.1, leading to a surge in hospital admissions. Additionally, JN.1 is spreading rapidly in Australia, Asia, and Canada.
On Thursday, October 12, 2023, in Pasadena, CA, Allissa Sanchez, LVN, administered a vaccine to a patient during a flu and COVID-19 vaccination clinic at Kaiser Permanente Pasadena. The event was captured by Francine Orr of Los Angeles Times/Getty Images.
The CDC is raising concerns about low vaccination rates as respiratory virus activity increases. This is occurring in the United States as well due to decreasing immunity. Many Americans have opted out of getting the latest Covid-19 vaccination, potentially skipping it last year as well. As a result, their immunity has not been strengthened to protect against severe consequences of Covid-19 infections.
As of December 9, only approximately 18% of adults have received the latest Covid-19 vaccine, a similar low percentage to last year, as reported by the CDC.
The CDC is urging doctors to exert more effort in getting their patients vaccinated, stressing that it is not too late in the season to reap the benefits of the vaccine.
In the past four weeks, Covid-19 hospitalizations have increased by 51%, prompting a warning from the CDC. Alongside rising hospitalization rates for flu and RSV, the agency cautioned that continued increases could strain hospital capacity. However, a recent study from Dr. David Ho's lab at Columbia University revealed that the current Covid-19 vaccine, originally intended to enhance the immune system's response to the XBB variant, also provides effective protection against BA.2.86 and its related strains, including JN.1.
Sign up for CNN Health's weekly newsletter to stay informed about the latest findings on Covid-19 vaccines and other health updates.
Register here to receive The Results Are In with Dr. Sanjay Gupta every Tuesday from the CNN Health team.
The World Health Organization recently endorsed the enhanced Covid-19 vaccines for XBB.1.5, citing their wide-ranging protection against numerous variants.
Dr. Alex Greninger, assistant director of the Clinical Virology Laboratory at the University of Washington, expressed concern over the declining rates of booster vaccinations and Paxlovid usage. He emphasized the importance of utilizing these tools that can effectively reduce the risk of severe illness and death from Covid-19.
