For a third season, COVID-19 cases are rising ahead of the holidays, this time with a more recent Covid variant JN1 driving infections.
The Centers for Disease Control and Prevention has estimated that the Covid Variant JN1 now makes up approximately 44.1% of cases across the United States, marking another week of the fast-spreading variant’s steep rise.
The CDC believes that JN.1’s prevalence is largest in the Northeast region, spanning New Jersey and New York, where it accounts for 56.9% of cases in those states. The emergence of the new variant has caused concern among health officials, who believe that it may be more transmissible or better at evading our immune systems than other circulating variants. However, officials believe that the public health risk from JN.1 is no greater than that of other recent strains. Although the new variant has not reported different or more severe symptoms compared to previous strains, its unprecedented accumulation of mutations, most inherited from JN.1’s highly mutated parent BA.2.86, has kept health authorities on guard.
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Effectiveness of Vaccine against Covid Variant JN1
The effectiveness of COVID-19 vaccines against JN.1 is still being studied, but early data suggests that this season’s COVID-19 vaccines may still be effective against the variant. Health authorities are closely monitoring the situation and ramping up scrutiny of the new strain to ensure public safety.
The vaccine has been a significant topic of discussion globally, with extensive research and development underway to ensure its effectiveness and safety. Various COVID-19 vaccines have been authorized for emergency use, and their distribution and administration have become a major priority for many countries.
CDC’s Update on Covid Variant JN1
What CDC knows
The CDC is tracking the JN.1 variant of SARS-CoV-2, projected to account for 39-50% of circulating variants in the United States as of December 23, 2023. This variant is increasing more rapidly than others, but existing vaccines, tests, and treatments are effective against it. The spread of JN.1 does not appear to pose additional risks to public health at this time, and the CDC is closely monitoring the situation.
What to Do If You Were Exposed to Covid Variant JN1?
If you were exposed to the virus that causes COVID-19 or have been told by a healthcare provider or public health authority that you were exposed, here are the steps that you should take, regardless of your vaccination status or if you have had a previous infection.
Use this tool to help you determine if you need to isolate or take other steps to prevent the spreading of COVID-19.
Wear a mask as soon as you find out you were exposed
Start counting from Day 1
- Day 0 is the day of your last exposure to someone with COVID-19
- Day 1 is the first full day after your last exposure
You can still develop COVID-19 up to 10 days after you have been exposed.
- Wear a high-quality mask or respirator (e.g., N95) any time you are around others inside your home or indoors in public.
- Do not go places where you are unable to wear a mask. For travel guidance, see CDC’s Travel webpage.
- Take extra precautions if you will be around people who are more likely to get very sick from COVID-19.
Watch for symptoms
- fever (100.4°F or greater)
- shortness of breath
- other COVID-19 symptoms
If you develop symptoms
- isolate immediately
- get tested
- stay home until you know the result
- If your test result is positive, follow the isolation recommendations.
Get tested at least 5 full days after your last exposure
- Test even if you don’t develop symptoms.