JN.1: The Fastest-Growing COVID-19 Variant

 

JN.1 is a heavily mutated, highly transmissible subvariant of omicron and an offshoot of BA.2.86, aka “Pirola.” It has an additional mutation that affects its ability to evade immunity. According to the U.S. Centers for Disease Control and Prevention, JN.1 now accounts for almost two-thirds of cases in the U.S. and may be “intensifying the spread of COVID-19 this winter.” The share of cases caused by JN.1 nearly tripled in the past month, and during a two-week period ending on Jan. 6, JN.1 accounted for about 62% of cases in the U.S. JN.1 was first reported in August 2023, and it has spread to at least 41 countries so far, according to the World Health Organization.

The variant’s growth comes as COVID hospitalizations rise, influenza continues to spread and RSV activity remains high in many places. Experts warn that the country may be facing its second-largest COVID wave, smaller than only the omicron surge in late 2021 and early 2022.

It’s not known whether JN.1 causes different symptoms from other variants, according to the CDC. The symptoms of JN.1 appear to be similar to those caused by other strains, which include:

• Fever or chills
• Cough
• Shortness of breath or difficulty breathing
• Fatigue
• Muscle or body aches
• Headache
• New loss of taste or smell
• Sore throat
• Congestion or runny nose
• Nausea or vomiting
• Diarrhea

It’s important to note that the type and severity of symptoms a person experiences usually depends more on a person’s underlying health and immunity rather than the variant which caused infection.

Testing is an important tool to protect yourself and others from COVID-19, especially ahead of indoor gatherings. All COVID-19 diagnostic tests — including rapid antigen tests and PCR tests — are expected to be effective at detecting JN.1, as well as other variants, according to the CDC.