The JN.1 covid variant had a rapid spread through December 2023 and has now become the most common strain of the virus spreading in the continental United States, according to the US Centers for Disease Control and Prevention (CDC), increasing the total number of new cases and to a lesser extent hospital admissions. JN.1 cases are also increasing in the United Kingdom and France, in China and India, and in other European countries, as well as in our country.
Theodora Psaltopoulou, Professor of Epidemiology and Preventive Medicine at the School of Medicine of the University of Athens, the biologist Panagiota Zacharaki and the doctor Yannis Danasis summarize the latest data. International health authorities point out that it is not yet certain whether JN.1 infections cause different symptoms from other variants, with the CDC noting that «the types of symptoms and how severe they are usually depend more on a person's immunity and general health than on which variant is causing the infection.».
According to the CDC, symptoms of this subtype include: Cough, sore throat, headache, muscle aches, fever, loss of taste and smell, runny nose or nasal congestion, fatigue, brain fog, shortness of breath, and mild gastrointestinal symptoms (upset stomach, mild diarrhea).
The latest data from the UK Office for National Statistics, as of December 2023, suggests that the most commonly reported symptoms among respondents with covid-19 include: Runny nose (31.1%), cough (22.9%), headache (20.1%), weakness or fatigue (19.6%), muscle pain (15.8%), sore throat (13.2%), sleep problems (10.8%), restlessness or anxiety (10.5%).
Many of the most common symptoms, including runny nose and cough, have been reported in people with covid since 2020, although the list includes some new additions, such as sleep problems and anxiety. In addition, loss of taste and smell - once considered an indicative sign of covid - is now reported by only 2 to 3 per cent of infected people in the UK.
The sudden rise of JN.1 suggests that it is either more contagious or better at evading our immune system (immune evasion). However, based on existing data, it does not appear to be more aggressive than other circulating variants, according to the CDC.
Finally, the recommendations, worldwide, for the prevention and treatment of covid-19 remain the same: Stay cautious indoors and if you are positive it is best to stay at home, isolated from others for a few days. According to the US Centers for Disease Control, «it is important to know that existing vaccines and treatments still work well against the JN.1 sub variant, so this sub variant does not affect the CDC recommendations.».
