COVID-19 is notorious for its wide range of symptoms, some of which are quite unusual. With the emergence of a new variant, scientists have started noticing reports of a new symptom: night sweats.
The dominant strain causing a significant increase in cases worldwide is the subvariant BA.5, also known as the “sibling” of the Omicron variant. Together with BA.4, these two subvariants have become the most prevalent strains of the virus.
In the US, BA.5 currently accounts for approximately 65 percent of COVID cases, according to the CDC. This trend is mirrored in other parts of the world, including the UK.
Researchers believe that BA.5 may present with subtly different symptoms compared to other variants.
“One extra symptom from BA.5 I saw this morning is night sweats,” shared Professor Luke O’Neill, a Professor of biochemistry from Trinity College Dublin, in an interview with Irish radio station NewsTalk. “Isn’t that strange?” he added.
These subvariants are adept at evading the immune response, which means that individuals who have previously been infected with SARS-CoV-2 can still fall ill again. Fortunately, early evidence suggests that the BA.5 subvariant may cause less severe disease and death compared to previous variants like Delta. However, its ability to reinfect is a cause for concern.
The different symptoms associated with BA.5 are partially due to genetic changes in the virus and the way our immune system responds to the infection.
“The disease is slightly different because the virus has changed. There is some immunity to it – obviously with the T-cells and so on,” explained Professor O’Neill. “And that mix of your immune system and the virus being slightly different might give rise to a slightly different disease – with strangely enough – night sweats being a feature.”
Professor O’Neill also emphasized the importance of being fully vaccinated to minimize the potential impact of the infection.
There is limited data on how common the symptom of night sweats is. According to the ZOE COVID Study app, the most reported COVID symptoms among fully vaccinated individuals (two doses) include: runny nose, headache, sneezing, sore throat, and persistent cough. Other symptoms that were previously more prominent, such as loss of smell, shortness of breath, and fever, are now less commonly reported.
