As COVID Omicron BA.5 continues to spread in the US, some may be wondering if the variant might cause distinct symptoms that set it apart from other Omicron variants.
BA.5 is a sub-type of the Omicron variant of COVID that has been spreading around the country for months. Since it first started appearing in significant numbers in May, BA.5 has become by far the dominant COVID variant in the country and accounted for an estimated 77.9 percent of sampled cases in the week ending July 16, according to projections from the US Centers for Disease Control and Prevention (CDC).
The number of COVID cases in the country has been increasing in recent days, too. Two weeks ago on July 7, the seven-day moving average of new cases was just over 107,000, CDC data shows. By July 19, it was 126,000.
Scientists think that BA.5 is even more transmissible than the already highly-infectious earlier forms of the Omicron variant. However, there are still many unknowns, such as whether or not it causes more severe disease.
There have been reports that BA.5 might be causing slightly different symptoms from earlier Omicron types.
Professor Luke O’Neill from Trinity College Dublin told an Irish radio station recently that “one extra symptom from BA.5 I saw this morning is night sweats,” according to British newspaper The Independent.
In addition, Dr. Julianne Burns, a pediatric infectious disease specialist at Stanford Children’s Health in California, told Business Insider that “gastrointestinal symptoms can be more common in children.”
Other sources say the symptoms of BA.5 are similar to those of previous Omicron sub-variants. UC Davis Health stated that they all cause symptoms such as runny nose, cough, sore throat, fever, headaches, muscle pain, and fatigue.
In addition, it can be particularly hard to tell if one variant is causing particular symptoms in a region where multiple variants are circulating.
Alicia Matheson, a spokesperson for the ZOE COVID study in the UK that tracks COVID symptoms over time, told Newsweek: “As the three variants BA.2, BA.4 and BA.5 are co-existing at the moment, we can’t currently provide insights on a specific variant and its symptoms until one variant becomes dominant.”
She shared data tables showing the top 20 symptoms reported from several thousand study contributors who tested positive from July 14 to July 21. They showed the top five symptoms were sore throat (58.51 percent); headache (48.7 percent); cough with no phlegm (42.19 percent); blocked nose (41.62 percent); and running nose (40.97 percent).
The top five symptoms from the previous week were almost identical: sore throat (57.74 percent); headache (49.46 percent); blocked nose (40.37 percent); cough with no phlegm (40.03 percent); and running nose (39.6 percent).
Still, it is known that the main symptoms of COVID seem to change over time. For example, reports from South Africa in the early days of Omicron back in late 2021 indicated that patients there still had severe fatigue but no loss of taste and smell according to Yale Medicine—one of the tell-tale signs of COVID in the early days of the pandemic.
Indeed, ‘loss of smell’ was reported by just 11.55 percent of people in the July 14-21 ZOE dataset.
Meanwhile, one crucial characteristic of BA.5 that scientists are investigating is its ability to dodge vaccines. It’s still being looked into, but CDC Director Rochelle Walensky said at a press briefing on July 12 that “we know that vaccine effectiveness against severe disease and death remains high for other Omicron sub-lineages and likely also for BA.4 and 5.”