The new coronavirus variant XFG (also known as Stratus) causes hardly any different symptoms than earlier variants of the coronavirus. The symptoms also do not seem to be more severe. This is evident from a survey by the RIVM among participants in Infectieradar.

Just as much sore throat, less loss of taste Recently, media reports have suggested that XFG more often causes sore throats and more severe symptoms. The RIVM decided to investigate this using data from Infectieradar. Through Infectieradar, a large group of people reports symptoms consistent with a respiratory infection every week. This allows the RIVM to track the spread of infectious diseases. The RIVM has now compared the COVID-19 symptoms of two groups of participants in Infectieradar:

  • participants with a positive COVID-19 test from July to September 2025, when the coronavirus variant XFG was prevalent.
  • participants with a positive COVID-19 test from July to September 2024, when the coronavirus variant KP.3 was prevalent.

Data from Infectieradar shows that participants reported approximately the same amount of sore throat this summer as last year: 74% in 2025 and 71% in 2024. The number of symptoms reported by participants and how sick they felt was nearly the same. Participants reported an average of 7.8 symptoms in 2025 and 7.6 in 2024. Loss of taste occurred less frequently in 2025.

Hardly any different symptoms than before

Virologist and researcher Dirk Eggink (RIVM): “Sore throat is a common symptom of COVID-19, but occurs with the XFG variant no more frequently than with earlier variants. Reports of other symptoms, such as sneezing, coughing, and a runny nose, changed hardly at all. The severity of the symptoms was the same. There is no evidence that participants found the sore throat more severe.”