The US Centers for Disease Control and Prevention (CDC) confirmed that XEC is a hybrid variant of KS.1.1 and KP.3.3, two strains of the Omicron lineage that cause Covid-19.

XEC was first recorded in Berlin, Germany, in late June before spreading to France, Denmark and the Netherlands, according to USA Today , citing data expert Mike Honey in Australia.

The XEC hybrid variant is also believed to have appeared in at least 25 US states.

While there is no indication yet that the XEC variant causes more severe Covid-19 disease, it could become the dominant variant due to its ability to spread as rapidly as variants in the Omicron lineage.

Fortunately, existing Covid-19 vaccines and boosters still provide protection for vaccinated people, experts say.

Like other respiratory diseases, Covid-19 and the recently emerged Omicron variants are expected to spread more widely in the fall and winter.

There is currently no indication that the XEC variant is associated with particular symptoms.

The CDC continues to list the basic symptoms of Covid-19, which can appear within 2 to 14 days after a person is exposed to the virus.

These symptoms include fever or chills, cough, shortness of breath, fatigue, muscle aches, headache, loss of taste or smell, stuffy or runny nose, dizziness or vomiting, diarrhea.