Cases of norovirus, the common but highly contagious virus that causes gastrointestinal symptoms, are on the rise in the U.S., according to recent data from the US Centers for Disease Control and Prevention.

According to CNN, in the week ending February 17, more than 12% of tests for norovirus – a common and very contagious virus that causes gastrointestinal symptoms – came back positive, CDC data showed. That’s up from 11.5% the week before. Cases are particularly high in the Northeast, where more than 13% of tests came back positive. Positivity rates in the region have been over 13% since late January.