The first human case of the West Nile virus this year has been confirmed, the D.C. Department of health announced Wednesday.

Last year, the District found six human cases of West Nile, an infection of birds that mosquitos can catch and pass on to humans. Cases have already been confirmed this year near Baltimore and in Prince George’s County .

The virus generally produces no symptoms in humans but at times can cause fevers, headaches and rashes.The elderly and those with weakened immune systems are more succeptible to infection.