State health officials have confirmed Maryland's first cases of West Nile virus this season.

All three of those infected by the virus passed to humans by mosquitoes were adults in the Baltimore area, according to The Maryland Department of Health and Mental Hygiene. The agency did not provide further details about the victims.

West Nile has also been detected in mosquito pools in Montgomery and Worcester counties.

Fever, headache, body aches, skin rash and swollen lymph glands are symptoms associated with the virus, but most infected people show no symptoms. Less than 1 percent of people will have more severe symptoms such as disorientation, coma and  tremors. In rare cases people die from the virus.

People older than 50 and whose immune symptoms are compromised have higher risk of West Nile infection.