According to Mayor Jeannette McCarthy's office, the West Nile virus has been detected in mosquitoes in Waltham.



However, no cases of humans contracting the virus in Waltham have been reported, the announcement said. The Massachusetts Department of Public Health notified the city at 12:30 p.m. on Thursday.



Spraying for mosquitoes will be done on Friday as a precaution, Waltham Health Director Walter Sweder told the Boston Globe.



For more information on avoiding the virus, click here.