The California Department of Public Health (CDPH) is reporting increased West Nile virus activity across the state and is investigating numerous suspect cases in humans. While the first human case has not been confirmed by CDPH, a resident of Los Angeles County has symptoms consistent with West Nile virus disease. Initial tests on that patient indicate a probable West Nile virus diagnosis, which requires further testing for confirmation.
San Mateo County Mosquito and Vector Control District continues to find evidence of hantavirus infection in deer mice collected during routine rodent-borne disease surveillance. The most recent samples were collected during May and June of 2016 in the vicinity San Bruno Mountain and Montara.
The District continues monitoring for the presence of Aedes aegypti mosquitoes in Menlo Park. One method of monitoring is ovicups, small black plastic cups that are halfway filled with water. Inside the cup is placed a tongue depressor, wrapped with a brown coffee filter. This filter paper acts as an oviposition site for a female Aedes aegypti mosquito to lay her eggs. Once a week, one of the laboratory staff collects the paper-wrapped tongue depressors from the 14 ovicups in Menlo Park and 28 ovicups in cemeteries throughout the county. In th