The New Jersey Department of Health is urging residents to take precautions against mosquito bites as mosquito activity increases across the state and West Nile virus has already been detected in mosquitoes in 12 counties this year.

Health officials, joined by the New Jersey Departments of Environmental Protection and Agriculture, said the best way to prevent mosquito-borne illnesses is to avoid bites and eliminate standing water where mosquitoes breed.

Residents are encouraged to use EPA-registered insect repellents, wear long sleeves and pants outdoors, stay in screened or air-conditioned areas when possible, and remove standing water from flowerpots, birdbaths, buckets, gutters, and other containers around their homes.

While most people infected with West Nile virus experience no symptoms or only mild flu-like illness, officials warned that some cases can become severe, affecting the brain and nervous system, particularly among older adults and those with weakened immune systems.

The Department of Health also reminded travelers visiting areas where dengue fever or malaria are common to take preventive measures before and after travel to reduce the risk of bringing mosquito-borne diseases back to New Jersey.

State officials said mosquito control efforts are ongoing statewide and urged residents to do their part by reducing mosquito breeding sites and contacting their county mosquito control agency if mosquito problems persist.