Two people from Mercedes and one from Weslaco have been confirmed to have West Nile virus, the leading mosquito-borne disease in the United States.
County health officials will begin vector control in the affected areas and are investigating whether any of these cases are travel-related, Hidalgo County Health and Human Services Director Eduardo Olivarez said Monday.
People typically get the disease after being bitten by infected mosquitoes and while there are no vaccines to prevent the disease or medicines to treat it, most people who get infected never even show symptoms of the disease, according to the Center of Disease Control and Prevention.
Symptoms of severe illness include high fever, headache, neck stiffness, stupor, disorientation, coma, tremors, convulsions, muscle weakness, vision loss, numbness and paralysis according to the CDC, but only one in five people ever develop symptoms, the county said in a news release.
One in 150 people may develop more serious symptoms and the disease can occasionally be fatal, the CDC said.
Olivarez said there are several preventive measures against getting bitten by infected mosquitoes such as applying repellent when going outdoors, wearing long sleeve shirts and pants when outdoors and getting rid of any standing water by frequently checking objects in the yard that can collect water including tires, buckets, planters and toys.
The county will release more information in a news conference set for Monday afternoon.