CANTON — Mosquitoes in Fulton County have tested positive for West Nile virus.

A pool of mosquitoes collected in Farmington have been confirmed as carrying the virus, county Health Administrator Katie Lynn said.

The mosquitoes were collected Friday.

West Nile is transmitted through the bites of infected mosquitoes. Only about 20 percent of people bitten by an infected bug experience symptoms, which tend to manifest between three days and two weeks after the bite.

Those symptoms can include fever, headache and body aches, though serious illness, including encephalitis, meningitis and death are possible. Those older than 50, or with compromised immune systems, are at the highest risk.