Boston health officials reported Thursday afternoon that for the first time this summer, a sampling of mosquitoes has tested positive for West Nile Virus. The mosquitoes were found in Roslindale. No human cases of the virus have been detected so far this year.

“It’s again the time of year when it’s not surprising to find mosquitoes infected with West Nile Virus in Boston,” said Dr. Anita Barry, director the Infectious Disease Bureau at the Boston Public Health Commission. “The recent combination of hot weather and rain may have contributed to West Nile appearing slightly earlier this year than in some previous years, and people should take some simple precautions to avoid mosquito bites.”