Two mosquito samples collected in Hyde Park and West Roxbury tested positive for West Nile Virus— the first positive samples in Boston this summer. Mosquitoes carry West Nile Virus, which spreads to humans through bites from infected mosquitoes. The risk of transmission is low, but on Tuesday the city urged residents to take precautions.

Mosquitoes carrying the West Nile virus have been identified in Oregon for the first time this year, according to the Oregon Health Authority.

The Utah State Public Health Laboratory has confirmed that sample from Cache County have tested positive for West Nile virus. There are abatement procedures in place and advice on what residents should do.