Second West Nile virus case reported in Massachusetts

Driving the news: A man in his 60s was exposed in Middlesex County, the Department of Public Health said.

• The first infection was reported last week, also in Middlesex County.

Threat level: The risk of virus exposure is now ranked high for Boston, Brookline, Cambridge, Everett, Newton, Somerville and Watertown.

• Older and immunocompromised people are at greater risk, says DPH commissioner Robbie Goldstein.

Zoom out: The state has detected 184 mosquito samples that tested positive for the West Nile virus this year.

Protip: State officials recommend draining standing water, where mosquitoes tend to lay their eggs, and installing window and door screens to keep mosquitoes out.