The Boston Public Health Commission said today that a Dorchester man had contracted West Nile Virus— the second confirmed human case in a Boston resident this year. The man in his 40s was hospitalized, but has been released. It is unclear at this time where he contracted the infection, which is carried by mosquitoes, according to city officials.

Mpst people who get the virus will never know it— as symptoms do not always manifest themselves in humans. However, in some cases people can become acutely sick.

“Just because fall is in the air doesn’t mean that we can stop worrying about mosquitoes yet,” said Dr. Anita Barry, director of the Infectious Disease Bureau at the Boston Public Health Commission. “Mosquitoes will continue to be an issue until the first hard frost, but fortunately, there are easy steps people can take to avoid getting bitten.”

Boston public health officials continue to remind residents to take simple precautions to reduce their risk of exposure to mosquitoes. These steps include using insect repellant when outdoors, especially from dusk to dawn when mosquitoes are more likely to be biting and, when possible, wearing clothing that includes long sleeves and pants. People can prevent mosquitoes from entering their homes by making sure that window and door screens are in good repair.

To help prevent mosquitoes from breeding, BPHC advises limiting places around the home where standing water can collect. People should turn over unused flower pots, buckets, wheelbarrows, and garbage cans; remove leaves and other debris that can clog gutters and trap water; dispose of or cover old tires; and cover swimming pools and kiddie pools when not in use.