Officials say mosquitoes still pose threat in region
Health officials say disease-carrying mosquitoes still pose a threat in the region. At left is Culex pipiens, also known as the northern house mosquito, the species mainly responsible for transmitting the West Nile virus to humans. At right is Aedes vexans, also called the floodwater mosquito and considered primarily just a nuisance. (AP File Photo) Purchase photo reprints »
Health officials say disease-carrying mosquitoes still pose a threat in the region, despite a noticeable drop in their presence in recent days.
The reminder comes a few weeks after the state Department of Public Health increased the risk level to high from moderate for exposure to West Nile virus and Eastern equine encephalitis in many Valley communities.
The warning urged residents to take extra precautions to avoid mosquito bites, especially at night.
“I believe people should continue to be as concerned as they were earlier,” said Jackie Duda, health agent in Easthampton.
Amherst Health Director Julie Federman said the DPH is unlikely to lower the alert level right now, especially given a steady rise in the number of EEE and West Nile cases statewide.
“There is nothing that indicates the risk is going down until the first hard frost,” Federman said.
Public health efforts have been complicated by the fact that two mosquito-borne diseases are involved, calling for different responses. Some communities, like Amherst, canceled or rescheduled outdoor evening activities because of the EEE threat. Other communities, like Northampton, were cautioned about West Nile virus but not advised to reschedule evening activities.
Merridith A. O’Leary, health director in Northampton, said that even though it wasn’t required to do so, the Northampton school department opted to move evening athletic events to the daytime for about three weeks in response to the mosquito threat. As of this week the district began allowing nighttime activities again.
“The towns are so close there was just confusion over what we were at high risk level for,” O’Leary said of the decision to cancel evening events in Northampton schools.
She said she has encouraged coaches and other leaders of youth organizations that have events outside at night to make sure players who are sitting idle cover exposed skin.
Until the threat level goes down, Amherst will continue to reschedule or cancel night events, Federman said.
“That will remain in effect unless we receive other indications from the state,” she said.
Until the first frost, residents are advised to continue to follow a series of recommendations spelled out by the DPH. This includes limiting evening activities between dusk and dawn, covering exposed skin when outside, and using insect repellent with DEET. Dusk now begins at 6:25 p.m.
A hard frost, often referred to as a killing frost, occurs when temperatures fall below 28 F for more than two hours, O’Leary said.
That likely won’t happen this week. Local weather forecasts predict that nighttime temperatures will remain above freezing through at least Sunday.
“The cooler weather has definitely slowed the breeding of mosquitoes, but there are still mosquitoes out there,” O’Leary said.
Federman cautions that older mosquitoes tend to carry diseases at higher rates, meaning the risk is still prevalent.
Hampshire County communities deemed at high risk for exposure to West Nile include Northampton, Easthampton, Southampton, Hadley, South Hadley and Granby.
The designation was prompted by an increase in the number of confirmed cases in the surrounding area, including a Hampden County resident who was hospitalized. Statewide, there have been 20 human cases of West Nile virus compared to six cases a year ago, the DPH said.
All those communities remain in the high risk category for West Nile, according to the DPH. Such a designation does not trigger a recommendation that they cancel outdoor evening events.
Communities deemed at high risk for exposure to EEE, however, including Amherst, Granby and Pelham, have been advised to cancel outdoor events at night.
Those communities are on high alert after a horse stabled in Belchertown tested positive for the disease. The state has declared Belchertown at critical risk for EEE.
EEE is more dangerous to people of all ages than West Nile and has a higher fatality rate, Federman said. West Nile tends to affect people 50 and older.
There have been seven human cases of EEE statewide, three of which resulted in death, and five cases of the disease in horses.
Federman said the threat level likely won’t be reduced until the first hard frost because the state does not conduct mosquito pool testing in western Massachusetts. Such testing, which involves collecting mosquitoes and testing them for diseases, is more prevalent in eastern Massachusetts, she said.
Easthampton, meanwhile, did not alter its high school athletic schedule because it does not have night games, Duda said. Other organizations continue to limit nighttime activity, she said.
Duda said that even though public concerns about mosquitoes may be diminishing, people should remain vigilant until the first frost. In addition to covering up and wearing insect repellent, she said, they should eliminate standing water on their property and fix screens that may have holes in them.
“People do tend to have an upwelling of concern about any public health issue when it’s announced,” Duda said. “Over time, the concern wanes. That might be what we’re seeing here.”