“When can we stop worrying about mosquito diseases?”
By Chris Williams on September 29, 2016.
If this question is about mosquito-transmitted diseases in general, the answer is “never.” There will always be blood-sucking mosquitoes that are carrying disease and they will always have the ability to infect people when they bite. We may be able to eliminate a particular mosquito disease with vaccines, insecticides, and diligence but be assured that another disease will surface somewhere in the world.
We’re Definitely Better Off Than Florida!
But I assume you’re wondering when mosquitoes will no longer be an issue here in the Northeast. Yes, we have spent an awful lot of time dealing with and worrying about mosquitoes this past summer. Fortunately, there will be an end to it, just not quite yet. Be glad that you don’t live in Florida (where Zika virus is an issue) or other parts of the southern U.S. where warm, wet weather may extend mosquito activity throughout the winter. In fact, climatologists say Miami has an average of 337 days a year of ideal mosquito weather.
The primary mosquito vector of Zika virus is a tropical mosquito and is not generally found this far north. But a second vector, the Asian tiger mosquito, is more cold tolerant and does occur in New Hampshire, Massachusetts and other New England states (see CDC Maps Give Updated U.S. Range for Zika Mosquitoes). So far, we have the mosquito but we have not had any locally transmitted cases of Zika virus in the Northeast.
Mosquito activity is tied to temperature and moisture (see When is Mosquito Season?). As long as temperatures remain warm enough, mosquitoes will be around although they may become somewhat less active as daytime temperatures fall. But if it remains warm and seasonal rains contribute standing water, mosquitoes can continue to breed. Since every state in the continental U.S. had above average temperatures this past summer, it seems likely that fall is going to also be warmer than normal for most of us.
Just a Few More Weeks for Mosquitoes
Generally, mosquito activity ceases once temperatures are below 50 degrees F. for an extended period. In our region, daytime highs will not be consistently below 50 until late October into mid-November. The Asian tiger mosquito will remain active as will other local mosquitoes that can transmit West Nile virus and other diseases.
Some mosquito species spend the winter as larvae or adults, hidden in protected areas. Here, the Aedes mosquitoes that transmit Zika virus will be spending the winter as eggs waiting to hatch in places that will be flooded in spring. For now, continue to dump standing water and use repellent in mosquito areas…spring and next year’s mosquitoes will be here soon enough!
Photo Credit : licensed under Public Domain