Have plans to attend a Memorial Day BBQ this weekend? Along with the jean shorts and flip flops, you may have to break out mosquito repellant. Yes, along with the unofficial opening weekend of the summer season, this holiday is also the beginning of open season on a veritable mosquito feast in the form of, well, humans.
We spoke to Janet McAllister, Ph.D., an entomologist in the Division of Vector-Born Diseases at the Centers for Disease Control and Prevention, who gave us the lowdown on what's true and what's just hearsay. Read on for five of the biggest mosquito myths around, and tell us: What's your anti-mosquito battle plan?
All Mosquitoes Are More Or Less The Same
Most people, if they notice the difference between mosquitoes at all, assume that the difference is as minimal as, say, the difference between breeds of house cat. Not so, says McAllister.
"Those individual mosquitoes are actually different species and as different from each other as a lion is from a housecat," she says. "They have very different behaviors, very different preferences of what they want to eat and where they might live."
Where mosquitoes want to live is a big one: Urban species don't do well in the country and some species thrive only in one very specific region. What types of mosquitoes like your environment can have an effect on the types of diseases you're exposed to. What's more, only female mosquitoes bite humans.
All Mosquitoes Carry Disease
"There are over 3,000 mosquito species worldwide, but only a couple of hundred are important medically," says McAllister. That's because most species of mosquito don't even bite humans -- some prefer other animals like amphibians and reptiles.
The mosquitoes that do carry disease tend to be concentrated in specific species. For example, West Nile virus and St. Louis encephalitis virus -- two of the biggest public health threats -- come from the genera Culex. But that doesn't necessarily mean that Culex species of mosquito are the only insects capable of transmitting the viruses, explains McAllister. Instead, those species seem to be culpable for outbreaks of disease for reasons that scientists still don't fully understand.
A Dry Winter Means Fewer Mosquito Worries In The Summer
"It's true that mosquitoes breed in water, but actually, droughts are some of the most disease-promoting," explains McAllister. That's because the concentrated water, which is dirtier and more "richly organic," is particularly appealing to some disease carrying mosquitoes. What's more, the lack of water sources mean that mosquitoes and birds -- who carry many of the mosquito-borne illnesses that affect us -- are crowded together to share the resource, creating an environment rich for disease spread.
Mosquitoes Prefer People With "Sweet" Blood
While it's true that mosquitoes prefer to feast on some people over others, it has nothing to do with blood sugar, floral scents or many of the commonly perceived attractions.
"Different species have different cues for being attracted," says McAllister, though researchers have found that mosquitoes have in common a love of carbon dioxide, lactic acid and certain strains of bacteria that some people have in higher concentrations.
"Every individual is different: Some exhale more CO2, some sweat more," explains McAllister. What's more, anyone can make themselves more attractive to mosquitoes following heavy exercise, thanks to a potent combination of sweat, carbon dioxide and lactic acid.
Garlic Will Ward Off Mosquitoes
While there is some anecdotal evidence of people taking garlic pills or eating garlic to keep mosquitoes at bay, there is no scientific or clinical data to suggest that it helps.
Instead, choose an Environmental Protection Agency-registered spray or product, which has gone through extensive testing, to keep those mosquitoes at bay.