If you’ve ever been to an outdoor party or BBQ in the middle of the day and not noticed an increase in mosquitoes, you’ve probably heard people complain about it. That’s because mosquitoes are selective insects, and some people are bitten more often than others.
There are several factors that can cause this to happen: In one study controlled by the Journal of Medical Entomology, bugs landed on people with blood type O almost twice as often as those with Type A. The researchers noted that this should be done. with the secretion we produce, which tips mosquitoes off in the blood type of people.
More research needs to be done on mosquitoes’ potential preferences for certain blood types over others, said Jonathan F. Day, a professor of entomology at the University of Florida. But he agreed that mosquitoes pick up on some cues that can make the bugs more likely to enter a particular person.
“That’s the cue to let them know they’re going to the blood source,” Day said. “Perhaps CO2 is the most important. The amount of CO2 produced, like people with a high metabolic rate – genetics, other factors – increases the amount of carbon dioxide they provide. The more you give, the more attractive you are to these arthropods.
But what separates us from non-living entities that emit carbon dioxide, like cars? Mosquitoes look for primary cues along with what Day calls “secondary cues.”
Lactic acid – the stuff that causes our muscles to cramp during exercise – is one secondary cue, for example. Lactic acid is released through the skin, signaling to mosquitoes that we are a target, Day said.
Mosquitoes also have other qualities that help them pick up secondary cues.
“Mosquitoes have excellent vision, but they fly close to the ground to avoid the wind,” Day said. “They can distinguish you from the horizon, so it’s very important about your dress. If you wear dark clothes, you will attract more attention because you will stand out from the horizon, while wearing bright colors will not be so much.
Mosquitoes also pick up “tactile cues” once they’ve landed on you.
“Body heat is a very important tactile cue,” says Day. “It plays with genetic differences or physiological differences. Some people tend to run a little warmer – when they land, they look for places close to the skin. That means people with a slightly higher temperature are more likely to get bitten.
Lifestyle or other health factors can also play a role, says Melissa Piliang, a dermatologist at the Cleveland Clinic.
“If your body temperature is higher, you are exercising and moving around, or if you drink alcohol, you are more attractive to mosquitoes,” said Piliang. “Being pregnant or overweight also increases your metabolic rate.”
One study showed that people who drank just one can of beer had a higher risk of mosquito bites than those who didn’t. Of course, drinking outside is a popular summer and fall activity.
“If you’ve been moving around all day doing yardwork and then stop around dusk and drink beer on the porch, you’re always at risk of getting bitten,” Piliang said.
How to Prevent Mosquito Bites
Just because you may be more prone to bites doesn’t mean they have to be inevitable.
“One of the best things is to avoid peak activity times (for mosquitoes),” Day said. “There are some species that are active during the day. They’re very selective. Sunrise and sunset are when you’ll see peak activity. Switching your morning run to an after-work run can help here.
Of course, this tip won’t help if you’re, say, throwing a BBQ for friends later that night. Try to cover as much skin as you can in that case, Day said, especially in areas or times when mosquitoes are most frequent.
“I like fishing shirts and long-legged outdoor pants that breathe, but keep out mosquitoes,” says Day. “Repellents that have a good protection time – defined as the time you apply when you get the first bite – are also good. About 5% DEET spray gives a full coverage of 90 minutes.
DEET is a common ingredient in insect repellents, and sprays with DEET are probably the way to go if you know you’re at risk of being bitten, Piliang said. Despite the controversy surrounding the health effects of DEET, a 2014 review by the Environmental Protection Agency again concluded that normal use of DEET products does not pose a health risk, including to children, pregnant women and breastfeeding women.
“DEET is the most effective,” says Piliang. “If you’re going to be in a place where mosquitoes are prone, knowing that they carry diseases is the best option. When you take a shower, put a little bit on it.” Always read the instructions on the spray before using it, and help children use the product by following the guidelines of the US Centers for Disease Control and Prevention.
And while you’ve heard that candles containing natural repellents like lemongrass oil can be helpful, there’s no research to back them up. Instead, keep the fan on or hang out in a cool place.
“Mosquitoes can’t walk,” especially in the wind, Piliang said. “You can run the fan to keep the air moving.”
If you end up with a bite, you might not even bother. “It all depends on how allergic you are to the chemicals in mosquito saliva, and it can vary based on the type of mosquito or how reactive you and your skin are to things in the environment,” Piliang said.
If it itches, the worst thing you can do is scratch it.
“When you do that, more histamine is released and it becomes itchy,” he says. “If you scratch, you’re also more likely to damage the skin. You can get bleeding, scabs and put yourself at risk of infection and scarring.
But there are some simple things you can do to relieve itching, such as applying ice cubes. “The cold sensation runs on the same nerve as the itch, so you can’t feel both at the same time,” Piliang said. “Even drinking it with ice will help relieve itching.”
If you have received several bites after the morning or evening outside, he is also recommended over-the-counter anti-itch cream with mild topical steroids like hydrocortisone. “You can apply it two to three times a day to reduce itching,” he said.
“And the last thing you can do if you’re really bit up is take an antihistamine,” he added. “Be able to fight that reaction.” While OTC types that make you drowsy — like Benadryl — are more common, you can take a non-drowsy antihistamine like Zyrtec or Allegra for daytime relief.
Of course, prevention is always better than cure, so use these tips to prevent bites in the first place when you head out for your remaining BBQs and tailgates. This article first appeared on HuffPost.
