The summer is a wonderful time to go outdoors, but be wary of the array of dangerous bugs, insects, arachnids and myriapods. The list of insects that sting and bugs that bite is long, and tips on how to avoid them in the woods, on the trail or on your outdoor deck are simple. If you’re not careful, then you could find yourself on the wrong end of an attack — and what you think is the right thing to do may be the worst plan of all.

Serious problems with biting insects vary from region to region, said Lynn S. Kimsey, Ph.D., professor of Entomology and director, Center for Biosystematics, and director, Bohart Museum of Entomology. In general, pests become more active at a temperature above 60 degrees F/15 degrees C. "The warmer it is, the more active they are, and the more of them come out."

Wasps

Paper wasps and yellow jackets are not antagonistic insects in general unless their nest is traumatized. Stings hurt, no doubt, and pose a risk of allergic reaction for some. Paper wasps are a problem in the summer when they get big.

“Yellowjackets can be dangerous as we move into the later part of summer because they get aggressive, territorial and more intolerant, especially if you get close to their nest,” says Howard Russell, Entomologist, Department of Plant, Soil and Microbial Sciences at Michigan State University.

Bumble Bees and Carpenter Bees

Hikers and trekkers are likely familiar with the threat of bees. They are difficult to spot and, generally, will leave you alone if you leave them alone. But if you step on a nest, they will come out in force to defend their home. That’s when you need to get away as quickly as possible.

There is a risk of anaphylaxis or a deadly allergic reaction to a bee sting. It is rare, but some people are extra sensitive to bee stings. If you know you are at risk for anaphylaxis from a sting, you should be carrying your prescribed epinephrine auto-injector with you anytime you go outdoors during spring, summer or fall.

Hikers should throw a bottle of Benadryl into their bag when hiking. If you get stung and start to become itchy or have some hives appear, you can take some and mitigate your body’s histamine response.

Mosquitoes

Mosquitoes are prevalent in early summer, especially if there’s been plenty of rain, and common in the woods and near rivers. Their population decreases in warmer, drier weather. Mosquitos can carry several infectious diseases as well as viruses and parasites. Mosquito-spread diseases include malaria, Eastern equine encephalitis (EEE), West Nile virus, Zika, elephantiasis, Dengue fever and yellow fever are a few.

You can minimize the chance of mosquito bites by wearing long-sleeved shirts, long pants and socks; use EPA-registered insect repellent; and cover sleeping areas with mosquito nettings.

Black Flies and Fleas

Any New Englander will share stories of the seasonal black fly influx and their annoying behavior. Hats, long sleeve shirts and pants can be an effective defense against them, and their bites can cause swelling.

Fleas are more active as the weather gets warmer. When they bite, you won’t know it for a few hours, there will be several bites in a single area and it will likely promote itching. The bite site may appear like a red sore or bump. Typical flea bites tend to occur in the bend of an elbow, the back of the knee, at the waist, ankles and armpits. Avoid scratching to reduce the likelihood of infection.

Ticks

Ticks thrive in humidity. If you have a wet year, mild winter and early spring then you have ideal conditions for an increase in the tick population. Tick populations are growing across many parts of the U.S. and abroad in places like Europe, Africa, the Middle East, and Asia. That translates to higher possibilities of tick-borne diseases — most notoriously Lyme disease — and the need to be ever vigilant to spot these arachnids, often as small as a sesame seed, before they attach to you or another host in your household, like a child or a pet.

Consider using a tick repellent, especially if you’re going to be in the backcountry for a few days. It’s a good idea to apply insecticide permethrin to your gear and clothing as it will still remain protected after several washes (in case things get damp out there). You can also use repellent sprays on skin not covered by clothing — just be sure they’re EPA-registered repellents. 

Spiders

The black widow is really the most dangerous spider, but you are not very likely to come across it. The female black widow spider is known as the most venomous spider in North America. House spiders are the ones most likely to be hanging around the dark corners of your home in the spring. They are not considered a danger because they do not have venom strong enough to evoke much of a reaction. But a tiny spider bite can become a big problem. Spiders usually bite only if they feel threatened.

Millipedes and Centipedes

Large centipede bites may cause intense pain and discomfort for people, but fatalities are extremely rare. Although not generally considered dangerous to humans, many millipedes produce noxious secretions which, in rare cases, can cause temporary blistering and discoloration of the skin.

Prepare and Protect Yourself

The spring and summer seasons are a wonderful time to explore the outdoors — but be prepared to protect yourself against the dangers that may come with it. This means having the right attitude, the appropriate gear and a plan if the worst happens.

— Jeff Weinstein

Jeff Weinstein is a medical operations supervisor at Global Rescue, with 18 years of combined experience in emergency and disaster response, critical care paramedicine, and emergency management. With specialty training in austere medicine and mountain rescue from The School of Medicine at UNM and Advanced Wilderness Life Support (AWLS) from the Wilderness Medical Society.