With warm weather, school vacations, and a relaxing of Covid-19 restrictions, many of us in the Northern Hemisphere are joyfully returning to the great outdoors. This is good health advice for most of us; however there are hazards to be aware of ranging from the merely uncomfortable to the potentially life-threatening. I’ve highlighted some of the most common of these, organized by bites, stings, and rashes.

Bites

Mosquitos

In most cases, a mosquito bite is an itchy, temporary annoyance, easily treated with ice or a cold compress, menthol or aloe vera ointment, or an antihistamine if the bites are many and problematic. In temperate parts of the world, mosquitos don’t carry malaria; however they are a vector for the much rarer dengue fever, which causes high fever, headache and joint pains (but which affects fewer than 20,000 people annually in the U.S.). In all instances, prevention is the best form of treatment: carry and apply a topical repellent when in mosquito territory: the woods or anywhere near bodies of standing water. DEET, Picaridin, oil of lemon eucalyptus (OLE), Para-menthane-diol (PMD), and 2-undecanone are all EPA-registered repellents. Used as directed, EPA-registered insect repellents are safe and effective, even for pregnant and breastfeeding women. Long sleeves, pants, and socks can also help, although many mosquitos will bite right through clothing.

Ticks

Ticks are small blood-sucking insects that can carry a number of diseases—most notably Lyme disease and Rocky Mountain Spotted Fever.  Ticks are most active in warmer months—April through September in the Northern Hemisphere. They live in wooded and brushy areas with high grass and leaf litter—forests, woods, grassy hillsides, and even backyards. To prevent tick bites, walk in the center of trails, treat clothing and gear with repellent containing 0.5% permethrin, check your body for signs of ticks after being outdoors, including under the arms, in and around the ears, in the navel, on your back, around your waist, between your legs, and through your scalp. Showering within two hours of coming indoors is likely to wash off unattached ticks and is a good opportunity to do a tick check.

Removing a tick is straightforward: Grasp the tick as close to the skin’s surface as possible using fine-tipped tweezers. Pull outward with steady, even pressure. (Don’t twist or jerk the tick, which may cause the mouth-parts to break off while still embedded. If this happens, remove the mouth parts with tweezers, or if unsuccessful, leave it alone and let the skin heal.) Dispose of the tick by putting it in rubbing alcohol and flushing it down the toilet. Clean the bite area with rubbing alcohol or soap and water.

Symptoms of tickborne illnesses can vary, but most commonly include fever, chills, aches and pains—in other words, flu-like symptoms. However tickborne illnesses often also include a rash, some of which can be distinctive, providing an aid to diagnosis. If you have been bitten by a tick and develop these symptoms within a few weeks, see your physician for the best course of treatment.

Spiders

The most dreaded spider bite is that of the black widow, which is intensely painful. However another spider to be aware of is the brown recluse. Both tend to be found in dark, dry, and undisturbed environments, such as closets, attics, basements, and in wood piles. Both spiders are nocturnal and shy—hiding when they become aware of your presence. Black widows are approximately one-half inch across, typically black, with a characteristic red hourglass marking on their underbelly. Brown recluse spider are tan to dark brown with a violin-shaped marking on their back.

Symptoms of a black widow spider bite start within an hour of being bitten and typically include severe muscle cramps, abdominal pain, weakness and tremors. In severe cases, they may also include nausea, vomiting, dizziness, chest pain, and difficulty breathing.

Brown recluse spider bites may not even be noticed at first. If felt at all, victims might notice minor stinging as from a bee sting. Additional symptoms typically develop within eight hours and include intense pain and itching at the bite site, nausea, vomiting, and muscle pain. In severe cases, the brown recluse spider bite can cause blistering, blue discoloration, and necrotic lesions with scarring. However, the black widow spider bite can cause severe neurological symptoms especially in children or the elderly. Both types of bites require medical attention. In the case of a black widow spider bite, go to an emergency room, as clinics and physicians’ offices are unlikely to have antivenin on hand.

Rattlesnake

Rattlesnake bites are a medical emergency. Although rarely fatal, if left untreated the venom will destroy skin tissues and blood cells, causing internal hemorrhaging, which can result in organ failure and death. The venom takes only seconds to travels into your bloodstream, causing symptoms immediately. These will worsen over time if not treated.

Despite what you may have read, heard, or seen in TV westerns, the most effective treatment for a rattlesnake bite is a ride to the nearest emergency room that is supplied with antivenin. Call ahead so they’re ready for you. Do not “cut and suck” the venom out; do not apply a tourniquet; do not elevate the affected limb; do not waste time capturing the snake to confirm its identity. Instead, stay calm and get help. If you’re in a remote area without cell reception and are able to walk or ride out, do so. Ideally, you’ll reach an emergency room within 30 minutes of being bitten. If the bite is left untreated, your bodily functions will break down; however this requires a period two to three days. Remember that death by snake bite is rare. In most treated cases, people fully recover.

Of course, the best snakebite advice is prevention: be aware of your surroundings and keep a safe distance from a rattlesnake should you see one. Wear sturdy shoes and long, loose-fitting pants when traversing rattlesnake country.

Stings

Bees, wasps, yellowjackets, hornets, and ants

Bee, wasp, and hornet stings cause immediate pain and a red, swollen, and sometimes itchy area about ½- inch across. In some people, the area swells to a diameter of 2 inches or more over the next 2 or 3 days. Although stings are not generally dangerous in small numbers, they can cause anaphylactic shock and death to people who are allergic—and who should therefore carry an epinephrine injection device at all times. Milder allergic reactions can cause a rash, as well as itching all over.

Fire ant stings usually causes immediate pain and a red, swollen area, which disappears in less than an hour. A blister will form, rupturing in a few days, after which the area may become infected. In some cases, a red, swollen, itchy patch develops instead of a blister. Seizures may occur in people who have experienced a very high number of stings.

In the case of bee, wasp, and hornet stings, treatment consists of removing the stinger (scraping the area with a thin, dull edge such as a table knife or credit card works), applying ice and/or taking an antihistamine to reduce swelling, and soothing the area with calamine lotion, hydrocortisone cream, or a paste of baking soda and water. If pain persists, take an analgesic like acetaminophen. If you’re experiencing shortness of breath, or know you are allergic, take an epinephrine injection immediately or head to the ER.

In the case of fire ants, the treatment is the same, although you’ll first need to brush the ants off of you. Then wash the area with an antibacterial soap, apply ice and/or take an antihistamine to reduce swelling, soothe the skin with calamine lotion or and if pain persists, take a pain reliever like acetaminophen. If symptoms don’t improve within a few days, see your doctor to avoid a worse infection.

Rashes

Poison oak, poison ivy, and poison sumac

All three of these plants—poison ivy, poison oak, and poison sumac—contain an irritating oil called urushiol, which can trigger an allergic reaction when it comes into contact with your skin. The resulting itchy rash can appear within hours of exposure or up to several days later and can progress to oozing blisters lasting for a week or longer. If the oil is carried in smoke because of the plant being burned, the allergic reaction in the mucous membranes can be far more severe and may require a cortisone injection or prescription to control.

Otherwise, treatment is a cool bath with colloidal oatmeal and soothing over-the-counter treatments like calamine lotion. An antihistamine may also help.

The rash itself is not contagious; however, the oil that causes it can be picked up from clothing, animal fur, or gardening gloves or implements that have been in contact with the plant. So, if you’ve hiked through an area that contains poison oak, ivy, or sumac, shower and wash your clothes upon returning home; wash your dog; and wash any other items that might have the oils on them. Again, the best treatment is prevention: wear long sleeves and pants when hiking, know how to identify these plants and avoid them, and keep your pet from contacting them if possible.

Heat rash

Heat rash, which is also called prickly heat or miliaria, is very common—affecting more than 3 million people in the U.S. each year. It occurs when sweat pores are blocked, preventing the body from cooling itself via sweat. Symptoms range from superficial blisters to deep, red lumps, usually in skin folds and where clothing causes friction. In infants, the rash is mainly found on the neck, shoulders and chest. It can also show up in the armpits, elbow creases and groin.

The treatment for heat rash is to cool the body—resting in the shade or in an air-conditioned building, taking a cool shower or bath with colloidal oatmeal, drinking cool liquids. As with all of these hazards, the best approach is preventive: avoid over-exertion in the heat of the day; dress in cool, breathable, lightweight clothing; stay hydrated; tie a cool, wet cloth over your head or around your neck; take breaks when necessary.

None of this advice is intended to discourage you from heading outside. The benefits of outdoor rest and recreation are enormous, while the majority of these hazards are minor—and even the worst are fairly easily avoided. So put on your sunscreen and appropriate clothing, pack your mosquito repellent and EpiPen (if you’re allergic), and have fun out there!