As the weather warms and people begin to spend more time outside, ticks and mosquitoes will do the same. While these pests are annoying, even more than that, they can be a threat to our health.

As a medical entomologist, Associate Research Professor Lee R. Haines studies how insects spread diseases. Her research at the University of Notre Dame focuses specifically on the complex relationships between insects, the microorganisms living in their bodies, and the disease-causing agents they transmit to humans and animals

In five questions, Haines explains the risks mosquitoes and ticks pose to the Midwest and discusses how the public can best protect themselves and family members from these bloodthirsty pests.

When can people expect to see ticks and mosquitoes outside?

Ticks are hardier than mosquitoes so they are out now, and have been since it warmed up in February. The last one I removed (from myself) was in mid-November. In this part of the world, it would appear that we are at risk all year from ticks; if the ground warms up to 40-45 degrees, they become active.

Bloodthirsty female mosquitoes need it to be much warmer to start hunting us — they love the heat as much as most people do. In colder weather (below 60 degrees), mosquitoes cannot fly well, so the cool temperatures are a natural mosquito repellent. Enjoy your barbecues now!

Mosquitoes thrive in temperatures above 70. The hotter the better, because the warmer a water body becomes (think of your bird bath), the quicker a mosquito can grow from egg to adult. Buy your repellents!

Which insect-borne diseases are we at risk for?

Here in the Midwest, we are relatively lucky. We don’t have deadly mosquito-borne diseases like malaria, dengue fever or chikungunya fever … yet. If the winters continually get warmer, the more tropical mosquitoes that spread these diseases will continue their migration north as they already are doing.

In Indiana, the most common mosquito-borne disease is West Nile virus, but only about 15 serious human cases are reported per year. However, for horses and birds, especially corvids like ravens, crows and jays, it is more of a concern.

The other menace to our health comes from biting ticks, especially the black-legged or deer tick. This tick has a long life (roughly three years) and can transmit Lyme disease in all its life cycle stages. Since 2017, not only did more than 47 percent of adult ticks in St. Joseph County test positive for the Lyme bacteria, but also 356 people were diagnosed with Lyme disease. If Lyme disease is left untreated, it can cause severe, chronic health complications (such as arthritis and heart and neurological problems) in humans and animals.

A bite from a black-legged tick, and many other types of ticks, especially the lone star tick, can also cause an allergy to red meat called alpha-gal syndrome (AGS). Although thought to be rare in Northern Indiana for now, AGS causes a difficult allergy to live with as many goods contain meat products, including some types of vitamin gummies, desserts, tattoo ink and medications. Furthermore, the symptoms of AGS can be confusing as they range from delayed anaphylactic shock to irritable bowel-like syndrome, and consequently, it can take an average of 7.5 years to be diagnosed.

When shopping for insect repellent sprays, what should people look for?

What types of repellents and insecticides are available changes every year.

When using the gold standard “arm-in-cage” test, which involves putting a naked arm painted with bug repellent into a cage of ravenous female mosquitoes, it is clear that anything with 25-30 percent DEET was the most effective. DEET’s repellency power also lasts the longest — sometimes exceeding eight hours.

The good thing about DEET-based products is that they are also safe for use on young children (unlike lemon eucalyptus); just keep them away from anything plastic. DEET has a nasty habit of making plastic turn foggy like your watch face or phone screen protector!

There are other options should you want an alternative to DEET; look for products containing at least 30 percent oil of lemon eucalyptus, IR3535 or 20 percent picaridin, but be aware these products may have to be reapplied more frequently.

It is great to see that something like Consumer Reports exists, and its researchers have tackled this exact question.

Beyond sprays, what other insect repellent products and methods work best?

To have an evening on your porch with fewer ankle-biting mosquitoes, in addition to using repellents and assuming you don’t mind the smell of citronella, you could get some big citronella candles and place them on the floor so the scent and smoke curl around your feet. Better yet, sit downwind from a fan so it blows the smoke into the flight path of the upwind-flying mosquitoes hunting for human scents.

An interesting way to suppress mosquito numbers and other insects is to encourage a healthy population of mosquito-eating predators like bats and swallows near your home. Also, designing your gardens with plants that mosquitoes dislike (such as lemongrass, citronella and lavender) can also sometimes help — but if you have pets, be careful as often these kinds of plants are also toxic to pets.

What other advice do you have for avoiding ticks? And mosquitoes?

For ticks, be vigilant. Get into the routine of checking yourself and your pets after strolling outside near longer grass or through the woods, especially where there are fallen oak leaves. Ticks love hiding in them! Check also that your bug repellent is tick-approved (look for an EPA number) as many are only specific for mosquitoes and other biting flies.

For mosquitoes, in the summer it is very hard to avoid them, but you can lessen your chances of becoming dinner by employing a few strategies. Make sure there is no standing water (e.g., planters with water trays, bird baths, ponds) near where you want to relax at dawn and dusk. Such water is a beacon to females wanting to lay their eggs and then, after, in their hunger-crazed state, catch a meal.

Another way to dampen down your mosquito attractiveness is to avoid wearing dark colors, especially black. Stick to brighter colors—many mosquitoes dislike yellows and whites, regardless of their night-biting or day-biting preferences.

Contact: Brandi Wampler, associate director of media relations, 574-631-2632, brandiwampler@nd.edu