We’re putting mosquitoes at the top of the list not just because they are the most common, but because they are the most dangerous. In fact, mosquitoes are the most deadly animal on Earth, responsible for millions of deaths each year, according to the Illinois Department of Public Health.
The vast majority of mosquito-related deaths are due to malaria, which kills between 2 million and 3 million people a year and infects more than 200 million people a year, IDPH reports. While malaria does sometimes occur in the United States, it isn’t common. But that doesn’t mean we are safe from mosquito-related illnesses, including those that can be deadly.
In the United States, the risk of contracting encephalitis from a mosquito is much greater than the risk of getting malaria, according to IDPH. Among the viruses transmitted by mosquitoes in Illinois are West Nile virus, which is a form of encephalitis; St. Louis encephalitis; La Crosse encephalitis; Eastern equine encephalitis; and Western equine encephalitis.
Illinois is home to two kinds of mosquitoes, Culex and Aedes, both of which can transmit diseases to humans. Culex mosquitoes typically bite at dusk and dawn, IDPH reports. They lay their eggs in natural and man-made sources of standing water, including small ponds, pools, bird baths, buckets and clogged gutters. The eggs won’t develop in running water or in water that has been present for less than a week, so it’s important to keep your yard free of these sources of standing water.
Aedes mosquitoes include both nuisance mosquitoes and disease-transmitting mosquitoes, such as inland floodwater mosquitoes, Asian tiger mosquitoes and tree hole mosquitoes. Inland floodwater mosquitoes are typically the first mosquitoes we see in the spring, and again later in the season after heavy rains. They typically bite in the late afternoon and into the dark hours, but they can bite at any time if they are in shady areas with a lot of vegetation.
Mosquito-borne illnesses are spread by mosquitoes when they bite an animal, typically a bird, that is infected with the virus and then bite other animals, including humans, the health department reports. Many people who become infected with these viruses do not develop symptoms. In the case of West Nile virus, 80% of humans have no symptoms of infection, but others may develop a flu-like illness that in rare cases can cause life-threatening complications.
The best way to prevent mosquito bites is to avoid the bugs altogether, although that isn’t always practical. If possible, plan time outdoors around the most active times for mosquitoes, namely dusk and dawn. And if you are spending time outdoors during those peak times, use mosquito repellent.
DEET is the gold standard when it comes to repellents. Look for products containing 20 percent to 30 percent DEET to provide the best protection. Other active ingredients that can repel mosquitoes are picardin, which doesn’t have as strong of an odor and isn’t as sticky as DEET, and lemon oil of eucalyptus, which is derived from a plant but doesn’t last as long as DEET or picardin and should not be used on children. Always read and follow all label directions with any repellent you use, IDPH advises.