Mosquitoes: The World’s Deadliest Creatures

Buzzzzz, smack! Buzzzzzzz, smack, smack!!

Does this sound familiar – just as you are drifting off to sleep, a mosquito awakens you with its distinctive high-pitched sound buzzing in your ear? That noise is the insect beating its wings 800 times per second, creating a vibration that alerts our senses.

As you exhale at night, the carbon dioxide you emit sinks along your ears and pillow. This, coupled with your body heat, alerts mosquitoes that a blood meal is nearby. An interesting fact: female mosquitoes bite, but males don’t. The females have a special receptor that can detect carbon dioxide as far away as 150 feet. They swoop in, targeting their mammal host for the iron-rich blood needed to develop their eggs. After securing blood, females lay their eggs in still water – sometimes right in your backyard (in a bird bath, a stagnant pond, or even a flowerpot containing water). Eggs usually hatch in 24 to 48 hours.

The mosquito is widely regarded as the world’s most dangerous animal, because various breeds carry viruses and parasites that can be transmitted to humans as the female bites. Dengue, yellow fever, Japanese encephalitis, chikungunya, malaria, and the Zika and West Nile viruses are just some of the diseases and viruses that mosquitoes transmit. Many of these diseases are prevalent in tropical and subtropical regions of the world, and they account for more than a million deaths and more than 700 million infections every year. Some can cause birth defects or lifelong illnesses.

The spread of mosquito species that carry these diseases is increasing due to travel and globalization as well as urbanization, which allows for fewer natural predators of mosquitoes and more hard surfaces where water can accumulate for breeding and egg hatching. In addition, the rise in global temperatures is allowing for longer breeding and disease transmission seasons.

Buzzing About World Mosquito Day

Breakthroughs in research about mosquitoes date to 1897, when Sir Ronald Ross discovered that the female Anopheles mosquito carries the parasite that causes malaria. Sir Ronald, a British doctor, was later awarded the Nobel Prize for his research. Now, World Mosquito Day (observed annually on August 20) commemorates that discovery, with prominent health institutions highlighting programs designed to educate the public about mosquito-borne illnesses. If you are planning to travel to regions where these diseases are most prevalent, consult your local health department, which offers advice and vaccines to help prevent transmission. For example, vaccines are available for yellow fever and Japanese encephalitis.

We all need to be more vigilant about stopping the spread of mosquito-borne diseases. Wear long-sleeved shirts and pants to help prevent bites, especially in the early morning and sunset hours, and use mosquito repellent. Empty any standing water around your home, and if you have fountains or birdbaths, either keep the water moving or use a mosquito larvicide that kills larvae (also called wigglers). Repair torn patio, door, and window screens to help keep mosquitoes out of your home. And support vaccine and education campaigns designed to lessen disease transmission.

Patricia Wilson moved to Orlando in 1990 and since then has been involved in understanding the science of Florida’s unique environmental issues. She has volunteered with NOAA’s Marine Microplastics Program and has worked with the American Association of University Women to develop a free educational program about how simple choices that we make can help improve water quality.