Mosquitoes are more than just nuisances. Philanthropist and businessman Bill Gates argues that these blood-thirsty bothers may be the world’s deadliest creature, spreading disease around the globe including West Nile virus in the Americas.
Mosquitoes are more than just nuisances. Philanthropist and businessman Bill Gates argues that these blood-thirsty bothers may be the world’s deadliest creature, spreading disease around the globe including West Nile virus in the Americas.
A mosquito bite is something to take seriously, said Michael Wimberly, senior scientist at the Geospatial Sciences Center of Excellence and professor of natural resource management at South Dakota State University.
Wimberly and colleague Michael Hildreth, mosquito expert and a biology and microbiology professor at the university, use data about weather conditions gathered from NASA satellites circling the Earth and about mosquitoes collected in traps on the ground to help mosquito control officers target West Nile virus-carrying insects in South Dakota communities — a U.S. hotspot for the disease.
“Although most people infected with the disease have no symptoms, a small percentage can develop severe illness that affects the central nervous system and can result in death,” Wimberly said. “Symptoms of severe illness include high fever, headache, neck stiffness, stupor, disorientation, coma, tremors, convulsions, muscle weakness, vision loss, numbness and paralysis.
“West Nile virus cases fluctuate greatly from year to year. For example, in 2011 there were only 712 cases reported, but in 2012 this number jumped up to 5,674 cases.”
How it starts
West Nile virus can be transmitted almost anywhere in the contiguous United States.
The possibility of contracting West Nile is especially high in certain parts of the country, including the Mississippi Delta and surrounding regions, the Great Plains and portions of California, Arizona and the Great Basin, Wimberly said.
There were over 2,000 cases of West Nile reported in 2017 with 121 deaths, according to the Centers for Disease Control and Prevention. More than 2,000 deaths in the U.S. have been attributed to West Nile virus since it was first reported in 1999 in Queens, New York.
Two different types of mosquitoes are the primary “vectors,” meaning they transmit the disease in the United States, Hildreth said. West Nile is primarily a bird disease, but mosquitoes who dine on infected birds can transfer it to humans.
“Many people assume that the primary determinant for whether there will be lots of West Nile virus human cases or very few is determined by the number of vector mosquitoes developing in a particular year, but actually the most important factor is whether the virus is amplifying in the birds,” Hildreth said. “We’ve had years when the vectors are very plentiful, and yet the virus never got a good start in the birds; in those years, human cases are down.”
Protect yourself
While the scientists continue their work predicting where West Nile virus will emerge to protect the population, consider these tips to protect yourself and your family:
— Use insect repellent and wear long-sleeved shirts and pants when outside in the evening — even when it doesn’t feel like mosquitoes are biting. Treat shoes and clothing with permethrin or buy permethrin-treated clothing and gear.
— Do not use insect repellent on babies younger than 2 months. Cover cribs, strollers and baby carriers with mosquito netting.
— Eliminate stagnant water that can serve as mosquito breeding sites, such as in tires, planters, buckets, flower pots and trash containers. Mosquitoes lay their eggs near water.