Asian tiger mosquitoes are an invasive species proliferating in the United States since 1985. Native to eastern and southern Asia, they were discovered near Houston, Texas, where they arrived in a used tire shipment from Japan or Taiwan. Asian tiger mosquitoes (Aedes albopictus) are now found throughout the Midwest and the eastern United States.
They Displace Native Mosquitoes
Asian tiger mosquitoes are about a quarter-inch long, easily identified by their white-spotted bodies and black-and-white-striped legs. They reproduce quickly in warm, moist environments, displacing the common native mosquitoes. Females can lay up to 300 eggs in a few weeks. They breed in tiny pockets of water found in tree holes, discarded tires, cans and other containers. Asian tiger mosquito eggs aren't harmed by cold or dry weather; they lie dormant, awaiting warm, moist hatching weather.
Their Bites Are Painful
Asian tiger mosquitoes may bite throughout the day, but they behave more assertively in early mornings and evenings. They deliver painful bites to birds, humans and other native mammal species, such as dogs, cats and horses. They're known to swarm in large numbers, acting aggressively when they're in a feeding frenzy. High concentrations of hungry mosquitoes make being outdoors difficult for humans and pets in infested areas.
Their Bites May Cause Allergic Reactions
Female Asian tiger mosquitoes need blood as a protein source necessary for egg production. After piercing a host's skin, she injects saliva into the bloodstream before drawing blood. This prevents the blood from clotting in her small food canal. Native animals, including birds and humans, suffer itchy, raised welts that may last a few hours or several days, depending on the severity of allergic reaction to the female mosquito's saliva in the host.
They Spread Disease
Asian tiger mosquitoes are carriers of many diseases and protozoa, such as West Nile virus, dengue fever, yellow fever, eastern equine encephalitis and canine heartworm disease. Large Asian tiger mosquito populations make it difficult to control and eradicate mosquito-borne diseases once they're introduced. Eastern equine encephalitis is carried from passerine birds to mammals by Asian tiger mosquitoes. Humans are rarely infected by eastern equine encephalitis, but it's prevalent among horses in areas where Asian tiger mosquito populations are established.
- CSA.com: Two Invasive Insect Species From Asia: The Asian Tiger Mosquito and the Asian Longhorn Beetle
- National Geographic News: Ferocious Tiger Mosquito Invades the United States
- North Carolina Museum of Natural Sciences: Asian Tiger Mosquito
- Maryland Department of Agriculture: The Asian Tiger Mosquito in Maryland
- Thomas Northcut/Photodisc/Getty Images