Wolbachia Bacterium Prevents Mosquitoes from Transmitting Zika and Chikungunya

2006
Prof. Frank Hadley Collins, Dir., Cntr. for Global Health and Infectious Diseases, Univ. of Notre Dame

This 2006 image depicted a female Aedes aegypti mosquito as she was obtaining a blood-meal from a human host through her fascicle, which had penetrated the host skin, was reddening in color, reflecting the blood’s coloration through this tubular structure. In this case, what would normally be an unsuspecting host was actually the CDC’s biomedical photographer’s own hand, which he’d offered to the hungry mosquito so that she’d alight, and be photographed while feeding. As it filled with blood, the abdomen became distended, stretched the exterior exoskeletal surface, causing it to become transparent, and allowed the collecting blood to become visible as an enlarging intra-abdominal red mass.

Dengue is a viral disease transmitted by urban Aedes mosquitos, principally A. aegypti, a species found living in close association with humans in most tropical urban areas. Mosquito biting activity is greatest in the morning for several hours after daybreak and in the late afternoon for several hours before dark. It may feed all day indoors, in shady areas, or when it is overcast. This mosquito breeds in artificial water containers, such as discarded tires, cans, barrels, buckets, 55 gallon drums, flower vases, and cisterns, all frequently found in the domestic environment. Since 1980, the incidence of dengue has increased dramatically in tropical countries worldwide, with endemic and/or epidemic virus transmission documented in most countries of the Caribbean Basin, Central and South America, the Pacific Islands, Asia, and Africa; many countries have had multiple outbreaks. Epidemics are frequently not reported because of inadequate disease surveillance.

Researchers at the University of Wisconsin–Madison have confirmed that a benign bacterium called Wolbachia pipientis can completely block transmission of Zika virus in Aedes aegypti, the mosquito species responsible for passing the virus to humans. Matthew Aliota, a first author of a paper published in the journal Scientific Reports, says the bacteria could present a […]