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 […]

Free Articles Provide Insight on the Asian Tiger Mosquito, Aedes albopictus

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This week is National Mosquito Control Awareness Week, and the Entomological Society of America is supporting the effort with a special collection of articles about the Asian tiger mosquito. Like its close relative Aedes aegypti, the Asian tiger mosquito (Aedes albopictus) has been in the news recently due to its ability to transmit pathogens that […]

Scientists Track Mosquitoes that Transmit Zika and Dengue by County

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By Harvey Black As mosquito-borne diseases that were once rare or unseen in the United States are making their presence known in the country, a team of researchers from the Centers for Disease Control and Prevention and Colorado State University is calling for greater efforts to systematically map the presence of the vectors carrying these […]

Education, Mosquito Management Programs, and Cooperation Needed to Stop Zika, Dengue, and Chikungunya

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

This 2006 photograph depicted a female Aedes aegypti mosquito while she was in the process of acquiring a blood meal from her human host, who in this instance, was actually the biomedical photographer, James Gathany, here at the Centers for Disease Control.  The feeding apparatus consisting of a sharp, orange-colored “fascicle”, which while not feeding, is covered in a soft, pliant sheath called the "labellum”, which retracts as the sharp stylets contained within pierce the host's skin surface, as the insect obtains its blood meal. The orange color of the fascicle is due to the red color of the blood as it migrates up the thin, sharp translucent tube. Note the distended abdominal exoskeleton, which being translucent, allowed the color of the ingested blood meal to be visible.

DF and DHF are primarily diseases of tropical and sub-tropical areas, and the four different dengue serotypes (DEN-1, DEN-2, DEN-3, and DEN-4), are maintained in a cycle that involves humans and the Aedes mosquito. However, Aedes aegypti, a domestic, day-biting mosquito that prefers to feed on humans, is the most common Aedes species. Infections produce a spectrum of clinical illness ranging from a nonspecific viral syndrome to severe and fatal hemorrhagic disease. Important risk factors for DHF include the strain of the infecting virus, as well as the age, and especially the prior dengue infection history of the patient.

The Entomological Society of America (ESA) and Sociedade Entomológica do Brasil (SEB) held a Summit in Maceió, Alagoas, Brazil on 13 March, 2016 to discuss the Aedes aegypti mosquito, which is the primary transmitter of Zika, dengue, chikungunya, and yellow fever. While the Summit featured talks on many aspects of mosquito biology, behavior, and control, […]

A Report from the Summit on the Aedes aegypti Crisis in the Americas in Brazil

The Aedes aegypti mosquito is the primary carrier of the Zika virus. A new federal report offers new directions for research and development of mosquito-control efforts.

By Richard Levine Yesterday, March 13, 2016, nearly 70 scientists, public-health officials and other participants attended the Summit on the Aedes aegypti Crisis in the Americas, a one-day meeting convened by the Entomological Society of America (ESA) and the Sociedade Entomológica do Brasil (SEB) in the city of Maceió in Alagoas, Brazil. Although the Summit […]

The Aedes aegypti Mosquito Was a Problem Way Before the Zika Virus

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By Richard Levine Today I wrote a guest article for the Oxford University Press blog. What do Napoléon Bonaparte, Walter Reed, the Panama Canal, and the Zika virus all have in common? The answer is the Aedes aegypti mosquito, the primary vector of yellow fever, dengue, chikungunya, and the Zika virus. The ability to transmit […]

Free Resources on Aedes aegypti and Zika Virus Research

The Aedes aegypti mosquito is the primary carrier of the Zika virus. A new federal report offers new directions for research and development of mosquito-control efforts.

In response to the recent outbreak of the Zika virus in the Americas, Oxford University Press has curated a collection of free articles on the virus and its carrier, the yellowfever mosquito (Aedes aegypti), which is also the primary vector of yellow fever, dengue, and chikungunya. These articles are freely available to assist researchers, medical […]

International Entomologists to Collaborate on Controlling Zika, Chikungunya, and Dengue in Brazil

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Click here to read this in Portuguese. Click here to read this in Spanish. On March 13, 2016, in Maceió, Alagoas, Brazil, the Entomological Society of America (ESA) and the Sociedade Entomológica do Brasil (SEB) will host a gathering of the world’s entomological societies to discuss collaborative control options to combat one of the world’s […]

New Device Allows Chikungunya Test Results in an Hour

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By Ed Ricciuti Scientists at a U.S. Army research center have modified an assay that tests whether or not a sample of mosquitoes harbors the virus responsible for the disease known as chikungunya (CHIKV), long a problem in the Old World tropics but recently established in the Americas. They did not make the assay — […]

Some Facts About Florida’s Genetically Modified Mosquitoes

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By Richard Levine Over the weekend, a deluge of news articles about the possible release of genetically-modified mosquitoes in the Florida Keys swept the Internet. The modified mosquitoes, if approved, would be used to control mosquito populations without pesticides, and would lower the chances of Floridians being exposed to mosquito-borne diseases like dengue and chikungunya. […]