Mosquito Bytes

 

1. Mosquito alert
2. Whining in your ear
3. Malaria
4. Illnesses expand (Dengue)
5. Death to mosquitoes
6. Climate change=more disease?
7. Advice for the weary (repellent pictured)
8.Stop already! (Q & A)

 

 

 

 

Meet breakbone fever
Breakbone fever is the delightful moniker for dengue fever, a viral infection that's found in 100 countries and causes half-a-million hospitalizations and thousands of deaths each year. 2 big-headed alien-looking creatures float below the surface of the water, clinging to the surface.

Aedes aegypti in the Pupal stage. These little aliens can grow up to be adult carriers of the dengue virus. Photo by CDC, courtesy of NIAID.

Dengue has been causing fever, chills, and skeletal pain for many years. After World War II, a more serious form of the disease -- dengue hemorrhagic fever -- emerged in Southeast Asia, where it became one of the leading causes among morbidity and mortality in children. This lovely item causes symptoms reminiscent of Ebola virus infection: bleeding from the nose, mouth, and gums, excessive thirst and difficulty breathing.

black and white patterned mosquito feeds on a mammalAedes aegypti, the mosquito that spreads dengue fever. © 1995 Leonard E. Munstermann.

Ominously, in the past decade or so, dengue hemorrhagic emerged in Latin America, reaching as far north as the Texas border. "What is happening now in Central and South America mirrors what happened in Southeast Asia," says Barry Beatty of Colorado State University, meaning that a new fatal disease is becoming established just south of the U.S. border.

There is no specific cure for either form of dengue, nor is a vaccine available.

Why is dengue on the march?

Unprecedented population growth, mostly in developing tropical countries, has resulted in enormous urban sprawl, and unsanitary housing, water, sewage and waste systems. The result has been more mosquitoes living closer to more people.Black and white patterned mosquito, engorged with blood

Pictured here, another member of the Aedes species, a female Aedes triseriatus, feeding. The CDC states: "The treehole mosquito (Aedes triseriatus) transmits the virus that causes La Crosse encephalitis." Courtesy CDC.

Changing life styles, in particular the spread of non-degradable plastic packaging, which makes ideal larval habitats for Aedes aegypti mosquitoes. Another factor is the dramatic increase in automobiles and discarded tires, which are equally useful to mosquito larva. These don't have to be large -- according to James Becnel of the U.S. Department of Agriculture, a few mosquitoes can breed in a bottle cap!

Increased commercial air travel is ideal for transporting dengue viruses (they travel inside their human victims) between population centers.

Finally, mosquito control methods used since 1970 have not reduced mosquito populations enough to control dengue.

"Collectively, these factors have been responsible for the global emergence of epidemic dengue/DHF [dengue hemorrhagic fever, the bleeding form of the disease] in the past 15 years," according to Duane J. Gubler, Director, Division of Vector-Borne Infectious Diseases at the Centers for Disease Control.

Microcsopic photo of the head and mouth parts of a female Aedes aegypti.
Microcsopic photo of the head and mouth parts of a female Aedes aegypti. Photo and © Dept. Bio., U. of Alberta. Courtesy BIODIDAC.

Dengue has been reported in 100 countries, among them the United States (Puerto Rico) and in Mexico, along the U.S. border. "With such a problem in Puerto Rico, there's a good chance that it could get here," says Becnel, and thus the need to find ways to reduce mosquito populations.

Handy. Time to talk about killing skeeters.

 

 

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