Overview- Mosquito borne disease

In the late 1890s, scientists first discovered that mosquitoes transmit the parasites responsible for malaria. Since then, mosquitoes have been found to be vectors (an organism that transmits a disease) for a variety of diseases that afflict human populations all over the world. For much of the world, malaria is a constant threat. In the United States, the most common diseases carried by mosquitoes are encephalitides, inflammations of the brain that typically lead to a variety of symptoms specific to each disease, with fever, headaches and nausea commonly associates with most cases of an encephalitis.

Malaria

"I don't want for
this to scare ya
but my bunkmate's
got malaria"

Malaria is a disease caused by a plasmodium parasite. Five species of these plasmodium malaria parasites are known to infect humans, with varying degrees of severity. These parasites are transmitted from human to human via
Anopheles mosquitoes, most commonly Anopheles Gambia in Africa. Initial symptoms of malaria include fever, headache, and vomiting. In more severe cases of malaria, such as those caused by Plasmodium falciparum, coma and death are common if untreated. Even when treatment is administered, impaired development in children is common after severe malaria. Though no vaccine for malaria is currently available, treatment options are, though whether or not they are available and affordable in most areas impacted by malaria is another matter. According to the World Health Organization, more than half the world is at risk for malaria. According to the CDC, it accounts for a million deaths and between 350 and 500 million cases every year.
Did you know?
Prior to the discovery of penicillin, malaria was used to treat individuals with neural syphilis, and a Nobel prize was awarded to Julius Wagner-Jauregg in 1927 for the “discovery of the therapeutic value of malaria inoculation..”
Malaria Sources and Further Information
CDC Malaria Topic (http://www.cdc.gov/malaria/index.htm) – An extensive collection of malaria information and statistics
WHO 2008 World Malaria Report (http://apps.who.int/malaria/wmr2008/) - A report prepared by the World Health Organization on the impact of malaria and how to prevent it.
Wikipedia's Malaria (
http://en.wikipedia.org/wiki/Malaria) – A wikipedia article containing a variety of useful information on the life cycle of the plasmodium parasite as well as a variety of history and current research work on malaria.

Yellow fever

Yellow fever has caused hundreds of epidemics throughout history, decimating many cities and countries until the advent of a vaccine 1937. An acute viral disease with no real treatment, symptoms include fever, vomiting, nausea, chills, and back pain. In some cases of yellow fever, a second, more dangerous phase occurs leading to liver damage and bleeding from the mouth and eyes, with death a frequent result. Yellow fever occurs naturally in reservoir populations of monkeys in Africa, where it can be transmitted to humans via mosquitoes feeding first on infected monkeys, then on humans. Once those humans return to a more urban area, Aedes Aegypti and other Aedes species can transmit the disease easily between humans. The role Aedes Aegypti plays as a vector infecting humans has earned it the common name of “Yellow fever mosquito.” An effective vaccine has greatly reduced the prevalence of the virus, though the WHO reports an increase in cases over the last few decades, raising concern unvaccinated areas may be at risk for future epidemics.
Did you know?
In 1793, a Yellow Fever Epidemic ravaged Philadelphia, causing the U.S. Government, and President George Washington, to flee what was then the capital of the country.
Yellow fever Sources and Further Information
WHO | Yellow Fever (http://www.who.int/topics/yellow_fever/en/) - Yellow fever information and resources from the World Health Organization
CDC Yellow Fever (
http://www.cdc.gov/ncidod/dvbid/yellowfever/index.html) – The CDC's Yellow fever homepage.
Yellow Fever in Philadelphia (
http://www.eyewitnesstohistory.com/yellowfever.htm) – An eyewitness account of Yellow fever in Philadelphia in 1793.

West Nile Virus

West Nile virus, which causes an encephalitis of varying severity in humans, was first isolated in 1937 in Africa, though it had undoubtedly existed in Africa for some time. It was not until 1999 that the virus gained widespread attention in America when an outbreak occurred in New York City, rapidly spreading to neighboring states, then eventually throughout the country and into the rest of North America, the Caribbean, and Central America. While the majority of individuals infected by West Nile virus are asymptomatic (leading to vast underreporting), symptoms typically include fever, headache, weakness, drowsiness, joint pain, and other flu-like symptoms. Severe cases of West Nile virus lead to dangerous encephalitis combining the typical symptoms with severe decreases in consciousness and fatigue, sometimes resulting in death. According to the CDC, a total of 1356 cases of West Nile virus were reported in 2008, with 44 deaths. This is down significantly from the 2007 numbers of 3630 reported cases and 124 fatalities. Culex species (Culex quinquefasciatus in the South, Culex tarsalis in the Midwest/West, and Culex pipiens in the Northeast) are the most common vector in the United States, though West Nile has been isolated from other mosquito species as well.

Did you know?
Researchers now think that West Nile virus is a good candidate for the disease that killed Alexander the Great in 332 B.C.
West Nile virus Sources and Further Information
CDC West Nile virus (http://www.cdc.gov/ncidod/dvbid/westnile/index.htm) – The CDC's website for West Nile virus, including graphs and figures for reported cases since West Nile virus reached the U.S.
Alexander and West Nile Virus (
http://www.cdc.gov/ncidod/EID/vol9no12/03-0288.htm) – A historical review indicating that Alexander the Great may have died of West Nile Virus.
West Nile virus at Wikipedia (
http://en.wikipedia.org/wiki/West_Nile_virus) – A wikipedia article on West Nile virus.

La Crosse Encephalitis

The La Crosse virus was first isolated from a young girl in La Crosse, Wisconsin, in 1963. Symptoms are typical for an encephalitis, including nausea, headache, and vomiting, and rarely brain damage, seizures, coma, and paralysis. Severe La Crosse can be fatal, as no specific treatment exists, and even if a patient survives a severe case of the disease, permanent side effects such as impaired development are a possibility. The primary vector of La Crosse encephalitis is the mosquito Aedes Triseriatus. La Crosse is vastly under-reported since the majority of cases are not severe enough to require special treatment. Only 70 cases are reported per year on average, with under 1% fatality rate. La Crosse was primarily found in the Midwestern area of the United States. Recently, however, it has been found in the Appalachian region and is on the rise in the Southeastern United States.
Did you know?
It is believed that La Crosse expanded it's range due to the fact that introduced species, Aedes Albopictus, (Yes, the species the Labor Day Mosquito Count is trying to track!) is a very efficient vector of the virus.
La Crosse Sources and Further Information
La Crosse Fact Sheet (http://www.cdc.gov/ncidod/dvbid/arbor/lacfact.htm) – CDC La Crosse Fact Sheet
Naturally Infected Albopictus (
http://www.cdc.gov/ncidod/eid/vol7no5/gerhardt.htm) – An article from Emerging Infectious Diseases on the first wild caught Albopictus with La Crosse.
Wikipedia's La Crosse Article (
http://en.wikipedia.org/wiki/La_Crosse_encephalitis) – A Wikipedia article on La Crosse encephalitis.

Dengue Fever

Another virus transmitted by Aedes Aegypti and Aedes Albopictus, Dengue Fever or Dengue Hemorrhagic Fever is found widely throughout the tropics. Symptoms include painful joint pain, severe fever and headache, and a rash characterized by bright red spots appearing on the chest and lower limbs, occasionally spreading to cover the entire body. Unlike many other viruses, infection by one type of Dengue greatly increases the risk of further, more severe infections. Some cases can rarely lead to dengue shock syndrome, which causes circulatory collapse, abdominal pain and hemorrhage and has a mortality rate ranging from 6 to 30 percent. There is no specific treatment for Dengue fevers, and instead relies on supportive treatments to keep patients hydrated. Dengue is considered a disease on the rise, with over 2.5 billion people living in with high risk of transmission. The WHO estimates over 50 million Dengue cases worldwide each year.
Did you know?
Dengue fever is thought to have been first recorded in a Chinese medical encyclopedia from the Chin Dynasty, where it was described as a 'water poison' having to do with flying insects.
Dengue Fever Sources and Further Information
WHO | Dengue/DHF (http://www.who.int/csr/disease/dengue/en/) - The World Health Organization's Dengue fever page.
Wikipedia's Dengue fever (
http://en.wikipedia.org/wiki/Dengue_fever) – Wikipedia's article on Dengue, including history and prevalence of the disease.
Definition of Dengue (
http://www.cdc.gov/ncidod/eid/vol12no06/pdfs/etymology.pdf) – An excerpt from the publication Emerging Infectious Disease with a definition of Dengue.

Other Mosquito Borne Diseases

The above are but a few of the many diseases carried by mosquitoes. Provided below is a short list of other diseases carried by mosquitoes, as well as links to WHO and CDC articles on each.
Chikungunya -
Japanese Encephalitis -
Eastern Equine Encephalitis -

John Soghigian, MA student, Clark University