Arbovirus is a combination of the words anthropod-borne virus; anthropods, in this case, refer to mostly blood-sucking insects such as mosquitoes. The blood exchange brought about through a bite from an infected insect causes the release of virus particles into the host animals, potentially causing disease. Arboviruses, then, are not a single type of infection, but a group of viruses transmitted in the same way.
Features
Arboviruses are called zoonotic because they can cause disease when spread from animals to humans. According to Microbiology and Immunology On-Line (see Resources for more information), most of these viruses are pathogenic (disease-causing) in humans but not in insects. There are four major types of arbovirus: togaviridae, flaviviridae, bunyaviridae and reoviridae. All arboviruses are RNA viruses (having RNA as opposed to DNA as genetic material), and all but bunyaviridae are icosahedral (Microbiology and Immunology On-Line). Mosquitoes most commonly pick up arboviruses from birds but can also become vectors by feeding on small mammals.
Effects
Dhpe.org (Directors of Health Promotion and Education's website) reports four basic types of disease caused by arbovirus infection: diseases of the nervous system, fever, hemorrhagic fever, and arthritis with rash. Although most infected people do not experience symptoms, affected persons can experience very high fevers (hemorrhagic fevers cause unusual and potentially fatal bleeding), encephalitis (a condition in which the brain becomes swollen) and sometimes death.
Types
There are a number of arboviruses that cause disease in humans (although there are also many that do not). According to Microbiology and Immunology On-Line, arboviruses linked with encephalitis include La Crosse encephalitis and St. Louis encephalitis (and the related West Nile); dengue and yellow fever cause hemorrhagic fever; Colorado tick fever also causes muscle pain and a rash.
Geography
The distribution and infectiousness of arboviruses within an area's population of mosquitoes affects resulting arbovirus disease. Additionally, location will dictate which types of arbovirus will be in the population. In humans, who are otherwise so-called dead-end hosts for most arboviruses, the most serious arbovirus infections are the yellow and dengue fevers, found mostly in Africa and South America's tropical regions.
Prevention/Solution
According to dhpe.org, prevention of arbovirus infection is positively correlated with municipal mosquito-population control and individual precautions taken to avoid mosquito bites. As with other viral diseases, it is most commonly only possible to treat the symptoms; but, for instance, there exists a vaccine for yellow fever, to prevent infection.
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