The Test Sample
What is being tested?
Arbovirus (arthropod borne virus) testing detects viral infections that are transmitted from mosquitoes and other blood-sucking insects to humans. Found throughout the world, arboviruses are an important cause of viral meningitis and encephalitis. In temperate climates, they tend to cause occasional seasonal epidemics. In tropical climates, they may be found year-round, whenever mosquitoes are active.
There are hundreds of different arboviruses, but most are not common. The most widely recognized arbovirus in the U.S. is West Nile Virus (WNV). Some other less common ones include eastern equine and western equine encephalitis and St. Louis virus. Outside of the U.S., other arboviruses predominate in distinct but overlapping geographical regions. Two important ones are dengue fever and yellow fever. The Centers for Disease Control and Prevention (CDC) estimates that as many as 100 million people are infected with the dengue fever virus each year.
These viruses are spread when a mosquito, or sometimes another insect carrier (vector) such as a tick or sandfly, bites an infected bird or other small animal and becomes infected, then bites a human and passes it on. Arbovirus infections are not directly passed from person-to-person but can be passed from human-to-mosquito-to-human when the level of virus in the blood of the infected human is high. Rarely, an infection may be transmitted through a blood transfusion, organ transplant, or from a mother to child through breast milk.
Arbovirus testing is used along with a person's signs, symptoms, and history of exposure and travel to detect and confirm an acute arbovirus infection and to distinguish between an infection and other conditions that may cause similar symptoms. Testing measures either antibodies produced by the body's immune system in response to a specific arbovirus infection or it detects the virus's genetic material.
Depending on the virus causing the infection, people infected by an arbovirus may have only mild to moderate flu-like symptoms that resolve within a few days to a few weeks. In some cases, a sudden onset of high fever may be accompanied by a rash (dengue fever), jaundice (yellow fever), or severe joint pain and debilitating symptoms. Depending on the virus, a person may develop severe symptoms that may be life-threatening and require hospitalization.
Examples of arboviruses include:
|Virus/Illness||Insect Carrier||Found In|
|Eastern Equine Encephalitis (EEE)||Mosquito||Eastern U.S.|
|Western Equine Encephalitis (WEE)||Mosquito||Western U.S.|
|Venezuelan Equine Encephalitis (VEE)||Mosquito||South and Central America, rarely U.S.|
|Chikungunya Fever (CHIKV)||Mosquito||Africa, Asia, some in Southern Europe|
|Ross River Virus||Mosquito||Australia|
|Yellow Fever||Mosquito||South America, Africa, rare epidemics in U.S.|
|Dengue Fever||Mosquito||South America, Asia, Tropical tourist destinations, Caribbean|
|West Nile Virus||Mosquito||Throughout U.S.|
|St. Louis Encephalitis||Mosquito||Eastern and Central U.S.|
|Powassan Encephalitis||Tick||Eastern U.S.|
|LaCrosse Virus||Mosquito||South America, Central America, Asia, Central and Eastern U.S.|
|Rift Valley Fever||Mosquito, Tick, Sandfly||Africa and Middle East|
|Crimean-Congo Hemorrhagic Fever||Tick||Asia, Africa, Europe|
|Colorado Tick Fever||Tick||Europe, U.S.|
How is the sample collected for testing?
NOTE: If undergoing medical tests makes you or someone you care for anxious, embarrassed, or even difficult to manage, you might consider reading one or more of the following articles: Coping with Test Pain, Discomfort, and Anxiety, Tips on Blood Testing, Tips to Help Children through Their Medical Tests, and Tips to Help the Elderly through Their Medical Tests.
Another article, Follow That Sample, provides a glimpse at the collection and processing of a blood sample and throat culture.
Is any test preparation needed to ensure the quality of the sample?
No test preparation is needed.