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Overview of Arbovirus, Arenavirus, and Filovirus Infections


Thomas M. Yuill

, PhD, University of Wisconsin-Madison

Reviewed/Revised Jun 2023

Arbovirus, arenavirus, and filovirus are viruses that are spread from animals to people and, with some viruses, from people to people. The animal involved depends on the type of virus.


Arboviruses are arthropod-borne viruses. An arbovirus is not a single type of virus. Scientists apply the name arbovirus to over 250 different viruses from many different families of virus that are spread to people or animals by certain arthropods that feed on blood. Arthropods include insects (such as flies and mosquitoes) and ticks. At least 80 arboviruses cause disease in people.

Most arboviruses are transmitted by mosquitoes, but some are transmitted by ticks, one (Oropouche virus) is transmitted by midges, and others are transmitted by sand flies. Arboviruses are spread when an insect or tick bites an infected animal, then bites another animal or a person. Most arbovirus infections are not spread from person to person, perhaps because the amount of virus in human blood is inadequate to infect the arthropod vector. Exceptions include chikungunya disease and the flavivirus infections dengue Dengue Dengue is a mosquito-borne viral infection that causes fever, generalized body aches, and, if severe, external and internal bleeding (called dengue hemorrhagic fever). About 50 to 100 million... read more , yellow fever Yellow Fever Yellow fever is a mosquito-borne viral disease that occurs mainly in the tropics. Yellow fever occurs only in the tropical areas of Central Africa, southern Panama, and South America. Some people... read more , and Zika virus infection Zika Virus Infection Zika virus infection is a mosquito-borne viral infection that typically causes no symptoms but can cause fever, rash, joint pain, or infection of the membrane that covers the white of the eye... read more Zika Virus Infection , which can be transmitted from person to person by mosquitoes. Also, Zika virus can be spread during sexual activity. Uncommonly, dengue, chikungunya, and Zika viruses have been spread by blood transfusion or organ donation or from mother to newborn at birth. Casual, everyday contact has not been shown to transmit arboviruses from person to person.

Many arboviruses that were once present in only a few parts of the world are now spreading. These viruses include chikungunya virus, Crimean-Congo hemorrhagic fever virus, Japanese encephalitis virus, Rift Valley fever virus, West Nile virus West Nile Virus Infection West Nile virus infection is a viral disease spread primarily from mosquitoes to people. Most people have mild or no symptoms, but some people develop a severe infection that affects the central... read more , Ross River virus, and Zika virus. These viruses are spreading partly because climate change has resulted in more areas where the mosquitoes that spread the viruses can live. Also, travelers may be infected in areas where the virus is common, then return home and be bitten by a mosquito, which spreads the virus to other people.

Chikungunya virus is spread by a certain species of mosquito called the Aedes mosquito. This virus was first identified in Africa but has recently spread to the Caribbean and Central, South, and North America. Chikungunya virus infection typically causes a fever and severe joint pain, often in the hands and feet. Infected people may also have a headache, muscle pain, joint swelling, or a rash. Most people feel better within a week, but joint pan can persist for months or sometimes even years.


Arenaviruses are spread by rodents. Infections caused by these viruses include lymphocytic choriomeningitis Lymphocytic Choriomeningitis Lymphocytic choriomeningitis is a viral infection that usually causes a flu-like illness, sometimes with rash, joint pain, or infections in other parts of the body. Most people become infected... read more , Lassa fever Lassa Fever and South American Hemorrhagic Fevers Lassa fever and South American hemorrhagic fevers caused by arenaviruses are viral infections that cause bleeding (hemorrhage) and organ malfunction. They often result in death. These infections... read more , Bolivian hemorrhagic fever (caused by Machupo virus), Venezuelan hemorrhagic fever (caused by Guanarito virus), and Argentine hemorrhagic fever (caused by the Junin virus). Lassa fever can also be spread from person to person through contact with body fluids (such as saliva, urine, feces, or blood). Arenavirus infections are relatively common in people in some areas of the world and can cause severe disease.



  • Blood tests

  • Culture of blood or infected tissue

Polymerase chain reaction (PCR) techniques may be used to make many copies of the virus's genetic material. This technique enables doctors to rapidly and accurately identify the virus.

Tests are sometimes done quickly—for example, when the infection is a serious threat to public health or when symptoms are severe.

A sample of blood or other tissues is sometimes examined with an electron microscope, which provides high magnification with clear resolution.


  • Supportive care

  • Sometimes ribavirin

Treatment of most of these infections focuses on relieving symptoms and maintaining vital functions. For example, transfusions may be given if bleeding is severe.


Because there are so many different arboviruses, it is often easier and cheaper to control arbovirus infections by controlling the arthropods that spread them and preventing exposure to the virus (including preventing mosquito and tick bites) than by developing specific vaccines or drug treatments.

Controlling mosquitoes is difficult, but new approaches are being developed and tested. In addition to using chemical pesticides, scientists are genetically modifying mosquitoes, releasing sterilized male mosquitoes into the environment, or infecting mosquitoes with a bacteria that blocks virus infection in the mosquitoes.

Preventing exposure to a virus

Infections spread by mosquitoes or ticks can often be prevented by the following:

  • Reduce or limit infection in vector populations

  • Wear clothing that covers as much of the body as possible

  • Use insect repellants, such as DEET (diethyltoluamide)

  • Wear clothing that has been coated with the insecticide permethrin

  • Avoid exposure to the mosquito or tick as much as possible

For example, to help prevent mosquito bites, people can limit the time they spend outdoors in wet areas.

For ticks, the following can help:

  • Stay on paths and trails

  • Tuck trousers into boots or socks

  • Wear long-sleeved shirts (see sidebar )

Infections spread by mice or other rodents usually result from exposure to their urine, feces, or another body fluid, which contains the virus. The following can help prevent such exposure:

  • Before cleaning, air out closed spaces where mice have been.

  • Before sweeping or cleaning, wet surfaces with a solution that has 10% bleach.

  • Avoid stirring up dust.

  • Seal openings where rodents could enter homes.

  • Put food in rodent-proof containers.

  • Eliminate potential nesting sites around the home.

Prevention of exposure to Ebola or Marburg virus requires strict quarantine of infected people and use of isolation measures, because these viruses spread readily from person to person.


Drugs Mentioned In This Article

Generic Name Select Brand Names
Copegus, Moderiba, Rebetol, RibaPak, Ribasphere, Ribasphere RibaPak, RibaTab, Virazole
Acticin, Elimite, Nix Lice Killing Creme Rinse
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