Merck Manual

Please confirm that you are a health care professional

honeypot link

Overview of Arbovirus, Arenavirus, and Filovirus Infections

By

Thomas M. Yuill

, PhD, University of Wisconsin-Madison

Last full review/revision Aug 2021| Content last modified Aug 2021
Click here for Patient Education
Topic Resources

Arbovirus (arthropod-borne virus) applies to any virus that is transmitted to humans and/or other vertebrates by certain species of blood-feeding arthropods, chiefly insects (flies and mosquitoes) and arachnids (ticks). Arbovirus is not part of the current viral classification system, which is based on the nature and structure of the viral genome.

Families in the current classification system that have some arbovirus members include

  • Bunyaviridae (comprising the bunyaviruses, phleboviruses, nairoviruses, and hantaviruses)

  • Togaviridae

  • Flaviviridae (comprising only the flaviviruses)

  • Orthomyxoviridae (comprising the thogotoviruses)

  • Reoviridae (comprising the coltiviruses and orbiviruses)

  • Togaviridae (comprising the alphaviruses)

Pearls & Pitfalls

  • Arbovirus is not a family of viruses; the term indicates only that a virus is transmitted by certain species of arthropods—arthropod-borne virus.

  • Members of many different viral families may be arboviruses.

Arbovirus species number > 250 and are distributed worldwide; at least 80 cause human disease. Most arboviruses are transmitted by mosquitoes, but some are transmitted by ticks, and one (Oropouche virus) is transmitted by midges. Birds are often reservoirs for arboviruses, which are transmitted by mosquitoes to horses, other domestic animals, and humans. Other reservoirs for arboviruses include arthropods and vertebrates (often rodents, monkeys, and humans). These viruses may spread to humans from nonhuman reservoirs, but human-to-human transmission may also occur by blood transfusion, organ transplantation, sexual contact, and from mother to child during birth depending on the specific virus involved. Human-to-human transmission of most arboviruses through casual, everyday contact has not been documented. Most arboviral diseases are not transmissible by humans, perhaps because the typical viremia is inadequate to infect the arthropod vector; exceptions include dengue Dengue Dengue is a mosquito-borne disease caused by a flavivirus. Dengue fever usually results in abrupt onset of high fever, headache, myalgias, arthralgias, and generalized lymphadenopathy, followed... read more , yellow fever Yellow Fever Yellow fever is a mosquito-borne flavivirus infection endemic in tropical South America and sub-Saharan Africa. Symptoms may include sudden onset of fever, relative bradycardia, headache, and... read more , Zika virus infection Zika Virus (ZV) Infections The Zika virus is a mosquito-borne flavivirus that is antigenically and structurally similar to the viruses that cause dengue, yellow fever, and West Nile virus. Zika virus infection is typically... read more , and chikungunya disease Chikungunya disease Arbovirus (arthropod-borne virus) applies to any virus that is transmitted to humans and/or other vertebrates by certain species of blood-feeding arthropods, chiefly insects (flies and mosquitoes)... read more , which can be transmitted from person to person via mosquitoes. Also, Zika virus Zika Virus (ZV) Infections The Zika virus is a mosquito-borne flavivirus that is antigenically and structurally similar to the viruses that cause dengue, yellow fever, and West Nile virus. Zika virus infection is typically... read more can be transmitted during sexual activity from infected symptomatic or asymptomatic men to their sex partners (male or female) or from infected women to their sex partner.

The Filoviridae consists of 2 genera: Ebolavirus (consisting of 5 species) and Marburgvirus (consisting of 2 species). The specific vectors of these viruses have not been confirmed, but fruit bats are the prime candidates; thus, Filoviridae are not arboviruses. Human-to-human transmission of Ebola virus and Marburg virus Marburg and Ebola Virus Infections Marburg and Ebola are filoviruses that cause hemorrhage, multiple organ failure, and high mortality rates. Diagnosis is with enzyme-linked immunosorbent assay, polymerase chain reaction (PCR)... read more occurs readily.

Laboratory diagnosis often involves viral cultures, polymerase chain reaction, electron microscopy, and antigen and antibody detection methods where available.

Table
icon

Treatment

  • Supportive care

  • Sometimes ribavirin

Treatment for most of these infections is supportive.

In hemorrhagic fevers, bleeding may require phytonadione (vitamin K1 Vitamin K Deficiency Vitamin K deficiency results from extremely inadequate intake, fat malabsorption, or use of coumarin anticoagulants. Deficiency is particularly common among breastfed infants. It impairs clotting... read more ). Transfusion of packed red blood cells or fresh frozen plasma may also be necessary. Aspirin and other NSAIDs (nonsteroidal anti-inflammatory drugs) are contraindicated because of antiplatelet activity. For advanced cases of hantavirus cardiopulmonary syndrome, extracorporeal membrane oxygenation (ECMO) may be needed.

  • Ribavirin 30 mg/kg IV (maximum, 2 g) loading dose followed by 16 mg/kg IV (maximum, 1 g/dose) every 6 hours for 4 days, then 8 mg/kg IV (maximum, 500 mg/dose) every 8 hours for 6 days

Treatment of hemorrhagic fever with renal syndrome Treatment Bunyaviridae contain the genus Hantavirus, which consists of at least 4 serogroups with 9 viruses causing 2 major, sometimes overlapping, clinical syndromes: Hemorrhagic fever with renal syndrome... read more is with IV ribavirin: loading dose 33 mg/kg (maximum, 2.64 g), followed by 16 mg/kg every 6 hours (maximum, 1.28 g every 6 hours) for 4 days, then 8 mg/kg every 8 hours (maximum, 0.64 g every 8 hours) for 3 days.

Antiviral treatment for other syndromes has not been adequately studied. Ribavirin has not been effective in animal models of filovirus and flavivirus infections. The US Food and Drug Administration (FDA) approved 2 drugs to treat Ebola virus disease caused by Zaire Ebola virus in adults and children: a combination of three monoclonal antibodies (atoltivimab/maftivimab/odesivimab) and a single monoclonal antibody (ansuvimab).

Prevention

  • Vector control

  • Prevention of vector bites

  • Sometimes vaccination

  • Avoidance of contact with infected animals, their products, and their excrement (hantaviruses)

The abundance and diversity of arboviruses means that it is often easier and cheaper to control arbovirus infections by destroying their arthropod vectors, preventing bites, and eliminating their breeding habitats than by developing specific vaccines or drug treatments.

Vector control and bite prevention

Diseases transmitted by mosquitoes or ticks can often be prevented by the following:

Diseases transmitted by rodent excreta can be prevented by the following:

  • Before cleaning, ventilate for ≥ 15 minutes closed spaces where mice have been.

  • Wet down surfaces with a 10% bleach solution before sweeping or cleaning.

  • Avoid stirring up dust.

  • Seal sites of potential rodent entry into homes and nearby buildings.

  • Prevent rodent access to food.

  • Eliminate potential nesting sites in and around the home and other buildings.

Guidelines for cleaning up after rodents and working in areas with potential rodent excreta are available from the Centers for Disease Control and Prevention (CDC).

Vaccination

Click here for Patient Education
NOTE: This is the Professional Version. CONSUMERS: Click here for the Consumer Version
Professionals also read
Test your knowledge
Human Papillomavirus (HPV) Virus
Human papillomavirus (HPV) infection is the most common sexually transmitted infection and can cause skin warts, genital warts, or certain cancers. Of the many different strains of HPV, which of the following is most likely to cause visible genital warts?
Download the Manuals App iOS ANDROID
Download the Manuals App iOS ANDROID
Download the Manuals App iOS ANDROID
Download the Manuals App iOS ANDROID
Download the Manuals App iOS ANDROID
Download the Manuals App iOS ANDROID

Also of Interest

Download the Manuals App iOS ANDROID
Download the Manuals App iOS ANDROID
Download the Manuals App iOS ANDROID
TOP