Arbovirus

Definition

Any virus that is transmitted to vertebrate hosts by hematophagous arthropod vectors, primarily mosquitoes, ticks, sand flies, and biting midges. The term is epidemiological rather than taxonomic, encompassing diverse RNA virus families (notably Togaviridae, Flaviviridae, Bunyavirales, and Reoviridae) united by their transmission ecology. Arboviruses replicate in both the arthropod vector and the vertebrate host, maintaining cycles that may be zoonotic (animal-to-animal with incidental human involvement) or urban (human-mosquito-human).

Etymology

Portmanteau of arthropod-borne virus, coined in the 1950s to classify viruses by transmission mode rather than virological taxonomy.

Example

Yellow fever virus (Flaviviridae) is a mosquito-borne arbovirus maintained in sylvatic cycles involving canopy-dwelling mosquitoes and nonhuman primates, with Aedes aegypti driving urban epidemics when humans enter the transmission cycle.

Synonyms

• arthropod-borne virus

Related Terms

• vector-borne disease
• Hematophagy
• viral zoonosis
• Tibovirus
• sylvatic cycle
• urban cycle
• flavivirus
• alphavirus

Usage Notes

Not a formal taxonomic rank; viruses in different families may share arbovirus status. Specialists increasingly prefer 'arthropod-borne virus' in formal writing to avoid the informal '-virus' suffix. Tibovirus (tick-borne virus) is occasionally used for tick-specific transmission but remains rare. Many arboviruses exhibit biological transmission (replication in vector) versus mechanical transmission (passive transfer); this distinction matters for vector competence studies. Geographic expansion of arboviruses (e.g., Zika, West Nile, chikungunya) tracks vector range shifts driven by climate and land-use change.