Table 1.

Viruses identified in horses

Virus	Family	Size (nm)	Genome	Reported presence in horse blood	Classified as pathogenic to humansa
Enveloped
Arteritis virus	Arteriviridae	50–60	ss-RNA	NR	–
Borna virus	Bornaviridae	70–130	ss-RNA	Yes	Yes
Eastern & western equine encephalitis virus	Togaviviridae	40–70	ss-RNA	NR	Yes
Equine coronavirus	Coronaviridae	75–160	ss-RNA	NR	–
Equine foamy virus	Retroviridae	80–100	ss-RNA	Yes	–
Equine herpes virus1-5	Herpesviridae	125–150	ds-DNA	NR	Yes
Equine infectious anaemia virus	Lentiviridae	80–100	ss-RNA	Yes	–
Equine influenza virus	Orthomyxoviridae	80–120	ss-RNA	NR	Yes
Equine morbilli virus (Hendra virus)	Paramyxoviridae	150	ss-RNA	NR	Yes
Japanese encephalitis virus	Flaviviridae	40–70	ss-RNA	NR	Yes
Nipah virus	Paramyxoviridae	150	ss-RNA	NR	Yes
Salem virus	Paramyxoviridae	150	ss-RNA	NR	–
St-Louis encephalitis virus	Flaviviridae	40–70	ss-RNA	NR	Yes
Venezuelan equine encephalitis virus	Togaviridae	40–70	ss-RNA	Yes	Yes
Vesicular stomatitis virus	Rhabdoviridae	50–380	ss-RNA	Yes	Yes
West Nile virus	Flaviviridae	40–70	ss-RNA	Yes	Yes
Non-enveloped
Equine encephalosis	Reoviridae	80	ds-RNA	NR	–
Equine rhinitis A and B viruses	Picornaviridae	22–30	ss-RNA	NR	–
Equine rotavirus	Reoviridae	60–80	ds-RNA	NR	–

NR = not reported based on literature search but cannot be excluded.

^aBased on the recent EMEA note for guidance [19].