Equine Infectious Anemia Virus (EIAV)

Equine Infectious Anemia Virus (EIAV)

EIAV is a retrovirus causing Equine Infectious Anaemia (EIA) — a lifelong infection with no cure, characterized by intermittent fever, anaemia, weight loss, and potential death. Many horses become asymptomatic carriers, posing a hidden risk for transmission.

EIAV is notifiable in many countries and is primarily transmitted by:

• Blood-feeding insects(e.g. horseflies)
• Iatrogenic routes(e.g. contaminated needles or instruments)
• In utero or via colostrum/milk in rare cases

Clinical phases may include:

• Acute phase – high fever, lethargy, thrombocytopenia
• Chronic phase – recurrent illness, weight loss, oedema
• Carrier state – outwardly healthy but infectious

qPCR testing enables:

• Direct detection of EIAV proviral DNA or RNA from whole blood (EDTA)
• Identification of infected carriers, particularly valuable where serology may be inconclusive
• Rapid confirmation in suspect cases or pre-export and pre-breeding testing

qPCR complements or confirms results from the Coggins test (AGID) and is increasingly used in outbreak investigations and international movement protocols.

Accurate and early detection is essential for preventing disease spread, enforcing quarantine, and protecting the health of equine populations.