Equine Viral Arteritis Essay

Horse Virus Detection and Treatment

Equine viral arteritis (EVA) is defined by Timoney (2019) in the Merck Veterinary Manual as “an acute, contagious, viral disease of equids caused by equine arteritis virus (EAV).” EAV is also known as Epizootic cellulitis-pinkeye, Equine typhoid, and Rotlaufseuche (Timoney, 2019). The virus can cause symptoms of fever, conjunctivitis, depression, anorexia, nasal discharge, skin rash, subfertility in stallions, and death on young foals and abortion in mares (Price, Rentsch, Burn & Spector, 1998). 

The etiology of EVA starts with respiratory exposure: the virus invades the respiratory tract, where it then proceeds to duplicate itself in the tonsillar tissue and nasopharyngeal epithelium, as well as in bronchial macrophages (Timoney, 2019). Cells infected by EVA then transmit the virus to the lymph nodes, resulting in further multiplication of the virus and ultimate release into the carrier’s blood stream. Within one week, EVA will localize in small blood vessels and panvasculitis will result. The adrenals, thyroid and liver will also be infected. Vascular lesions, swelling and necrosis of infected vessels will occur, which sets off a chain reaction of negative effects, including edema and hemorrhaging. After a week and half, lesions will go into repair. After a month of infection, the virus is typically no longer detectable, though carrier stallions will carry the virus in their sex glands for years (Timoney, 2019). Currently no evidence exists that the disease can be contracted by humans, and it is hypothesized that it may also infect alpacas and llamas. Transmission between equines occurs via respiration, venereal contact or congenitally (Timoney, 2019). It is not a Foreign Animal Disease but does occur globally among equines throughout the world. EVA is a reportable disease in Virginia (Virginia Department of Health, 2016).

Clinical signs include fever, dependent edema on the hind limbs and mid-ventral edema on stallion’s scrotum and sheath (on mammary glands in the mare). Conjunctivitis may also be seen. Nasal discharge, lacrimination, hives, and depression have been found but these signs are rare (Timoney, Creekmore, Meade, Fly, Rogers and King, 2008). History questions that would be important to ask would be whether the horse has moved locations recently or come into contact with other horses, whether semen shipments were received and used, and what donors or recipients were recently at the farm (Timoney et al., 2008).

The disease is diagnosed by lab testing (Timoney et al., 2008). The…