- Equine infectious anemia
Equine infectious anemia virus Virus classification Group: Group VI (ssRNA-RT) Family: Retroviridae Genus: Lentivirus Species: Equine infectious anemia virus
Equine infectious anemia or equine infectious anaemia (EIA), also known by horsemen as swamp fever, is a horse disease caused by a retrovirus and transmitted by bloodsucking insects. The virus is endemic in the Americas, parts of Europe, the Middle and Far East, Russia, and South Africa. The virus is a lentivirus, like human immunodeficiency virus (HIV). Like HIV, EIA can be transmitted through blood, saliva, milk, and body secretions. Transmission is primarily through biting flies, such as the horse-fly and deer-fly. The virus survives up to 4 hours in the carrier. Contaminated surgical equipment and recycled needles and syringes, and bits can transmit the disease. Mares can transmit the disease to their foals via the placenta. The risk of transmitting the disease is greatest when an infected horse is ill, as the blood levels of the virus are then highest.
Acute: The acute form is a sudden onset of the disease at full-force. Symptoms include high fever, anemia (due to the breakdown of red blood cells), weakness, swelling of the lower abdomen and legs, weak pulse, and irregular heartbeat. The horse may die suddenly.
Subacute: A slower, less severe progression of the disease. Symptoms include recurrent fever, weight loss, an enlarged spleen (felt during a rectal examination), anemia, and swelling of the lower chest, abdominal wall, penile sheath, scrotum, and legs.
Chronic: Horse tires easily and is unsuitable for work. May have a recurrent fever and anemia, may relapse to the subacute or acute form even several years after the original attack.
There are currently no statistics available on mortality of EIA. No statistics are available of horses actually dying of acute forms. See also
A horse may also not appear to have any symptoms, yet still tests positive for EIA antibodies. This horse can still pass on the disease. According to most veterinarians, horses diagnosed EIA positive are usually not showing any sign of sickness or disease.
EIA may cause abortion in pregnant mares. This may occur at any time during the pregnancy if there is a relapse when the virus enters the blood. Most infected mares will abort, however some give birth to healthy foals. Foals are not necessarily infected.
Studies indicate that there are breeds with a tolerance to EIA.
Prevention and treatment
A vaccine is available, called "Chinese Live Attenuated EIA vaccine", developed in China and widely used there since 1983. Another attenuated live virus vaccine is in development in the United States.
Reuse of syringes and needles is a risk factor for transfer of the disease. Currently in the United States, all horses that test positive must be reported to federal authorities by the testing laboratory. EIA-positive horses are infected for life.Options for the horse include sending the horse to a recognized research facility, branding the horse and quarantining it at least 200 yards from other horses for the rest of its life, and euthanizing the horse. Very few quarantine facilities exist which usually leads to the option of euthanizing the horse.The Florida Research Institute for Equine Nurturing,Development and Safety aka F.R.I.E.N.D.S. is one of the largest such quarantine facilities and is located in south Florida. The horse industry and the veterinary industry strongly suggest that the risks posed by infected horses, even if they are not showing any clinical signs, are enough of a reason to impose such stringent rules. The precise impacts effect of the disease on the horse industry are unknown.
The Coggins test (agar immunodiffusion) is a sensitive diagnostic test for equine infectious anemia developed by Dr. Leroy Coggins in the 1970s.
Currently, the USA does not have an eradication program due to the low rate of incidence, however many states require a negative Coggins test for interstate travel. In addition, most horse shows and events require a negative Coggins test. Most countries require a negative test result before allowing an imported horse into the country.
It is recommended to verify that all the horses at a breeding farm and or boarding facility have a negative Coggins test before using their services. A Coggins test should be done on an annual basis. Tests every 6 months are recommended if there is increased traveling.
- ^ "Equine Infectious Anemia: Introduction". The Merck Veterinary Manual. 2006. http://www.merckvetmanual.com/mvm/index.jsp?cfile=htm/bc/52800.htm. Retrieved 2007-06-23.
- ^ Equine Infectious Anemia (EIA), North Carolina Department of Agriculture and Consumer Services, retrieved December 19, 2008.
- ^ A Horse, Of Course - Don Blazer at www.donblazer.com
- ^ "Agricultural Biological Diversity", Convention on Biological Diversity, referenced August 12, 2008.
- ^ R.A.M.S. Silva; U.G.P. De Abreu, A.M.R. Dávila, L. Ramirez (1999). "Swamp fever in wild horses from the Pantanal, Brazil" (PDF). Revue d'élevage et de médecine vétérinaire des pays tropicaux 52 (2): 99–101. http://remvt.cirad.fr/cd/EMVT99_2.PDF. Retrieved 2010-10-17.
- ^ Craigo JK, Li F, Steckbeck JD, Durkin S, Howe L, Cook SJ, Issel C, Montelaro RC (2005). "Discerning an effective balance between equine infectious anemia virus attenuation and vaccine efficacy.". J. Virol. 79 (5): 2666–77. doi:10.1128/JVI.79.5.2666-2677.2005. PMC 548432. PMID 15708986. http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=548432.
- ^ http://www.eiahorses.org
Virus: Retroviruses SsRNA-RT virus/
retroviridaeAvian sarcoma leukosis virus · Rous sarcoma virusWalleye epidermal hyperplasia virusOther
DsDNA-RT virus Endogenous
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Look at other dictionaries:
equine infectious anemia — n a serious sometimes fatal disease of horses that is caused by a retrovirus of the genus Lentivirus (species Equine infectious anemia virus) and is marked by intermittent fever, depression, weakness, edema, and anemia called also swamp fever * * … Medical dictionary
equine infectious anemia — n. a viral disease of horses, similar to malaria, characterized by sudden fever, swelling, and anemia; swamp fever … English World dictionary
equine infectious anemia — noun : infectious anemia * * * Pathol., Vet. Pathol. See swamp fever (def. 2) … Useful english dictionary
equine infectious anemia — Pathol., Vet. Pathol. See swamp fever (def. 2). * * * ▪ pathology also called swamp fever disease of horses that is caused by a non oncogenic (non cancer causing) retrovirus. Bloodsucking insects, especially horseflies, transmit the… … Universalium
equine infectious anemia — e′quine infec′tious ane′mia n. vet a viral disease of horses and related animals, characterized by recurring fevers Also called swamp fever … From formal English to slang
equine infectious anemia virus — a virus of the genus Lentivirus that causes equine infectious anemia … Medical dictionary
infectious anemia — n 1) EQUINE INFECTIOUS ANEMIA 2) FELINE INFECTIOUS ANEMIA … Medical dictionary
infectious anemia of horses — Vet. Pathol. See swamp fever (def. 2). Also called equine infectious anemia. * * * … Universalium
infectious anemia of horses — Vet. Pathol. See swamp fever (def. 2). Also called equine infectious anemia … Useful english dictionary
infectious anemia of horses — equine infectious a … Medical dictionary