Equine Infectious Anemia (EIA) is a viral disease affecting horses, caused by the Equine Infectious Anemia Virus (EIAV), a member of the Lentivirus genus. The disease is characterized by intermittent fever, anemia, edema, and weight loss, though some horses may remain asymptomatic carriers. Transmission occurs primarily through blood-feeding insects such as horseflies and deerflies, or through contaminated instruments. EIA is diagnosed using serological tests, with the Coggins test being a commonly used method for detection. There is no vaccine or cure for EIA, and management primarily focuses on prevention and control measures to limit transmission. This page assembles peer-reviewed studies and scholarly articles that explore the pathogenesis, epidemiology, diagnostic methods, and management strategies related to Equine Infectious Anemia.
Cardeti G, Manna G, Cersini A, Nardini R, Rosati S, Reina R, Cittadini M, Sittinieri S, Altigeri A, Marcario GA, Scicluna MT.The mechanisms of the innate immunity control of equine infectious anemia virus in horses are not yet widely described. Equine monocytes isolated from the peripheral blood of three Equine infectious anemia (EIA) seronegative horses were differentiated in vitro into macrophages that gave rise to mixed cell populations morphologically referable to M1 and M2 phenotypes. The addition of two equine recombinant cytokines and two EIA virus reference strains, Miami and Wyoming, induced a more specific cell differentiation, and as for other species, IFNγ and IL4 stimulation polarized horse macrophages...
Peris MP, Serrano M, Romero A, García M, Halaihel N, Castillo JA, Gracia MJ.Equine piroplasmosis (EP), a tick-borne disease caused by Babesia caballi and Theileria equi, is of significant concern due to its impact on the international horse trade. According to standards established by the World Organisation for Animal Health (WOAH), horses imported from EP-endemic regions must have a certificate confirming negative serological and molecular test results. In EP-free countries, only seronegative horses are allowed to enter. This entails economic losses for endemic regions such as Spain. Our study aimed to assess the prevalence of B. caballi and T. equi in horses from no...
James K, Chappell DE, Craig B, Pariseau C, Wright C, van Harreveld P, Barnum S, Pusterla N.The purpose of this study was to determine any associations of EHV-2, EHV-5, and dual infection with EHV-2/-5 with demographic parameters, clinical signs, and coinfection with other common respiratory pathogens. Nasal swabs collected from 9737 horses were tested for EHV-2 and EHV-5, as well as EHV-1, EHV-4, EIV, , ERAV, and ERBV, by qPCR. Clinical signs and demographic parameters were recorded, and prevalence factors were evaluated for significance regarding EHV-2 and/or EHV-5 infection. Out of the 9737 horses in this study, 17.8% tested EHV-2-positive ( = 1731), 15.8% tested EHV-5-positive ( ...
Andreas C.The virus that causes African horsesickness does not affect any indigenous species, but produces high mortality among horses, a species introduced by the Dutch East India Company in 1653. While the insect-borne disease did not occur in the immediate vicinity of the Cape Peninsula, horsesickness could have constituted an endemic disease barrier to the horse-based expansion of the colonial sphere into the hinterland, where it was seasonally prevalent. That it did so to only a limited extent is due to a substantial alteration of the ecology of the disease that largely resulted from inadvertent si...
Acevedo-Jiménez GE, Morales-González C, Akbarin MM, Rodríguez-Murillo C, González-Fernández VD, Avila-De la Vega LM, García-Flores MM....Equine infectious anemia virus (EIAV) is a globally significant equine pathogen, and its control relies on effective serological surveillance. The agar gel immunodiffusion (AGID) test, the WOAH-prescribed method, has limitations in sensitivity. This study developed and validated an indirect ELISA using a synthetic peptide derived from a conserved region of the EIAV gp90 surface glycoprotein. The assay was evaluated using 773 horse sera from the Metropolitan Zone of the Valley of Mexico and compared to the AGID test. The gp90-EIAV ELISA demonstrated a sensitivity of 85.3 % and a specificity o...
Gordon S, Pusterla N, Finno CJ, Young A, Martínez-López B.Equine alphaherpesvirus-1 (EHV-1) is a highly contagious virus that can cause the neurological form, equine herpesvirus myeloencephalopathy (EHM). Understanding transmission-related risk factors is crucial for improving prevention strategies and guiding effective control measures. In this study, we collected data from 63 horses that had previously participated in the February 2022 winter horse show season at the Desert International Horse Park (DIHP) (26 cases and 37 controls) to identify host and management factors associated with EHV-1 infection and/or EHM development during the February 202...
Equestrian sports play a significant economic role in the horse industry. In recent years, numerous equine viruses have emerged, among which are equine Pegiviruses and the re-emerging Equine coronavirus (ECoV). These viruses are distributed globally and primarily cause subclinical infections with unknown morbidity, even if ECoV can occasionally induce febrile and diarrheic episodes. To broaden the data on the Italian equine population, a study was conducted to assess their prevalence in two distinct horse populations belonging to the Carabinieri Corps (CC) and the Italian Army (IA) of the Ital...
Costa VMD, de Aguiar Filho RN, Braz GF, Paz CFR, Drumond BP, Teixeira BM, Kroon EG.Equine infectious anemia (EIA) is a chronic disease caused by the equine infectious anemia virus (EIAV), a member of the Retroviridae family and the Lentivirus genus. Most infected animals are asymptomatic carriers, which makes clinical diagnosis challenging. This study aimed to conduct a clinical and laboratory evaluation of EIA in equids used for equestrian tourism in Jericoacoara National Park, Ceará, Brazil. A total of 112 equids (104 horses and 8 mules) underwent clinical, hematological, biochemical, serological, and molecular assessments. The EIAV seropositivity rates were 11.6% by AGID...
In 2017, Spain reported its first equine infectious anemia virus (EIAV) outbreak in 34 years, affecting three horses in two unrelated holdings in Candeleda (Ávila) and Serradilla (Cáceres), with no apparent epidemiological link between premises. Phylogenetic analysis of whole genome and the gene revealed that the Spanish EIAV strains form a distinct monophyletic clade, sharing more than 99% nucleotide identity, suggesting a common contamination event. Interestingly, these three viral strains seem to cluster with North American strains, sharing up to 80.12% nucleotide identity, notably with ...
Gonzálvez M, Franco JJ, Cano-Terriza D, Barbero-Moyano J, Jose-Cunilleras E, García J, Alguacil E, García-Bocanegra I.Equine Infectious Anemia (EIA) is a notifiable disease caused by Equine Infectious Anemia Virus (EIAV), with major sanitary and economic importance for equids worldwide. There is limited and outdated information on the circulation of EIAV in many European countries. In the present study, we aimed to assess virus exposure in different equid species in Western Europe. Methods: Between 2011 and 2023, a cross-sectional study was conducted to investigate the seroprevalence of EIAV in 1676 equids (1444 horses, 106 donkeys and 126 mules/hinnies) from four European regions: Andalusia (Southern Spain; ...
Garzaro D, Rodríguez N, Medina G, Alcazar W, Gualdron M, Siem JA, Sulbaran Y, Barrios M, Liprandi F, Jaspe RC, Pujol FH.Madariaga virus (MADV), formerly known as the South American variant of Eastern Equine Encephalitis virus (EEEV), is an alphavirus that belongs to the family and has been periodically infecting equids in Venezuela since its first identification in 1975. This study reports the isolation and molecular characterization of MADV isolated from a horse in December 2024 in the context of MADV cases reported in Venezuela. Methods: Antibodies to the rabies virus were detected by indirect immunofluorescence, and to the Equine Infectious Anemia virus (EIAV) by passive immunodiffusion. MADV RNA was detect...
Equine infectious anemia virus (EIAV) is an equine lentivirus related to human immunodeficiency virus type 1 (HIV-1). Both viruses are related among the Retroviridae family, but their clinical manifestations are different as EIAV causes a long persistent infection with no progressive immune dysfunction in most cases. Today, no treatment is approved against EIAV, contrary to HIV-1, manageable through antiretroviral therapy, known as HAART (highly active antiretroviral therapy) or cART (combination antiretroviral therapy). No information about the efficacy of antiretroviral drugs against EIAV is...
Pinho APVB, Ferreira F, Fuck JJ, de Oliveira JP, Dias RA, Grisi-Filho JHH, Heinemann MB, Telles EO, Amaku M, Ferreira Neto JS.Considering that control strategies for Equine Infectious Anemia, based on the serological diagnosis of equids and the removal of positive animals, may not be optimal for developing countries with an absolute predominance of grade working animals, this study aimed to address this issue based on the epidemiological situation of the disease in Pará, a state in the Brazilian Amazon. Pará was divided into five regions, and within each region a pre-established number of farms were randomly selected. Within each farm, a pre-set number of animals were randomly selected and submitted to Agar Gel Imm...
Domínguez-Odio A, González LIC, Alfonso DM, Guevara-Hernández F, La O Arias MA, Zayas MP, Ríos MÁB.The transmembrane glycoprotein gp45 (implicated in virus-equine B lymphocyte binding and in subsequent infection) is an important protein used as an antigen in the serological diagnosis of equine infectious anemia, but synthetic peptides derived from its structure are not. Consequently, the present study aimed to determine the diagnostic performance of the Bio-AIELAB immunoassay (novel synthetic peptide P05/gp45) in comparison with a similar commercial assay (ELISA EIA, VMRD Inc, USA) and with the gold standard (AGID, LABIOFAM, Cuba). A total of 365 samples of sera from naturally infected Cuba...
da Silva VV, de Sá Barreto Maia Leite DP, de Crasto Souza Carvalho Reis J, de Almeida Braz BM, Junior JWP, de Almeida JC, Mota RA.This study identifies high-risk areas for Equine Infectious Anemia (EIA) in Brazil and analyzes the temporal trend of the disease across regions and Federative Units over an 18-year period (2006-2023), using data from the National Animal Health Information System (SIZ). During the analyzed period, 111,826 cases of EIA were reported in Brazil, with a predominance in the Northeast (39.75 %), Central-West (27.56 %), and North (20.95 %) regions. The state of Mato Grosso recorded the highest number of cases (17.02 %), while Sergipe had the lowest (0.36 %). In the incidence risk analysis, the s...
