Vector-borne diseases in horses are illnesses transmitted by vectors such as mosquitoes, ticks, and flies. These diseases can affect equine health by introducing pathogens like viruses, bacteria, or parasites into the horse's system. Common vector-borne diseases in horses include West Nile Virus, Equine Infectious Anemia, and Lyme disease. The transmission dynamics, clinical manifestations, and management strategies for these diseases vary depending on the pathogen and vector involved. Understanding these aspects is important for developing preventive measures and treatment protocols. This page compiles peer-reviewed research studies and scholarly articles that explore the epidemiology, pathogenesis, and management of vector-borne diseases in equines.
Tenbroeck C, Hurst EW, Traub E.Equine encephalomyelitis of the eastern type is a disease of the late summer and fall and cases are found in greatest numbers near salt marshes. The epidemiological findings are against its transmission by contact and favor the view that it is insect borne. Although virus can be demonstrated in the blood of infected horses it is present for a relatively short time, and the possibility that the disease is not primarily an infection of horses but that it is transmitted to them from another host is considered.
The results of integrated human and veterinary surveillance for West Nile virus (WNV) infections in Austria during the transmission seasons 2015 and 2016 are shown. Altogether WNV nucleic acid was detected in 21 humans, horses, wild birds and mosquito pools. In detail: in four human clinical cases [two cases of West Nile fever (WNF) and two cases of West Nile neuroinvasive disease (WNND)]; eight blood donors [among 145,541 tested donations], of which three remained asymptomatic and five subsequently developed mild WNF; two horses with WNND, of which one recovered and one had to be euthanized; ...
Pipitpornsirikul P, Thangthamniyom N, Laikul A, Songkasupa T, Pathomsakulwong W, Apichaimongkonkun T, Kasemsuwan S, E-Kobon T, Lekcharoensuk P.African horse sickness (AHS), a life-threatening disease caused by African horse sickness virus serotype 1 (AHSV-1), emerged in Thailand in February 2020 with 607 cases and a 93% fatality rate. The outbreak was mitigated by vector control and a live attenuated virus (LAV) vaccine. Information regarding viremia and immunity after infection and vaccination during outbreaks are essential for controlling disease transmission. This study evaluated these parameters in 15 infected naïve horses and 11 vaccinated horses during the 2020 outbreak. Whole blood was collected and subjected to RT real-time ...
van Rijn PA, Wernery U, Feddema AJ, Maris-Veldhuis MA, Joseph S, van Gennip RGP.African Horse Sickness (AHS) is a devastating vector-borne viral disease of equids with a mortality up to 95 % in naïve domestic horses. The causative African horse sickness virus (AHSV) is a distinct species of the genus Orbivirus of the family Sedoreoviridae, consisting of nine serotypes showing limited cross protection. AHSV is transmitted by Culicoides biting midges. Outbreaks cause huge economic losses in developing African countries. AHS has become a serious threat for countries outside Africa, since endemic Culicoides species in moderate climates appear competent vectors of the closel...
Silva VVD, Leite DPSBM, Gonçalves LMT, Pinto GOA, Oliveira PRF, Mota RA.Rabies is a lethal zoonosis caused by the rabies virus (RABV), primarily transmitted by the common vampire bat (Desmodus rotundus). Brazil, home to the largest equine population in South America, faces ongoing challenges with equine rabies, which impacts both the economy and public health. This study aimed to identify spatial and temporal patterns of rabies in equines in Brazil between 2006 and 2023. Data from the Zoosanitary Information System (SIZ) of the Brazilian Ministry of Agriculture, Livestock, and Food Supply (MAPA) were used. The incidence risk (IR) was calculated for each region and...
Fonseca-Rodríguez O, Pailler-García L, Urban A, Cáceres G, Napp S, Busquets N.West Nile virus (WNV) is an arthropod-borne virus primarily transmitted by Culex mosquitoes, among birds, but occasionally infecting humans and equids. Understanding environmental factors on the disease occurrence is crucial for planning effective prevention and control strategies. Our study estimates the short-term effects of ambient temperature, relative humidity and precipitation on weekly cases of WNV in equids in Spain, using a space-time stratified case-crossover design. Because WNV transmission occurs sometime after the weather conditions become favorable for the vector, we aimed to est...
Mota RA, Silito IS, Martins MP, Oliveira PRF, Melo RPB, Vieira da Silva V, Jorge FR, Martins TF, Labruna MB.Tick-borne diseases are among the most widespread vector-borne infections, including zoonoses caused by bacterial and protozoal microorganisms. This study consisted of a serosurvey for Rickettsia spp. in 270 horses from 11 farms in the coastal region of Pernambuco, Brazil. Through the indirect immunofluorescence assay (IFA) based on antigens of five Rickettsia species, 164 (60.7%) horses were seroreactive to Rickettsia spp., with seroreactivity among farms ranging from 10 to 100%. Through molecular analysis, all 270 horse blood DNA samples tested negative by PCR assays targeting Anaplasmatacea...
In Italy, West Nile virus (WNV) has been consistently causing disease in humans, horses, and birds since 2008; it was initially confined to the northeast of the country and then spread gradually to the western and southern regions. WNV lineage 1 (WNV-L1) virus was the only lineage that circulated in Italy until 2011, but it was progressively replaced by WNV lineage 2 (WNV-L2). WNV disease in humans was not observed in Sicily, southern Italy, until 2016, when the first case of West Nile neuroinvasive disease (WNND) due to WNV-L1 was reported. Our results demonstrate the introduction of WNV-L2 i...
Djellouli M, Eddaikra N, Beneldjouzi A, Benikhlef R, Ghimire R, Wilkins M, Lafri I.Cutaneous leishmaniosis remains a major public health concern in Algeria, predominantly affecting humans and dogs. However, the role of other animal hosts, particularly equids, in the transmission cycle remains underexplored. This cross-sectional study presents the first systematic investigation of Leishmania spp. exposure and infection in equids, along with associated environmental and host factors, from southeastern Algeria, El Oued Wilaya, the third most affected region for human cutaneous leishmaniasis in the country. A total of 122 equids from eight communes were clinically examined and t...
Gholmohammadi S, Malekifard F, Yakhchali M.Ticks are important ectoparasites in equids, causing economic losses in animal husbandry in Iran and worldwide. This study was aimed to determine frequency and species diversity of hard ticks in equids in Ardabil province, during the four seasons in 2021. A total of 240 equids (187 horses, 53 donkeys) were randomly selected and examined. Ixodid ticks were collected from body surface of examined animals and identified. Of all examined equids, 32.5% horses, and 4.58% donkeys were infested with a total number of 412 ixodid ticks. Tick indices (tick number per animal) were 4.62. There was signific...
Silva-Ramos CR, Niño Rodríguez JA, Gil-Mora J, Betancourt-Ruiz P, Martínez-Díaz HC, Forero-Becerra E, Matiz-González JM, Bolaños E, Olaya-M LA....Babesia species are tick-borne protozoan parasites which affect several animal species. Babesia spp. infections are significantly important for veterinary medicine, affecting a wide range of domestic animal species such as dogs, cattle, and horses. In Colombia, studies of Babesia spp. infections in domestic animals are scarce. Thus, the aim of the present study was to explore the circulation of these parasites among domestic canines, bovines and equines from the department of Cauca. Methods: Between August and November, 2017, active domestic animal sampling of cattle was performed in eight rur...
Montini M, Torrents J, Nava S, Sebastian PS. ticks collected on horses from the North-West of Argentina were analyzed for the presence of the Piroplasm agents and . A total of 97 adult ticks from four different provinces (Jujuy, Santiago del Estero, Salta, Tucumán) were included in this study. Genomic DNA was isolated, and conventional PCR assays were applied for the detection of the 18S rDNA gene of and species. One sample corresponding to a male of collected in Tapia, Tucumán Province, resulted positive. Phylogenetic analyses carried out with the obtained 18S rDNA partial gene sequences resulted in the identification of . Althou...
Al-Rammahi HM, Mohsen RK, Othman RM.West Nile virus (WNV) circulates between birds and mosquitoes, with horses and humans as incidental dead-end hosts. Despite documented cases in neighboring countries and human cases in southern Iraq, no previous studies have investigated WNV in Iraqi horses. Unassigned: To determine the seroprevalence of WNV in horses from three southern Iraqi governorates (Thi-Qar, Misan, and Basrah) between March and June 2024. Unassigned: Blood samples were collected from 236 horses regardless of age, sex, or health status. Serum samples were analyzed using commercial competitive enzyme-linked immunosorbent...
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...
Faghihzadeh Gorji F, Sadr S, Eshrati H, Borji H.Worldwide, equines are affected by equine filariosis, an endemic vector-borne disease caused by heterogenous parasitic nematodes. The main objective of this study was to determine the prevalence of filarial infection among horses in the North and Northeast of Iran. Between October 2021 and July 2022, 145 equine blood samples were investigated, of which 49 cases were from the northeast and 96 were from the north of Iran. Blood samples were taken for microfilariae using Knott's method. Out of 145 blood samples, only 2 cases (1.37%) from northern Iran were positive for microfilaria of , and no po...
Christofi E, Hoopes J, El-Hage C, Coffin J, Riley T, Cumming B.Since their arrival in the 1700s, horses have played a significant role in shaping the identity of rural and remote communities. However, Indigenous perspectives on the historical role of horses in communities have been largely underrepresented. In remote regions, where access to veterinary and medical services is limited, interactions between people and free-roaming horses present a potential risk for zoonotic disease transmission. This review identifies potential pathways for the transmission of equine zoonoses in rural and remote Aboriginal and Torres Strait Islander communities, aiming to ...
Pineda V, Calzada JE, Montilla S, Rodríguez I, Howard E, Torres AI, Vasquez V, Reina A, Saldaña A, González K. (CL) is a vector-borne zoonotic disease affecting the skin and mucous membranes of animals and humans. While CL is commonly diagnosed and studied in humans in Panama, limited information exists on its occurrence in domestic animals and their potential role as reservoirs. In this study, samples from twelve domestic animals (ten dogs and two horses) with suspected CL lesions were collected between 2021 and 2025 in endemic regions of Panama and evaluated using multiple diagnostic methods. infection was confirmed in six of them (50%): five dogs and one horse. Three dogs were infected with () , ...
Wei W, Lan Z, Li C, Liu X, Zhang X, Wang J, Bai X, Zhou L, Wang X, Wang C, Gao J.Babesia species are tick-transmitted hemoprotozoa that infect mammals, birds, and humans, posing a significant global threat to veterinary medicine threat. In this study, the authors systematically retrieved articles on the occurrence of Babesia species in domestic herbivores in China, including ovine, bovine, and equine species, through a search in the following six databases from their inception to 4 November 2024: PubMed, Web of Science, ScienceDirect, Chinese National Knowledge Infrastructure, Wanfang Data, and VIP Chinese Journal Database. A total of 94 studies (54 high-quality studies, 4...
West Nile virus (WNV) circulates endemically in Romania, yet prevention of WNV infection in horses largely depends on owner-driven decisions that require accurate risk perception and veterinary guidance. A cross-sectional online survey was carried out between May and November 2025 to evaluate the knowledge, attitudes, and preventive practices (KAP) regarding WNV among 227 horse owners from various Romanian regions. In total, 67.4% of respondents had previously heard of WNV. The main transmission route was correctly identified as mosquito bites by 49.8% of participants, while 32.2% answered "do...
Liang S, Xu Z, Liu X, Yang Y, Zhao L, Hu C, Hou J, Wei Z, Zhang Y, Li D, Yang J, Zhang J, Bi J, Wang Y, Lou Z.Western equine encephalitis virus (WEEV), a group of encephalitic alphaviruses that cause severe diseases in humans and equids, historically used the very-low-density lipoprotein receptor (VLDLR) as a receptor during infection. However, current epidemic strains no longer use VLDLR as a receptor. In this study, we identify that LA1, LA2, LA3, and LA5 of VLDLR can directly interact with WEEV. Using cryo-electron microscopy, we investigate the structures of complexes formed between WEEV and VLDLR-LBD or other VLDLR fragments. Our findings show that LA1 and LA2 insert into a cleft formed by two ad...
Ehizibolo DO, Oyekan O, Mkpuma N, Haliru H, Garba I, Turaki IZ, Williams EE, Danmarwa A, Mohammed A, Muhammad MA, Abubakar M, Brown C, Faburay B.Rift Valley Fever (RVF) is a neglected vector-borne zoonotic disease of significant veterinary and public health concern in Sub-Saharan Africa. This study investigated the seroprevalence of Rift Valley Fever Virus (RVFV) exposure and associated risk factors among camels and horses marketed in northern Nigeria. A total of 1117 animals were sampled, comprising camels (812) and horses (305), across three major livestock markets (Maigatari, Maiduguri, and Illela). The overall seroprevalence was 18.8% (95% CI: 16.6-21.2%), with a striking six-fold disparity: camels showed a prevalence of 24.4% (95%...
Stokes JE, Labuschagne K, Fèvre EM, Baylis M.In recent decades there has been a huge increase in the export of cut flowers from countries in Africa and elsewhere to European flower markets, with the vast majority first entering the Netherlands for local use or for export. Coincidentally, three significant livestock disease outbreaks caused by viruses associated with Africa or other tropical regions were first detected in the Netherlands (bluetongue virus serotype 8 (BTV-8), 2006, and BTV-3, 2023) and in western Germany about 200 km from the Netherlands border (Schmallenberg virus, SBV, 2011). This study aimed to determine whether Culic...
Ma W, Gao L, Wu X, Zhong L, Huang X, Yang R, Wu H, Zhu L, Ma W, Peng L, Li B, Song J, Luo S, Bao F, Liu A.Both Borrelia burgdorferi (Bb) and Anaplasma phagocytophilum (Ap) can infect humans and animals through tick-borne transmission, resulting in zoonosis. Under certain conditions, human infection can lead to Lyme disease (LD) and human granulocytosis (HGA), whereas infection in animals can cause various acute and non-specific symptoms. The combination of Bb and Ap has been reported to increase the disease severity in infected animals. In this systematic review and meta-analysis, we investigated the global diversity of Bb and Ap coinfection in animals and their prevalence and distribution regardi...
Bland J, McGowan C, Bush E, Lloyd V.Zoonotic diseases have major impacts on human and animal health, as well as being ecologically significant. Lyme Borreliosis or Lyme disease, caused by infection by pathogenic members of the Borrelia genus, is among these zoonotic diseases. Serology is one of the most accessible means for indirect surveillance of pathogen presence by monitoring the presence, abundance, and type of immune response to the pathogen or pathogen-associated epitopes. Serological surveillance of wild animals is important as wild animals are the primary reservoirs of many zoonotic diseases. Similarly, serological sur...
Kumar B, Brahmbhatt NN, Thakre B, Maharana BR, Parmar VL, Kumar M.Haemoparasitic diseases constitute a significant constraint to economic livestock farming. Diagnostic techniques that are inexpensive, rapid, reliable, and precise are crucial for the management of diseases. In this context, PCR assays are very valuable yet expensive since the samples must be processed before being included in the PCR reaction. Accordingly, the goal of the current study was to lower the PCR costs without jeopardizing the assay's sensitivity and specificity. For that purpose, the alkaline solution was optimized for low cost and quick DNA extraction (blood lysate), and PCR reage...
Rosa-Xavier IG, Pinter A, Giuffrida R, Biondo AW, Kmetiuk LB, Santarém VA.(1) Background: Brazilian spotted fever (BSF) is a tick-borne disease that has occurred in several Brazilian regions, caused by spp. bacteria and mainly transmitted by ticks. Despite the high BSF lethality in several Brazilian endemic areas, predictors and associated risk factors remain to be fully established. Accordingly, the retrospective study herein aimed to assess BSF cases and associated factors in an endemic area of western São Paulo state. (2) Methods: Notified cases identified by the System for Epidemiological Surveillance of São Paulo (CVE), from January 2007 to December 2021, w...
Gomes-Gonçalves S, Mesquita JR, Ruano ZM, Barradas PF.Coxiella burnetii is a bacterium that causes coxiellosis in animals and Q fever in humans. While ruminants are the main reservoirs, the role of ticks in their transmission is still uncertain. This study looked for C. burnetii in ticks collected from two autochthonous breeds in Portugal: Churra Galega Mirandesa sheep and Garrano horses. A total of 555 ticks were tested, including 100 Rhipicephalus sanguineus sensu (s.) stricto (s.) from sheep and 455 Rhipicephalus bursa from horses. Coxiella burnetii was found in 7 % of R. sanguineus s.s., but not in R. bursa. Phylogenetic analysis confirmed th...
Ma X, Zhang M, Zhang X, Qi T, Zhang W, Zhao Y, Na L, Zhang Y, Wang XF, Wang X.African horse sickness (AHS) is a lethal vector-borne disease caused by African horse sickness virus (AHSV) and represents a major threat to equine health and the horse industry. In 2020, outbreaks of AHS caused by AHSV serotype 1 (AHSV-1) were reported in Thailand, increasing the risk of AHS introduction into China. Given the safety issues associated with currently available live attenuated AHS vaccines, the development of safer and more effective vaccination strategies is urgently needed. In this study, we constructed a recombinant fowlpox virus (rFPV) expressing the AHSV-1 VP2 protein as a ...
Buyens ARM, van Staden V, Theron J.African horse sickness, caused by African horse sickness virus (AHSV) that is transmitted by midges of the Culicoides genus, leads to rapid mortality among horses. Proteases in the saliva of Culicoides midges cleave the VP2 outer capsid protein, resulting in infectious sub-virus particles that have increased infectivity for the Culicoides vector insect and Culicoides-derived cells (KC cells). The AHSV VP7 protein has an arginine-glycine-aspartate (RGD) motif, but the functional relevance of this protein and motif in facilitating binding to insect cells is unknown. To investigate, core-like par...
Langlands Z, Gubbins S, Carpenter S, England M.African horse sickness virus (AHSV: Sedoreoviridae; Orbivirus) causes a severe and often fatal disease in horses (African horse sickness: AHS) and is transmitted almost exclusively by Culicoides biting midges (Diptera: Ceratopogonidae). In recent years, unprecedented outbreaks of AHSV have occurred in new geographical foci in Thailand and other related Culicoides-borne viruses continue to emerge unexpectedly, causing disease outbreaks in northern Europe. This study investigated Culicoides abundance and diversity at a donkey (Equus asinus) sanctuary in southern England. The incidence and severi...
Rymaszewska A, Kubiak K, Dmitryjuk M, Rząd I, Kirczuk L.Ixodes ricinus is a widespread vector of numerous microorganisms pathogenic to humans and animals in Europe. The risk of exposure to tick-borne pathogens (TBPs) has increased in recent years due to climate change, the conversion of natural green areas to recreational areas, and growing human and animal populations, including pets. Using molecular methods, the prevalence, diversity, and co-occurrence of selected tick-borne microorganisms were assessed in questing I. ricinus collected from recreational areas (n = 409), in ticks feeding on horses (n = 135), and in blood samples from red d...