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.
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...
West Nile virus (WNV) is a mosquito-borne flavivirus that remains an important public and veterinary health concern across Europe. Periodic outbreaks affecting humans, horses, and wildlife highlight the complex ecological interactions underlying viral circulation. This narrative review aims to synthesize current knowledge regarding WNV epidemiology, transmission dynamics, and surveillance strategies in Europe, with particular attention to the Romanian context. Available surveillance data indicate recurrent seasonal transmission in several European regions; however, reported case numbers may be...
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...
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%...
Paulussen E, Delhaas T, Decloedt A, van Loon G, Van Steenkiste G.Twelve-lead electrocardiography (ECG) is essential in human cardiology but remains poorly investigated in equine medicine due to a lack of standardization and inconsistent findings. Objective: Describe the normal vectorcardiogram (VCG) variation in horses at rest and during exercise using Delta 12-lead ECG, including repeatability and intra- and interobserver variations. Methods: One hundred two healthy Warmblood horses, aged 3-20 years, were examined at rest, of which 30 also during exercise. Methods: Prospective, observational study. Electrocardiograms were recorded using a Δ 12-lead confi...
Dao TTH, Szűts T, Duong NN, Troung DTQ, Solymosi N, Takács N, Hornok S, Farkas R.Equine piroplasmosis, caused by , and , significantly impacts on the veterinary and economic aspects of the global horse industry. However, many countries, including Vietnam, have not yet conducted epidemiological surveys to determine the prevalence of these haemoparasites. This study aimed to detect and/or infections in horses and to identify their genotypes. Blood samples were collected from 154 apparently healthy horses in eight districts of Hanoi, Thai Nguyen, and Son La provinces located in the northern part of the country. Twenty-four horses (15.58%, 95%CI: 10.70–22.14%) were found ...
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...
Schliewert EC, Hooijberg EH, Goddard A.African horse sickness (AHS), caused by the vector-borne African horse sickness virus (AHSV), is endemic to sub-Saharan Africa and infection results in high mortality in naïve equine populations. Clinical signs include submucosal petechiae and prolonged bleeding post venepuncture indicative of hypocoagulation. Pathological activation of haemostasis may result from tissue factor expression as a result of vascular endothelial damage or dysfunction, the proposed pathologic mechanism in AHS, potentially resulting in disseminated intravascular coagulation (DIC). Objective: To describe haemostatic ...
Dorrego A, Olvera-Maneu S, Jose-Cunilleras E, Gago P, Raez A, Rivera B, Oporto A, Gonzalez S, Cruz-Lopez F.The forest fly ) is an obligate haematophagous dipteran insect (order Diptera) that primarily infests horses and may contribute to the circulation of vector-borne pathogens. This study aimed to investigate the presence of , s.l., , and , important vector-borne pathogens of equids, in forest flies collected from horses in endemic areas of Spain. A total of 170 forest flies were collected from 39 equids across four geographical regions in Spain (Segovia, Madrid, Toledo, and Menorca) and blood samples were collected from 27 of these horses. All flies were morphologically and molecularly identifi...
Murillo A, Lebrero ME, Valdés M, Ramos J, Villanueva-Saz S, Davies JE, Gómez Á, Pérez E, Riera C, Marteles-Aragüés D.Equine leishmaniosis, caused by Leishmania infantum and transmitted by infected sand flies, has been increasingly reported in Europe, although clinical and immunological data remain scarce. We describe a 10-year-old mare from southern Spain presenting with periocular nodular lesions. Histopathology and immunohistochemistry confirmed granulomatous dermatitis with intrahistiocytic Leishmania amastigotes. Additionally, Leishmania infantum DNA was detected in paraffin embedded skin biopsy. Following surgical removal of the lesions, sequential serological monitoring using enzyme-linked immunosorben...
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 ...
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...
Posada-Guzmán MF, Jiménez-Rocha AE, Sánchez-Bermúdez JF, Romero-Zúñiga JJ, Dolz G.Equine piroplasmosis, caused by Babesia caballi and Theileria equi, is endemic in Costa Rica. However, the presence of these hemoparasites in tick vectors has not been documented in the country. Objective: To identify tick species infesting horses in four Indigenous communities and to determine the presence of B. caballi and T. equi DNA in ticks from piroplasmosis-positive horses. Methods: Ticks (n = 1063) were collected from 129 horses in four Indigenous communities. Species identification and sex classification were performed. From 76 PCR-positive horses, 203 ticks were analyzed for B. cabal...
Morales J, Ruano MJ, Tena-Tomás C, van Schalkwyk A, Loundras EA, Valero-Lorenzo M, López-Herranz A, Romito M, Batten C, Villalba R, Agüero M.African horse sickness (AHS) is a disease affecting equids caused by the AHS virus (AHSV). The World Organisation for Animal Health (WOAH) includes AHS as a notifiable disease and, upon detection within the European Union, immediate control and eradication measures are mandated. Thus, validated diagnostic methods for rapid AHSV detection are essential. The Agüero 2008 and Guthrie 2013 rRT-PCR methods have been widely validated for detection of any AHSV strain and are included as reference rRT-PCRs in the WOAH manual. However, the WOAH Reference Laboratory for AHS in the Republic of South Afri...
West Nile Virus (WNV) is a mosquito-borne zoonosis with recurrent equine and human cases in Romania. Horses, although dead-end hosts, act as sentinels for local viral circulation. Farm-level risk conditions remain under-characterized. This pilot, exploratory cross-sectional study assessed 42 equine facilities in western Romania (2024). A standardized 10-item checklist was applied and a Composite Environmental Risk Score (CERS) (0-10, unweighted) was computed per facility. Spatial analysis in QGIS included distances to nearby water bodies. No serological or entomological data were collected; th...
Piketh G, Viljoen A, Eberhardt C.Equine encephalosis (EE) is caused by an Orbivirus from the family Sedoreoviridae and is thus similar to African horse sickness (AHS) and Bluetongue viruses (BTV). These viruses are transmitted by Culicoides midges. Equine encephalosis can infect horses, donkeys and zebras sub-clinically while only horses develop clinical disease. The vector's distribution is climate-dependent with evidence for circulation in Southern Africa, the Middle East and India. Global warming could facilitate the expansion of this distribution and consequently the potential spread into Europe should not be overlooked. ...
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...
This study presents the first investigation of West Nile virus (WNV) seroprevalence among farmed horses in Kazakhstan. In 2024, a total of 368 serum samples were collected from horses across 106 settlements in 10 regions of the Republic of Kazakhstan. Using an enzyme-linked immunosorbent assay (ELISA), antibodies to WNV were detected in 32 horses (8.7%; 95% CI: 6.2-12.0%) from six regions. Among the seropositive animals, 26 (81.25%) were females and 6 (18.75%) were males, ranging in age from 1 to 19 years. No statistically significant association between sex and the presence of antibodies to W...
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...
Raftery AG, Gummery L, Garcia K, Mohite D, Capewell P, Sutton DGM.Equine trypanosomiasis is a neglected protozoal disease. Objective: To perform a systematic search of literature to explore: (1) In equines what is the global geographical distribution and prevalence of trypanosomiasis? In low and middle-income countries (LMICs) is trypanosomiasis more prevalent than in higher-income countries (HICs)? (2) Is trypanosomiasis infection a significant contributor to global morbidity and mortality? Methods: Systematic review and meta-analyses. Methods: Studies were identified that described naturally occurring equine trypanosomiasis worldwide following 'Preferred R...
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...
Badr C, Handous M, Nsiri J, ElBehi I, Arbi M, Maaroufi A, Bennour MA, Ben Osman R, Dachraoui K, Abbes M, Mahmoudi A, Khosrof I, Abrougui S, Lachheb J....West Nile virus (WNV) is an arthropod borne virus, the most widely distributed of the encephalitic Orthoflaviviruses. It can cause severe neurological symptoms in both humans and horses. It poses an emerging threat to both public and animal health. In this study, we retrospectively screened 25 suspected WNV samples collected from 2018 to 2023. Methods: A total number of 25 samples (brain tissue and blood) were collected from clinically affected horses and those already deceased across several locations in Tunisia. All samples were tested for the presence of WNV NS2A gene using qRT-PCR. Eleven ...
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...
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...
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...
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 () , ...
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 ...
Uilenberg G.The history of the genus Babesia is briefly outlined. The classical differences with the main other genus of non-pigment-forming hemoparasites, Theileria, are the absence of extra-erythrocytic multiplication (schizogony) in Babesia and the cycle in the vector tick, which includes transovarial transmission in Babesia but only transstadial transmission in Theileria. Also, the multiplication in the red cell of Babesia, by budding, most often results in two daughter cells (merozoites), while that of Theileria gives four merozoites, often as a Maltese cross. In particular this means that what is st...
Woldehiwet Z.Anaplasma phagocytophilum is the recently designated name replacing three species of granulocytic bacteria, Ehrlichia phagocytophila, Ehrlichia equi and the agent of human granulocytic ehrlichiosis, after the recent reorganization of the families Rickettsiaceae and Anaplasmataceae in the order Rickettsiales. Tick-borne fever (TBF), which is caused by the prototype of A. phagocytophilum, was first described in 1932 in Scotland. A similar disease caused by a related granulocytic agent was first described in horses in the USA in 1969; this was followed by the description of two distinct granulocy...
Calisher CH.Of more than 500 arboviruses recognized worldwide, 5 were first isolated in Canada and 58 were first isolated in the United States. Six of these viruses are human pathogens: western equine encephalitis (WEE) and eastern equine encephalitis (EEE) viruses (family Togaviridae, genus Alphavirus), St. Louis encephalitis (SLE) and Powassan (POW) viruses (Flaviviridae, Flavivirus), LaCrosse (LAC) virus (Bunyaviridae, Bunyavirus), and Colorado tick fever (CTF) virus (Reoviridae, Coltivirus). Their scientific histories, geographic distributions, virology, epidemiology, vectors, vertebrate hosts, transm...
Weaver SC, Salas R, Rico-Hesse R, Ludwig GV, Oberste MS, Boshell J, Tesh RB.Venezuelan equine encephalomyelitis (VEE) virus has caused periodic epidemics among human beings and equines in Latin America from the 1920s to the early 1970s. The first major outbreak since 1973 occurred in Venezuela and Colombia during 1995, and involved an estimated 75,000 to 100,000 people. We report an epidemiological and virological investigation of this epidemic. Methods: Virus isolates were made in cell culture from human serum, human throat swabs, and brain tissue from aborted and stillborn human fetuses, as well as from horse brain tissue and pooled mosquito collections. Human sera ...
Sangioni LA, Horta MC, Vianna MC, Gennari SM, Soares RM, Galvão MA, Schumaker TT, Ferreira F, Vidotto O, Labruna MB.We compared the rickettsial infection status of Amblyomma cajennense ticks, humans, dogs, and horses in both Brazilian spotted fever (BSF)-endemic and -nonendemic areas in the state of Sao Paulo, Brazil. Most of the horses and few dogs from BSF-endemic areas had serologic titers against Rickettsia rickettsii antigens. In contrast, no dogs or horses from BSF-nonendemic areas had serologic titers against R. rickettsii antigens, although they were continually exposed to A. cajennense ticks. All human serum samples and ticks from both areas were negative by serologic assay and polymerase chain rea...
Maclachlan NJ, Guthrie AJ.Arthropod-transmitted viruses (Arboviruses) are important causes of disease in humans and animals, and it is proposed that climate change will increase the distribution and severity of arboviral diseases. Orbiviruses are the cause of important and apparently emerging arboviral diseases of livestock, including bluetongue virus (BTV), African horse sickness virus (AHSV), equine encephalosis virus (EEV), and epizootic hemorrhagic disease virus (EHDV) that are all transmitted by haematophagous Culicoides insects. Recent changes in the global distribution and nature of BTV infection have been espec...
Murgue B, Murri S, Zientara S, Durand B, Durand JP, Zeller H.On September 6, 2000, two cases of equine encephalitis caused by West Nile (WN) virus were reported in southern France (Hérault Province), near Camargue National Park, where a WN outbreak occurred in 1962. Through November 30, 76 cases were laboratory confirmed among 131 equines with neurologic disorders. The last confirmed case was on November 3, 2000. All but three cases were located in a region nicknamed "la petite Camargue," which has several large marshes, numerous colonies of migratory and resident birds, and large mosquito populations. No human case has been confirmed among clinically ...
Habarugira G, Suen WW, Hobson-Peters J, Hall RA, Bielefeldt-Ohmann H.West Nile virus (WNV) is an important zoonotic flavivirus responsible for mild fever to severe, lethal neuroinvasive disease in humans, horses, birds, and other wildlife species. Since its discovery, WNV has caused multiple human and animal disease outbreaks in all continents, except Antarctica. Infections are associated with economic losses, mainly due to the cost of treatment of infected patients, control programmes, and loss of animals and animal products. The pathogenesis of WNV has been extensively investigated in natural hosts as well as in several animal models, including rodents, lagom...
Murray KO, Mertens E, Despres P.Zoonotic West Nile virus (WNV) circulates in natural transmission cycles involving certain mosquitoes and birds, horses, humans, and a range of other vertebrates are incidental hosts. Clinical infections in humans can range in severity from uncomplicated WNV fever to fatal meningoencephalitis. Since its introduction to the Western Hemisphere in 1999, WNV had spread across North America, Central and South America and the Caribbean, although the vast majority of severe human cases have occurred in the United States of America (USA) and Canada. By 2002-2003, the WNV outbreaks have involved thousa...
Baldacchino F, Desquesnes M, Mihok S, Foil LD, Duvallet G, Jittapalapong S.Tabanids are nuisance pests for people and livestock because of their painful and irritating bite, persistent biting behavior, and blood ingestion. About 4400 tabanid species have been described; they are seasonally present in all kinds of landscapes, latitudes, and altitudes. High populations have a significant economic impact on outdoor activities, tourism, and livestock production. Tabanids are also vectors of animal disease agents, including viruses, bacteria and parasites. However, tabanids have received little attention in comparison with other hematophagous Diptera. Here, we highlight t...
Savini G, Afonso A, Mellor P, Aradaib I, Yadin H, Sanaa M, Wilson W, Monaco F, Domingo M.Epizootic haemorrhagic disease (EHD) is an infectious non-contagious viral disease transmitted by insects of the genus Culicoides which affects wild and domestic ruminants. The causative agent, the epizootic haemorrhagic disease virus (EHDV), belongs to the family Reoviridae, genus Orbivirus and shares many morphological and structural characteristics with the other members of the genus such as bluetongue, African horse sickness and equine encephalosis viruses. In recent years EHD outbreaks have been reported in countries bordering the European Union. They caused disease in cattle and severe r...
Scoles GA, Ueti MW.Equine piroplasmosis is a disease of Equidae, including horses, donkeys, mules, and zebras, caused by either of two protozoan parasites, Theileria equi or Babesia caballi. These parasites are biologically transmitted between hosts via tick vectors, and although they have inherent differences they are categorized together because they cause similar pathology and have similar morphologies, life cycles, and vector relationships. To complete their life cycle, these parasites must undergo a complex series of developmental events, including sexual-stage development in their tick vectors. Consequentl...
Rivas F, Diaz LA, Cardenas VM, Daza E, Bruzon L, Alcala A, De la Hoz O, Caceres FM, Aristizabal G, Martinez JW, Revelo D, De la Hoz F, Boshell J....In 1995, the first Venezuelan equine encephalitis (VEE) outbreak in Colombia in 22 years caused an estimated 75,000 human cases, 3000 with neurologic complications and 300 fatal, in La Guajira State. Of the state's estimated 50,000 equines, 8% may have died. An epizootic IC virus, probably introduced from Venezuela, was rapidly amplified among unvaccinated equines. Record high rainfall, producing high densities of vector Aedes taeniorhynchus, led to extensive epidemic transmission (30% attack rate) in the four affected municipalities. Native Wayuu Indians, constituting 24% of the state's popul...
Castillo-Olivares J, Wood J.West Nile virus (WNV) is a flavivirus closely related to Japanese encephalitis and St. Louis encephalitis viruses that is primarily maintained in nature by transmission cycles between mosquitoes and birds. Occasionally, WNV infects and causes disease in other vertebrates, including humans and horses. West Nile virus has re-emerged as an important pathogen as several recent outbreaks of encephalomyelitis have been reported from different parts of Europe in addition to the large epidemic that has swept across North America. This review summarises the main features of WNV infection in the horse, ...
Carrera JP, Forrester N, Wang E, Vittor AY, Haddow AD, López-Vergès S, Abadía I, Castaño E, Sosa N, Báez C, Estripeaut D, Díaz Y, Beltrán D....The eastern equine encephalitis (EEE) and Venezuelan equine encephalitis (VEE) viruses are pathogens that infect humans and horses in the Americas. Outbreaks of neurologic disease in humans and horses were reported in Panama from May through early August 2010. Methods: We performed antibody assays and tests to detect viral RNA and isolate the viruses in serum samples from hospitalized patients. Additional cases were identified with enhanced surveillance. Results: A total of 19 patients were hospitalized for encephalitis. Among them, 7 had confirmed EEE, 3 had VEE, and 1 was infected with both ...
Valerio L, Marini F, Bongiorno G, Facchinelli L, Pombi M, Caputo B, Maroli M, Della Torre A.Knowledge of the frequency of contact between a mosquito species and its different hosts is essential to understand the role of each vector species in the transmission of diseases to humans and/or animals. However, no data are so far available on the feeding habits of Aedes albopictus in Italy or in other recently colonized temperate regions of Europe, due to difficulties in collecting blood-fed females of this diurnal and exophilic species. We analyzed Ae. albopictus host-feeding patterns in two urban and two rural sites within the area of Rome (Italy). Ae. albopictus was collected using stic...
Onyiche TE, Suganuma K, Igarashi I, Yokoyama N, Xuan X, Thekisoe O.Equine Piroplasmosis (EP) is a tick-borne disease caused by apicomplexan protozoan parasites, and . The disease is responsible for serious economic losses to the equine industry. It principally affects donkeys, horses, mules, and zebra but DNA of the parasites has also been detected in dogs and camels raising doubt about their host specificity. The disease is endemic in tropical and temperate regions of the world where the competent tick vectors are prevalent. Infected equids remain carrier for life with infection, whilst, infection with is cleared within a few years. This review focuses on...
Journal of medical entomologyOctober 5, 2006
Volume 43, Issue 5 936-946 doi: 10.1603/0022-2585(2006)43[936:hbahba]2.0.co;2
Balenghien T, Fouque F, Sabatier P, Bicout DJ.After 35 yr of disease absence, West Nile virus (family Flaviviridae, genus Flavivirus, WNV) circulation has been regularly detected in the Camargue region (southern France) since 2000. WNV was isolated from Culex modestus Ficalbi, which was considered the main vector in southern France after horse outbreaks in the 1960s. Recent WNV transmissions outside of the Cx. modestus distribution suggested the existence of other vectors. To study potential WNV vectors, horse- and bird-baited traps and human landing collections of mosquitoes were carried out weekly from May to October 2004 at two Camargu...
Blitvich BJ.West Nile virus (WNV) is a flavivirus that is maintained in a bird-mosquito transmission cycle. Humans, horses and other non-avian vertebrates are usually incidental hosts, but evidence is accumulating that this might not always be the case. Historically, WNV has been associated with asymptomatic infections and sporadic disease outbreaks in humans and horses in Africa, Europe, Asia and Australia. However, since 1994, the virus has caused frequent outbreaks of severe neuroinvasive disease in humans and horses in Europe and the Mediterranean Basin. In 1999, WNV underwent a dramatic expansion of ...
Komar N.West Nile virus (WNV) has emerged in recent years in temperate regions of Europe and North America, presenting a threat to both public and animal health. The most serious manifestation of infection is fatal encephalitis in humans and horses, as well as mortality in certain domestic and wild birds. A recent development in the epizootiology of this mosquito-borne flavivirus was the occurrence of a severe outbreak in New York City and surrounding areas. During this outbreak, mortality was observed in humans, horses, a cat and numerous species of wild birds, particularly members of the family Corv...
van der Meulen KM, Pensaert MB, Nauwynck HJ.West Nile virus (WNV), an arthropod-borne virus belonging to the family Flaviviridae, had been recognized in Africa, Asia and the south of Europe for many decades. Only recently, it has been associated with an increasing number of outbreaks of encephalitis in humans and equines as well as an increasing number of infections in vertebrates of a wide variety of species. In this article, the data available on the incidence of WNV in vertebrates are reviewed. Moreover, the role of vertebrates in the transmission of WNV, the control of WNV infections in veterinary medicine as well as future perspect...
Cupp EW, Zhang D, Yue X, Cupp MS, Guyer C, Sprenger TR, Unnasch TR.Uranotaenia sapphirina, Culex erraticus, and Cx. peccator were collected in an enzootic eastern equine encephalomyelitis (EEE) virus focus in central Alabama (Tuskegee National Forest) from 2001 to 2003 and analyzed for virus as well as host selection. EEE virus was detected in each species every year except 2003, when pools of Cx. peccator were negative. Most (97%) of the 130 Cx. peccator blood meals identified were from ectothermic hosts; 3% were from birds. Among blood meals from reptiles (approximately 75% of the total), 81% were from Agkistrodon piscivorus (cottonmouth); all amphibian blo...
Marfin AA, Gubler DJ.In 1999, an epidemic of West Nile virus (WNV) encephalitis occurred in New York City (NYC) and 2 surrounding New York counties. Simultaneously, an epizootic among American crows and other bird species occurred in 4 states. Indigenous transmission of WNV had never been documented in the western hemisphere until this epidemic. In 2000, the epizootic expanded to 12 states and the District of Columbia, and the epidemic continued in NYC, 5 New Jersey counties, and 1 Connecticut county. In addition to these outbreaks, several large epidemics of WNV have occurred in other regions of the world where t...
Paz S, Malkinson D, Green MS, Tsioni G, Papa A, Danis K, Sirbu A, Ceianu C, Katalin K, Ferenczi E, Zeller H, Semenza JC.In the summer of 2010, Europe experienced outbreaks of West Nile Fever (WNF) in humans, which was preceded by hot spells. The objective of this study was to identify potential drivers of these outbreaks, such as spring and summer temperatures, relative humidity (RH), and precipitation. Methods: Pearson and lag correlations, binary and multinomial logistic regressions were used to assess the relationship between the climatic parameters and these outbreaks. Results: For human morbidity, significant (<0.05) positive correlations were observed between a number of WNF cases and temperature, with...
Rizzo C, Napoli C, Venturi G, Pupella S, Lombardini L, Calistri P, Monaco F, Cagarelli R, Angelini P, Bellini R, Tamba M, Piatti A, Russo F, Palù G....In Italy a national Plan for the surveillance of imported and autochthonous human vector-borne diseases (chikungunya, dengue, Zika virus disease and West Nile virus (WNV) disease) that integrates human and veterinary (animals and vectors) surveillance, is issued and revised annually according with the observed epidemiological changes. Here we describe results of the WNV integrated veterinary and human surveillance systems in Italy from 2008 to 2015. A real time data exchange protocol is in place between the surveillance systems to rapidly identify occurrence of human and animal cases and to de...
Carpenter S, Mellor PS, Fall AG, Garros C, Venter GJ.African horse sickness virus (AHSV) is a lethal arbovirus of equids that is transmitted between hosts primarily by biting midges of the genus Culicoides (Diptera: Ceratopogonidae). AHSV affects draft, thoroughbred, and companion horses and donkeys in Africa, Asia, and Europe. In this review, we examine the impact of AHSV critically and discuss entomological studies that have been conducted to improve understanding of its epidemiology and control. The transmission of AHSV remains a major research focus and we critically review studies that have implicated both Culicoides and other blood-feeding...
Horta MC, Labruna MB, Pinter A, Linardi PM, Schumaker TT.This study investigated rickettsial infection in animals, humans, ticks, and fleas collected in five areas of the state of São Paulo. Eight flea species (Adoratopsylla antiquorum antiquorum, Ctenocephalides felis felis, Polygenis atopus, Polygenis rimatus, Polygenis roberti roberti, Polygenis tripus, Rhopalopsyllus lugubris, and Rhopalopsyllus lutzi lutzi), and five tick species (Amblyomma aureolatum, Amblyomma cajennense, Amblyomma dubitatum, Ixodes loricatus, and Rhipicephalus sanguineus) were collected from dogs, cats, and opossums. Rickettsia felis was the only rickettsia found infecting ...
Hassan HK, Cupp EW, Hill GE, Katholi CR, Klingler K, Unnasch TR.An important variable in the amplification and escape from the enzootic cycle of the arboviral encephalitides is the degree of contact between avian hosts and mosquito vectors. To analyze this interaction in detail, blood-fed mosquitoes that were confirmed vectors of eastern equine encephalomyelitis (EEE) virus were collected in 2002 from an enzootic site in central Alabama during the time this virus was actively transmitted. Avian-derived blood meals were identified to the species level of the host, and the proportion derived from each species was compared with the overall composition of the ...
Malkinson M, Banet C.Surveys on wild birds conducted during the last two decades in Europe, notably Poland and the Czech Republic, to determine their infection rate with WN virus have revealed endemic foci of infection. Some species of seropositive birds were nonmigrators while others were hatchlings of migrating species. Persistently infected avian reservoirs are potential sources of viruses for mosquitoes that multiply in the temperate European zone in hot, wet summers. In the past, evidence for geographical circulation of WN viruses was based on antigenic analysis of strains from different countries while more ...
