Topic:Zoonotic Diseases
Zoonotic diseases are infectious diseases that can be transmitted between animals and humans, with horses acting as potential hosts or vectors. These diseases can result from various pathogens, including bacteria, viruses, parasites, and fungi, which can be transmitted through direct contact, vectors like mosquitoes, or environmental exposure. Horses can carry zoonotic pathogens such as Salmonella, West Nile Virus, and Leptospira, posing health risks to humans, particularly those working closely with equines. Understanding the transmission dynamics, prevention strategies, and control measures helps safeguard both equine and human health. This page compiles peer-reviewed research studies and scholarly articles that explore the epidemiology, pathogenesis, and management of zoonotic diseases associated with horses.
Ecological aspects of hendra virus. Hendra virus, a novel and fatally zoonotic member of the family Paramyxoviridae, was first described in Australia in 1994. Periodic spillover from its natural host (fruit bats) results in catastrophic disease in horses and occasionally the subsequent infection of humans. Prior to 2011, 14 equine incidents involving seven human cases (four fatal) were recorded. The year 2011 saw a dramatic departure from the sporadic incidents of the previous 16 years, with a cluster of 18 incidents in a single 3-month period. The fundamental difference in 2011 was the total number of incidents, the geographic ...
Henipaviruses in their natural animal hosts. Hendra virus (HeV) and Nipah virus (NiV) form a separate genus Henipavirus within the family Paramyxoviridae, and are classified as biosafety level 4 pathogens due to their high case fatality rate following human infection and because of the lack of effective vaccines or therapy. Both viruses emerged from their natural reservoir during the last decade of the twentieth century, causing severe disease in humans, horses and swine, and infecting a number of other mammalian species. The current review summarizes our up to date understanding of pathology and pathogenesis in the natural reservoir spe...
The role of horses in the transmission of leptospirosis in an urban tropical area. The objective of this study was to demonstrate the presence of leptospires in equine urine, as evidence for a potential role of horses in transmission of this organism. Thoroughbred horses (aged 2-5 years, n = 276) from Rio de Janeiro, Brazil, were studied. After a severe storm, the premises of the animals remained flooded for 72 h. Blood samples for serology were collected on days 20 and 35 (day of storm = day 0). On day 20, 132 (47·8%) horses were seroreactive (titre ≥200) and, of these, 23 (31·0%) had increased antibody titres on day 35. Furthermore, 34 urine samples (for PCR and cultur...
Anaplasma phagocytophilum seroprevalence in equids: a survey in Sicily (Italy). This study was undertaken to determine the prevalence of Anaplasma phagocytophilum infection in Equidae and investigate the possibility of exposure to the organism in Sicily (Southern Italy). During the study blood samples were collected in horses and donkeys housed in five of the nine provinces of Sicilian Island. Of 133 horses and 100 donkeys tested, respectively 9.0% and 6.0% were seroactive (IFAT) with A. phagocytophilum antigen. In only 4.7% of the horses, specific A. phagocytophilum DNA was recorded; in donkey, Anaplasma DNA was not found. Our results indicate a low prevalence of A. phag...
Seroprevalence of Toxoplasma gondii in Sheep, Cattle and Horses in Urmia North-West of Iran. Toxoplasma gondii is a zoonotic protozoan parasite found worldwide and responsible for major economic losses in most classes of livestock. This study was aimed to determine the prevalence of T. gondii infection in sheep, cattle and horses in Urmia, north-west of Iran, using MAT. Methods: Blood samples of 276 livestock and 26 horses were collected from July 2009 till April 2010. The data were analyzed by the Chi-square, Fisher's Exact and Cochran's and Mantel-Haenszel Tests. The level of significance was set at P<0.05. Results: Thirty-three (21.1%) sheep, 2 (1.6%) cattle and 3 (11.5%) horses...
A serological survey of cystic echinococcosis in equids in East of Turkey. Cystic echinococcosis (CE), caused by hydatid cysts, is a widespread and hazardous disease in humans and animals worldwide. The disease is very common in Turkey, causing serious economic losses and public health problem. In this study, the seroprevalence of equine CE was determined by enzyme-linked immunosorbent assay (ELISA). Methods: Partially purified cyst fluid antigen from sheep hydatid cyst fluid was used as antigen in ELISA. A total of 250 equids consisting of 206 donkeys and 44 horses from various regions of Erzurum province of Eastern Turkey. Results: Anti- Echinococcus granulosus ant...
Seroprevalence of Toxoplasma gondii in equids from Southern Spain. Antibodies to Toxoplasma gondii were determined in serum samples from 616 equids (454 horses, 80 mules and 82 donkeys) in a cross-sectional study of 420 herds in Andalusia (Southern Spain), the region with the highest number of equids in Spain. Antibodies to T. gondii were found in 10.8% horses, 15.0% mules and 25.6% donkeys by using the modified agglutination test (MAT) at a cut-off of 1:25. Herd seroprevalence for horses, mules and donkeys was 14.7% (48/327), 23.9% (11/46) and 34.0% (16/47), respectively, and 75 herds (17.8%) had at least one seropositive animal. Significant differences in T...
Isolation of Cronobacter spp. (formerly Enterobacter sakazakii) from nostrils of healthy stable horse–short communication. Cronobacter spp. belongs to the family Enterobacteriaceae. It is a motile (peritricha) Gram-negative non-spore forming bacterium. At present, Enterobacter sakazakii is reported as a Cronobacter spp. species with 16 biogroups. It is a ubiquitous organism whose isolation used to be associated with a contaminated powdered infant formula and feed for neonates and infants. Information about the Cronobacter spp. species incidence in the environment, its potential dissemination and its vectors, is very limited. The authors have documented incidence of Cronobacter spp. in the nostril mucous membrane o...
Hendra virus detection using Loop-Mediated Isothermal Amplification. Hendra virus (HeV) is a zoonotic paramyxovirus endemic in Australian Pteropus bats (fruit bats or flying foxes). Although bats appear to be unaffected by the virus, HeV can spread from fruit bats to horses, causing severe disease. Human infection results from close contact with the blood, body fluids and tissues of infected horses. HeV is a biosecurity level 4 (BSL-4) pathogen, with a high case-fatality rate in humans and horses. Current assays for HeV detection require complex instrumentation and are generally time consuming. The aim of this study was to develop a Loop-Mediated Isothermal Amp...
Monitoring of the West Nile virus epidemic in Spain between 2010 and 2011. West Nile virus (WNV) is a mosquito-transmitted flavivirus recognized as an emerging and re-emerging pathogen in different countries. This study describes the monitoring of the first WNV epidemic in Spain between 2010 and 2011. Between September and December 2010, 36 outbreaks of WNV in horses were reported in three different provinces of Andalusia (southern Spain), with no apparent spread outside this area. The temporal distribution and the clinical signs observed during the WNV epidemic in Spain were, in general, similar to those reported in Europe and in the Mediterranean Basin. Morbidity, ...
Veterinary Vaccines and Their Importance to Animal Health and Public Health. Veterinary vaccines have had, and continue to have, a major role in protecting animal health and public health, reducing animal suffering, enabling efficient production of food animals to feed the burgeoning human population, and greatly reducing the need for antibiotics to treat food and companion animals. Prominent examples include rabies vaccines and rinderpest vaccines. Rabies vaccines for domestic animals and wildlife have nearly eliminated human rabies in developed countries. Thanks to the Global Rinderpest Eradication Program which involves vaccination, trade restrictions, and surveilla...
West Nile fever outbreak in horses and humans, Spain, 2010. TO THE EDITOR: West Nile virus (WNV) is a member of the genus Flavivirus within the Japanese encephalitis antigenic complex. The enzootic virus cycle involves transmission between avian hosts and ornithophilic mosquitoes, whereas humans and horses are considered dead-end hosts. Given the recent increase of WNV infection in humans and horses in Europe, concern has been raised regarding public and animal health.
Experimental infection of horses with Hendra virus/Australia/horse/2008/Redlands. Hendra virus (HeV) is a highly pathogenic zoonotic paramyxovirus harbored by Australian flying foxes with sporadic spillovers directly to horses. Although the mode and critical control points of HeV spillover to horses from flying foxes, and the risk for transmission from infected horses to other horses and humans, are poorly understood, we successfully established systemic HeV disease in 3 horses exposed to Hendra virus/Australia/Horse/2008/Redlands by the oronasal route, a plausible route for natural infection. In 2 of the 3 animals, HeV RNA was detected continually in nasal swabs from as ea...
Seroprevalence of Toxoplasma gondii in domestic and wild animals from the Fernando de Noronha, Brazil. Fernando de Noronha is an archipelago of 21 islands and islets in the Atlantic Ocean, state of Pernambuco, Brazil, which has a varied biodiversity including alien species or sinantropic animals. The objective here was to determine the seroprevalence of Toxoplasma gondii in domestic and wild animals from Fernando de Noronha archipelago, Brazil. Between July 2007 and May 2010, blood samples were collected from 764 animals (533 domestic and 231 wild animals). Sera were tested by the indirect fluorescence antibody test (IFAT) or the modified agglutination test (MAT), or by both. Antibodies to T. g...
Hendra virus infection dynamics in Australian fruit bats. Hendra virus is a recently emerged zoonotic agent in Australia. Since first described in 1994, the virus has spilled from its wildlife reservoir (pteropid fruit bats, or 'flying foxes') on multiple occasions causing equine and human fatalities. We undertook a three-year longitudinal study to detect virus in the urine of free-living flying foxes (a putative route of excretion) to investigate Hendra virus infection dynamics. Pooled urine samples collected off plastic sheets placed beneath roosting flying foxes were screened for Hendra virus genome by quantitative RT-PCR, using a set of primers a...
Grazing Effects on Deer Mice with Implications to Human Exposure to Sin Nombre Virus. We examined the effects of grazing on deer mouse () movements into buildings using passive integrated transponder (PIT) technology and small simulated buildings located on 0.6-ha treatment (grazing) and control (no grazing) plots. Twelve experimental 9-day trials were conducted over the course of the study. During these trials, mouse movements into buildings were monitored during three time periods (each 3 days in length). In the treatment plots these time periods corresponded to pre-grazing, grazing, and post grazing by horses. The number of individual deer mice entering buildings over time d...
A preliminary study of Salmonella, verocytotoxigenic Escherichia coli/Escherichia coli O157 and Campylobacter on four mixed farms. The aims of this study were to investigate the incidence of Salmonella, verocytotoxigenic Escherichia coli (VTEC)/Escherichia coli O157 and Campylobacter on four mixed farms and to characterize the isolates in terms of a range of virulence factors. Eighty-nine composite (five different samples from the same animal species combined) faecal [cattle (24), pigs (14), sheep (4), poultry (4), horses (7), deer (4), dogs (9), rodents (2) and wild birds (20)] samples, 16 composite soil samples plus 35 individual water samples were screened using culture-based, immunomagnetic separation and molecular me...
Spatial association and clinical development of equine influenza in horses yarded overnight at an equestrian event at Maitland prior to propagating the 2007 epidemic in Australia. The interaction and stabling of horses at equine events may have a substantial impact on the spread of a zoonotic disease. This study aimed to investigate the spread of equine influenza (EI) at an equestrian event at the start of the Australian outbreak. Around one-third of the competing horses were stabled overnight at the event and, of these, 70% developed symptoms of EI within 7 days. The index case was never positively identified, but stabling position and disease onset provided clues to its potential identity.
Endovascular aortic stent graft infection with Streptococcus equi: the first documented case. Streptococcus equi is a common equine infectious disease, but transmission to man is rare and confined to those who commonly come into close contact with horses. Similarly, prosthetic stent graft infection is a rare complication of endovascular aortic aneurysm repair. We describe the first reported case of aortic stent graft with S. equi occurring in a professional racehorse trainer. Clinical presentation, investigations, imaging and management of this case are described. In conclusion, clinicians should consider infection with rare organisms in patients with prosthetic implants who regularly ...
Use of a recombinant burkholderia intracellular motility a protein for immunodiagnosis of glanders. Glanders, caused by the Gram-negative, nonmotile bacterium Burkholderia mallei, is a contagious and highly fatal disease of equines. During the last decade, the number of glanders outbreaks has increased steadily. The disease also has high zoonotic significance and B. mallei is listed biological warfare agent. The complement fixation test (CFT) is a routinely used and internationally recognized test to screen equine sera for the glanders. However, discrepant results have been observed using the CFT. The low sensitivity and specificity of the CFT and enzyme-linked immunosorbent assay (ELISA) ha...
Exposure of free-ranging wild carnivores, horses and domestic dogs to Leptospira spp in the northern Pantanal, Brazil. Leptospirosis is a zoonotic disease affecting most mammals and is distributed throughout the world. Several species of domestic and wild animals may act as reservoirs for this disease. The purpose of this study was to assess the exposure of free-ranging wild carnivores, horses and domestic dogs on a private reserve located in the northern Pantanal (Brazil) and the surrounding areas to Leptospira spp from 2002-2006, 75 free-ranging wild carnivores were captured in the Pantanal and serum samples were collected. In addition, samples from 103 domestic dogs and 23 horses in the region were collecte...
Infection of dogs with equine influenza virus: evidence for transmission from horses during the Australian outbreak. During the equine influenza (EI) outbreak, respiratory disease was observed in dogs that were in close proximity to infected horses. Investigations were undertaken to exclude influenza virus infection. Of the 23 dogs that were seropositive in tests using the influenza A/Sydney/2007 virus as the test antigen, 10 showed clinical signs. EI virus appeared to be readily transmitted to dogs that were held in close proximity to infected horses, but there was no evidence of lateral transmission of the virus to other dogs that did not have contact with or were not held in close proximity to horses.
Acinetobacter baumannii isolates from pets and horses in Switzerland: molecular characterization and clinical data. We investigated whether Acinetobacter baumannii isolates of veterinary origin shared common molecular characteristics with those described in humans. Methods: Nineteen A. baumannii isolates collected in pets and horses were analysed. Clonality was studied using repetitive extragenic palindromic PCR (rep-PCR) and multilocus sequence typing (MLST). PCR and DNA sequencing for various β-lactamase, aminoglycoside-modifying enzyme, gyrA and parC, ISAba1 and IS1133, adeR and adeS of the AdeABC efflux pump, carO porin and class 1/2/3 integron genes were performed. Results: Two main clones [A (n =...
A recombinant Hendra virus G glycoprotein-based subunit vaccine protects ferrets from lethal Hendra virus challenge. The henipaviruses, Hendra virus (HeV) and Nipah virus (NiV), are two deadly zoonotic viruses for which no vaccines or therapeutics have yet been approved for human or livestock use. In 14 outbreaks since 1994 HeV has been responsible for multiple fatalities in horses and humans, with all known human infections resulting from close contact with infected horses. A vaccine that prevents virus shedding in infected horses could interrupt the chain of transmission to humans and therefore prevent HeV disease in both. Here we characterise HeV infection in a ferret model and show that it closely mirror...
Immunoglobulin G antibody profiles against Anopheles salivary proteins in domestic animals in Senegal. Although domestic animals may not be permissive for Plasmodium, they could nevertheless play a role in the epidemiology of malaria by attracting Anopheles away from humans. To investigate interactions between domestic animals and mosquitoes, we assayed immunoglobulin G (IgG) antibodies directed against the salivary proteins of Anopheles gambiae in domestic animals living in Senegalese villages where malaria is endemic. By Western blotting, sera from bovines (n=6), ovines (n=36), and caprines (n=36) did not react with Anopheles whole saliva. In contrast, equine sera recognized proteins in both ...
Cryptosporidium parvum infection in a mare and her foal with foal heat diarrhoea. Cryptosporidium infection was molecularly investigated in mares and in their neonatal foals for which the occurrence of foal heat diarrhoea was also assessed. Thirty-seven mare/foal pairs were included in the study. All foals were born in the same stud farm during 2006-2008 breeding seasons. Two faecal samples, one prior to and one after delivery were collected from each mare, whereas three faecal samples were taken from each foal, i.e. at 8, 10 and 12 days of age. All samples (74 from mares and 111 from foals) were divided into two aliquots, one of which was examined for the presence of Crypt...
Prevalence of methicillin-resistant Staphylococci on a farm: staff can harbour MRS when animals do not. The aim of this work was to establish the prevalence of methicillin-resistant Staphylococci (MRS) in the animals and staff of a teaching and research farm. Samples of dairy cattle (36), beef cattle (26), sheep (19), horses (21), pigs (23), goats (23) and humans (13) were collected and screened for the presence of MRS. The detection of mecA gene was performed by PCR to determine the resistance of the samples to methicillin. Antimicrobial-resistance testing to penicillin, meropenem, ceftriaxone, cephalothin, oxacillin, levofloxacin, enrofloxacin, chloramphenicol, ciprofloxacin, gentamicin, clind...