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.
Rabies surveillance in the United States during 2009. During 2009, 49 states and Puerto Rico reported 6,690 rabid animals and 4 human rabies cases to the CDC, representing a 2.2% decrease from the 6,841 rabid animals and 2 human cases reported in 2008. Approximately 92% of reported rabid animals were wildlife. Relative contributions by the major animal groups were as follows: 2,327 (34.8%) raccoons, 1,625 (24.3%) bats, 1,603 (24.0%) skunks, 504 (75%) foxes, 300 (4.5%) cats, 81 (1.2%) dogs, and 74 (1.1%) cattle. Compared with 2008, numbers of rabid raccoons and bats that were reported decreased, whereas numbers of rabid skunks, foxes, cats, cattle...
Evidence of multiple virulence subtypes in nosocomial and community-associated MRSA genotypes in companion animals from the upper midwestern and northeastern United States. Not much is known about the zoonotic transmission of methicillin-resistant Staphylococcus aureus (MRSA) in companion animals in the United States. We report the rate of prevalence of S. aureus and MRSA recovered from clinical samples of animals requiring treatment at veterinary clinics throughout the upper midwestern and northeastern United States. Methods: We compared phenotypes, genotypes, and virulence profiles of the MRSA isolates identified in companion animals, such as cats, dogs, horses, and pigs, with typical human nosocomial and community-associated MRSA (CA-MRSA) genotypes to assess ...
The prevalence of Cryptosporidium, and identification of the Cryptosporidium horse genotype in foals in New York State. To date, little is known about the prevalence, genotypes and zoonotic potential of Cryptosporidium spp. affecting horses, especially in North America. A cross-sectional study was conducted in New York, USA between February 25th and May 1st 2009. Fecal samples were collected from three hundred and forty nine 1-10-week-old foals and their dams on 14 different broodmare farms. All fecal samples were screened for Cryptosporidium spp. using a direct immunofluorescence assay (DFA). DNA extraction and PCR-RFLP analysis of the small-subunit (SSU) rRNA gene were performed on all the foal samples. PCR-p...
Salmonella enterica subsp. Enterica in Cattle Egret (Bubulcus ibis) chicks from central Texas: prevalence, serotypes, pathogenicity, and epizootic potential. Cattle Egrets have a worldwide distribution, feed in proximity to cattle and other domestic animals, and often nest in large colonies in urban woodlots. Over a 3-yr period, nestlings from five Cattle Egret colonies from Central Texas, USA, were surveyed for salmonellosis. Prevalence of infection ranged from 29% to 95%. Seventeen Salmonella enterica subsp. enterica serotypes were isolated, of which the 4,5,12:i-monophasic serotype predominated in cultures of both the digestive tract and pooled spleen and liver. Of 11 4,5,12:i-monophasic isolates phage typed, eight were determinate type 193. The...
Meningitis due to group C Streptococcus: a case report and review of the literature. Group C streptococci (GCS) are common causes of veterinary diseases and may colonize humans. Human diseases due to GCS are uncommon and generally occur in the elderly and persons exposed to animals or animal products. We report a case of Streptococcus equi subsp. zooepidemicus meningitis in a horse trainer and review 36 cases of GCS meningitis reported in the literature. The median age was 48 y and the majority of patients were previously healthy. Thirty-one percent (11/36) of the reported cases followed equine exposure and 19% (7/36) ingestion of dairy products. Sixty-seven percent (24/36) we...
Brazilian spotted fever in cart horses in a non-endemic area in Southern Brazil. Brazilian Spotted Fever (BSF) is an often fatal zoonosis caused by the obligate intracellular bacterium Rickettsia rickettsii. The disease is generally transmitted to humans by Amblyomma spp. ticks. Serological evidence of past infection by R. rickettsii has been reported in horses, but the pathogenicity of R. rickettsii in horses remains unknown. Cart horses are still widely used in urban and urban fringe areas in Brazil, and these animals may constitute suitable sentinels for BSF human in these areas, for example, in Sao Jose dos Pinhais, where the first BSF human case in the state of Parana...
Survey for tick-borne zoonoses in the state of Espirito Santo, southeastern Brazil. Blood samples collected from 201 humans, 92 dogs, and 27 horses in the state of Espirito Santo, Brazil, were tested by polymerase chain reaction, indirect immunofluorescence assays, and indirect enzyme-linked immunosorbent assay for tick-borne diseases (rickettsiosis, ehrlichiosis, anaplasmosis, borreliosis, babesiosis). Our results indicated that the surveyed counties are endemic for spotted fever group rickettsiosis because sera from 70 (34.8%) humans, 7 (7.6%) dogs, and 7 (25.9%) horses were reactive to at least one of the six Rickettsia species tested. Although there was evidence of ehrlic...
The utility of animal surveillance in the detection of West Nile virus activity in Puerto Rico, 2007. After the isolation of West Nile virus (WNV) from humans, mosquitoes, and chickens in 2007, an analysis of animal surveillance involving multiple species (horses, monkeys, sheep, dogs, and birds) used to track WNV transmission from 2006 to 2008 was performed. During this period 13.4% of all the animal samples collected were seropositive by blocking ELISA for WNV. The most complete island-wide sampling was obtained from horses of which 22% were serologically positive and 96% were confirmed as WNV infections by plaque-reduction neutralization test. Our conclusion from this 3-year study is that a...
Carriage of Clostridium difficile and other enteric pathogens among a 4-H avocational cohort. Clostridium difficile (CD), Salmonella, Campylobacter and enterohemorrhagic Escherichia coli (EHEC) are major causes of morbidity in a variety of enteric diseases in humans and animals, but subclinical carriage in both is probably more common than are clinical cases. Little is known regarding the prevalence of these pathogens in animals raised for exhibit at Michigan county fairs or the frequency with which Michigan citizens raising these animals may have been subclinically colonized. To address these issues, 361 fecal specimens from 158 humans and 203 of their farm animals were cultured for C...
A case of disseminated infection caused by Streptococcus equi subspecies zooepidemicus. Human infections with Streptococcus equi subspecies zooepidemicus, a group C streptococcus, are very rare and are generally associated with contact with horses, and consumption of unpasteurized milk products, goat cheese or pork. In most cases S zooepidemicus leads to fulminant infections. The case of a middle-aged woman who had sporadic contact with horses is described in the present report. She developed a bacteremia with severe and extensive complications that included meningitis, mitral endocarditis and blindness due to bilateral endophthalmitis. To the authors' knowledge, this is the firs...
Human meningitis from Streptococcus equi subsp. zooepidemicus acquired as zoonoses. Streptococcus equi subsp. zooepidemicus rarely causes meningitis in humans by contact with domestic animals or their unpasteurized products. In this paper we reviewed the literature pertaining to the epidemiological and clinical aspects relating to this infection on previously reported cases of human disease. Additionally, the case of a 51-year-old female who acquired meningitis with this organism after contact with a horse is described. This patient was successfully treated with ceftriaxone, yet penicillin remains the treatment of choice. This aetiological agent should be considered in the pr...
Animal and human rabies in Mongolia. The prevalence of animal rabies differs in each area of Mongolia. Wolves (Canis lupus Linnaeus, 1758), foxes ( Vulpes vulpes Linnaeus, 1758), corsac foxes (Vulpes corsac Linnaeus, 1768) and manuls (Felis manul Pallas, 1778) are considered to be the infective wild animals in natural foci. Amongst livestock, cattle have had the most rabies cases, followed by camels, sheep, goats and horses. The peak prevalence of animal rabies occurred in the 1970s. Dundgovi Province had the highest incidence during that period. The number of rabies cases in animals decreased during the 1980s. This may have been...
West Nile virus circulation in Emilia-Romagna, Italy: the integrated surveillance system 2009. Following a large West Nile virus (WNV) epidemic in northeastern Italy in 2008, human and animal surveillance activities were implemented in Emilia Romagna. Human surveillance was performed by serology or genome detection on blood and cerebrospinal fluid for all suspected cases suffering from acute meningoencephalitis in the regional territory. Animal surveillance consisted of passive and active surveillance of horses and active surveillance of wild birds and mosquitoes. Between 15 June and 31 October 2009, nine of 78 possible cases of West Nile neuroinvasive disease were confirmed (three fata...
Antimicrobial resistance in equine faecal Escherichia coli isolates from North West England. Escherichia coli isolates of equine faecal origin were investigated for antibiotic resistance, resistance genes and their ability to perform horizontal transfer. Methods: In total, 264 faecal samples were collected from 138 horses in hospital and community livery premises in northwest England, yielding 296 resistant E. coli isolates. Isolates were tested for susceptibility to antimicrobial drugs by disc diffusion and agar dilution methods in order to determine minimum inhibitory concentrations (MIC). PCR amplification was used to detect genes conferring resistance to: ampicillin (TEM and SHV b...
Validation of a commercial enzyme immunoassay for detection of Clostridium difficile toxins in feces of horses with acute diarrhea. Clostridium difficile infection (CDI) is a recognized cause of colitis in the horse. Identification of its toxins is important for management of individual cases and for prevention of transmission and zoonosis. In humans, CDI diagnosis is performed with enzyme immunoassays, none of which have been validated for horses. Objective: (1) Establish which test for CDI diagnosis was more frequently used by diagnostic laboratories, (2) determine the identified test's performance, sensitivity, and specificity, and (3) validate its use in diarrheic horses. Methods: Samples were obtained from 72 horses p...
Re-emergence of glanders in India – Report of Maharashtra state. Glanders, a notifiable highly contagious disease primarily of equids, is a disease of high zoonotic importance. Caused by gram-negative bacillus, Burkholderia mallei, the disease was restricted to certain pockets of India with sporadic cases. Recently, a major outbreak of glanders occurred in India starting from Maharashtra. Following clinical signs and symptoms and laboratory investigations on serum, nasal swab and pus swab samples, it was confirmed as glanders among equines in Pune and Panchgani areas of Maharashtra. One pus sample and three nasal swabs yielded B. mallei isolates while 23 se...
A seroepidemiological study of exposure to Toxoplasma, Leishmania, Echinococcus and Trichinella in equids in Greece and analysis of risk factors. The role of horses in the transmission of parasitic zoonoses either as a source of infection to vectors or through contamination of definitive hosts is gaining importance worldwide. For this reason sera from 773 equids including 753 horses, 13 mules and seven ponies in four regions of Greece were investigated by ELISA for the presence of IgG antibodies against Toxoplasma, Leishmania, Echinococcus and Trichinella. Anti-Toxoplasma antibodies were detected in all regions with an overall prevalence of 1.8%. In contrast, antibodies to Leishmania, Echinococcus, and Trichinella were present only in h...
ELISA-seroprevalence of Toxoplasma gondii in draught horses in Greater Cairo, Egypt. Toxoplasma gondii is one of the important zoonotic parasites of worldwide. In this paper the seroprevalence of T. gondii in draught horses (3-15 years) including 90 males and 10 females in the first half of the year 2009 was studied. The result showed that the overall ELISA-T. gondii antibodies were 25% of the horses in Greater Cairo, 50% (females) and 22.2% (males).
Prevalence of methicillin-resistant Staphylococcus aureus colonization in horses in Saskatchewan, Alberta, and British Columbia. This study estimated the prevalence of methicillin resistant Staphylococcus aureus (MRSA) in nasal swabs of 458 horses in western Canada. The rate of colonization was 1.3% +/- 5.84% [95% confidence interval (CI)], a rate similar to those reported elsewhere. Colonization tended to be transient and seemed unrelated to stress or administration of antimicrobials. Five of the 6 isolates were Canadian epidemic MRSA-5, a human clone that appears to predominate in horses in North America. The other isolate was spa type 539 (t034), a sequence type 398 strain, and this is the first report of this clone ...
Methicillin-resistant staphylococci isolated from healthy horses and horse personnel in Italy. Methicillin-resistant staphylococci (MRS) were isolated from nasal swabs of 56 of 159 (35.2%; 95% confidence interval [CI]: 27.9-43.2%) healthy horses. Two nasal swabs were collected from each horse; 43 of 159 (27%; 95% CI: 20.5-34.8%) of the cohort were colonized by MRS strains in 1 nostril, while in the remaining 13 of 159 (8.2%; 95% CI: 4.6-13.9%), different or identical MRS strains were isolated in both nostrils. Of the 29 humans in close contact with the horses tested, 4 (13.8%; 95% CI: 4.5-32.6%) were found to be carriers of MRS. All isolates were coagulase negative with the exception of...
[Ehrlichiosis/Anaplasmosis]. Ehrlichiosis and anaplasmosis are zoonoses caused by bacteria from the family Anaplasmataceae, including human and animal pathogens. The human pathogens are Ehrlichia chaffeensis, the causative agent of human monocytic ehrlichiosis (HME), Anaplasma phagocytophilum, the pathogen causing human granulocytic anaplasmosis (HGA), E. ewingii and Neorickettsia sennetsu, granulocytotropic and monocytotropic Ehrlichia species, respectively. Ehrlichia spp. are small, gram-negative, obligate intracellular bacteria. They replicate in the cytoplasmic vacuoles of host cells, especially granulocytes and monoc...
Companion animals: a reservoir for methicillin-resistant Staphylococcus aureus in the community? This article reviews the literature on the epidemiology of methicillin-resistant Staphylococcus aureus (MRSA) in dogs, cats and horses. Over the past 10 years, MRSA has emerged as an important pathogen in veterinary medicine, especially in countries with a high MRSA burden in human hospitals. During the same period, community-associated MRSA (CA-MRSA) infections in humans without apparent links to healthcare facilities have increased dramatically. Although animal infections occur outside human hospitals, significant epidemiological, clinical and genetic differences exist between CA-MRSA in hum...
Echinococcus granulosus infection in humans and livestock in the Coquimbo region, north-central Chile. Cyst echinococcosis (CE) is one of the most important zoonosis in Chile, where studies have focussed mainly in moist southern regions. The present study was conducted to determine the prevalence of cystic echinococcosis (CE) in livestock and humans in the semiarid Coquimbo region in north-central Chile. A review of all surgical cases of CE in humans reported in the Elqui, Limarí and Choapa provinces in Coquimbo region for the period comprising 1995-2006 was obtained. In addition, a retrospective study of CE covering condemnation records from slaughterhouses of these provinces from the same pe...
A retrospective longitudinal study of animal and human rabies in Botswana 1989-2006. A longitudinal study of animal and human rabies covering 18 years from 1989 to 2006 was retrospectively conducted in order to highlight the epidemiological features and trends of the disease in Botswana. Over the 18-year period, a total of 4 306 brain specimens collected from various species of animals including human beings with clinical signs consistent with rabies were submitted to the National Veterinary Laboratory in Gaborone for confirmatory diagnosis. Of the samples submitted, 2419 cases were found to be positive for lyssavirus antigen; this presents an overall prevalence rate of 56.18 ...
Seroprevalence of Leptospira spp. in clinically healthy racing horses in Korea. Leptospirosis is a zoonotic disease of global importance, and has a worldwide distribution. The present study aimed to determine leptospiral seroprevalence in clinically healthy racing horses from all three racecourses in Korea. Serum samples from 1,226 racing horses were examined using a microscopic agglutination test to detect the presence of antibodies against 18 Leptospira serovars. Of the tested samples, 307 (25.0%) were found to be positive. The distribution of seroprevalence differed significantly by racecourse (P=0.004); the Jeju course had the highest incidence (31.1%), followed by th...
Epidemiological survey on equine cryptosporidium and giardia infections in Italy and molecular characterization of isolates. Cryptosporidium and Giardia are two of the most common enteric pathogens of domestic and wild animals and humans. However, little is known on the prevalence, clinical manifestations and economic and zoonotic significance of these infections in horses. This study was undertaken to investigate the prevalence, excretion patterns and risk factors related to the faecal shedding of Cryptosporidium oocysts and Giardia cysts in horses and the zoonotic potential of species/genotypes isolated. The survey was performed on 120 foals and 30 broodmares reared in five Italian farms. Foals were divided in fou...
Evolutionary patterns of eastern equine encephalitis virus in North versus South America suggest ecological differences and taxonomic revision. The eastern equine encephalitis (EEE) complex consists of four distinct genetic lineages: one that circulates in North America (NA EEEV) and the Caribbean and three that circulate in Central and South America (SA EEEV). Differences in their geographic, pathogenic, and epidemiologic profiles prompted evaluation of their genetic diversity and evolutionary histories. The structural polyprotein open reading frames of all available SA EEEV and recent NA EEEV isolates were sequenced and used in evolutionary and phylogenetic analyses. The nucleotide substitution rate per year for SA EEEV (1.2 x 10(-4...