Topic:Vaccination
Vaccination in horses involves the administration of antigenic material to stimulate an immune response, providing protection against specific infectious diseases. This process is a key component of preventive equine healthcare, aiming to reduce the incidence and severity of illnesses such as equine influenza, tetanus, and West Nile virus. Vaccines can be administered via various routes and may contain live attenuated, inactivated, or subunit components. The immune response elicited by vaccination helps in the development of immunological memory, enabling horses to respond more effectively upon exposure to the actual pathogen. This page compiles peer-reviewed research studies and scholarly articles that explore the development, efficacy, and safety of vaccines in equine populations.
Altered immune responses to a heterologous protein in ponies with heavy gastrointestinal parasite burdens. This study was performed to test the hypothesis that immunity to heterologous vaccination would improve when the parasites were removed. It was also expected that parasitised ponies would exhibit a biased Th2 cytokine response to KLH immunisation. Helminth parasites are common in horses even in the era of highly effective broad-spectrum antiparasiticides. These parasites have been shown to alter the outcome to heterologous immunisation in a number of host species. The effect of gastrointestinal parasites on heterologous vaccination has not been addressed in equids. In the current study, humora...
Duration of immunity induced by an adjuvanted and inactivated equine influenza, tetanus and equine herpesvirus 1 and 4 combination vaccine. An adjuvanted vaccine containing inactivated equine influenza, herpesvirus antigens, and tetanus toxoid was administered to young seronegative foals of 8 months of age by deep intramuscular injection in the neck (Group A). The first two vaccinations were given 4 weeks apart. The third was administered 6 months later. Another group of foals (Group B) was vaccinated according to the same scheme at the same time with monovalent equine herpes virus (EHV) vaccine (EHV1.4) vaccine. Antibody responses to the equine influenza (single radial haemolysis; SRH) and tetanus (ToBi ELISA) components of the v...
Detection of antibodies to the nonstructural protein (NS1) of influenza A virus allows distinction between vaccinated and infected horses. Antibodies to the nonstructural protein (NS1) of A/equine/Miami/1/63 (H3N8) influenza virus were detected exclusively in the sera of mice experimentally infected with A/Aichi/2/68 (H3N2) and horses infected with A/equine/Kentucky/1/81 (H3N8) or A/equine/La Plata/1/93 (H3N8), but not in those of the animals immunized with the inactivated viruses, by enzyme-linked immunosorbent assay (ELISA) using a recombinant NS1 as antigen. The results indicate that the present method is useful for serological diagnosis to distinguish horses infected with equine H3 influenza viruses from those immunized with ...
Modelling the spread of a viral infection in equine populations managed in Thoroughbred racehorse training yards. A Monte Carlo model that simulates the management life cycle of a horse population in training on a Thoroughbred flat racing yard (i.e. stable) was developed for computer implementation. Each horse was characterised by several state variables. Discrete events at the horse level were triggered stochastically to reflect uncertainty about some input assumptions and heterogeneity of the horse population in a particular yard. This mathematical model was subsequently used to mimic the spread of equine influenza (EI) within a typical yard following the introduction of one or several infectious horses...
Application of a type-specific enzyme-linked immunosorbent assay for equine herpesvirus types 1 and 4 (EHV-1 and -4) to horse populations inoculated with inactivated EHV-1 vaccine. A type-specific enzyme-linked immunosorbent assay (ELISA) using equine herpesvirus types 1 (EHV-1) and 4 (EHV-4) glycoprotein G was applied for sero-epizootiology of EHV infections in Japan. Recently, an inactivated EHV-1 vaccine has been administered to racehorses for prevention of upper respiratory disease. To examine the effect of the vaccination on the result of the ELISA, 6 horses were experimentally inoculated three times intramuscularly or intranasally with inactivated EHV-1 vaccine. Sera collected from these horses were used to the type-specific ELISA and complement-fixation (CF) test....
Risk factors for equine influenza serum antibody titres in young thoroughbred racehorses given an inactivated vaccine. Young Thoroughbred racehorses (222 yearlings entering training and 246 2-year-old horses already in training) from eight flat-training yards in Newmarket, UK were used to monitor serological responses to vaccination with an inactivated influenza virus vaccine. Blood samples taken prior to and after vaccination were tested by single radial haemolysis (SRH) to determine antibody titres (expressed as area of haemolysis in mm(2)). Prior to vaccination, yearlings had mean antibody titres (64+/-4 mm(2)) that were approximately half of those of 2-year-olds (115+/-3 mm(2)) and 89% of yearlings and 73%...
[Veterinary service and supervision of equine competitions]. Because of the growing interest in animal health and welfare in breeding and sport--specially in the horse--the regulation of the German Riding Association (FN) was updated. The result--the LPO 2000--refer more functions to the veterinarian. At first the permanent presence of the vet is necessary, at second he controls the correct, new installed vaccination against influenza-virus. The functions of vet-check, general horse-control and doping are wide up in number and consultation. For this the veterinarian must decree about much experience and good preparation. The organisations of the veterin...
Equine vaccination. Equine infectious disease remains a constant and important threat to the health of domesticated horses. Vaccination plays a critical role in protecting against such disease, but at the present time the efficacy of some equine vaccination strategies is in doubt. The best strategy for resolving these concerns is an improved knowledge of the immunologic basis of successful vaccination, combined with the appropriate integration of effective vaccines into well-designed disease control policies.
[Relevance of infection with equine herpesvirus 1 (EHV-1) in a German thoroughbred stud: vaccination, abortion and diagnosis]. The aim of the present study was to clarify whether an EHV-1 induced abortion can be prognosticated by an increase of antibody titres, virus shedding and/or viraemia and whether the current abortion diagnostic is suitable. In this context the immune response post immunization and a possible reactivation were of great interest. For this purpose blood samples of 32 mares between the ages of 5-21 years were regularly investigated during a period of two years before and after vaccination and pregnancy. Neutralization tests, indirect immunofluorescence tests as well as PCR and virus isolation were ...
Risk factors for disease associated with influenza virus infections during three epidemics in horses. To identify risk factors associated with respiratory tract disease in horses during 3 epidemics caused by influenza virus infections. Methods: Cross-sectional and prospective longitudinal observational studies. Methods: 1,163 horses stabled at a Thoroughbred racetrack. Methods: Investigations were conducted during a 3-year period. An epidemic of respiratory tract disease caused by influenza virus infections was identified in each year. Routine observations and physical examinations were used to classify horses' disease status. Data were analyzed to identify factors associated with development ...
[Use of the immunoenzyme test ELISA-NS3 to distinguish horses infected by African horsesickness virus from vaccinated horses]. A vaccination protocol involving three horses, with five repeated injections of inactivated serotype 4 African horse sickness virus, was undertaken to determine a possible threshold for the appearance of antibodies against the non-structural protein NS3. Using an indirect enzyme-linked immunosorbent assay, with the recombinant NS3 protein as an antigen, the authors detected a response to NS3 as of the second injection for the first horse and after four injections for the second horse. No response to NS3 was detected for the third horse. The results show that the inactivated vaccine is insuffic...
Vaccination against lyme disease with recombinant Borrelia burgdorferi outer-surface protein A (rOspA) in horses. Eight 1-year-old ponies were vaccinated with recombinant OspA (ospA gene derived from B. burgdorferi B31) with adjuvant (aluminium hydroxide). Four ponies were used as non-vaccinated controls with adjuvant. One hundred and twelve days after the first vaccination, the vaccinated and non-vaccinated ponies were challenged by exposure to B. burgdorferi-infected adults tick (Ixodes scapularis) collected from Westchester County, New York (tick infection rate >/=60%). Protection from infection was evaluated by culture for B. burgdorferi from three monthly skin biopsies taken near the site of tick bit...
Epidemiological studies of equine herpesvirus 1 (EHV-1) in Thoroughbred foals: a review of studies conducted in the Hunter Valley of New South Wales between 1995 and 1997. Sero-epidemiological studies conducted between 1995 and 1997 on two large Thoroughbred stud farms in the Hunter Valley of NSW showed clear evidence of EHV-1 infection in foals as young as 30 days of age. Similarly, serological evidence suggested that these foals were infected with EHV-1 from their dams or from other lactating mares in the group, with subsequent foal to foal spread of infection prior to weaning. These studies also provided evidence of EHV-1 infection of foals at and subsequent to weaning, with foal to foal spread of EHV-1 amongst the weanlings. These data indicated that the mar...
Efficacy of a commercial vaccine for preventing disease caused by influenza virus infection in horses. To evaluate efficacy of a commercial vaccine for prevention of infectious upper respiratory tract disease (IURD) caused by equine influenza virus. Methods: Double-masked, randomized, controlled field trial. Methods: 462 horses stabled at a Thoroughbred racetrack. Methods: Vaccine or saline solution placebo was administered 4 times in the population at 6-week intervals. The vaccine contained 3 strains of inactivated influenza virus, and inactivated equine herpesvirus type 4. Horses received 1 or 2 doses of vaccine or placebo prior to onset of a natural influenza epidemic, and were examined 5 d/...
A particulate viral protein vaccine reduces viral load and delays progression to disease in immunized ponies challenged with equine infectious anemia virus. Immunization regimens that induce a broadly reactive cytolytic T lymphocyte (CTL) response specific for lentiviral antigens have emerged as the leading candidates in efficacy trials conducted in both animal modelshumans. To date, lentivirus vaccination strategies have overlooked one such immunization strategy, namely the use of particulate antigens. To evaluate the efficacy of targeting antigen into the phagocytic pathway to elicit a cell-mediated immune response to lentiviral antigens, we initiated the first study of a particulate-based vaccination protocol using a large animal model system. ...
Intestinal lesions in a horse associated with eastern equine encephalomyelitis virus infection. The primary lesions of eastern equine encephalomyelitis (EEE) virus infection in the horse are limited to the brain and spinal cord. Intestinal lesions in addition to the changes in the central nervous system were found in a 6-month-old male Tennessee Walking Horse. One week prior to death, this colt was vaccinated for EEE virus, western equine encephalomyelitis virus, influenza virus, equine rhinopneumonitis virus, and tetanus. The clinical signs consisted of ataxia and rear-end weakness, with a body temperature of 102.8 F. Gross lesions consisted of yellowish discoloration, swelling, edema, ...
Simulation studies of African horse sickness in Spain. Factors affecting epidemics of African horse sickness in Spain were studied using a mathematical model. The model examined the likelihood of an epidemic after the introduction of the virus, and the effectiveness of vaccination strategies. Two host species (horses and donkeys) and one vector species (the biting midge Culicoides imicola) were included. A stratified random sampling method (Latin hypercube sampling) was used for sensitivity analysis of the likelihood of an epidemic. Systematic variation of vaccination parameters was used to consider alternative control strategies. In general, when...
Local and systemic isotype-specific antibody responses to equine influenza virus infection versus conventional vaccination. Inactivated alum-adjuvanted conventional equine influenza virus vaccines are of poor efficacy and offer limited short-term protection against infection. In sharp contrast, natural infection with equine influenza virus confers long-term protective immunity. In order to identify the protective immune responses to equine influenza virus, the influenza virus-specific IgA, IgGa, IgGb, IgGc and IgG(T) antibody responses in nasal secretions and serum induced by natural infection and a commercial vaccine were studied by ELISA. Two groups of four influenza-naive ponies were established. In the natural ...
Association of deficiency in antibody response to vaccine and heterogeneity of Ehrlichia risticii strains with Potomac horse fever vaccine failure in horses. Ehrlichia risticii is the causative agent of Potomac horse fever (PHF), which continues to be an important disease of horses. Commercial inactivated whole-cell vaccines are regularly used for immunization of horses against the disease. However, PHF is occurring in large numbers of horses in spite of vaccination. In a limited study, 43 confirmed cases of PHF occurred between the 1994 and 1996 seasons; of these, 38 (89%) were in horses that had been vaccinated for the respective season, thereby clearly indicating vaccine failure. A field study of horses vaccinated with two PHF vaccines indicated...
Prospective study of equine colic risk factors. A 1 year prospective study was conducted on 31 horse farms to identify risk factors for equine colic. Farms were randomly selected from a list from 2 adjacent counties of Virginia and Maryland, USA. The association between colic and farm or individual horse risk factors related to management, housing, pasture, use, nutrition, health and events was first examined by univariate statistical analysis. Individually significant (P < = 0.25 for farm factors, P < = 0.10 for horse factors) variables were used in a stepwise multivariable forward logistic regression to select explanatory factors (P < = 0...
Intrinsic, management, and nutritional factors associated with equine motor neuron disease. To identify intrinsic, management, nutritional, and environmental risk factors associated with equine motor neuron disease (EMND) and to determine whether epidemiologic evidence supports oxidative stress as a risk factor for developing EMND. Methods: Case-control study. Methods: 87 horses with EMND and 259 control horses. Methods: Information concerning each horse's history of exposure to multiple environmental factors prior to developing EMND was obtained by means of a questionnaire or personal interview. Exposure histories of horses with EMND and control horses were compared, and the associa...
Cell-mediated cytolysis of equine herpesvirus-infected cells by leukocytes from young vaccinated horses. The objective of this study was to determine whether the administration of modified-live equine herpesvirus (EHV-1) to young horses with residual maternal antibodies stimulated EHV-specific cytolytic responses, and whether these responses were crossreactive between EHV-1 and EHV-4. Eighteen clinically normal Belgian cross-foals were used in the study and were commingled in two adjacent pens. Skin biopsies were harvested from 16 foals within 24 h of birth and fibroblast cultures were established, expanded and cryopreserved. Beginning at approximately 10 weeks of age, 10 randomly chosen foals we...
Equine arteritis virus. Equine arteritis virus (EAV) is a small, enveloped, positive-stranded RNA virus, in the family Arteriviridae , W.H.ich can infect both horses and donkeys. While the majority of EAV infections are asymptomatic, acutely infected animals may develop a wide range of clinical signs, including pyrexia, limb and ventral edema, depression, rhinitis, and conjunctivitis. The virus may cause abortion and has caused mortality in neonates. After natural EAV infection, most horses develop a solid, long-term immunity to the disease. Marzz and geldings eliminate the virus within 60 days, but 30 to 60% of acut...
Adverse reactions to veterinary drugs reported in Sweden during 1991-1995. The present article gives a summary of suspected adverse reactions reported by Swedish veterinarians during the period 1991-1995. The summary shows that severe adverse drug-reactions sometimes occur in Swedish veterinary practice. In horses, several cases of acute reactions in animals treated with procaine benzylpenicillin were reported and seven horses died within a few minutes after intramuscular injections of the drug. In cattle and swine most reports referred to the use of antimicrobial agents. In dogs reactions to vaccines were the most frequently reported adverse effects. The reactions w...
Patterns of health maintenance on Michigan equine operations. Data from two 12 month prospective monitoring programs that followed management, economics and animal health from randomly-sampled equine operations in Michigan were used to determine patterns of health maintenance. Health maintenance measures were grouped, and average uses per year were computed for the most-common measures reported: respiratory, Potomac Horse Fever, neurological and multiple-system vaccinations, deworming, and general farrier work. Factors examined for potential association with health maintenance measure use were numbers of equids and horse-days on the operation, average ag...
Use of a virulence-associated protein based enzyme-linked immunosorbent assay for Rhodococcus equi serology in horses. An enzyme-linked immunosorbent assay (ELISA) was developed against Rhodococcus equi using Triton X-114 detergent extracted whole cell material, in which the virulence associated protein (VapA) predominated. Enzymelinked immunosorbent assay titres corresponded to antibody reacting with VapA on Western blots. There was considerable variation in antibody titres of nonimmunised mares and in the time when the colostrally derived antibody of their foals had declined to low or undetectable titres. In general, antibodies in foals declined to their lowest levels at age 4-8 weeks. Seroconversion occurre...
Evaluation of vaccination of horses as a strategy to control equine monocytic ehrlichiosis. To determine whether preferentially vaccinated horses were at risk for exposure to Ehrlichia risticii, whether horses with equine monocytic ehrlichiosis (EME) were likely to have been nonvaccinated, and whether clinical severity and financial costs associated with care and treatment of EME were less for vaccinated horses with EME than for nonvaccinated horses with EME. Methods: Cross-sectional and case-control studies. Methods: Information on usage of E risticii bacterins to control EME was collected for 2,587 horses located on 511 farms throughout New York. Each horse was tested for serum ant...