Horse diseases-equine influenza, Biology

Equine influenza


Equine influenza is a highly contagious, epizootic disease, which affects equines of all age groups and is caused by influenza virus A/equine virus of family Orthomyxoviridae. The disease is characterized by sudden onset of cough and rapid spread of the disease. Influenza A/equine-1 (H7N7) or Influenza A/equine-2 (H3N8), RNA virus of family Orthomyxoviridae (RNA) are causative agents of this disease. Equine influenza virus A (EIV-A)/ equine 2 (H3N8) is the main strain causing the disease. Historically, EIV-A/ equine 1 has caused disease but for more than 20 years, it has not been reported. A major outbreak of equine influenza caused by Influenza A- Equi-2 virus (H3N8) was reported in India during 1987 and it re-emerged in 2008 after a gap of 21 years.


Epidemiology and transmission: The disease is transmitted by direct contact and inhalation of virus with infected materials. Fomite transfer, viz, veterinary clothing, equipment, vehicle from infected shed to healthy shed spread the disease. Aerosol spread occurs up to a distance of 35 meters. Housing of infected horses with healthy horses leads to rapid spread of this disease. Frequent coughing by infected horses produce infectious aerosols spreading the infection to healthy animals resulting in a highly explosive outbreak.


Clinical signs:
The disease starts with fever (38.5-410C, 101-1060C). The main symptom is dry and hacking cough in the beginning that become moist later. The temperature lasts for 1-3 weeks. Watery nasal discharge may be seen in the early stage.  Secondary bacterial complications are common, which lead to mucopurulent nasal discharge, persistent fever and abnormal lung sound.


Diagnosis: Diagnosis of EIV-A infection is based on virus isolation from nasal swabs, and/or by serology. Demonstration of seroconversion a  3- to 4- fold increase in haemagglutination inhibition (HI) antibody titre in paired serum samples collected on the day of onset of infection and then on 14-21 days provides confirmation of diagnosis. In single radial haemolysis test, two-fold increases in antibody titre in paired serum samples gives confirmatory diagnosis of EIV-A infection in horses. The EIV-A antigen can also be detected in nasal swab of infected horses by enzyme- linked immunosorbent   assay (ELISA) and by polymerase chain reaction (PCR).


Prevention and control:
There is no specific treatment. Affected animals should be given easily digestible food, housed in well-ventilated stalls and protected from cold wind. . Horses should be vaccinated with EIV-A killed vaccine. However, the immunity of the vaccine is of short duration. Hence, horses should be given booster immunization at interval of 4-6 months. At the onset of the disease, identify the infected horses and get the disease confirmed by laboratory testing. Segregate the infected horses. No new horse should be introduced in the stud farm during an outbreak and horses should also not to be allowed to leave until the outbreak is over.

Posted Date: 9/18/2012 7:54:43 AM | Location : United States







Related Discussions:- Horse diseases-equine influenza, Assignment Help, Ask Question on Horse diseases-equine influenza, Get Answer, Expert's Help, Horse diseases-equine influenza Discussions

Write discussion on Horse diseases-equine influenza
Your posts are moderated
Related Questions
Enumerate the major substrates for gluconeogenesis The major substrates for gluconeogenesis are the glucogenic amino acids, lactate  glycerol and (important  in ruminant) propi

help me in writing assignment on racemization,mutarotation.

Explain Food Applications of gum karaya The water absorbing and water-holding capacity of Karaya, together with an excellent acid compatibility made it suitable for its use

State about osteogenesis Embryologically, osteogenesis may be classified as either intramembranous or endochondral. When the ossification occurs directly, it is defined as intr

What is the vector of Chagas' disease? How is the disease transmitted? The vector of Chagas' disease is its middle host, a triatomine bug. The major species is Triatoma infesta

Future - Development Biology Fertilization in flowering plants is essential for sustaining life on earth. Production of most crops depends on the effectivity of the fertilisat

Define Regulation and Excretion of sodium and chloride? Renal excretion and retention of these elements is closely regulated. The total content of body sodium especially the co

Q. How different are the concepts of migration, emigration and immigration? The Migration is the moving of individuals of a species from one place to another. The Emigration is

In genetic recombination by crossing over what is the difference between parental gametes and recombinant gametes? The Parental gametes are those gametes that maintain the orig

Enumerate about the colour vision defects Acquired colour vision defects can occur afkr damage to the optic nerve or macula and in some cases, because of blue blindness in old