Equine rhinitis A virus (ERAV and ERBV) are respiratory pathogens of horses that infect the nasal cavities and accompany other respiratory infections such as equine influenza.
Age as factor in horse respiratory infections
A horse afflicted with equine rhinitis virus usually exhibits nasal discharge that starts watery and gradually becomes thicker and yellow in color.
A horse afflicted with equine rhinitis virus usually exhibits nasal discharge that starts watery and gradually becomes thicker and yellow in color. Horses may also sneeze, sniffle, cough and have eye discharge and fever. Sub-clinical signs include coughing, anorexia, pharyngitis, laryngitis and enlarged submandibular lymph nodes.
In research conducted by Boehringer Ingelheim Vetemedica with veterinarians at several leading universities, it was determined that seroprevalence for exposure to ERAV appeared to increase with age. In a study of 1021 horses evaluating serum samples, 44 percent or 451 horses had neutralizing antibodies to ERAV, while 15 percent or 164 horses were positive to ERBV.
Of the horses evaluated, specific ages were available for 554 horses and seroprevalence for exposure to ERAV appeared to increase with age:
Yearlings (11 of 126) 9%
2-year-olds (44 of 116) 38%
3-year-olds (50 of 163) 31%
4-year-olds (52 of 149) 35%
The report stated that “Serum neutralization antibodies to ERAV appear to be more common than ERBV in the population studied. ERAV and ERBV infections warrant further investigation in horse populations in the United States and determination of their relationship to other concurrent respiratory pathogens in horses.”
The results of the study were recently presented to the American College of Veterinary Internal Medicine Forum in New Orleans, Louisiana by veterinarian Rob Keene, the company's equine technical manager.
“Over the past decade, serologic evidence of infection has been documented in Canada, Australia and throughout Europe. However, little recent serologic data exists in horse populations in the United States.”
The study’s aim was to determine the prevalence of Equine Rhinitis Virus A and B in the serum of horses between the ages of 1 and 4 by measuring serum-neutralizing antibodies in diverse geographic regions of the US.
Frozen serum samples were obtained from six veterinary laboratories, and the samples were shipped to Cornell Animal Health Diagnostic Center for evaluation.
The Boehringer Ingelheim group is one of the world’s 20 leading pharmaceutical companies. The group, based in Germany, has more than 42,000 employees.