Enrollment of horses that demonstrated severe adverse vaccine reactions (reactors)
A group of 21 horses were accepted into the study for sample submission purposes. These samples were defined as a horse that had experienced a severe adverse reaction after vaccination either previously or during the course of the current study. A questionnaire was completed either by the owner or primary veterinarian (supplemental information). Clinical signs exhibited by these 21 horses included severe swelling at the injection site, fever, colic, laminitis, lethargy, and markedly stiff neck. Blood was collected and processed as previously described. Fourteen horses had blood drawn within 24 hours, two at 180 days, three at 270 days and two at unknown times after vaccination. Horses ranged from 2 to 15 years of age while age was not documented for 3 horses. There were 13 Warmbloods, 4 Quarter horses and 3 horses did not have their breed reported. Thirteen were geldings and 8 were mares.