Parvovirus is a common agent of viral gastroenteritis. The morbidity and mortality rate is less than 20% and 5%, respectively. The most severe clinical type of disease is seen in young and growing animals (between 6 weeks and 6 months of age). The most important signs include: diarrhea, vomiting, anorexia and melena.

Canine distemper is one of the most important diseases in the carnivorous animals, with worldwide distribution. It is frequently seen in young dogs (3-6 months of age) without maternal immunity. The morbidity rate is about 25-75% and the mortality rate is about 50-90% depending on virus strain. The most important signs include: immune suppression, diarrhea, vomiting, coughing and diphasic fever.

In this survey 116 fecal and 152 conjunctiva samples were taken from the referred dogs to Small Animal Teaching Hospital, Faculty of Veterinary Medicine, University of Tehran from April 2007 to September 2008, with suspected clinical signs and unknown vaccination history. Antigen Rapid CPV & CDV antigen test kit of CPV and CDV were performed and then analyzed the major blood parameters of the dogs' concomitant with the test results. 88 and 96 positive out of 116 and 152 suspected cases of canine parvovirus and distemper, respectively.

The observed increased prevalence rate was probably due to the loss of immunity and lack of vaccination.