Transmission pattern of parainfluenza 3 virus in guinea pig breeding herds
Blomqvist, G.A.M.; Martin, K.; Morein, B.
Contemporary Topics in Laboratory Animal Science 41(4): 53-57
2002
ISSN/ISBN: 1060-0558 PMID: 12109899 Document Number: 548123
In search for the cause of experimental variations in respiratory research data, serology revealed the prevalence of antibodies against parainfluenza virus type 3 (PIV 3) in guineapigs. The aim of the present study was to explore the transmission rate, course, and kinetics of enzootic PIV 3 infection in guineapig breeding units. In the first part of the study, blood samples to be analysed for PIV 3 antibodies were collected from guineapigs of a PIV 3-positive breeding colony at different times after birth. In the same breeding unit, 6 of 12 two-week-old guineapigs were relocated and separately housed. The PIV 3 serum antibody titres of the 2 groups were compared at various times from birth to 13 weeks after birth. In the second part of the study, the spread of infectious virus and virus persistence were explored by housing seronegative sentinel animals together with 2- to 3-week-old guineapigs from 3 different PIV 3-positive breeding units. The guineapigs remaining in the breeding colony as well as those removed and housed separately showed declining serum antibody titres for about one month after birth, thereafter the titres were stable until about 8 weeks after birth. Five weeks later, the mean antibody titre of the guineapigs remaining in the breeding colony had increased to a markedly higher level than that of the relocated, separately housed guineapigs. Seroconversion was demonstrated in 7 of the 14 sentinels housed with the 2- to 3-week-old guineapigs from PIV 3-positive breeding units. Sentinels housed together with PIV 3-positive guineapigs 24 weeks after the start of the experiment did not seroconvert. It is concluded that young guineapigs born to PIV 3-positive mothers are protected by maternal immunity against infection with PIV 3 during their first 14 days of life. The guineapig offspring became infected during the period from about 2 weeks until 8 weeks after birth, as demonstrated by seroconversion of sentinel animals and an increasing mean antibody titre seen beyond 8 weeks of age. The study did not reveal any indication of virus persistence or prolonged carrier status.