Studies on the carriage and transmission of porcine reproductive and respiratory syndrome virus by individual houseflies (Musca domestica).
The objectives of the study were to determine the site of porcine reproductive and respiratory syndrome virus (PRRSV) in individual houseflies, to assess whether an individual housefly could transmit PRRSV to a susceptible pig, and to compare the ability of PCR, virus isolation and a pig bioassay to detect PRRSV in houseflies. In the first experiment 26 houseflies were fed on a pig infected experimentally with PRRSV; 13 were processed as a whole fly homogenate, while an exterior surface wash and a gut homogenate were collected from the other 13. Infectious PRRSV was recovered from nine of the whole fly homogenates, 12 of the gut homogenates and one of the exterior surface washes. In the second experiment, two of 10 individual houseflies, which had fed on an infected pig, transmitted PRRSV to a susceptible pig in a controlled manual transmission protocol. In the third experiment, single flies or pools of 30 flies were immersed in different concentrations of a PRRSV inoculum, then tested by PCR, virus isolation and bioassay. The virus was detected at a concentration of 10(1) TCID50/ml by PCR, 10(2) TCID50/ml by the bioassay and 10(3) TCID50/ml by virus isolation.
Otake
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S
Swine Disease Eradication Center, University of Minnesota College of Veterinary Medicine, 385 Animal Science/ Veterinary Medicine Building, 1988 Fitch Avenue, St Paul, MN 55108, USA.
Dee
S A
SA
Moon
R D
RD
Rossow
K D
KD
Trincado
C
C
Pijoan
C
C
D000818:Animals; D001681:Biological Assay; D002353:Carrier State / Q000662:veterinary; D004279:DNA, Viral / Q000302:isolation & purification; D005247:Feeding Behavior; D006793:Houseflies / Q000821:virology*; D019318:Porcine Reproductive and Respiratory Syndrome / Q000635:transmission*; D019316:Porcine respiratory and reproductive syndrome virus / Q000302:isolation & purification / Q000472:pathogenicity*; D012680:Sensitivity and Specificity; D013552:Swine
D004279:DNA, Viral