Efficacy of Fostera® PRRS modified live virus (MLV) vaccination strategy against a Thai highly pathogenic porcine reproductive and respiratory syndrome virus (HP-PRRSV) infection.
Recently, the Chinese highly pathogenic porcine reproductive and respiratory syndrome virus (PRRSV) (HP-PRRSV) belonging to lineage 8 causes severe symptom with high morbidity and high mortality rates to the Asian pig industry. A recent study showed that pigs immunized with Fostera® PRRS modified live virus (MLV) of lineage 8 could provide a degree of protection against a Vietnamese HP-PRRSV infection. It should be noted that PRRSV commonly found after weaning causes porcine respiratory disease complex (PRDC). Vaccination strategy should be evaluated in each farm scenario. Eighty-one PRRSV-free piglets obtained from a PRRS-free herd were divided into two experiments with the major difference of infection timing after vaccination, 42 days in experiment 1 (n = 42) and 28 days in experiment 2 (n = 39). Each experiment had similar protocol containing three groups including a negative control, unvaccinated challenged, and vaccinated challenged groups. Pigs in vaccination groups were immunized with Fostera® PRRS MLV vaccine at 3 weeks of age. Then, unvaccinated challenged and vaccinated challenged groups were intranasally inoculated with a Thai HP-PRRSV (10PL01). Vaccinated challenged pigs showed significantly lower levels of mean rectal temperatures, clinical severity, lung lesion scores, and viral titers in serum and lung tissue compared to the unvaccinated challenged pigs (p < 0.05). Vaccinated challenged pigs had higher survival rate than those of unvaccinated challenged pigs in both experiments. It should be noted that pigs challenged 42 days after vaccination showed a better performance than pigs challenged 28 days after vaccination. In conclusion, Fostera® PRRS MLV vaccine was able to improve the survival rate against the Thai HP-PRRSV infection in both 42- and 28-day vaccination-to-infection protocols.
Department of Pathology, Faculty of Veterinary Science, Chulalongkorn University, Bangkok, 10330, Thailand.
Ponlakrit
P
Charoenchanikran
Department of Pathology, Faculty of Veterinary Science, Chulalongkorn University, Bangkok, 10330, Thailand.
Roongtham
R
Kedkovid
Department of Pathology, Faculty of Veterinary Science, Chulalongkorn University, Bangkok, 10330, Thailand.
Chaitawat
C
Sirisereewan
Department of Pathology, Faculty of Veterinary Science, Chulalongkorn University, Bangkok, 10330, Thailand.
Yonlayong
Y
Woonwong
Department of Pathology, Faculty of Veterinary Science, Chulalongkorn University, Bangkok, 10330, Thailand.
Jirapat
J
Arunorat
Department of Pathology, Faculty of Veterinary Science, Chulalongkorn University, Bangkok, 10330, Thailand.
Panchan
P
Sitthichareonchai
Department of Pathology, Faculty of Veterinary Science, Chulalongkorn University, Bangkok, 10330, Thailand.
Natthawan
N
Sopipan
Department of Pathobiology, Faculty of Veterinary Medicine, Khonkhaen University, Bangkok, 40002, Thailand.
Suphattra
S
Jittimanee
Department of Pathology, Faculty of Veterinary Science, Chulalongkorn University, Bangkok, 10330, Thailand. sawang.k@chula.ac.th.
Sawang
S
Kesdangsakonwut
Department of Pathology, Faculty of Veterinary Science, Chulalongkorn University, Bangkok, 10330, Thailand. roongroje.t@chula.ac.th.|Center of Emerging and Re-emerging Infectious Diseases in Animals, Faculty of Veterinary Science, Chulalongkorn University, Henri-Dunant Rd., Bangkok, 10330, Thailand. roongroje.t@chula.ac.th.
Roongroje
R
Thanawongnuwech
D000818:Animals; D000831:Animals, Newborn; D000914:Antibodies, Viral / Q000097:blood; D008297:Male; D019318:Porcine Reproductive and Respiratory Syndrome / Q000401:mortality / Q000517:prevention & control*; D019316:Porcine respiratory and reproductive syndrome virus / Q000276:immunology* / Q000472:pathogenicity; D016019:Survival Analysis; D013552:Swine; D013785:Thailand; D014329:Tropical Climate; D014611:Vaccination / Q000662:veterinary*; D014613:Vaccines, Attenuated / Q000276:immunology; D014765:Viral Vaccines / Q000276:immunology*
D000914:Antibodies, Viral; D014613:Vaccines, Attenuated; D014765:Viral Vaccines
Efficacy; HP-PRRSV; Lineage 8; MLV; Vaccine