Efficacy of a high potency O1 Manisa monovalent vaccine against heterologous challenge with a FMDV O Mya98 lineage virus in pigs 4 and 7 days post vaccination.
Early protection with a high potency (>6PD50) foot-and-mouth disease (FMD) O1 Manisa (Middle-East South Asia lineage) vaccine against challenge with O/VIT/2010 (O Mya98 lineage) was tested in pigs. Only two pigs that were vaccinated seven days prior to challenge had any demonstrable antibodies as a result of vaccination at the time of challenge. However, 80% and 60% of pigs that were vaccinated seven and four days prior to coronary band challenge were protected. Vaccination significantly reduced the amount of virus excreted in nasal swabs, saliva and faeces compared to unvaccinated and infected controls. Virus and viral RNA could be detected in some pigs until termination of the experiment 14 days after challenge. Antibodies to the non-structural proteins (NSP) were detected in only one pig that was challenged four days post vaccination (dpv) and transiently in two pigs that were challenged sevendpv at only one time point. For each vaccine and control group, a group of unvaccinated pigs were kept in the same room but with no direct contact with the infected pigs to determine whether vaccination prevented transmission. Despite the presence of live virus and viral RNA in these indirect contact pigs, the groups in contact with the vaccinated and infected pigs did not develop clinical signs nor did they sero-convert. Contact pigs in the same room as unvaccinated challenged controls did show signs of disease and virus infection that resulted in sero-conversion to the NSP. A breach of the wall that separated the two groups at nine days post challenge might have contributed to this finding. This study showed that high potency vaccine can provide protection to pigs soon after vaccination and that aerosol transmission within rooms is a rare event.
Australian Animal Health Laboratory, CSIRO-Biosecurity Flagship, Geelong, Australia. Electronic address: wilna.vosloo@csiro.au.
Vosloo
V
Wilna
National Veterinary Company, Ho Chi Minh City, Vietnam.
Nguyen Thi Thu
NT
Hong
Production Animal Studies, Faculty of Veterinary Science, University of Pretoria, Onderstepoort, Pretoria, South Africa.
Fosgate T
FT
Geoffrey
Australian Animal Health Laboratory, CSIRO-Biosecurity Flagship, Geelong, Australia.
Morris Michelle
MM
Jacqueline
Australian Animal Health Laboratory, CSIRO-Biosecurity Flagship, Geelong, Australia.
Wang
W
Jianning
National Veterinary Company, Ho Chi Minh City, Vietnam.
Kim
K
Van Phuc
National Veterinary Company, Ho Chi Minh City, Vietnam.
Quach Vo
QV
Ngon
National Veterinary Company, Ho Chi Minh City, Vietnam.
Le Thi Thu
le TT
Phuong
National Veterinary Company, Ho Chi Minh City, Vietnam.
Dang
D
Hung
National Veterinary Company, Ho Chi Minh City, Vietnam.
Tran Xuan
TX
Hanh
Center for Veterinary Diagnostics, Regional Animal Health Office 6, Ho Chi Minh City, Vietnam.
Vo
V
Van Hung
Center for Veterinary Diagnostics, Regional Animal Health Office 6, Ho Chi Minh City, Vietnam.
Le Thi Quynh
le TQ
Anh
Center for Veterinary Diagnostics, Regional Animal Health Office 6, Ho Chi Minh City, Vietnam.
Mai Thi My
MT
Tien
Center for Veterinary Diagnostics, Regional Animal Health Office 6, Ho Chi Minh City, Vietnam.
Le Tin Vinh
le TV
Quang
Center for Veterinary Diagnostics, Regional Animal Health Office 6, Ho Chi Minh City, Vietnam.
Ngo Thanh
NT
Long
Australian Animal Health Laboratory, CSIRO-Biosecurity Flagship, Geelong, Australia.
Singanallur Balasubramanian
SB
Nagendrakumar
D000818:Animals; D000914:Antibodies, Viral / Q000276:immunology; D005243:Feces / Q000821:virology; D005536:Foot-and-Mouth Disease / Q000517:prevention & control* / Q000635:transmission; D029544:Foot-and-Mouth Disease Virus / Q000235:genetics / Q000276:immunology* / Q000302:isolation & purification; D012367:RNA, Viral / Q000235:genetics / Q000302:isolation & purification; D012463:Saliva / Q000821:virology; D034421:Sus scrofa / Q000276:immunology*; D013552:Swine; D013553:Swine Diseases / Q000517:prevention & control* / Q000821:virology; D014611:Vaccination / Q000662:veterinary; D064166:Vaccine Potency; D014765:Viral Vaccines / Q000008:administration & dosage / Q000276:immunology*; D014766:Viremia / Q000821:virology
D000914:Antibodies, Viral; D012367:RNA, Viral; D014765:Viral Vaccines
Early protection; FMD vaccine; Heterologous challenge; High potency; Pigs