Some guidelines for determining foot-and-mouth disease vaccine strain matching by serology.
The selection of matching strains for use in outbreaks of foot-and-mouth disease (FMD) virus can be assessed in vivo or by serological r-value determination. Sera from animals involved in vaccine potency and cross-protection trials performed using the "Protection against Podal Generalization" (PPG) test for two serotype A strains were collected and analyzed by the virus neutralization test (VNT) and liquid-phase ELISA (lpELISA) in three laboratories. The average VNT r-values for medium and high serum titer classes from the A(24) Cruzeiro vaccinated animals were in line with the A/Arg/01 heterologous PPG outcome for all testing laboratories, suggesting that the vaccine strain A(24) Cruzeiro is unlikely to protect against the field isolate A/Arg/01. The corresponding lpELISA r-values were slightly higher and indicate a closer relationship between both strains. Pooling of serum samples significantly reduced the inter-animal and inter-trial variation. The results suggest that a suitable reference serum for vaccine matching r-value experiments might be a pool or a medium to high VNT or lpELISA titer serum. Furthermore, the VNT seems to produce the most reproducible inter-laboratory results. More work is, however, needed in order to substantiate these claims.
Mattion
Nora
N
Centro de Virología Animal, Instituto de Ciencia y Tecnología Dr. César Milstein, CONICET, Saladillo 2468, Buenos Aires, Argentina. nmattioncevan@centromilstein.org.ar
Goris
Nesya
N
Willems
Tom
T
Robiolo
Blanca
B
Maradei
Eduardo
E
Beascoechea
Claudia Perez
CP
Perez
Alejandro
A
Smitsaart
Eliana
E
Fondevila
Norberto
N
Palma
Eduardo
E
De Clercq
Kris
K
La Torre
José
J
D000818:Animals; D000914:Antibodies, Viral / Q000097:blood / Q000276:immunology; D001118:Argentina / Q000453:epidemiology; D002417:Cattle; D003429:Cross Reactions; D004196:Disease Outbreaks; D004797:Enzyme-Linked Immunosorbent Assay; D005536:Foot-and-Mouth Disease / Q000453:epidemiology / Q000517:prevention & control* / Q000821:virology*; D029544:Foot-and-Mouth Disease Virus / Q000145:classification* / Q000276:immunology*; D007118:Immunoassay / Q000592:standards; D009500:Neutralization Tests; D014765:Viral Vaccines / Q000276:immunology*
D000914:Antibodies, Viral; D014765:Viral Vaccines