Reintroduction of foot-and-mouth disease in Argentina: characterisation of the isolates and development of tools for the control and eradication of the disease.
This paper describes the antigenic and molecular characterisation of foot-and-mouth disease virus (FMDV) strains isolated during the 2000-2002 epidemic in Argentina, and the strategy implemented for disease control. Two different FMDV serotypes, O and A, were involved. Of the various field isolates studied, two distinct O1 lineages (strains Corrientes/00 and Misiones/00) and two serotype A lineages (A/Argentina/00 and A/Argentina/01 prototypes) were identified. The genome sequences of these strains were compared with sequences of previous regional isolates and sequences of vaccine strains. O1 strains were found to be related to regional strains while serotype A strains were found to be more distanced from them. The updating of the antigenic composition of the vaccines used in the emergency was a key issue, since the outbreaks stopped shortly after the implementation of the vaccination programs. The O1 strains quickly disappeared from the field following strict control measures and the use of vaccines containing O1/Campos strain. However, in the case of the A serotype strains, the situation was different, since the use of a vaccine containing strain A24/Cruzeiro yielded acceptable levels of protection only after re-vaccination. Therefore, the new field strains A/Argentina/00 and A/Argentina/01 were incorporated into the vaccine, leading to an effective control of the disease. Viral circulation greatly diminished, as indicated by the significant reduction in the number of outbreaks and in the number of animals with antibodies against non-structural proteins. Satisfactory levels of protective antibodies were subsequently detected in the cattle population (above 75% protection). The absence of outbreaks after January 2002 indicated that the epidemic was controlled.
Mattion
Nora
N
Centro de Virología Animal, (CEVAN-CONICET), Serrano 669 (1414), Buenos Aires, Argentina.
König
Guido
G
Seki
Cristina
C
Smitsaart
Eliana
E
Maradei
Eduardo
E
Robiolo
Blanca
B
Duffy
Sergio
S
León
Emilio
E
Piccone
María
M
Sadir
Ana
A
Bottini
Rodolfo
R
Cosentino
Bernardo
B
Falczuk
Abraham
A
Maresca
Ricardo
R
Periolo
Osvaldo
O
Bellinzoni
Rodolfo
R
Espinoza
Ana
A
Torre
José La
JL
Palma
Eduardo L
EL
D000818:Animals; D000911:Antibodies, Monoclonal / Q000032:analysis; D000956:Antigens, Viral / Q000032:analysis / Q000276:immunology; D001118:Argentina / Q000453:epidemiology; D002417:Cattle; D002418:Cattle Diseases / Q000453:epidemiology* / Q000517:prevention & control / Q000821:virology; D002626:Chemistry, Pharmaceutical; D003140:Communicable Disease Control / Q000379:methods*; D018076:DNA, Complementary / Q000737:chemistry / Q000235:genetics; D004196:Disease Outbreaks; D004306:Dose-Response Relationship, Immunologic; D004797:Enzyme-Linked Immunosorbent Assay; D005536:Foot-and-Mouth Disease / Q000453:epidemiology* / Q000517:prevention & control / Q000821:virology; D029544:Foot-and-Mouth Disease Virus / Q000235:genetics / Q000276:immunology*; D007114:Immunization; D009500:Neutralization Tests; D012367:RNA, Viral / Q000737:chemistry / Q000235:genetics; D014764:Viral Proteins / Q000097:blood; D014765:Viral Vaccines / Q000627:therapeutic use
D000911:Antibodies, Monoclonal; D000956:Antigens, Viral; D018076:DNA, Complementary; D012367:RNA, Viral; D014764:Viral Proteins; D014765:Viral Vaccines