Valeur des tests PACE et CTB_ELISA dans le diagnostic de la peste porcine classique (PPC) et le contr{ô}le de qualit{é} du vaccin correspondant {à} Madagascar

Abstract

From 1994, we began to use ELISA (Enzyme Linked Immunosorbent Assay) in the diagnosis of PCP. This is aELISA for capturing antigens (PACE) possibly contained in the samples. The advantage of this test comes from the fact that it is completelyindependent of cell cultures. In addition, it is fast: the result can be obtained in less than 36 hours. A study of its standardizationcarried out in Australia gave a sensitivity (Se) of 99%, a specificity (Sp) close to 100% and a negative predictive value (NPV) of 99.7%. Due to its high specificity, the test gives a negative result to all true negatives, in other words, the negatives of the test correspond to thetrue negatives. A variant of the capture ELISA, the CTB-ELISA or complex trapping blocking ELISA allows the quantity of antibodies to be measureddirected against the non-structural protein, p80 (or NS3), contained in animal sera. Evaluation of the level of anti-NS3 antibodiesconstitutes an excellent assessment of the level of neutralizing antibodies because the correlation coefficient between these two types of antibodies, the firstobtained by CTB-ELISA, and the second by serum neutralization (VNT), is very high (r = 0.98).The two tests being capable, one of detecting pestiviral antigens and the other of measuring antibodies specific to each of thegroups, constitutes an excellent tool for the qualitative control of anti-CSF vaccine.