A serological survey of the prevalence of Aujeszky's disease antibodies in Thailand using enzyme-linked immunosorbent assays (ELISA), serum neutralization (SN) and latexagglutination tests (LT).

The presence of Aujeszky's disease (AD) antibodies in eluates of whole blood on filter paper and corresponding sera from Thai pigs was determined by ELISA, SNT and LT. From a total of 800 samples tested by ELISA, 26% of the sera and 18% of the eluates showed positive results. From 640 samples tested by SNT and chosen because they gave negative, suspicious, or weakly positive results by ELISA, 22% were positive. A total of 182 suspicious samples were also tested by LT, and among them 63 (35%) were clearly positive. The investigation demonstrated that the older the animal, the greater the probability that antibodies would be found. Owner surveys tended to state that few animals had been vaccinated. This coupled with the high frequency of antibodies detected, indicates that AD-infection among Thailand's swine population is a common problem.

[Epizoologic studies of the detection of antibodies against Aujeszky's disease virus in sera and blood eluates of swine from Thailand using ELISA ("Enzygnost," Behring), serum neutralization test and "Aujeszky Latex Kit" (Iffa Merieux)]. / Epizootiologische Untersuchungen zum Nachweis von Antikörpern gegen das Virus der Aujeszkyschen Krankheit in Seren und Bluteluaten thailändischer Schweine mittels ELISA ("Enzygnost", Behring), Serum-Neutralisations-Test und "Aujeszky-Latex-Kit" (Iffa Merieux).

The results of three tests for Aujeszky's disease were analysed and compared. The presence of Aujeszky's antibodies was determined by "Enzyme-linked-Immunosorbent-Assays" (ELISA, "Enzygnost"), Behring company, Marburg; "Serum-Neutralization-Tests" (SNT); and "Latex Agglutination-Tests" (LT, "Aujeszky-Latex-Kit"), Iffa Merieux company, Laupheim. Whole blood and sera samples were taken from 805 swine from 26 of Thailand's provinces. These samples were analysed to determine if eluates of whole blood on filter paper were as effective as corresponding sera samples in determining the presence of Aujeszky's disease antibodies. From a total of 805 samples, 26% of the serum and 18% of the blood eluate samples showed a positive result when tested by the ELISA method. Clearly, testing whole blood eluates provides results which are inferior to results from sera samples. Therefore the ELISA whole blood eluates test can only be recommended with reservations. Further testing was done on 645 serum samples using SNT. Samples tested were those which gave negative, suspicious, or weakly positive results when tested by ELISA. Using SNT, 23% of these showed a positive result. Many serum and blood eluate samples were also tested by LT. Most of these test samples were chosen because they were deemed suspicious. Suspicious samples were defined as those which had deviant test results. According to these results the sensitivity of LT was between the sensitivity of SNT and ELISA. Owner survey responses tended to state that few animals had been vaccinated. This coupled with the frequency of antibody occurrence proves the high rate of infection among Thailand's swine population.