Brucellosis 2003 proceedings - PHIDIAS

Poster Session
53- ELISA AS AN ALTERNATIVE METHOD FOR THE DIAGNOSIS OF
BRUCELLOSIS IN SHEEP.
Jalali, A. 1 , Hemmatzadeh, F. 2 , Momtaz, H. 2 and Nilsson, E. 1 . (1) Svanova Biotech AB, Sweden. (2)
Faculty of Veterinary Medicine, Tehran University, Iran.
Brucellosis is an important zoonotic disease caused by the bacterium Brucella,
affecting various animal species. Although many countries have succeeded to control
this disease in cattle, brucellosis in small ruminants has been less favourable.
However, due to the economical and health impacts of this issue, there is a need for
easily standardized and performed tests for this purpose.
Two antibody ELISA’s (SVANOVIR), one indirect and one competitive were
evaluated on sheep sera. In the first stage 150 negative (Sweden) and 120 positive
(Iran and Israel) samples were tested on both assays. The samples were
characterized by serology and/or cultivation. The results were as follows:
Assay Sensitivity Specificity Cut off
Indirect ELISA 94,3 100 PP >= 15
Competitive ELISA 100 100 PI >= 30
To confirm validity of the chosen cut off, the trial was repeated on 1094 sheep
samples from herds in Iran. All samples were tested with Rose Bengal (RBT), Wright
and 2-ME according to standard procedures. Out of the 1094 sheep samples, 83 %
were negative in all three conventional assays. Out of these only 5 % was positive in
the C-ELISA whereas 41 % in the I-ELISA. Out of the 14 % tested positive in all three
agglutination tests, 97 % was positive with the I-ELISA and 69% with the C-ELISA.
Two percent of the total material showed discrepancies in the agglutination tests.
However, in this group the specificity of the C-ELISA against 2-ME was 82%. The
study shows that the ELISA tests could be suitable replacements for the conventional
tests for screening as well as for confirmatory applications.
54- EVALUATION OF THE ELISA IN DIAGNOSIS OF BRUCELLOSIS IN PIGS.
K. Szulowski, W. Iwaniak, J. Pilaszek. Department of Microbiology, National Veterinary Research
Institute in Pulawy, Poland.
According to Manual of Standards for Diagnostic Tests and Vaccines the
serological methods recommended in diagnosis of brucellosis in pigs are ELISA,
BBAT and FPA. The aim of the studies was to evaluate the properties of the indirect
ELISA (I-ELISA) used in diagnosis of swine brucellosis in Poland. In the test the
microplates coated with the “smooth” lipopolysaccharide (S-LPS) obtained from the
strain S19 of Brucella abortus, the conjugate of anti-swine immunoglobulins with
horseradish peroxidase and ABTS with H 2 O 2 as the substrate, were used. The
controls of the ELISA kit consisted of: strong positive swine serum (S++), weak
positive serum (S+) and negative serum (S-) prepared respectively on the base of
sera from pigs coming from Brucella infected herds and pigs free of brucellosis. In
the examination 105 sera from pigs from 3 infected herds, 92895 sera from healthy
pigs monitored for brucellosis from territory of Poland and 3662 sera from imported
pigs were used. Besides ELISA the traditional methods such as RBT, CFT and
additionally for some samples, SAT and 2-ME were used. Of pigs from infected herds
102 sera reacted positively in the ELISA, whereas 95 sera were positive in the RBT
and 98 in the CFT. In the screening surveys only 11 positive results were obtained in
Brucellosis 2003 International Research Conference
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