Seropositivity for intracellular bacterial infections among abattoir associated personnels.

Studies were carried out to detect the antibodies against zoonotic intracellular bacterial infections viz., brucellosis, listeriosis and tuberculosis in abattoir associated personnel employing dot-ELISA. Out of 165 serum samples tested 25.5, 40.0 and 10.9 per cent were detected as positive for brucellosis, listeriosis and tuberculosis, respectively. Immunodetection of these occupationally exposed persons for IgM as well as IgG antibodies revealed positivity for IgM, IgG and IgM + IgG in 8.5, 17.6 and 13.9 per cent for listeriosis and 5.5, 2.4 and 3.0 for tuberculosis respectively. Antibodies against brucellosis and listeriosis both were detected in 10.9 per cent persons, while 6.7 per cent persons were positive for both listeriosis and tuberculosis. No person was found positive with both brucellosis and tuberculosis. All the three infections were detected in 3.6 per cent persons.

Efficacy of indirect haemolysis test in the diagnosis of human brucellosis.

Indirect haemolysis test (IHLT) was used for the serodiagnosis of human brucellosis. Results were compared with those of STAT, RBPT, and CFT. Out of 77 sera 8(10.38 per cent), 15(19.48 per cent), 11(14.28 per cent) and 16(20.77 per cent) were found positive by RBPT, STAT, CFT and IHLT, respectively. Unlike in CFT, the prozone phenomenon was not observed in IHLT. IHLT may prove an effective alternative to use of CFT in the serodiagnosis of brucellosis.

Sero-prevalence of brucellosis among abattoir personnel of Delhi.

A total of 165 serum samples of abattoir personnel of Delhi were tested by Rose Bengal Plate test (RBPT), Standard tube agglutination test (STAT), Complement fixation test (CFT) and Dot-Enzyme linked immunosorbent assay (Dot-ElISA). The Seroprevalence was 20.60, 12.75, 50.30 and 25.45 percent, respectively on the basis of RBPT, STAT, CFT and Dot-ELISA. Seroprevalence was highest among blood collectors (99.77%) followed by miscellaneous group (72%), animal handlers (68.96%), butchers (68.00%) and sweepers (57.14%). Among veterinarians, Seroprevalance was 28.57%. The Seroprevalence was more among persons of higher age group. The study indicates that abattoir personnel are at high risk to infection with brucellosis.

Detection of IgM and IgG antibodies against Brucella by dot-ELISA in humans.

Dot-enzyme linked immunosorbent assay (dot-ELISA) with autoclaved extract of B. abortus S99 was used for the detection of Brucella antibodies in human sera. Results were compared with those of STAT, RBPT and CFT. Out of 80 sera 8(10 per cent), 15(18.7 per cent), 20(25 per cent) and 13(16.25 per cent) were found positive by RBPT, STAT, IgM dot-ELISA and IgG dot-ELISA respectively. Out of 74 sera samples tested with CFT 9(12.16 per cent) proved positive. The relative sensitivity and relative specificity in comparison with CFT was found to be 33.33 per cent, 96.92 percent for RBPT, 33.33 per cent and 84.61 per cent for STAT and 88.88 per cent and 76.92 per cent for dot-ELISA, respectively. The dot-ELISA was found to be a more sensitive, economical and a rapid test for screening of human brucellosis under field conditions.