Althogh type-I hypersensitivity has been considered to play a major role in the aetiopathogensis of vernal conjunctivitis the exact role of tear and serum Immunohlonulin (IgE) in the diagnosis of disease is not certain. In an attempt to determine their role, tear and serum IgE estimations were done by Enzyme linked Immuno-assay (ELISA) in 54 patients of vernal conjunctivitis. Tear and serum IgE levels were significantly higher in patients as compared to controls. Five times more rise in tear IgE as compared to serum values, suggested local production of immunoglobulin E in the sub-conjunctival tissue in vernal conjunctivitis. Rise of tear IgE levels was more specific than serum IgE and showed positive correlation with the severity of symptoms.

Eight four (84) strains of Salmonella typhi were isolated from blood and stool culture of patients in S.S.K.M. Hospital, Calcutta. All the strains isolated showed multidrug resistance including chlormphenicol with MIC ranging from 100 mcg/ml to 1000 mcg/ml and they were also shown to carry R factors to multiple antibiotics like chlormphenicol, streptomycin, tetracycline, ampicillin and septran.

Two hundred and fifty eight sera of healthy adult blood donors, pregnant women and children in various age groups were tested for rubella antibody to determine their immune status using single radial haemolysis (SRH) test haemagglutination inhibition (HAI) test and enzyme linked immunosorbent assay (ELISA) test. The seroconversion was seen right from 0-5 years age group in which positivity of 22.73% was observed. The positivity increased with higher age groups and in the child bearing age group it reached 85%. All the sera tested positive by SRH test gave positive result by HAI and ELISA test also. However, the SRH and HAI test could not detect three and two immune sera respectively, out of 193 sera detected immune by ELISA test. SRH test was found to be efficient in detection of immune status to rubella. It was simple, economical and suitable for field application.

Inhibition enzyme - linked immunosorbent assay (ELISA) was standardised for the estimation of mycobacterial antigen in cerebrospinal fluid (CSF) specimens. Of the 40 patients with a clinical diagnosis of tuberculous meningitis (TBM) the assay was found to be positive in 28 patients. In a control group of 42 patients with non-tuberculous neurological diseases the assay was negative. The assay showed a sensitivity of 70% and 100% specificity for tuberculous aetiology. The inhibition ELISA, for the detection of mycobacterial antigen in CSF holds definite diagnostic potential for TBM because of its specificity. The assay could be applied as an aid in the laboratory diagnosis of TBM particularly when standard bacteriological methods are negative for M. tuberculosis in CSF specimens.

Serum IgG, IgM and IgA were estimated in intestinal amoebiasis (46 cases), extra intestinal amoebiasis (28 cases of hepatic amoebiasis) and giardiasis (36 cases). Controls comprised of 22 healthy individuals. In both types of amoebic infection serum IgG, IgM and IgA were significantly raised while in giardiasis depression of serum IgA was recorded, indirect Haemaggulatination method (IHA) for demonstration of specific antibodies against amoebiasis revealed that all control cases and those of giardiasis were negative, 52.17% cases of intestinal amoebiasis were positive as against 85.72% positivity observed in extra intestinal (hepatic, invasive) amoebiasis. Serum Igs were further correlated with IHA negative and positive cases. Serum lgG significantly higher in IHA positive cases of both extra- intestinal and intestinal amoebiasis. Serum IgM exhibited no relationship in either group while IgA showed significant alteration only intestinal amoebiasis.

Among the large number of helminthic parasites harboured by dogs Toxocars canis, Ancylostoma caninum, Echinococcus are particularly important because of their public health significance. An investigation was carried out on pet dog population in and around Chandigarh to assess the prevalence of Toxocara canis. Stool samples of 208 dogs were examined of which 9.6% were positive for T. canis. The occurrence was greater in puppies. The other parasite population found in the stool specimens included Ancylostoma caninum (26.5%) Taenia Echinococcus (10.3%) and Trichuris sps (1.48%).

Blood groups of 90 patients, 45 with peptic ulcers, 25 with non ulcer dyspepsia and 20 with other non G.T. Diseases, were compared for their relative susceptibility to duodenal colonization by yeasts mainly of genus Candida. There was a significant difference in yeast isolation among patient of different blood group, A significantly fewer patients of blood group A had infection and colonization of yeasts than predicated, and there was an increased number of patients, in non-A blood groups, especially group O, colonized by various yeasts. The commonest yeast isolated was Candida albicans from all blood group patients. Candida krusei was found to colonies only blood group AB patients. No yeast other than C. albicans and C. tropicalis was isolated from blood group A patients. Our results, thus, suggest than an individual’s blood group substance may be a significant factor in the host response to fungal infections by virtue of their cross reactivity with surface antigens on these fungal cells.

The taxonomic position of the strains of cholera vibrios isolated from epidemics in Calcutta and its surrounding areas during 1970-1980, with respect to the ‘classical’ and ‘E1 Tor’ vibrios, was examined on the basis of analysis of 42 different characters. It appeared that the ‘E1 Tor’ vibrios could be grouped into just two of the several biotypes of vibrio cholerae, which, again, was not the predominating type isolated in these epidemics.

Two hundred and ninety two veterinarians were screened for evidence of brucella infection by clinical, serological and bacteriological methods. 24 of them showed brucella antibodies in significant titers. 16 were symptomatic and remaining were asymptomatic. Six strains of Br. melitensis biotype I were isolated during the study.

Lancefield grouping of 85 clinical isolated of beta haemolytic streptococci isolated from sources other than throat has been carried out. Sixty one isolates (71.8%) belonged to group A, 14 (16.5%) to group B, 6(7.1%) to group G and 4 to group C. T-typing of all the 61 isolates of group A and typing of group B was further done. The Common patterns of group A were 5/11/12/27/44, 14, 3/13/B 3264, 4/28 and 8/25/ Imp. 19. Serotypes of group B streptococci obtained were I (1), Ib (2) and II (2).

One hundred and eighty six RF negative samples from patients with rheumatoid arthritis, rheumatic diseases other than RA and non-rheumatic diseases were tested by Latex agglutination inhibition test (LAIT) for the presence of hidden RFs. 76% of sero-negative RA group were positive for LAIT. In the other 2 groups the incidence of positive LAIT was 55.5% and 33.3% respectively. The sensitivity and specificity of LAIT to detect hidden RFs were found to be 75.8% and 84% respectively. The positive and negative predictive values of the test were 94.7% and 47.7% respectively.