Evaluation of dengue blot test

Dengue blot test is a dot enzyme immuno-assay which detects the antibodies to dengue virus of all tyes (1 to 4). The result of the test can be obtained after three hours.In the management od dengue haemorrhagic fever confirmation of diagnosis should be made at early stage.This requires a test which is highly specific, highly sensitive and quick.To determine the usefulness of dengue blot test in diagnosing dengue haemorrhagic fever, this study was carried out in 319 patients who were clinically diagnosed as dengue haemorrhagic fever at Yangon Children Hospital.They were tested for both blot test and standard test of haemagglutination inhibition (HI).Blot test was positive in 304 patients out of which only one is negative for HI test (True positive 303 false positive 1).Out of 15 patients who were negative for blot test 10 were positive for HI test (True negative 5, false negative 10).This test was found to be highly sensitive (sensitivity 96

), and specific (specificity 83

).Positive predictive valve was 99.6

but negative predictive value was only 33.3

.

Histoplasma antibodies in subpopulations of Rangoon and Hmawbi (1971) 4,355-359

A survey for Histoplasma antibodies was carried out in June/July 1970 in random subsamples of both sexes of a rural group in Hmawbi Township and an urban group in Rangoon City respectively in the 1 to 45-yr age group. The subsamples numbered 76 and 74 respectively. Sera separated from whole blood were tested by slide agglutination. The antigen used was COLAB Histoplasmosis Latex Antigen; known positive anti-Histoplasma sera were used as controls. 44.6 per cent and 35.1 per cent gave positive reactions in the rural and urban groups respectively. The differences were not significant. 23.5 per cent of positives in the rural group and 34.6 per cent of positives in the urban group agglutinated at 1: 256. The difference was not significant. The highest number of positives occurred in the 11- to 20-yr age group in both areas, viz. 60.0 and 56.25 per cent respectively. The difference was not significant. 69.69 per cent of 33 males and 25..58 per cent of 43 females in the rural group and 43.33 per cent of 44 males and 29.34 per cent of 30 females in the urban group were positive. There was a significant difference between the numbers of positives in the males and females in the rural group.

Leptospiral antibodies in farmers at Myaung-dagar village in Hmawbi Township

A survey for leptospiral sero-antibodies was carried out in June 1969 in a random sub-sample of 122 adult farmers of both sexes of Myaungdagar Village in Hmawbi Township using a slide agglutination technique with Leptospira ballum, L. canicola, L. icterohaemorrhagiae, L. bataviae, L. grippotyphosa, L. pyrogenes, L. autumnalis, L. pomona, L. sejroe, L. australis, L. hyos and L. kremastos antigens. 69 (56.6 per cent) sera were positive for L. icterohaemorrhagiae, 53 (43.4 per cent) for L. ballum, 29 (23.7 per cent) for L. grippotyphosa, 10 (8.2 per cent) for L. pyrogenes, 10 (8.2 per cent) for L. pomona, 8 (6.6 per cent) for L. australis, 7 (5.74 per cent) for L. kremastos, 4 (3.3 per cent) for L. canicola, 2 (1.6 per cent) for L. autumnalis and I (0.82 per cent) for L. sejroe, 54 (91.5 per cent) of 59 L. icterohaemorrhagiae- positive sera, 24 (92.2 per cent) of 27 L. ballum-positive sera, 2 (13.3 per cent) out of 15 L. grippotyphosa-positive sera, 5 (60.0 per cent) out of 10 L. pomona-positive sera, 4 (57.1 per cent) out of 7 L. kremastos-positive sera and 4 (100.0 per cent) out of 4 L. canicola-positive sera agglutinated at titres of 1/512.