Seroepidemiological investigations on human immunodeficiency virus infections in some parts of India.

PIP: 2597 serum samples from individuals belonging to various groups were screened for antibodies to human immunodeficiency virus (HIV). The majority of the sera screened were from residents of India; 16 were from foreigners. Screening was done using ELISA kits from 4 different commercial sources. Samples which were reactive initially were retested using the same kit. 4 samples were reactive repeatedly in all the kits used. 2 of these were from patients with Acquired Immune Deficiency Syndrome (AIDS), 1 from a patient with AIDS-related complex, and 1 from an apparently healthy female prostitute living in Bombay. These 4 samples were confirmed to be positive by Western Blot, immunofluorescence, and the Karpas AIDS test. Among the sexually promiscuous persons screened for antibodies to HIV in India, female prostitutes appear to be the only risk group in whom antibodies to HIV virus have been detected. This also has been reported from Tamil Nadu. Positive reactors among blood donors screened even in areas of high incidence of AIDS has been very low. There were no positive reactors among the tribals, naval personnel, and individuals from jails. Overall, the data and an earlier report from Delhi suggest that the activity of AIDS retrovirus remains low in India, but the possible threat of spread of this disease should be considered. As prostitutes have been the only risk group with positive serological evidence of HIV infection, surveillance of this group is indicated.^ieng

Persistence of antibodies induced by measles-mumps-rubella vaccine in children in India.

Antibody levels in 41 Indian girls were measured 6 years after measles-mumps-rubella (MMR) vaccination. Rates of seropositivity were 88% (measles antibodies), 95% (mumps antibodies), and 100% (rubella antibodies). The MMR vaccine induces long-term immunity in a majority of vaccinees; however, due to the observation of some seronegative vaccinees, the policy of administering a second dose of the MMR vaccine seems appropriate.

Immunogenicity of a new, low-cost recombinant hepatitis B vaccine derived from Hansenula polymorpha in adults.

BACKGROUND: Hepatitis B virus (HBV) infection is highly prevalent world over, especially in developing countries. A new recombinant hepatitis B virus (GeneVac-B; Serum Institute of India Ltd.) vaccine is developed using Hansenula polymorpha yeast. We decided to assess the immunogenicity, and reactogenicity of this vaccine in a large adult population. MATERIAL AND METHODS: Seven hundred eighty-eight adults subjects (age: 19-57 years, male:female ratio 35:1) received three 20 microg doses of a H. polymorpha-derived recombinant hepatitis B vaccine in months 0, 1, and 6. All the eligible subjects had negative baseline serum HBs Ag, and anti-HBs. The anti-HBs titer was obtained 1 month after the last dose of vaccine and was considered seroconverted if more than 1 mIU/ml, and seroprotective if more than 10 mIU/ml. RESULTS: The seroprotection rate was 96% and seroconversion rate was 97%. Seroconversion and seroprotection rates declined with increasing age. The minimum geometric mean titre of anti HBs was 443 mIU/ml (95% CI 407-482). Seroprotection was 96% in age group<40 years, while the same was 91% in >40 years group (Odd's ratio-2.9100, Z value-2.6183, highly significant). No other factor like smoking, tobacco-chewing, alcohol consumption, chronic diseases, and obesity, affected the immune response. No significant adverse reactions were reported in any of the subjects. CONCLUSIONS: Three standard doses of the H. polymorpha-derived recombinant HBV vaccine are highly immunogenic and safe in a predominantly male adult population. Young adults respond better with this vaccine. Because of its low cost, the vaccine may be a good choice in prevention of hepatitis B infection.

Horizontal transmission of hepatitis B virus infection in household contacts, Pune, India.

The study was undertaken to detect the risk of infection, if any, among 193 household contacts of 40 hospitalised hepatitis patients (group I) with hepatitis B surface antigen (HBsAg) in their blood. As a control group, 103 household contacts of 27 hospitalised hepatitis patients who were negative for HBsAg (group II) were investigated. The family contacts of the former group had a significantly higher prevalence of HBV infection than those of the latter group (P less than .001). Significant differences were observed both in the prevalence of HBsAg (P less than .05) and antibody to HBsAg (anti-HBs) (P less than .025) between the two groups. IgM antibody to hepatitis B core antigen (anti-Hbc-IgM) was detected in 32 out of the 39 (82%) sera tested from the patients of group I with HBsAg. A statistically significant difference (P less than .005) of HBV prevalence was also found in the contacts of these 32 patients suffering from acute hepatitis B as compared to the contacts of the patients of group II. Overall, the children of the first group showed a significantly higher prevalence of HBsAg as compared to the second group. All the children with HBsAg were positive for HBeAg also, but were negative for anti-HBc-IgM. Anti-HBs was detected in a significantly larger number of adult females. Spouses were found to be affected more than other relatives. A significant difference (P less than .025) was noted in the number of families having HBV markers in group I (80.0%) as compared to those in group II (48.1%).(ABSTRACT TRUNCATED AT 250 WORDS)