Hepatitis B virus infection is a vaccine preventable infection of liver which remains a key public health burden globally. The development of Anti-HBs titre greater than or equal to 10 IU/L is considered as protective immunity and any titre less than 10 IU/L as non-protective following HBV vaccination. There is no comprehensive and authentic data regarding the immune response even 10 years after the integration of the HBV vaccine in to the EPI programme in Bangladesh and specifically, in Brahmonbaria district. The study was also aimed to assess the long term immune response among HBV vaccinated children. Blood sample from 500 vaccinated children were tested for Anti-HBs, and anti-HBc. Sero negative children were given 1 dose of HBV vaccine as a booster. Samples from booster vaccine were taken one month later and tested for anti Hbs titre. Anti HBs titre was found below protective level in about 46.0% (230/500) participants. Sero-protection rate decreased to 72.2% in 5 to 6 years age group which further decreased to 58.3% in 7 to 9 years age group and increased again to 69.5% in 10 to 12 years age group children. On the other hand, the mean anti Hbs titre was 97.72 IU/L initially and then increased with the increasing of age from 165.40 IU/L to 196.67 IU/L. Breakthrough infection of HBV was seen in 1.2% (6/500) participants measuring by anti HBc which indicated protective efficacy of HBV vaccine was about 98.8% (494/500). Sero negative participants were given a booster dose; 93.6% (131/140) participants showed boosting of mean anti HBs titre upto 804.92 IU/L which was below protective level (<10 IU/L) before booster dose. Anti-HBs titre goes below with the increase of age after vaccination. Most of the participants had immunological memory which will boost antibody titre after any exposure, so routine booster dose is not needed. But non-responder to vaccination should screen after primary vaccination because of chance of breakthrough infection.

AbstractsIn haemodialysis patients, hepatitis B virus infection has higher mortality and is more likely to result in the carrier state. Although Hepatitis B vaccine is effective in producing protection against HBV infection, the antibody response may be variable. In this study, seroprotection rate of hepatitis B vaccine in maintenance haemodialysis patients was studied after primary vaccination and after completion of the full vaccine regime. 50 unvaccinated patients on maintenance haemodialysis were included in this study. Patients negative for HBsAg, Anti-HBc (total) and Anti-HCV were vaccinated with 40µg of Engerix B following a schedule of 0, 1, and 2 months. The antibody titer was tested at 3 rd month and if the titer was <10 or between 10-100 mIU/ml, they were given another 4 th dose of vaccine at 6th month, and their antibody titer was tested again at 7 th month. In maintenance haemodialysis patients, the response rate to HBV vaccine was 44% after the primary vaccination and 80% after completion of the full vaccine regime.

Hepatitis B virus (HBV) infection is of global public health concern. Among various serological tests used for the diagnosis and screening of HBV infection, the enzyme-linked immunosorbent assay (ELISA) to detect hepatitis B surface antigen (HbsAg) is most widely used. The present study was designed to develop and standardize a cost effective in-house ELISA for the detection of HbsAg and compare its performance with two established commercial kits. The concentrations of coating antibody, conjugates and sera were fixed by checkerboard titration. Using known HBsAg positive and negative sera, four different concentrations (1, 0.5, 0.25 and 0.125 μg/well) of coating anti-HBs were applied. Similarly, serial dilutions of patients' sera (1 in 2, 1 in 3, 1 in 5 and 1 in 9) and conjugates (1 in 2, 1 in 3, 1 in 5, 1 in 9 and 1 in 17) were evaluated by checkerboard titration. The optimal concentration of coating antibody was determined at 0.25 μg/well and 1 in 9 dilution for both conjugates and sera. The performance comparison of our in-house ELISA showed excellent correlation with two commercial kits (Pearson 0.957, P=0.001 for monoclonal antibody coated kit and Pearson 0.929, P=0.000 for polyclonal antibody coated kit) when OD values were compared. All commercial kit proven positive samples was positive while all negative samples were negative with the in-house ELISA resulting in 100% sensitivity and specificity. The results of our study demonstrated that our inhouse ELISA for detection of HBsAg was equally as sensitive and specific as two well-known commercial kits. Thus, this system may be a useful tool for diagnostic and screening purposes, as well as outbreak investigations.

Rubella virus infection during pregnancy is an important cause of blindness, deafness, congenital heart disease, and mental retardation of the foetus. Multiple sero-surveys of rubella antibody among reproductive aged females of Bangladesh showed that 20-30% of them remain susceptible to rubella as rubella vaccination is yet not included in our national immunization program for adolescent and adult girls. The present study was designed to conduct a sero-survey among unmarried girls of 16 to 25 years to assess their serological status in terms of natural rubella infection and vaccinate the rubella susceptible individuals with a single dose of rubella vaccine to evaluate the immunogenicity of the vaccine. A total of 344 randomly selected unmarried, apparently healthy college students were enrolled and investigated for rubella IgG and IgM antibodies at the Department of Virology, Bangabandhu Sheikh Mujib Medical University (BSMMU), Dhaka. Girls who were found to be negative for both rubella IgG and IgM were vaccinated with a single dose of rubella vaccine and tested for rubella antibody after four to six weeks of vaccination. Quantitative analysis of rubella IgG showed that a total of 68.87% study population had protective rubella antibody, 29.36% were susceptible to rubella and 1.74% experienced recent rubella infection. After vaccination, rubella antibody positivity was found to be 100% among 99 (98.02%) of 101 vaccinated girls who were tested for anti rubella IgG. There was statistically significant increase (p <0.001, Paired t Test) in anti-Rubella IgG titres among pre-vaccination and post-vaccination sera. The findings of the study showed that it is mandatory to include young girls in the national immunization programme and immunize them with a single dose of rubella vaccine which was found to be 100% effective.

Human leukocyte antigen B27 (HLA-B27), a class I molecules of the major histocompatibility complex has a strong disease association with different types of spondarthropathies (SpA). The strength of this disease association varies markedly among racial and ethnic populations. The present study aimed to identify the HLA-B27 antigen frequencies among suspected SpA patients as well as healthy Bangladeshi individuals. The frequency of HLA-B27 was determined in 1500 patients and 1000 healthy subjects attending the Bangabandhu Sheikh Mujib Medical University (BSMMU). HLAB 27 typing was done by microlymphocytotoxicity test using commercial kit. A total of 738 (49.2%) suspected SpA patients and 107 (10.7%) healthy subjects tested positive for HLA-B27 antigen with higher frequency among younger age groups (54.9%, 52.4% and 56.2% in 0-14 years, 15-24 years and 25–34 years of age respectively). The male female positivity was almost same (11.4% and 9.6%) among control group, but in patient group it was 53.0% and 41.2% respectively. The findings of this hospital based study showed a high frequency of HLA-B27 among suspected SpA patients with male preponderance which is comparable with neighboring countries.Bangladesh Med Res Counc Bull 2014; 40 (3): 102-106