Immune response to hepatitis B vaccine in haemodialysis patients.

Widespread vaccination of haemodialysis patients had occurred during the year 1999 as a result of the promulgation of the Ministry of Health & Population. To our knowledge, this might be the first study in Egypt concerning post-vaccination response in haemodialysis patients and possible risk factors influencing this response. Eighty-three haemodialysis patients vaccinated with 10 microg dose of recombinant hepatitis B Merck Sharp vaccine at 0, 1 and 6 months were enrolled in the study. Blood samples were withdrawn one month after the third dose and sera were tested for anti-HBc to exclude those who had previous HBV exposure and for quantitative determination of antibodies to hepatitis B surface antigen (anti-HBs) using commercial enzyme immunoassay kits. Routine analysis for anti-HIV, anti-HCV and HBsAg every 3 months is done for all haemodialysis patients in the governmental sector. Only 65 patients negative for both anti-HBc and HBsAg were considered eligible for evaluating the immunogenicity of the vaccine. Seroconversion rate (anti-HBs>10 mlU/ml) was detected in 64.6% and adequate response (anti-HBs>100 mlU/ml) was achieved in 38% only. Non-responders were 35.4% reflecting the profound immune suppression in haemodialysis patients. Seroconversion rate was 84.2% in patients below 40 years of age and dropped to 33.3% in those 60 years or above. Seroconversion was significantly higher in females than males (76.5% vs. 51.6%). HCV infection was strikingly high among dialyzed patients (78.5%). Seroconversion rate was 58.8% in HCV-infected and 85.7% in non HCV-infected haemodialysis patients. Neither the duration of haemodialysis nor the frequency of blood transfusions had any significant association with seroconversion rate.

Seroprevalence of Helicobacter pylori among Egyptian newborns and their mothers: a preliminary report.

Helicobacter pylori is one of the most common human bacterial infections in the world and children in the developing countries acquire H. pylori infection early in life. We prospectively evaluated the prevalence of serum antibodies to H. pylori in a cohort of pregnant women and their offspring. Mothers' sera were collected during the third trimester of pregnancy and sera from their offspring were collected when they were 7-9 months and 18 months of age. Pylori-Stat, a commercially available ELISA kit, was used to detect antibodies to H. pylori in the serum of the subjects tested. Sera from 169 mothers were available for testing and 88% of these samples were positive for anti-H. pylori IgG. Of the 169 children tested, 13% of the infants 7-9 months of age and 25% of the children 18 months of age had serologic evidence of H. pylori infection. These data indicate that infection with H. pylori is common in Egypt and acquisition of infection occurs at a very young age.

Health status assessment of drug addicts in Alexandria.

The case-control study was conducted among addicts in Alexandria to determine the different health problems among them, as well as to study the correlation between addiction and these problems. One hundred drug addicts and eighty apparently healthy controls were included in this study. The whole sample was subjected to the following: filling a predesigned questionnaire sheet, clinical and electrocardiogram (ECG) examination, measurements of Body Mass Index (BMI), complete blood picture and antistreptolysin O titre (ASO), testing for hepatitis B surface antigen (HBsAg) and antibody to hepatitis B core antigen (anti HBc), skin scrapings from superficial fungal lesions in addition to complete urine and stool examination. The results revealed that chest rhonchi, hepatomegaly, central nervous system (CNS) abnormalities, skin lesions lymphadenopathy, underweight and anaemia were significantly higher among addicts than the controls. Hepatitis B virus (HBV) exposure and HBsAg seropositivity were found 48.0% and 21.0%, respectively among addicts compared to 26.3% and 5.0%, respectively among the controls. The intravenous injections and tattooing were the most risky routes for HBV infection among addicts. A positive correlation was revealed between HBV exposure and both the duration and the number of daily injections. Chest X-ray suggestive of pulmonary tuberculosis were found in 7.0% of the addicts. Addiction potentiated the risk of fungal infection among low social class, but it had no effect on the relationship between anaemia and social class nor on that between loss of appetite and underweight.

Immunogenicity of recombinant hepatitis B vaccine among infants of mothers with active schistosomiasis.

A study of the immunogenicity of a recombinant hepatitis B vaccine was conducted among 385 Egyptian infants, 191 (49.6%) of whom were born to mothers with moderately active Schistosoma mansoni infection (mean egg count = 224 eggs/g of feces). All mothers were seronegative for hepatitis B surface antigen (HBsAg) and hepatitis B e antigen. Infants were vaccinated with a 2.5-microg dose of this vaccine, given along with diphtheria, tetanus, and pertussis (DTP) vaccine, at the ages of two, four, and six months. Serum samples taken from each infant at nine months of age were tested for HBsAg, antibody to hepatitis B core antigen, and quantitatively for antibody to hepatitis B surface antigen (anti-HBs). There was no significant difference (P = 0.1) between anti-HBs titers in infants of S. mansoni-infected mothers (mean = 539 mIU/ml) and in infants of noninfected mothers (mean = 377 mIU/ml). This study shows that there was no apparent effect of maternal schistosomiasis infection on the immune response of these infants to vaccination.

Comparative study of the immunogenicity and safety of two dosing schedules of hepatitis B vaccine in neonates.

Healthy Egyptian neonates born to hepatitis B surface antigen (HBsAg)-seronegative mothers were randomly enrolled in one of three vaccination schedules. A dose of 2.5 micrograms of recombinant HB vaccine was given at birth, two, and six months of age (group A) or two, four, and nine months of age (group B). These two groups and a third control group (group C) also were given the other routine childhood vaccines (BCG, DPT, polio, and measles). Blood samples were taken one month after the third vaccine dose in groups A (seven months of age) and B (10 months of age), and a second follow-up blood sample was taken at the age of 18 months for all three groups. Sera were tested for HBsAg and antibody to hepatitis B core antigen, and quantitatively for antibody to hepatitis B surface antigen (anti-HBs) using commercial enzyme immunoassay kits. The vaccine was well tolerated and side effects were limited to local soreness, redness, or temporary swelling. Among 590 infants who were followed-up, good (51-300 mIU anti-HBs/ml) or excellent (> 300 mIU/ml) immune responses occurred in 85% of the infants in group A and in 96% in group B. Geometric mean titers of anti-HBs at the first and second follow-up were 306 and 55 mIU/ml in group A, and 1,492 and 147 mIU/ml in group B. The recombinant HB vaccine is safe and immunogenic when given in three doses of 2.5 micrograms in either regimen, but delay of the booster dose of the vaccine until nine months after birth produced a higher immune response.

Hepatitis B surface antigen in Cimex lectularius.

Bedbug (Cimex lectularius) samples adult and nymphs either engorged or starved from Central Security Forces sleeping wards, laboratory animal house and control samples from laboratory reared colonies were ground and subjected to ELISA test of hepatitis B surface antigen together with 276 serum samples from the recruits slept in those wards. In the camp 7 out of 30 samples of engorged adult bedbugs were positive to HBSAg and 5 out of 30 samples of starved bedbugs were positive. Regarding nymphs 4 out of 30 engorged samples showed positive results. One of five samples of engorged adult bedbugs from the laboratory animal farm was positive. The control samples were negative. Serum samples of 276 recruits showed 3.6% positive results of HBSAg.

Vertical transmission of HBsAg in Alexandria.

A total of 735 pregnant women at delivery and their babies were screened for HBsAg to assess the vertical transmission of HB virus infection. The carrier rate among pregnant women was 5%, evidence of intrauterine transmission reached 8.1% and that of perinatal transmission was 33.3% The most important factors affecting the carrier rate in mothers were the social class, parity, injections, dental manipulation and hospitalization. Nevertheless, among the factors increasing the rate of materno-fetal transmission were the presence of "e" Ag, high titer of HBsAg in mothers serum, cord blood antigenaemia, age of the mother, prolonged duration of labour and breast-feeding.

Study of the sensitivity of blood spotted on filter paper in the detection of HBsAg and anticore using ELISA technique.

The sensitivity of the filter paper method was compared with that of whole serum in the detection of HBsAg and antic using ELISA technique. It was found that analysis of eluates of blood spotted on filter paper should be recommended in field surveys and of HBsAg screening prior to an immunization campaign. On the other hand, in the detection of anti HBc the eluted technique is less sensitive and should not be performed if accurate epidemiological data are to be collected.

Intra familial spread of asymptomatic hepatitis B in Alexandria.

A total of 107 family members were examined for HBsAg 86 members were in families with a persistent carrier index and 21 of them were in families free from a carrier index. Rate of HBsAg transmission was 100% in families with a carrier index and absent in those free from a carrier. Horizontal transmission of hepatitis B virus infection reached about 80% in the total sample examined. All babies born to a carrier mothers became positive at one year of age stressing the importance of screening of the mother in the planning for vaccination programmes for the prevention of hepatitis B infection in newly-born.

Chronic hepatitis B antigenaemia in bilharzial patients treated with Praziquantel.

One hundred and fifty two bilharzial patients together with one hundred and eighty four individuals as free controls were tested for HBsAg using ELISA technique. 6.6% of the former were carriers compared to only 2.2% in the later. It was found that past history of antibilharzial therapy, jaundice and presence of hepatosplenomegaly increased the risk of contracting HB virus infection. Praziquantel therapy showed 60% parasitological cure rate and 90 reduction in the mean egg count of bilharzial carriers of HBV infection. It improved both simple and early hepato-intestinal schistosomiasis as 5 out of 10 HBV carriers became free either from schistosoma ova or HBsAg after 6 months of treatment. In this work all chronic bilharzial carriers (5) had hepatosplenomegaly, 1 patient showed parasitological cure after treatment and the other four patients had a reduction in the mean egg count denoting the failure of praziquantel in improving their immunologic status and thus still HBsAg carriers.