Infantile Vaccination Research Articles

Hepatitis B Immunity Status among Healthcare Sciences Students, 20 Years after the Infantile Vaccination: The Most Appropriate Policy to Confer Full Protection.

Abstract 
 Background. During recent years, an increasing number of previously vaccinated children against hepatitis B (HBV) may begin activities as healthcare sciences students (HSS), so, at the higher risk of HBV infection. Therefore, documenting their immunity at before training was recommended. To evaluate their immunity status, as well as measuring the presence of immunological memory and protection through administering 1-to-3 additional doses of HBV vaccine among HSS who have been immunized at childhood, this study was conducted.
 Subjects and Methods. The vaccination status of the accepted HSS was documented by reviewing their vaccination record card. HBV infection markers at before, and following 1-to3 dose of HBV vaccine were measured using ELISA. Simple descriptive statistical methods were used to analyze collected data.
 Results. Totally, 274 HSS, 59.1% female, with mean age 23.8 years were included. Of those, 228 in infancy, and 46 within last 12-years have been immunized. From 228 infantile immunized students,103 with 1-to-3 doses of HBV vaccine were vaccinated. Of 125 non-boosted HSS, 64 preserved their protective antibody titers. The proportion of protected students and their antibody levels were increased significantly and approached to 96.8% following 3-doses of booster injection.
 Conclusion. Nearly half of the vaccinated students had lost their protective antibody titers, but, the majority of them preserved their immunological memory, detected through anamnestic response to booster vaccination. To provide appropriate protection, universal vaccination with one-doses of HBV vaccine followed by serological monitoring to identify non-protected students for further management seems reasonable.

Comparative Effectiveness of Prophylactic Strategies for Perinatal Transmission of Hepatitis B Virus: A Network Meta-analysis of Randomized Controlled Trials.

BackgroundPerinatal transmission is the main route of hepatitis B virus (HBV) transmission. While several measures have been attempted as means of preventing perinatal HBV transmission, the optimal strategy remains inconclusive.MethodsWe conducted a comprehensive search, through December 2016, for randomized controlled trials (RCTs) that compared the following measures among pregnant women with HBV infection: placebo/none, active immunoprophylaxis (hepatitis B vaccine series starting at birth [HBVac]), passive-active immunoprophylaxis (hepatitis B immunoglobulin and vaccine [HBIG+HBVac]), prenatal HBIG administration (HBIG/HBIG+HBVac), and prenatal antiviral therapy (AVT/HBIG+HBVac). Direct, indirect, and network meta-analyses were performed for all treatment comparisons.ResultsFifteen RCTs involving 2706 infants of HBV carrier mothers were eligible for analysis. Network meta-analysis demonstrated similar results as direct and indirect comparisons. HBVac alone significantly reduced the risk of hepatitis B infection in infants of HBV carrier mothers (relative risk [RR], 0.32; 95% confidence interval [CI], 0.21–0.50). The combination of immunoglobulin with vaccine is superior to vaccine alone (RR, 0.37; 95% CI, 0.20–0.67). Prenatal HBIG administration and antiviral therapy offer further advantages over current passive-active immunoprophylaxis for infants of highly viremic (HBV DNA level higher than 2 × 105 IU/mL) mothers (RR, 0.47; 95% CI, 0.29–0.75; and RR, 0.31; 95% CI, 0.10–0.99, respectively). There was no significant publication bias.ConclusionsBased on the universal infantile vaccination program, HBIG for infants born to HBV carrier mothers further reduces transmission. For highly viremic mothers whose children are still at risk for transmission under current immunoprophylaxis, prenatal HBIG administration or antiviral therapy in late pregnancy may be considered if more long-term evidence supports its efficacy and safety.

Helicobacter pylori neutrophil-activating protein: a potential Treg modulator suppressing allergic asthma?

The ultimate aim of the immune system is to eliminate pathogens without being harmful to the host. But what if eliminating the pathogen in itself is discomforting for the host? One such emerging case is of Helicobacter pylori. Modern medicine, infantile vaccination, and ultra-hygienic conditions have led to progressive disappearance of H. pylori in different parts of the world. However, the adversities caused by H. pylori’s absence are much larger than those caused by its presence. Asthma is rising as an epidemic in last few decades and several reports suggest an inverse-relationship between H. pylori’s persistence and early-life onset asthma. Regulatory T cells play an important role in both the cases. This is further supported by experiments on mouse-models. Hence, need of the hour is to discern the relationship between H. pylori and its host and eliminating its negative impacts without disturbing our indigenous microbiota. To resolve whether H. pylori is a pathogen or an amphibiont is another important side. This review explores the biological basis of H. pylori-induced priming of immune system offering resistance to childhood-onset asthma. HP-NAP–Tregs interaction has been predicted using molecular docking and dynamic simulation.

Chronic hepatitis B infection in adolescents who received primary infantile vaccination

Hepatitis B virus (HBV) infection is a global health issue. Universal infantile hepatitis B (HB) vaccination is very efficacious. However, HBV infections among those immunized subjects have been reported. The long-term efficacy of postnatal passive-active HB vaccination in high-risk subjects is not well explored. A total of 8,733 senior high school students who were born after July 1987 were assayed for hepatitis B surface antigen (HBsAg) and antibodies to HBsAg (anti-HBs). The overall HBsAg and anti-HBs-positive rates were 1.9% and 48.3%, respectively. The HBsAg-positive rate was 15% in HB immunoglobulin (HBIG) recipients (adjusted odds ratio [OR]: 15.63; 95% confidence interval [CI]: 10.99-22.22). Among students who did not receive HBIG, there was a significantly negative association between HB vaccination dosage and HBsAg-positive rate (P for trend = 0.011). Adjusted ORs for those who received 4, 3, and 1 to 2 doses were 1.00, 1.52 (95% CI: 0.91-2.53), and 2.85 (95% CI: 1.39-5.81), respectively. Among HBIG recipients, the HBsAg-positive rate was significantly higher in subjects with maternal hepatitis B e antigen (HBeAg) positivity and who received HBIG off-schedule. A booster dose of HB vaccination was administered to 1974 HBsAg- and anti-HBs-negative subjects. Prebooster and a postbooster blood samples were drawn for anti-HBs quantification. The proportions of postbooster anti-HBs titer <10 mIU/mL was 27.9%. Subjects with prebooster anti-HBs titers of 1.0-9.9 mIU/mL had significantly higher postbooster anti-HBs titers than those with prebooster anti-HBs titers of <1.0 mIU/mL (P < 0.0001). Having maternal HBeAg positivity is the most important determinant for HBsAg positivity in adolescents who received postnatal passive-active HB vaccination 15 years before. A significant proportion of complete vaccinees may have lost their immunological memories against HBsAg.

Hepatitis B Virus Infection; A Vanishing Disease in Iranian Children

Hepatitis B virus (HBV) infection is the main cause of chronic liver disease (1) and at least 2 billion people are infected worldwide, while 350 million are chronic HBV carriers (1). The prevalence rate of HBV infection differs in various countries. In areas with a high prevalence (8% or more), the lifetime risk of exposure to the infection is around 60 and it typically occurs in infancy or childhood periods. China, South-East Asia, most of Africa and some parts of the Middle East have a high prevalence of HBV infection and the rate ranges from 8% to 15% (1, 2). Inter-mediate prevalence areas (2-7%) of infection occur across all age groups and most areas of Middle East countries, Eastern and Southern parts of Europe are in this category. There are also areas with low endemicity, i.e. lower than 2% prevalence in adults. These areas include North Amer-ica and Western Europe (1).HBV infection is still the main cause of chronic liver dis-ease in Iran (3), although the seroprevalence of HBV in-fection in Iran has decreased during the last two decades (4). The main risk factor for HBV transmission was pre-viously related to maternal-infantile transmission and high coverage infantile vaccination is the main cause for changes in the epidemiology of HBV infection (5). Given the importance of this interruption to HBV transmission in Iran, the HBV vaccination has been included in the ex-tended program of immunization (EPI) since 1993 (6, 7).Adibi

New globally faces of hepatitis B and C in the world.

Worldwide, infections with hepatitis B virus (HBV) and hepatitis C virus (HCV) have become a major cause of chronic hepatitis, cirrhosis and hepatocellular carcinoma (HCC) and the major global problems for public health in the world and Iran (1–3). HBV infection is the main cause of chronic liver disease in Iran (4) and the seroprevalence of HBV infection in Iran has been decreased during the last two decades (5). The main risk factor for HBV transmission was related to maternal-to-infantile transmission and the infantile vaccination with high coverage is the main cause for changes in epidemiology of HBV infection. But today, we have more risk factors for transmission in adulthood. The community contacts more in adolescence and the health policy makers should attend more for control of HBV infection. People awareness, risk factors modifications, harm reduction programmes in young addicted persons, vaccination against HBV in adults should be consider for control of HBV infection in future. We have less new cases, but we will have more cirrhotic cases and we need to consider the best therapy for prevention of HBV infection to end-stage phases. Therapy of HBV infection in which phase and which drugs are the debate. The goal of therapy in chronic hepatitis B (CHB) patients is sustained suppression of HBV viremia and decrease progression of liver disease to cirrhosis and HCC with the ultimate goal of improving survival. This can be pursued by maintaining constant inhibition of viral replication through a long term treatment with nucleos(t)ide analogs or by inducing, through the combined antiviral and immunomodulatory effects of interferon, a sustained immune response (6). Standard interferon is the oldest approved drug in therapy of HBV infection, but it has a limited response rate. Recently new published data have shown the better response with pegylated interferon in therapy of chronic HBV infection (7, 8). PEG-IFNα-2a has been licensed for the treatment of both HBeAg-positive and HBeAg-negative chronic HBV as a 48-week course, given by subcutaneous injection once weekly in a dosage of 180 mg. The main side effects of therapy with nucleos(t)ide analogs such as lamivudine, adefovir and entecavir, is emergence of resistance (9, 10). These events will decrease benefit of therapy with anti-viral agents. HBs Ag level in prediction of therapy response The main question was and is regarding how and when we can conclude the therapy in HBV infection is effective and we should continue or it is ineffective and we should discontinue it. During recent years serum HBsAg is hypothesized to be a marker for immunological response to therapy, independent of virological response as measured using HBV DNA levels, because of its correlation with intrahepatic HBV covalently closed circular (ccc) DNA, the main replicative template of HBV (11). HBsAg levels appear to differentiate patients in the inactive carrier state from those with active disease or from inactive carriers with a high probability of subsequent relapse. Furthermore, recent studies have shown that on- treatment HBsAg levels are predictive of a durable off-treatment response to peginterferon (PEG-IFN), and can accurately identify non-responders early during therapy, both in HBeAg-positive, and HBeAg-negative patients. Among those who underwent HBsAg loss within 6 years of follow-up, serum HBsAg levels were a better predictor than HBV DNA levels. Low serum levels of HBsAg, alone or in combination with HBV DNA levels, 1 year after HBeAg seroconversion can predict HBsAg loss in patients with HBV infection (12). Currently, multiple diagnostic assays are available for quantification of HBsAg. That we should use the validate method for diagnosis.

HLA and response to booster hepatitis B vaccination in anti-HBs-seronegative adolescents who had received primary infantile vaccination

To explore contemporarily genetic and non-genetic determinants of long-term immunological memory to hepatitis B (HB) vaccination, we conducted a case–control study nested in an adolescent cohort of booster recipients who had received primary infantile HB vaccination but with residual anti-HBs titers <10 mIU/mL at 15–18 years of age. High-resolution phenotypes of human leukocyte antigen (HLA)-A, -B, and -DRB1 loci were determined by sequence-specific oligonucleotide probe hybridization. After controlling for pre-booster anti-HBs levels, the absences of HLA- A*02 and - DRB1*08, simply expressed as A*02 − and - DRB1*08 −, and the presence of B*15 were significantly associated with elevated risks of non-response (post-booster anti-HBs titers < 10 mIU/mL) to booster vaccination. The adjusted odds ratios (ORs) were 3.85 (CI, 1.82–8.33), 4.55 (CI, 1.23–16.67), 3.59 (CI, 1.40–9.17), respectively. There was multiplicative synergism between A*02 and B*15 on the risk of non-response to booster vaccination. The multivariate-adjusted ORs for A*02 −/ B*15, A*02 −/ B*15 −, A*02/ B*15, and A*02/ B*15 − haplotypes were 20.39 ( p = 0.0003), 3.29 ( p = 0.007), 1.32 ( p > 0.05), and 1.0, respectively. Recent cigarette smoking and/or betel-quid chewing was associated with a 12-fold risk of non-response to booster vaccination. Further comparisons between responders and adolescents who had undetectable post-booster anti-HBs titers (<0.1 mIU/mL) demonstrated similar results. Our results indicated that response to booster HB vaccination as well as long-term immunological responses to HB vaccination are closely related with host genetic factors, and probably modified by recent substance use.

Ethnicity, substance use, and response to booster hepatitis B vaccination in anti-HBs-seronegative adolescents who had received primary infantile vaccination

In this revaccination study, we explored the determinants of response to booster hepatitis B (HB) vaccination in anti-HBs-seronegative adolescents who had received primary HB vaccination 15-18 years before. After controlling for prebooster anti-HBs levels, cigarette smoking, betel-quid chewing, alcohol drinking, and indigenous ethnicity were significantly associated with elevated risks of non-response to booster HB vaccination. The adjusted odds ratios (aORs) were 3.21 (CI: 1.33-7.84), 8.78 (CI: 2.03-37.94), 2.64 (CI: 1.15-6.02), and 2.46 (CI: 1.28-4.72), respectively. Among adolescents with undetectable prebooster anti-HBs titers, only indigenous ethnicity significantly associated with elevated risk, with an adjusted OR of 2.57 (CI: 1.20-5.54), of non-response to booster HB vaccination. On the contrary, the influences of cigarette smoking, betel-quid chewing, and alcohol drinking were restricted to adolescents with prebooster anti-HBs titers of 0.1-9.9mIU/mL. The corresponding multivariate-adjusted ORs were 5.70, 17.41, and 3.72, respectively. Adolescents who smoked cigarettes and chewed betel-quid were at highest risk of non-response (aOR, 25.3; CI: 2.97-215.7). A booster dose of HB vaccine may be insufficient to induce immunological response in healthy adolescents who had undetectable prebooster anti-HBs titers or who were of Malay-Polynesian ethnicity. Responses to booster vaccination are probably modified by recent cigarette smoking and/or betel-quid chewing.

Infantile Vaccination and the Secular Trend in Stature

Infantile Vaccination and the Secular Trend in Stature