Hepatitis A Virus Antibodies Research Articles

Hepatitis A and B Seroimmunity in Vaccinated Children With Cirrhosis: Presidential Poster Award

Introduction: Superinfection with vaccine-preventable virus like hepatitis A virus (HAV) or hepatitis B virus (HBV) in patients with cirrhosis may induce rapid decompensation. Cirrhotic patients achieve lower response to HBV vaccination compared to healthy adults. HAV antibody titer is lower in patients with decompensated cirrhosis versus compensated cirrhosis. Our study aims to assess the incidence of hepatitis B surface antibody (HBV S Ab) titer (Ab QN) < 10 IU/l and non-reactive hepatitis A antibody (HAV Ab) titer (Ab QL) in vaccinated children with cirrhosis. Methods: All children, between ages 6 months and 17 years, with biopsy proven cirrhosis or clinically evident portal hypertension (CEPH) as defined by Childhood Liver Disease Research Network, who have confirmed completion of 3 dose HBV vaccination series and/or 2 dose HAV vaccination series were prospectively enrolled in our study. Children with past or present medical history of HAV or HBV infection and children with non-cirrhotic causes of portal hypertension were excluded. Once enrolled, we reviewed their basic demographics, physical exam findings, endoscopic findings, and lab results including HAV Ab QL and HBV S Ab QN from EMR. Results: So far, we have enrolled 12 patients, 4 boys and 8 girls with a mean age of 9.33 years. Ten patients have underlying diagnosis of biliary atresia. Half of these patients have biopsy proven cirrhosis. Onethird of our patients have platelet level < 150 k/cumm and half of our patients have splenomegaly on physical exam. In our preliminary data, the incidence of HBV S Ab < 10 IU/l is 41.7% and the incidence of non-reactive HAV Ab is 16.7%. All children with HBV S Ab < 10 IU/l and non-reactive HAV Ab are older than 5 years of age. The incidence of HBV S Ab < 10 IU/l and non-reactive HAV Ab in children older than 5 years of age is 62.5% and 25% respectively. All children found to have non-reactive HAV Ab are African American. Low HBV S Ab were present in 50% of children with documented splenomegaly compared to 33% without splenomegaly. Similarly, 60% of children with thrombocytopenia had HBV S Ab < 10 IU/l. Conclusion: There is a high incidence of low immune reactivity to HBV and HAV vaccination in children with cirrhosis. This reactivity seems to be lost with increasing age of the patients. Low HBV S Ab and non-reactive HAV Ab are associated with age > 5 years and African American race.1052 Figure 1 No Caption available.

Seroprevalence of Hepatitis A Virus among Healthy Individuals in Birjand, Eastern Region of Iran

Background: Hepatitis A virus (HAV) is an epidemiological important infectious agent in the world. HAV incidence can be controlled by cognizance of the geographic distribution pattern. Objectives: The aim of this study was to evaluate the frequency of HAV infection in Birjand. Methods: A total of 496 healthy individuals (mean age: 39.34 ± 15.47, range: 15 - 70 years, M/F ratio: 0.68) were randomly enrolled in this cross-sectional study. Demographic data were collected and the presence of anti-HAV total antibody was determined by the enzyme linked immunosorbent assay (ELISA). Results: Overall, the prevalence of positive serum anti-HAV antibody was 92.78%, however, the rate for 15 - 24 years subjects was 69%. There was a significant positive correlation between presence of anti-HAV antibody with age (P < 0.001), marriage (P < 0.001), education (P = 0.001) and anti-Hbc antibodies (P = 0.007). Conclusions: The result of this study showed a high prevalence of HAV antibody in most people, except for young adults, which can be an alarming sign for a higher rate of complicated HAV infections in the future and needs a proper strategy.

Pre-vaccine plasma levels of soluble inflammatory indices negatively predict responses to HAV, HBV, and tetanus vaccines in HCV and HIV infection

BackgroundChronic hepatitis C virus (HCV) and HIV infections are associated with impaired responses to neo-antigens contained in hepatitis A virus (HAV)/hepatitis B virus (HBV) vaccines, yet responsible mechanisms are unclear. MethodsACTG 5232 and CFAR0910 were clinical trials where pre-vaccine levels of plasma IP10, IL-6, sCD163 and sCD14 were measured in viremic HCV- (n = 15) or HIV-infected participants (n = 24) and uninfected controls (n = 10). Accelerated dosing HAV/HBV vaccine and tetanus booster were administered and antibody response was measured at 0, 1, 3, 8, and 24 weeks. ResultsPre-vaccine plasma IP10, IL-6, and sCD14 levels were elevated in both HCV and HIV-infected participants, while sCD163 was also elevated in HCV-infected participants. Pre-immunization tetanus antibody levels were lower in HIV-infected than in uninfected participants, while vaccine induced antibody responses were intact in HCV and HIV-infected participants. After HAV/HBV vaccination, HCV and HIV-infected participants had lower and less durable HAV and HBV antibody responses than uninfected controls.Among HCV-infected participants, pre-vaccine plasma IP10, IL-6, sCD14, and sCD163 levels inversely correlated with HAV, HBV and tetanus antibody responses after vaccine. Low HAV/HBV vaccine responses in HIV-infected participants prohibited assessment of immune correlates. ConclusionsDuring HCV and HIV infection markers of systemic inflammation reflect immune dysfunction as demonstrated by poor response to HAV/HBV neo-antigen vaccine.

Seroprevalence of anti-HAV total antibodies among workers in wastewater treatment plants.

Data on high frequency of hepatitis A virus (HAV) antibodies for wastewater treatment staff is contradictory. Literature lacks data on the seroprevalence of antibodies to HAV (anti-HAV) among workers in wastewater treatment plants (WWTPs) in Bulgaria. The aim of this study is to establish a specific humoral immune response to hepatitis A virus - anti-HAV total antibodies among staff in WWTPs. A complex study of health and working conditions included 110 subjects working in 3 WWTPs in Bulgaria (74% of all workers in the 3 studied WWTPs and 20% of all employees in Bulgaria registered in 2014 under the wastewater collection, discharge and treatment code of economic activity). Workers had been differentiated in 3 groups on the basis of their occupational work: operators, support staff and other workers exposed to biological agents. Venous blood from all 110 subjects was tested once for carriers of HAV antibodies. Anti-HAV total antibodies were found for 52.7% of workers in WWTPs. There is a positive association between activity performed in WWTPs (operators, maintenance personnel and others exposed) and a positive one for the presence of anti-HAV (Chi2 = 6.882, df = 2, p = 0.032). Odds ratio (OR) for hepatitis A increases 2.9 times in the group of operators vs. others exposed to biological agents in WWTPs (OR = 2.914, 95% confidence interval (CI): 1.149-7.393, Fisher's p = 0.039). Odds ratio for hepatitis A increases 4.3 times in the group of support staff from WWTPs vs. others exposed to biological agents in WWTP (OR = 4.295, 95% CI: 1.075-17.167, Fisher's p = 0.049). Higher frequency of anti-HAV antibodies among operators and maintenance personnel at WWTPs has been established as compared to other workers exposed to biological agents in WWTPs. There is a positive association between increasing age of the workers and the presence of anti-HAV. Int J Occup Med Environ Health 2018;31(3):307-315.

The seroprevalence of hepatitis A in Istanbul, Turkey

Objective: Hepatitis A, a leading cause of enterically transmitted acute viral hepatitis throughout the world, has changed its pattern in developing countries. The objective of this study is to determine the current seroprevalence of hepatitis A virus (HAV) for different age groups in Istanbul, Turkey. Material and Methods: Serum samples of 3,868 patients, which had been previously taken, were used to determine anti-HAV IgG levels by the microparticle enzyme immunoassay (MPEIA) method (Architect SR i1000 and i2000, Abbott Diagnostics, Germany) between January 2011 and December 2013. Results: The prevalence of total anti-HAV antibodies was 64.8% for all patients. Among the 3,868 serum samples tested, 54% were from male patients and 46 % were from female patients. Seropositivity rates among the age groups were determined and anti- HAV antibody positivity rates were 55% for the 0-16 age group; 47% for the 17-30 age group; 73.5% for the 31-45 age group and the seroprevalence increased significantly from 50% (972/1944) in 0 to 30 years old to 89% in patients older than 46 years. Conclusion: The low seronegativity rates in young adults, show this group to be at high risk of acquiring an HAV infection. The results support the routine vaccination of children and the seronegative young adults against HAV.

Evaluation of Lactobacillus coryniformis CECT5711 strain as a coadjuvant in a vaccination process: a randomised clinical trial in healthy adults

BackgroundAlthough the effects of probiotics on the immune system have been extensively evaluated under disease states, their role in healthy situations remains unclear, since changes are hardly expected under immunological homeostasis. EFSA indicates that vaccination protocols could be used to evaluate the potential role of probiotics to improve the immune response against antigen challenges. The aim of the study was to evaluate the effect of Lactobacillus coryniformis CECT5711 (Lc) on the specific immunity of healthy volunteers undergoing vaccination with Hepatitis A virus (HAV).MethodsOne hundred twenty-three healthy adults were randomised into three groups to follow a 6-week (wk) intervention and all received an intramuscular HAV vaccine 2 weeks after starting the intervention: 1) PRO1 received Lc for 2weeks (1 capsule/day; 3 × 109 CFU/capsule) and placebo capsules after vaccination; 2) PRO2 received a daily capsule of Lc (3 × 109 cfu/day) before and after the challenge; 3) Control group (C) received a daily placebo capsule before and after the vaccine. Blood samples were collected at the beginning (visit 1; V1) and after 2 (V2) and 6 weeks (V3) of the intervention. At each visit, lymphocyte subset counts and cytokine levels were analysed. Specific HAV antibodies were analysed at V1 and V3. To evaluate differences between groups, one-way ANOVA with Bonferroni post-hoc test were used regarding lymphocyte subset counts and specific HAV antibodies production, and Friedman test of related samples and Kendall concordance coefficient for cytokines production. Chi square test was used to analyse seroconversion rates.ResultsSpecific HAV antibodies were significantly higher in PRO1 (50.54 ± 29.57) compared to C (36.23 ± 16.45) (P = 0.017) and showed an intermediate value in PRO2 (41.61 ± 15.74). Seroconversion rates were similar in the three groups (97.3, 92.3 and 97.4% in C, PRO1 and PRO2 respectively). Memory T-helper lymphocytes increased in V3 vs. V1 (P = 0.032) in PRO2. No differences were found in cytokine concentrations.ConclusionMixed results have been found regarding the usefulness of Lc supplementation to increase the antigen-specific antibody response to an immune challenge. Clinical trial registration number: EudraCT Number 2016-000183-42. Registered 19 January 2016. Retrospectively registered.

Hepatitis A and B screening and vaccination rates among patients with chronic liver disease

Vaccinations against hepatitis A virus (HAV) and hepatitis B virus (HBV) are recommended for patients with chronic liver disease (CLD), yet implementation of these recommendations is lacking. This study reviewed HAV and HBV antibody testing and vaccination status of patients with CLD. In 2008, we began using pre-printed liver order sets, which included vaccination options. We compared Scott & White liver clinic CLD patient records from 2005 (238) with patient records from 2008 (792). Screening rates for immunity and vaccination rates of those lacking immunity were calculated. In 2005, 66% of CLD patients were screened for HAV immunity. In 2008, 56% of CLD patients were screened. The HAV vaccination completion rate was 37% in 2005, while in 2008, the rate was 46%. In 2005, 66% of CLD patients were screened for HBV immunity; in 2008, 56 % CLD patients were screened. The HBV vaccination completion rate was 26% in 2005 compared with 36% in 2008. Although there was a lower percentage of screening in 2008, the overall number of patients tripled between 2005 and 2008. There was a significant increase in the total number of patients screened and vaccinated in 2008. Some physicians may have vaccinated their patients without checking for immunity. In January 2008, we implemented pre-printed order sets with checkboxes to help remind providers to order labs to screen for immunity against HAV and HBV and to order vaccinations for those who lacked immunity. The use of these sets may have aided in the increase of vaccination completion rates.

Hepatitis A Antibody Seroprevalence in a Selected Kenyan Pediatric Population

The incidence of infection by Hepatitis A virus shows regional variation being highest in developing countries. Determination of age specific Hepatitis A virus (HAV) seroprevalence and the associated risk factors would help better plan for national preventive strategies including vaccination. We carried out a cross-sectional study on 300 children from Nairobi city, Kenya during the years 2003-2004. The age range of the children was 2 - 14 years and were from low and high socioeconomic status (SES) families. The indicators of SES included employment status, residence, number of children per patient’s household, parents’ level of education and source of drinking water. SES was encoded and analysed using Statistical Program for Social Sciences (SSPS) version 16.0. Seroprevalence increased significantly with advancing age. Seropositivity of HAV antibodies was significantly higher among children of low SES, 77.6% by the age of 14 years compared to children of high SES, 38.9% by the same age. Crowded household and parental education were significantly associated with high seropositivity and seronegativity respectively. There is significant rate of seronegativity amongst the studied population especially those from richer backgrounds making them more susceptible to severe infection in future with concomitant complications. We propose that revision of national vaccination program should be considered to include Hepatitis A vaccination.

Epidemiology of hepatitis E virus infection during pregnancy in Benin.

Hepatitis E virus (HEV) is the cause of enterically transmitted non-A, non-C hepatitis (an infection that is particularly severe during pregnancy) in tropical and subtropical countries. As there are no published data concerning the prevalence of HEV antibodies in Benin, their presence was investigated in pregnant women undergoing routine HIV screening in a rural area in northern Benin and in pregnant women with acute non-A, non-C hepatitis. A total of 278 serum samples were collected from asymptomatic pregnant women in 2011 were tested for HEV and hepatitis A virus (HAV) antibodies, and the HEV IgM-positive samples were further tested for HEV-RNA. A further seven samples of pregnant women with acute non-A, non-C hepatitis collected during episodes of acute hepatitis in 2005 were also analysed. Of the 278 samples collected in 2011, 16.19% were positive for HEV IgG and 1.44% for HEV IgM (none positive for HEV-RNA), and 99.64% were positive for total HAV antibodies (none positive for HAV IgM). Six of the seven samples collected in 2005 were positive for HEV IgG and IgM, and two were also positive for HEV-RNA. The circulation of HEV infection is significant among pregnant women in Benin, in whom the consequences may be fatal.

Socioeconomic inequities and hepatitis A virus infection in Western Brazilian Amazonian children: spatial distribution and associated factors.

BackgroundHepatitis A is still a neglected health problem in the world. The most affected areas are the ones with disadvantaged socioeconomic conditions. In Brazil, seroprevalence studies showed that 64.7 % of the general population has antibodies against HAV (hepatitis A virus), and the Amazon region has the highest seroprevalence in the country.MethodsIn the present study the seroprevalence of total HAV antibodies in children between 1 and 5 years old residing in the urban area of Assis Brasil, Acre was measured and spatial distribution of several socioeconomic inequities was evaluated.ResultsIn the year of 2011, seroprevalence rate was 16.66 %. Factors associated with having a positive serology identified by multivariate analysis were being of indigenous ethnicity [adjusted Odds Ratio (aOR) = 3.27, CI 1.45–7.28], usage of water from the public system (aOR = 8.18, CI 1.07–62.53), living in a house not located in a street (aOR = 3.48, CI 1.54–7.87), and child age over 4 years old (aOR = 2.43, CI 1.23–4.79). The distribution of seropositive children was clustered in the eastern part of the city, where several socioeconomic inequities (lack of flushed toilets, lack of piped water inside the household and susceptibility of the household to flooding during rain, low maternal education, having wood or ground floor at home, and not owning a house, lack of piped water at home, and type of drinking water) also clustered.ConclusionsThe findings highlight that sanitation and water treatment still need improvement in the Brazilian Amazon, and that socioeconomic development is warranted in order to decrease this and other infectious diseases.Electronic supplementary materialThe online version of this article (doi:10.1186/s12879-015-1164-9) contains supplementary material, which is available to authorized users.

Hepatitis A seroprevalence in preschool children in Assis Brazil, Acre, Brazil, in 2003 and 2010.

The Amazon region has the highest seroprevalence of hepatitis A virus (HAV) in Brazil. In the present study, the seroprevalence of total HAV antibodies in two groups, composed of 147 and 254 children between 1 and 5 years old in Assis Brasil, Acre, was measured in 2003 and 2010, respectively, and compared with socio-economic changes in the city. In 2003, the HAV seroprevalence rate was 26.5%, while in 2010, it was 22.4%. There was an overall improvement in socio-economic and sanitary conditions, with the exception of open sewage. In 2003, factors associated with positive serology were child age (aOR [adjusted odds ratio] 1.84; 95% CI: 1.28-2.64), having a latrine or not having a toilet at home (aOR 4.73; 95% CI: 1.06-21.17) and the treatment of drinking water with chlorine (aOR 0.26; 95% CI: 0.07-0.92). In 2010, the main factors associated with positive serology were using rivers, streams and rainwater as sources of water for domestic purposes (aOR 24.36; 95% CI: 3.69-160.85); having a wooden or ground floor at home (OR 2.51; 95% CI: 1.11-5.69) and child age (aOR 2.33; 95% CI: 1.66-3.28). In the Brazilian Amazon, sanitation and water treatment still require improvement and socio-economic development is warranted in order to decrease hepatitis A transmission.

Seroprevalence for Hepatitis E and Other Viral Hepatitides among Diverse Populations, Malawi

Data on prevalence of hepatitis E virus (HEV) in Malawi is limited. We tested blood samples from HIV-uninfected and -infected populations of women and men enrolled in research studies in Malawi during 1989-2008 to determine the seroprevalence of HEV, hepatitis A virus (HAV), hepatitis B virus (HBV), and hepatitis C virus (HCV). Samples were tested for IgG against HEV, total antibodies against HAV and HCV, and presence of HBV surface antigens. Of 800 samples tested, 16.5% were positive for HEV IgG, 99.6% were positive for HAV antibodies, 7.5% were positive for HBV surface antigen, and 7.1% were positive for HCV antibodies. No clear trends over time were observed in the seroprevalence of HEV, and HIV status was not associated with hepatitis seroprevalence. These preliminary data suggest that the seroprevalence of HEV is high in Malawi; the clinical effects may be unrecognized or routinely misclassified.

Seroprevalence of Hepatitis A and E Virus Infections Among Healthy Population in Shiraz, Southern Iran.

Background:Enterically-transmitted acute viral hepatitis is caused predominantly by hepatitis A virus (HAV) and hepatitis E virus (HEV). The prevalence of HEV and HAV infections varies in different geographical regions.Objectives:This study was conducted to determine the prevalence of HEV and HAV infections among Iranian healthy individuals in southern Iran.Patients and Methods:Totally, 1030 samples were collected from healthy subjects in schools, those referred to tertiary outpatient clinics and health centers in Shiraz between November 2011 and May 2012. Their ages ranged between six months and 95 years. The presence of total anti-HAV and anti-HEV immunoglobulin M (IgM) in plasma was assessed by ELISA.Results:The results showed that 66.2% and 0.6% of the general population in this area were positive for total anti-HAV and IgM antibodies by ELISA, respectively. As seen, 13.4% and 0.9% were positive for total anti-HEV and IgM antibodies, respectively. The difference in total anti-HAV and anti-HEV antibodies was significant among the age groups (P < 0.001).Conclusions:This study showed that the prevalence rates of HAV and HEV antibodies were positively correlated with age. The results demonstrated that the infection with these two viruses in the region was high and some high-risk individuals including females at child-bearing age were more susceptible. HAV vaccination could be recommended for antibody-negative adults.

Hepatitis A and B among young persons who inject drugs—Vaccination, past, and present infection

BackgroundOur study aims were to assess hepatitis A virus (HAV) and hepatitis B virus (HBV) susceptibility and infection among young persons who inject drugs (PWID) who may have been vaccinated as children and to evaluate self-report of HAV and HBV vaccination. MethodsWe recruited PWID aged 18–40 years-old in San Diego during 2009 and 2010 and collected demographic, socioeconomic, health, and behavioral factors. Participants were asked if they had been vaccinated against HAV and HBV, and serum samples were collected for HAV and HBV serologic testing. ResultsOf 519 participants, 365 (72%) were male, 252 (49%) were white non-Hispanic, 38 (7%) were Black non-Hispanic, 138 (27%) were White Hispanic, and 22 (4%) were born outside the U. S. Of the total participants, 245 (47%) had surface hepatitis B antibody (anti-HBs) titers <10mIU/ml (i.e., HBV susceptible) and 325 (63%) had no detectable HAV antibodies (HAV susceptible). Hepatitis B surface antigen was detected in 7 (1%) of total participants; and 135 (26%) were anti-HCV-antibody positive. Compared to serologic findings, self-report of HBV and HAV vaccination was 71% and 41% sensitive, and 58% and 73% specific, respectively. ConclusionHAV and HBV antibodies in half or more of this young PWID population did not have levels indicative of protection, and about a quarter had HCV infection, putting them at risk for complications resulting from co-infection with HAV or HBV. Programs serving this population should vaccinate PWIDs against HAV and HBV and not rely on self-report of vaccination.

Hepatitis A virus vaccination strategy and pre-immunization screening of Bangladeshi children

Background: HAV infection is endemic in many developing countries like India, Pakistan, Nepal etc. Several seroprevalence studies show high rates of sero-positivity among children by sub-clinical infection. Therefore mass vaccination against HAV has not been recommended in endemic countries. Objective: To determine whether routine hepatitis A vaccination is indicated for all Bangladeshi children &amp; also to know whether pre-vaccination screening is necessary. Materials &amp; Methods: Serum samples from 254 children aged between 1-15 years were tested for antibody (IgM &amp; IgG) against hepatitis A virus (HAV) to determine the seroprevalence of HAV antibody and do a cost-benefit analysis for decision making about vaccination against HAV among the children of Bangladesh. Results: Hepatitis A virus antibody was positive in 141 (55.5%) of 254 children. Age-specific sero-prevalence was 13 (23.2%) of 56 in 1-3 year, 64 (55.2%) of 116 in 3-5 year, 39 (70.9%) of 55 in 5-10 year &amp; 25 (92.6%) of 27 in 10-15 year age group. Cost benefit analysis showed that the total cost of screening followed by vaccination was almost 1.8 times less than the total cost of vaccination of all children without screening. Conclusions: Majority of the children were found sero-positive against HAV around 15 year of age. Therefore mass vaccination against HAV may not be required for Bangladeshi children.DOI: http://dx.doi.org/10.3329/bjms.v14i1.21561 Bangladesh Journal of Medical Science Vol.14(1) 2015 p.65-69

Hepatitis A infection in patients with chronic viral liver disease: a cross-sectional study in Jahrom, Iran.

Infection with hepatitis A virus (HAV) in patient with chronic liver disease (CLD; due to hepatitis B or hepatitis C) may cause severe disease and fulminant liver failure. This study aimed to determine the seroprevalence of HAV antibodies in patients infected with HCV or HBV in Iran (Jahrom city). A total of 159 patients with underlying CLD were recruited between September 2012 and February 2013. Serum samples were collected from each patient and tested for anti-HAV using enzyme-linked immunosorbent assay (ELISA). The overall seroprevalence of total anti-HAV was 79·2%. Patients aged 20-30 years had the lowest (28·3%) anti-HAV seropositivity and those aged >50 years had the highest (95%) seropositivity. The overall prevalence of anti-HAV in patients with chronic HCV and HBV infection was 93·7% and 77·1%, respectively. The anti-HAV seropositivity in liver cirrhosis patients was 100% compared to CLD patients. Because of low HAV immunity in younger CLD patients, vaccination against HAV should be considered.

Long-Term Persistence of Hepatitis A Antibodies in Pediatric HIV-Infected Patients after Primary Immunization: Association with Immunological Profile and Response to Revaccination

Background: We analyzed the persistence of hepatitis A virus (HAV) antibodies 7 years after primary immunization in pediatric HIV-positive patients and its association with the immunological profile. Methods: 29 vertically HIV-infected adolescents (median age, 12.9 years) were enrolled. All of them had been HAV-vaccinated with two HAV vaccine doses 7 years before and all had seroconverted. HAV antibodies were measured by electrochemiluminescence. Lymphocyte immunophenotyping was performed by flow cytometry. Adolescents who lost HAV antibodies were revaccinated. Results: 23/29 patients (79.3%) persisted HAV seropositive (HAV antibodies≥20mlU/mL) 7 years after primary immunization. Age, gender, clinical progression of HIV infection, median viral load, and antiretroviral therapy were similar between those who persisted HAV seropositive and those who lost seropositivity. HIV adolescents who lost HAV antibodies had lower median CD4+ T cells/mm3 (200 vs. 634, p=0.004), lower median B cells/mm3 (103 vs. 335, p<0.001), lower median NK cells/mm3 (67 vs. 209, p=0.002), lower median percentage of naive CD4+ T cells (20% vs. 30%, p=0.026), lower median percentage of naive B cells (52% vs. 68%, p=0.009), higher median percentage of activated memory B cells (19% vs. 7%, p=0.004), higher median percentage of activated CD8+ T cells (51% vs. 22%, p=0.002), and higher median percentage of exhausted memory B cells (23% vs. 8%, p=0.031) than HAV-positive adolescents. 83.3% adolescents responded to revaccination. Conclusion: Persistence of HAV antibodies occurred in 79.3% of patients. Both antibody maintenance and response to revaccination are closely associated with low immune activation and adequate CD4+ T and B cell levels.

Sero-Prevelance of antibodies to hepatitis a virus among australian blood donors

<h3>Aim</h3> Australia has a low incidence of hepatitis A virus (HAV), with the majority of cases in travellers. Nonetheless, the sero-prevalence of antibodies against HAV among Victorians has increased over the last two decades, likely to be a result of vaccination and increased travel/immigration. This study measured the prevelance of HAV antibodies in blood donors from around Australia to determine if a similar rate exists in other states. <h3>Methods</h3> Samples were collected from donors between January and July 2011 from Australian capital cities. All samples (<i>n</i> = 2109) were tested with a commercially available enzyme immunoassay for total anti-HAV antibody (levels ≥ 20IU/mL were considered sero-positive). <h3>Results</h3> Anti-HAV antibody was detected in 51.4% (95% CI 49.27-53.53%) of donors. Some variability was observed between cities; the highest rates were seen in Sydney donors (57.33%; 95% CI 51.74-62.93%), while the lowest in donors from Brisbane (43.67%; 95% CI 38.05-49.28%). Not surprisingly, sero-prevelance increased with increasing donor age. <h3>Conclusions</h3> This study demonstrated that over half of donors tested had anti-HAV antibodies, with relatively high rates in all capital cities. Given increased HAV vaccination rates, measuring naturally-acquired HAV infection in blood donors has become increasingly difficult and a serological test discriminating naturally-occurring from vaccine-induced immunity may be of interest.

Seroprevalence of hepatitis A virus infection in different age groups of children

Context: Hepatitis A is one of the most common causes of hepatitis in the pediatric age group and the most common cause of fulminant hepatic failure (FHF) among children in India. Hepatitis A is a waterborne disease. High endemicity obviates the need for vaccine in the community. Aims: We studied 116 children in the outpatient department (OPD) to know the seroprevalence of hepatitis A virus (HAV), total antibodies, and the effect of various demographic and water sanitation variables on it. Settings and Design: Children attending the pediatric OPD with minor problems in a medical college hospital were chosen for this study. It is a descriptive, cross-sectional, and seroepidemiologic investigative study. Materials and Methods: Blood samples of randomly selected children were collected and competitive enzyme-linked immunosorbent assay (ELISA) test was done for the detection of total anti-HAV antibodies, [both immunoglobulin M (IgM) and immunoglobulin G (IgG)], using a commercially available ELISA kit. Dia.Pro (Diagnostic Bioprobes srl via Columella n° 31 20128 Millano, Italy). Statistical Analysis Used: Statistical analysis was performed by the chi-square test using Epi Info software 3.5.4 version (2012) [Center for disease control and prevention (CDC), Atlanta, Georgia (USA)]. Results: Seroprevalence in children from the upper social class was 54.5% versus 87.2% in the lower social class ( P = 0.00075). 90.9% of the children with rural background were seropositive compared to 77.1% of children with urban background. The mother's education above and below secondary level had a seropositivity for HAV in children up to 69.23% and 87.1%, respectively. The method of water treatment using boiled water, mechanical filtration, filtration plus ultraviolet (UV) light treatment, and no treatment had a seropositivity of 50.0%, 83.33%, 37.5%, and 84%, respectively, ( P = 0.0036). Seropositivity was the highest when the water source was municipal bore well pipeline (88.88%), followed by municipal dam water through pipeline (79.16%), and personal bore well (68.16%) ( P = 0.026). Conclusion: Children of this geographical area have high seroprevalence for HAV antibodies at a younger age with a significant difference between their social classes, water sources, and water treatment methods.

Multiple Factors Contribute to Positive Results for Hepatitis A Virus Immunoglobulin M Antibody

In the United States, a successful vaccination program for hepatitis A virus (HAV) infection has decreased both its incidence and the true positive rate for diagnostic immunoglobulin M (IgM) antibody to HAV in acute hepatitis. To survey positive results of HAV IgM tests and determine the effect of changing ordering options. We reviewed all positive results for IgM antibody to HAV between January 2007 and December 2010. Patient demographics, clinical history, and laboratory data were recorded and the encounter, order, and reason for test reviewed. Each result was categorized as indicating acute, recent, resolved, or indeterminate HAV infection. A total of 10,735 tests were performed; 35 patients had 49 positive results. Most positive test results were associated with outpatient visits and were ordered in the assessment of patients with liver disease, but not clinical acute hepatitis. In the final analysis, 4 patients had acute hepatitis A and 20 individual patients had recent and/or resolved hepatitis. All but 1 of the remaining 11 patients had another established cause of liver disease with a positive IgM HAV antibody test result; data to determine causality were insufficient. The total number of tests requested annually decreased more than 35% with the introduction of computerized physician order entry. Current assays for IgM HAV antibodies are overused in the absence of clinical acute hepatitis; future clinical decision support may improve patterns of order entry. Most patients have findings consistent with HAV exposure but not acute hepatitis; dormant viral infection may be a continuing source of antigen.