Low Endemicity Of Hepatitis Research Articles

Coste-efectividad de la vacunación universal infantil frente a la hepatitis A en España: un enfoque dinámico

ObjectiveTo evaluate the cost-effectiveness of infant universal vaccination against hepatitis A in Spain. MethodUsing a dynamic model and decision tree model, a cost-effectiveness analysis was performed to compare three vaccination strategies against hepatitis A: non-vaccination strategy versus universal childhood vaccination of hepatitis A with one or two doses. The perspective of the study was that of the National Health System (NHS) and a lifetime horizon was considered. Both costs and effects were discounted at 3% per year. Health outcomes were measured in terms of quality adjusted life years (QALY) and the cost-effectiveness measure used was the incremental cost-effectiveness ratio (ICER). In addition, deterministic sensitivity analysis by scenarios was performed. ResultsIn the particular case of Spain, with low endemicity for hepatitis A, the difference in health outcomes between vaccination strategies (with 1 or 2 doses) and non-vaccination are practically non-existent, terms of QALY. In addition, the ICER obtained is high, exceeding the limits of willingness to pay from Spain (€22,000–25,000/QALY). The deterministic sensitivity analysis showed that the results are sensitive to the variations of the key parameters, although in no case the vaccination strategies are cost-effective. ConclusionsUniversal infant vaccination strategy against hepatitis A would not be a cost-effective option from the NHS perspective in Spain.

The frequency of occurrence anti-HAV antibodies to health employees – own observations

In the years 1997-2016, Poland was counted among the countries with a low and very low endemicity of hepatitis A. Based on the epidemiological data from NIZP–PZH (National Institute of Public Health - National Institute of Hygiene), since 2017, an increase in the incidence of hepatitis A has been observed in Poland. Considering the low number of cases by 2016 and a high percentage of seronegative persons, an increased risk of HAV infections should be expected. The aim of the project was to assess the presence of anti-HAV IgG antibodies in the employees of the Provincial Hospital for Infectious Diseases and Observation in Bydgoszcz. The study was conducted on 123 people who are employees of the hospital. The presence of anti-HAV antibodies was detected using HAV IgG Elisa FORTRESS DIAGNOSTICS kits. The presence of anti-HAV IgG antibodies was found in 28/123 (22.8%) subjects. Anti-HAV IgG antibodies were almost exclusively found in people over 40 years of age. Only one case involved a younger person. The low incidence of anti-HAV antibodies in the IgG class among medical personnel confirms the reasonableness of vaccinations against hepatitis A in this group.

Modeling the hepatitis A epidemiological transition in Brazil and Mexico

ABSTRACTBackground: Many low- to middle-income countries have completed or are in the process of transitioning from high or intermediate to low endemicity for hepatitis A virus (HAV). Because the risk of severe hepatitis A disease increases with age at infection, decreased incidence that leaves older children and adults susceptible to HAV infection may actually increase the population-level burden of disease from HAV. Mathematical models can be helpful for projecting future epidemiological profiles for HAV.Methods: An age-specific deterministic, dynamic compartmental transmission model with stratification by setting (rural versus urban) was calibrated with country-specific data on demography, urbanization, and seroprevalence of anti-HAV antibodies. HAV transmission was modeled as a function of setting-specific access to safe water. The model was then used to project various HAV-related epidemiological outcomes in Brazil and in Mexico from 1950 to 2050.Results: The projected epidemiological outcomes were qualitatively similar in the 2 countries. The age at the midpoint of population immunity (AMPI) increased considerably and the mean age of symptomatic HAV cases shifted from childhood to early adulthood. The projected overall incidence rate of HAV infections decreased by about two thirds as safe water access improved. However, the incidence rate of symptomatic HAV infections remained roughly the same over the projection period. The incidence rates of HAV infections (all and symptomatic alone) were projected to become similar in rural and urban settings in the next decades.Conclusion: This model featuring population age structure, urbanization and access to safe water as key contributors to the epidemiological transition for HAV was previously validated with data from Thailand and fits equally well with data from Latin American countries. Assuming no introduction of a vaccination program over the projection period, both Brazil and Mexico were projected to experience a continued decrease in HAV incidence rates without any substantial decrease in the incidence rates of symptomatic HAV infections.

Hepatitis E virus seroprevalence among hemodialysis and hemophiliac patients in Tunisia (North Africa).

The aims of this study are to determine seroprevalence of Hepatitis E virus (HEV) in Tunisian blood donors and to evaluate its risk of parenteral transmission. Sera collected from 426 blood donors were tested for HEV IgG by indirect ELISA. Individuals were recruited from two national transfusion centers, in the North and the South of the country. Seroprevalence of HEV IgG was then compared with two other groups with increased risk of exposure to parenterally transmitted agents: 80 hemophiliac and 286 hemodialysis patients. Among blood donors, the seroprevalence was estimated to be 4.5%. It was significantly higher in the hemophiliac and hemodialysis groups with 7.5% and 10.2%, respectively, (P = 0.002). No significant correlation was observed for this IgG 1 seroprevalence between age and sex among three studied groups. These results suggest that HEV has a high risk of parenteral transmission and confirm that the low endemicity of hepatitis E in Tunisia was observed.

Serological and molecular expression of Hepatitis B infection in patients with chronic Hepatitis C from Tunisia, North Africa

BackgroundThis study reports the prevalence and the viral aspects of HBV infection in HCV-positive patients from Tunisia, a country with intermediate and low endemicity for hepatitis B and C, respectively.ResultsHBV infection was assessed in the serum samples of 361 HCV-positive patients and compared to a group of HCV negative individuals. Serological markers were determined by ELISA tests and HBV DNA by real-time PCR. HBV serological markers were found in 43% and 44% of patients and controls, respectively. However, the serological and molecular expression of HBV infection differed in the two groups: The group of patients included more individuals with ongoing HBV infection, as defined by the presence of detectable HBsAg and or HBV DNA (17% and 12%, respectively). Furthermore, while most of the controls with ongoing HBV infection expressed HBsAg, the majority of HCV and HBV positive patients were HBsAg negative and HBV DNA positive. Genotyping of HCV isolates showed large predominance of subtype 1b as previously reported in Tunisia. Comparison of the replicative status of the two viruses found low HBV viral load in all co-infected patients as compared to patients with single HBV infection. In contrast, high levels of HCV viremia levels were observed in most of cases with no difference between the group of co-infected patients and the group with single HCV infection.ConclusionsThis study adds to the knowledge on the prevalence and the virological presentation of HCV/HBV dual infection, providing data from the North African region. It shows that, given the local epidemiology of the two viruses, co-infected patients are likely to have low replication levels of HBV suggesting a suppressive effect of HCV on HBV. In contrast, high replication levels for HCV were fond in most cases which indicate that the presence of circulating HBV-DNA does not necessarily influence HCV replication.

Molecular detection of hepatitis B virus (HBV) among voluntary blood donor's HBsAg positive in Shahrekord, Iran.

Hepatitis B virus, a common cause of viral hepatitis, consumes a large portion of health resources in developing countries. Hepatitis B virus (HBV) prevalence has been decreased dramatically in Iran population during the last decade, and now it is classified as having low endemicity for hepatitis B infection. Improvement of the people’s awareness about HBV risk factors, national vaccination program since 1993 for all neonates, and vaccination of high risk groups could be the cause of this decrease. In this investigation, we announce the detection of HBV- DNA sequence from 90 HBsAg positive blood donors in shahrekord by nested PCR, using specific primers of the surface antigen region of the HBV genome. Of the 11472 volunteer blood donors admitted to Shahrekord blood transfusion organization center in Iranduring 2007 - 2008, 90 specimens were positive for HBsAg. From 90 HBsAg positive serum samples, 75 specimens were positive in PCR. Key words: Blood donors, HBsAg positive, Hepatitis B, Iran, PCR, Shahrekord.

Epidemiological study of hepatitis A, B and C in the largest Afro-Brazilian isolated community

This study was conducted to estimate the prevalence and molecular epidemiological features of viral hepatitis A, B and C in the Kalunga population, which represents the largest Afro-Brazilian isolated community. Among 878 individuals studied, the overall prevalence of anti-hepatitis A virus antibodies was 80.9%, with a significant rise from 44.8% to near 100% between the first and fourth decade of life. Rates for hepatitis B surface antigen (HBsAg) and antibody to hepatitis B core antigen (anti-HBc) of 1.8% and 35.4%, respectively, were found. Increasing age, male gender, illiteracy and history of multiple sexual partners were associated with hepatitis B virus (HBV) infection. An occult HBV infection rate of 1.7% (5/295) was found among anti-HBc-positive individuals. HBV genotype A (subtype Aa) was dominant in this community. Only 5/878 individuals (0.6%) were positive for anti-hepatitis C virus (HCV). HCV RNA was detected in three of them, who were infected with genotype 1 (subtype 1a). These findings point out high, intermediate and low endemicity for hepatitis A, B and C, respectively, in the Kalunga community in Brazil. Circulation of HBV genotype A (subtype Aa) in this Afro-Brazilian isolated community indicates the introduction of this virus during the slave trade from Africa to Brazil.

Effectiveness of a hepatitis A vaccination program for migrant children in Amsterdam, The Netherlands (1992–2004)

ObjectiveTo evaluate the impact and effectiveness of risk-group vaccination against hepatitis A targeted at migrant children living in a country with low endemicity of hepatitis A. MethodsRetrospective population based data analysis. Routinely collected data on hepatitis A incidence in migrant children and other risk groups in Amsterdam from 1 January 1992 to 2004 were analyzed and related to exposure, immunity and vaccination coverage in migrant children. ResultsThe overall hepatitis A incidence in Amsterdam declined after a pediatric vaccine was introduced in 1997. This decline was seen in migrant children traveling to hepatitis A-endemic countries, contacts with hepatitis A patients, primary school students, injecting drug users, and persons with unknown source of infection, but not in men who have sex with men (MSM) or in travelers to endemic countries other than migrant children. ConclusionThe hepatitis A vaccination campaigns are effective: they reduce both import and secondary HAV cases. The campaigns could be more efficient and cost-effective if the hepatitis B vaccinations currently given to these groups were replaced by a combined hepatitis A and B vaccine. This would increase the hepatitis A vaccination coverage considerably and further reduce the hepatitis A incidence.

Wide Variety of Genotypes and Geographic Origins of Hepatitis B Virus in Belgian Children

ABSTRACTBackgroundBelgium is a country with low endemicity for hepatitis B virus (HBV) infection. Few data are available on genotypes or serotypes of HBV among infected children.MethodsThe S region of the hepatitis B virus genome was amplified and sequenced in 23 children treated with interferon‐α in Belgium. Nucleotide sequences were aligned and compared with other known sequences in a phylogenetic analysis.ResultsA high stability of the S gene was observed during treatment. Four genotypes were represented in this sample of Belgian patients (A, B, D, and E), reflecting the geographic diversity of origins.ConclusionsIn this series, the wide variety of geographic origins is confirmed by the molecular characteristics of HBV. In Belgium, HBV infection of children is currently essentially an imported infection.

Wide variety of genotypes and geographic origins of hepatitis B virus in Belgian children.

Belgium is a country with low endemicity for hepatitis B virus (HBV) infection. Few data are available on genotypes or serotypes of HBV among infected children. The S region of the hepatitis B virus genome was amplified and sequenced in 23 children treated with interferon-alpha in Belgium. Nucleotide sequences were aligned and compared with other known sequences in a phylogenetic analysis. A high stability of the S gene was observed during treatment. Four genotypes were represented in this sample of Belgian patients (A, B, D, and E), reflecting the geographic diversity of origins. In this series, the wide variety of geographic origins is confirmed by the molecular characteristics of HBV. In Belgium, HBV infection of children is currently essentially an imported infection.

Prevalence of hepatitis A, B, and C markers in school children of a rural area of Crete, Greece.

To determine the prevalence of hepatitis A, B, and C markers in children who were attending junior and senior high schools in a high risk area in rural Crete, Greece. Three-hundred and thirty-four children who attended the three junior schools and one senior high school in the Agios Vassilios province of Southern Crete were invited to participate in the study. Three hundred and four of them were tested for hepatitis A, B, and C markers. Hepatitis B (HBV) markers (HBsAg and anti-HBc) as well as hepatitis A (anti-HAV) and hepatitis (anti-HCV) antibodies were tested with commercial enzyme-linked immunosorbent assay kits. Six of the 304 children (1.97%) were found to be positive for anti-HAV, 1 (0.33%) to HBsAg, 7 (2.30%) to anti-HBc and none were found positive for anti-HCV. No significant differences were seen between the prevalence of anti-HAV antibodies in males (2%) and females (1.95%), and of anti-HBc antibodies in males (3.33%) and females (1.30%). The very low prevalence of anti-HAV is obviously due to the improved conditions of hygiene and it raises the question of the possible emergence of this disease at an older age and therefore appropriate preventative strategies should be considered. The low endemicity of hepatitis B in Crete in contrast to other areas of Greece also calls for a vaccination policy probably during adolescence. The absence of hepatitis C markers in the children in contrast to the observed higher prevalence of HCV-infected people in the adult population in the same rural area raises questions regarding possible sources of transmission of hepatitis C during the preceding years.

Selective risk group strategies in Europe

Most countries in northern and western Europe belong to areas with a low endemicity of hepatitis B virus (HBV). When HBV vaccines became available, these countries adopted a vaccination strategy that targeted groups at high risk of hepatitis B. However, it became obvious that this strategy, despite giving good protection to those who had been vaccinated, had largely failed. This was firstly because, with few exceptions (e.g. haemodialysis patients and haemophiliacs), only medical and dental workers were vaccinated in any great numbers, whereas only a few individuals in other risk groups were reached. Second, it was found that less than half of all hepatitis B cases occurred in individuals in typical high-risk groups. In Germany, for example, about three-quarters of all infections occur in people who would never be reached by the high-risk vaccination strategy, most of these individuals having been infected by heterosexual contact. Thus a universal vaccination strategy has to be implemented to control the spread of hepatitis B in the population and to eventually eliminate the disease.