Anti-HBs antibody status and some of its associated factors in dental health care workers in Tehran University of Medical Sciences: Anti-HBs Ab and associated factors in dental society

Background

Dental health care providers are at risk of infection with hepatitis B virus (HBV). Dentists can occupationally become infected with HBV through needle sticks or exposure to blood and other body fluids.

Objectives

To evaluate anti-HBs antibody titer in students, professors, clinical assistants and non-clinical staff of Faculty of Dentistry, Tehran University of Medical Sciences (TUMS), and to investigate the probable correlation between the level of immunity and a number of associated factors.

Patients and Methods

230 participants who had a history of previous HBV vaccination (receiving at least two doses of HBV vaccine) and a negative history of being infected with HBV were studied. Participants'' data were recorded using a checklist, and the level of antibody was measured by enzyme-linked immunosorbent assay (ELISA).

Results

While there existed statistically significant correlations between age, occupation, smoking, complete and scheduled vaccination and time of the last vaccination with the level of anti-HBs antibody, the correlation between gender and level of the antibody was not significant. Multiple regression analysis revealed significant association between immune response and age and time of the last vaccination.

Conclusions

Due to the significant correlation between younger age and anti-HBs antibody titer in our study, it makes sense to establish a mandatory complete and scheduled vaccination program for all members of dental society younger than 40 years.     

Hepatitis B virus (HBV) DNA levels and the management of HBV-infected health care workers

Different guidelines exist for the management of hepatitis B virus (HBV)-infected health care workers (HCWs). Various HBV DNA levels are used as a cutoff level to determine whether an HBV-infected HCW is allowed to perform exposure-prone procedures (EPPs) or not. In this paper we discuss the factors that determine HBV DNA levels and the implications of different HBV DNA cutoff levels for EPP performing HCWs. If the level of HBV DNA in the serum of HCWs is used to determine acceptability for the conduct of EPPs, it is necessary to take into account the variability in time of HBV DNA levels in HBV carriers and the reliability and reproducibility of the molecular diagnostic test involved. The issue of standardization has to be addressed, before a universal, maximum level of viraemia for EPP performing HCWs can be introduced.     

Hepatitis C virus antibodies are absent among high risk group of health care workers in Damascus Hospital

Background and study aims

Liver disease caused by hepatitis C virus (HCV) is one of the most serious health issues worldwide. The prevalence of HCV among health care workers (HCWs) is higher than normal population. Our aim is to determine the seroprevalence of HCV among this high-risk group in Damascus Hospital, Syria in 2016.

Hepatitis B virus and hepatitis C virus infection in healthcare workers

Approximately 3 million healthcare workers per year receive an injury with an occupational instrument, with around 2000000 exposures to hepatitis B virus(HBV) and 1000000 to hepatitis C virus(HCV). Although an effective HBV vaccine has been available since the early eighties, and despite the worldwide application of universal vaccination programs started in the early nineties, HBV still remains a prominent agent of morbidity and mortality. There is no vaccine to limit the diffusion of HCV infection, which progresses to chronicity in the majority of cases and is a major cause of morbidity and mortality worldwide due to a chronic liver disease. Healthcare workers are frequently exposed by a mucosal-cutaneous or percutaneous route to accidental contact with human blood and other potentially infectious biological materials while carrying out their occupational duties. Mucosal-cutaneous exposure occurs when the biological material of a potentially infected patient accidentally comes in contact with the mucous membranes of the eyes or mouth or with the skin of a healthcare worker. Percutaneous exposure occurs when an operator accidentally injures himself with a sharp contaminated object, like a needle, blade or other sharp medical instrument. About 75% of the total occupational exposure is percutaneous and 25% mucosal-cutaneous, the risk of infecting a healthcare worker being higher in percutaneous than in mucosal-cutaneous exposure. All healthcare workers should be considered for HBV vaccination and should meticulously apply the universal prophylactic measures to prevent exposure to HBV and HCV.     

我国乙型肝炎疫苗研究及接种的新进展

乙型肝炎病毒(Hepatitis B virus,HBV)引起的相关疾病仍然是困扰医疗界的一大难题,全球每年有(100～150)万人死于与HBV相关的疾病,尤其以慢性乙型肝炎者尚无有效的治疗方法,这使得接种乙型肝炎疫苗成为了目前防治乙型肝炎的最经济和有效的手段,乙型肝炎疫苗研究也因此有了长足发展。本文对乙型肝炎疫苗的现状及研究进展进行了整理,以提高临床医师对乙型肝炎疫苗的认识。     

乙型和丙型肝炎病毒感染与肝细胞癌

为探讨乙型和丙型肝炎病毒（ＨＢＶ和ＨＣＶ）感染与肝细胞癌（肝癌）发生的关系，采用ＥＬＩＳＡ和聚合酶链反应（ＰＣＲ）对沈阳地区１１７例肝癌、１０７例肝硬化和４５例血液透析患者血清进行了ＨＢＶ和ＨＣＶ血清标志及ＨＢＶＤＮＡ和ＨＣＶＲＮＡ检测，并采用限制性片段长度多态性对其中７３例ＨＣＶＲＮＡ阳性血清进行了ＨＣＶ基因分型。结果，肝癌组ＨＢＶ感染率（６０７％）显著高于ＨＣＶ感染率（３３３％，Ｐ＜００１），肝硬化组ＨＢＶ感染率（４３９％）明显高于ＨＣＶ感染率（２９０％，Ｐ＜００５）；血液透析组ＨＢＶ和ＨＣＶ重叠感染率（２６７％）明显高于肝硬化组（１０３％，Ｐ＜００５）；各组均以ＨＣＶⅡ型为主（６５２％～８００％），ＨＣＶⅢ型次之（２００％～３１４％）。结果提示：沈阳地区肝癌的诱发因素仍以ＨＢＶ为主，血液透析患者ＨＢＶ和ＨＣＶ重叠感染的机会更大，ＨＣＶⅡ型感染在本地区ＨＣＶ相关性肝癌和肝硬化的发生中可能起主要作用。     

慢性乙型肝炎患者中庚型肝炎病毒检测

目的了解慢性乙型肝炎中庚型肝炎病毒（ＨＧＶ）的感染率及其对病变程度和ＨＢＶ复制的影响。方法逆转录聚合酶链反应（ＲＴＰＣＲ）检测６５例经肝活检证实的慢性乙型肝炎患者血清中ＨＧＶＲＮＡ。结果有８例（１２．３％）慢性乙型肝炎患者合并ＨＧＶ感染,轻度、中度和重度患者中的ＨＧＶ检出率统计学处理差异无显著性,ＨＧＶ混合感染与其临床表现无相关性,ＨＧＶ阳性组与阴性组患者的肝功能改变相近。ＨＢｅＡｇ阳性组和ＨＢｅＡｇ阴性组患者的ＨＧＶ检出率亦相当。结论在慢性乙型肝炎患者中,ＨＧＶ混合感染对慢性乙型肝炎的病变程度及病毒复制无明显影响     

Hepatitis B virus infection and the risk of hepatocellular carcinoma

Epidemiological studies have provided overwhelming evidence for a causal role of chronic hepatitis B virus(HBV) infection in the development of hepatocellular carcinoma(HCC).However,the pathogenesis of HBV infection and carcinogenesis of HBV-associated HCC are still elusive.This review will summarize the current knowledge on the mechanisms involved in HBV-related liver carcinogenesis.The role of HBV in tumor formation appears to be complex,and may involve both direct and indirect mechanisms.Integration of H...     

Hepatitis B virus lineages in mammalian hosts:Potential for bidirectional cross-species transmission

The hepatitis B virus(HBV)is a cosmopolitan infectious agent currently affecting over 350 million people worldwide,presently accounting for more than two billion infections.In addition to man,other hepatitis virus strains infect species of several mammalian families of the Primates,Rodentia and Chiroptera orders,in addition to birds.The mounting evidence of HBV infection in African,Asian and neotropical primates draws attention to the potential crossspecies,zoonotic transmission of these viruses to man.Moreover,recent evidence also suggests the humans may also function as a source of viral infection to other mammals,particularly to domestic animals like poultry and swine.In this review,we list all evidence of HBV and HBVlike infection of nonhuman mammals and discuss their potential roles as donors or recipients of these viruses to humans and to other closely-related species.     

Hepatitis C virus eradication associated with hepatitis B virus superinfection and development of a hepatitis B virus specific T cell response

BACKGROUND/AIMS: Specific T cell responses during acute hepatitis B and during chronic hepatitis C have been described in detail. However, the T cell responses during the rare setting of acute hepatitis B virus (HBV) infection in the course of chronic hepatitis C that eventually lead to clearance of both viruses are completely unknown. METHODS: We analyzed the virus specific CD4+ and CD8+ T cell response during an acute HBV superinfection in a patient with chronic hepatitis C. RESULTS: The patient eliminated hepatitis C virus (HCV)-RNA and HBV-DNA from serum soon after the clinical onset of acute hepatitis B. The HBV specific T cell response found in this patient corresponds to the typical response that has been described in acute hepatitis B without chronic HCV infection. In contrast the hepatitis C specific immune response was similar to that generally found in chronic hepatitis C despite the fact that the patient also eliminated HCV-RNA. CONCLUSIONS: We hypothesize that the acute HBV infection induced a HBV specific T cell response which was associated with elimination HBV DNA and HCV-RNA, the latter possibly by bystander mechanisms, e.g. via secretion of cytokines. If such a non-specific bystander mechanism which has proven to be effective in the experimental setting and which is formally described here for a single patient can be shown to be a more general phenomenon, it may support the approach with new antiviral strategies, e.g. the induction of non-specific defense mechanisms against HCV.     

Hepatitis B virus genotypes in Europe

There are eight genotypes of hepatitis B virus (HBV). Most genotypes can be further divided into subgenotypes. HBV genotypes influence the course of disease and treatment, and show geographic preferences. In Europe, A and D are the main genotypes found. Genotype A is more prevalent in northern Europe, where genotype D is mainly found in countries surrounding the Mediterranean Sea and in Eastern Europe. Subgenotype A2 is the dominant subgenotype in Europe, but the geographic prevalence of the four subgenotypes found in genotype D is not yet clear. On treatment with interferon HBV, genotype A, compared to genotype D, showsbetter virological response and in a large proportion of patients, even development of anti-HBs. However, in the first year of treatment with lamivudine, higher rates of emergence of YMDD variants are observed in genotype A. This work summarizes the current knowledge on HBV genotypes in countries with low and intermediate HBV carriership from Europe.     

Long-Term Persistence of Seroprotection by Hepatitis B Vaccination in Healthcare Workers of Southern Italy

Background

The impact of hepatitis B virus (HBV) vaccination campaigns on HBV epidemiology needs to be evaluated, in order to assess the long-term immunity offered by vaccines against HBV.

Objectives

To evaluate the current status of anti-HBV vaccine coverage among healthcare workers (HCWs) in Southern Italy, and to determine the long-term persistence of antibodies to hepatitis B surface antigens (anti-HBs) in such a cohort of subjects.

Patients and Methods

A longitudinal, retrospective seroepidemiological survey was conducted among 451 HCWs, who were working at or visiting, the Occupational Health Department of a city hospital, in Catania, Italy, between January 1976 and December 2010.

Results

At the 30-year follow-up (mean follow-up 10.15 ± 5.96 years, range 0.74-30), 261 HCWs had detectable anti-HBs titers indicating a persistence of seroprotection of 89.4% (out of 292 anti-HBs positive results, three months after vaccination). An inadequate vaccination schedule was the strongest predictor of antibody loss during follow-up (OR = 8.37 95% CI: 5.41-12.95, P < 0.001). A Kaplan-Maier survival curve revealed that the persistence of anti-HBs 30 years after vaccination, was 92.2% for high responders, while it was only 27.3% for low responders (P = 0.001).

Conclusions

A good level of seroprotection persisted in 57.9% of the subjects after 30 years. Factors related to this immunization status confirmed the importance of vaccinating HCWs early in their careers and ensuring an adequate vaccination schedule. However, with particular reference to the low rate of hepatitis B vaccine coverage among HCWs in Southern Italy, the implementation of a new educational intervention as part of an active vaccination program is needed.