Hepatitis B vaccination policies for health‐care workers: Need for a worldwide consensus

Abstract

Dear Editor, In a recent report in this journal presented by Komatsu et al., the differences in the hepatitis B (HB) vaccination policies for health‐care workers (HCWs) among three countries were presented. A discordance about the protective anti‐HB surface antibody (anti‐HBs) threshold level, and if or when to recommend a booster dose or doses of HB vaccine after a primary course of vaccination, was found. These differences in the recommendations unfortunately create confusion for the management of HCWs. I would like to make some comments on this paper. Increasing the HB vaccination coverage among HCWs, mandatory or recommended, is a challenge worldwide. Since 2000, under the European Union legislation, employers are responsible for protecting their HCWs against hepatitis B virus (HBV) infection. Recently, Maltezou et al. (2019) and De Schryver et al. (2020) published updates on vaccination policies for European HCWs. Maltezou et al. reported that 15 countries recommended HB vaccination for HCWs and eight countries had mandatory policies in 2018. De Schryver et al. published an overview of their electronic survey of HB vaccination policies for HCWs. The updates were deemed necessary in view of the introduction of universal HBV vaccination programs. It seemed that the way different countries dealt with the European Union legislation regarding HB vaccination has not been adjusted drastically since the first survey in 2006/2007. These surveys illustrated (again) the strong country‐to‐country variation, for example, regarding the umbrella term “HCWs”, prevaccination and postvaccination serological testing, anti‐HBs threshold, vaccination schedules, types of vaccines, policy on low and non‐responders, and booster policy. The persistence of immunogenicity after HB vaccination is still a matter of debate. Studies with up to 30‐year follow‐up demonstrated high rates of anamnestic response to booster doses, even when detectable antibodies were absent at the time of exposure. Although, disappearing of a rapid anamnestic response (“boostability loss”) has been found in studies in Asia. The Steering Committee for the Prevention and Control of Infectious Diseases in Asia has put forward guidelines recommending that administering boosters to HCWs should be a selective decision, depending on the endemicity of the particular country in question. Based on studies in Thailand and Italy, Komatsu et al. concluded that booster vaccination might be required for HCWs who are at high risk of exposure to HBV and young HCWs who were immunized at birth or at a young age. Many HCWs may have received their primary HBV vaccine series over 20–25 years ago. But a drop in anti‐HBs below the value of 10, or less than 100 mIU/ml, does not necessarily mean susceptibility to HBV infection. Furthermore, the Cochrane database systematic review from 2016 concluded that there is no scientific evidence to support or reject the need for booster doses of HB vaccine in healthy individuals with normal immune status. The immunological memory decades after immunization needs further investigation. Definitely, more research is needed on the vaccination strategies (including serotesting) for (student) HCWs already vaccinated as an infant, child, or adolescent. Implementation of a universal policy or guideline on HB vaccination of HCWs based on an evidence‐based consensus is needed.