Immunity Gaps Exist for Hepatitis B Virus Among Healthcare Workers in Timor-Leste

Published on: 

The majority of healthcare workers included in the study were immune to both measles and rubella.

Despite a high risk of exposure of hepatitis B virus (HBV), healthcare workers often remain unprotected from the virus in Timor-Leste1.

A team, led by Celia Gusmao, Hospital Nacional Guido Valadares, determined the seroprevalence of hepatitis B, measles, and rubella among healthcare workers in Dili, Timor-Leste.

WHO Guidelines

The World Health Organization (WHO) currently recommends healthcare workers vaccinate against measles and rubella and if they are at a high risk of exposure hepatitis B.

However, there is no formal program for occupational assessment and provision for vaccination in Timor-Leste for healthcare workers.

In the cross-sectional study, the investigators examined all patient-facing employees at 3 healthcare institutions between April and June 2021 and collected epidemiological data using an interview questionnaire and collected serum samples by phlebotomy. The data was analyzed at the National Health Laboratory.

Data Collection

Each sample was analyzed for rubella IgG (quantitative, positive if >10 IU/mL) hepatitis B surface antigen (HBsAg, qualitative), hepatitis B core total (IgG and IgM) antibody (HBcAb, qualitative), and hepatitis B surface antibody (HBsAb, positive if >10 mIU/mL).

Each participant was contacted and asked to discuss their results and offered relevant vaccines if they were a seronegative individuals. Participants with active HBV infections were referred for further assessment and management in a hepatology clinic.

Overall, there were 324 healthcare workers included in the analysis, representing 51.3% of all eligible healthcare workers at the 3 participating institutions with a median age of 29 years.

Of this group, 4.9% (n = 16; 95% Confidence Interval (CI), 2.8-7.9%) had active HBV infections. In addition, 37.3% (n = 121; 95% CI, 32.1-42.9%) had of evidence of a previous HBV infection that was cleared and 41.4% (n = 134; 95% CI 35.9-46.9%) were hepatitis B seronegative. Finally, 16.4% (n = 53; 95% CI, 12.5-20.8%) had been vaccinated.

In the measles and rubella analysis, 82.4% (n = 267; 95% CI, 77.8-86.4%) of the participants showed antibodies to measles, while 94.4% (n = 306; 95% CI, 91.4-96.7%) individuals exhibited antibodies for rubella.

Of the participants with active HBV infections, 68.8% (n = 11) did not report a prior diagnosis before the study. Specifically, 25% (n = 4) were HBeAg positive and 75% (n = 12) were HBeAG negative.

Conclusion and Limitations

“There are significant immunity gaps and a high prevalence of hepatitis B infection among HCWs in Dili Municipality, Timor-Leste,” the authors wrote. “Routine occupational assessment and targeted vaccination of this group would be beneficial and should include all types of HCWs. This study provided an opportunity to develop a programme for the occupational assessment and vaccination of HCWs and forms the template for a national guideline.”

There were some limitations in the study. First, the patient size was relatively small and from only 3 healthcare institutions in 1 municipality. Another potential limitation is the generalizability is reduced in the findings.

“It is possible that access/uptake of vaccination among HCWs has been higher in Dili than the rest of Timor-Leste, because healthcare infrastructure is relatively developed and there has been more consistent access to medicines,” the authors wrote. “Similarly, occupational exposure of HCWs to pathogens may be reduced because personal protective equipment is more readily available.”


Gusmao C, Tanesi MY, Gomes N, et al. Seroprevalence and prevention of hepatitis B, measles and rubella among healthcare workers in Dili, timor-leste. The Lancet Regional Health - Southeast Asia. 2023:100133. doi:10.1016/j.lansea.2022.100133