Latent tuberculosis prevalence in healthcare workers in Laos: a cross-sectional study

Background: Individuals with latent tuberculosis infection (LTBI) have a high risk of active infection, morbidity and mortality. Healthcare workers are a group who have increased risk of infection and onward transmission to their patients and other susceptible individuals; however, LTBI is often undiagnosed, and individuals are asymptomatic. Interferon gamma release assays (IGRA) can detect evidence of TB infection in otherwise asymptomatic individuals and are a good indication of LTBI. Laos, a resource limited country in southeast Asia, has limited data on TB prevalence in the general population or in healthcare workers. This study aimed to estimate the prevalence of LTBI in Lao healthcare workers in Vientiane Capital.

Methods: Healthcare workers from high-risk departments from 3 central hospitals in Laos were included (n = 196) and venous blood was tested by IGRA. A questionnaire was administered to determine their knowledge, attitude and practice towards TB and LTBI.

Results: 10.2% of the participants were positive by IGRA, none of whom were previously aware of their TB status. The questionnaire revealed that knowledge and awareness of TB and LTBI were low.

Discussion: A significant proportion of healthcare workers in this study had evidence of LTBI infection. These individuals were unaware of their TB status and we suggest that testing and treatment, as well as prevention strategies, should be routinely administered in Lao hospitals.