Risk assessment of tuberculosis laboratories and biosafety practices among laboratory health workers in two selected states in Nigeria

Abstract

Background: Occupational tuberculosis among mycobacteriology laboratory workers has received insufficient attention especially in countries with high burden of tuberculosis despite the associated greater risk than the general population. The aim of the study was to conduct a risk assessment of tuberculosis (TB) laboratories and biosafety Practices among laboratory health workers.

Method: A descriptive study conducted among the laboratory health workers involved primarily in the diagnosis of tuberculosis (TB) in two selected states in Nigeria. A semi-structured questionnaire based on tuberculosis laboratory procedure risk assessment was self-administered by consenting laboratory workers. Data obtained were based on the degree of exposure, viability of bacilli, aerosol generation, laboratory configuration, typology and fitness of the staff to work in the TB laboratory. Risk assessment of tuberculosis (TB)laboratories and biosafety practices was determined by these sets of questions and categorized into low, middle and high risk.

Results: Fifty-eight (58) of the 64 laboratory health workers participated in the study. Their average age was 38.8±7.6 years and male to female ratio of 1 to 1.4 and 82.7% had worked in the TB laboratory for  less than 10 years. The calculated risk for occupational TB was low 55(94.8%) and moderate 3(5.2%) without any of the respondents having high risk. With regards to laboratory practices, majority of the respondents (91.4%) did not reuse slides for smear staining, 81.0% admitted that the laboratories were well-ventilated and75% regarded their laboratories safe to work. However, preemployment screening for TB, HIV, diabetes mellitus, and kidney disease was done in 3(5.2%), 7(12.1%), 2(3.4%) and 1(1.7%) respectively.

Conclusion: The result of this study shows that the risk of laboratory health workers exposure to tuberculosis (TB) and potential hazard is low, however moreattention be given to infection control policies and pre-employment screening for TB.