Implementation of large-scale pooled testing to increase rapid molecular diagnostic test coverage for tuberculosis: a retrospective evaluation

In 2021, only 6.4 million of the 10.6 million people with tuberculosis (TB) were diagnosed and treated for the disease. Although the World Health Organization recommends initial diagnostic testing using a rapid sensitive molecular assay, only 38% of people diagnosed with TB benefited from these, due to barriers including the high cost of available assays. Pooled testing has been used as an approach to increase testing efficiency in many resource-constrained situations, such as the COVID-19 pandemic, but it has not yet been widely adopted for TB diagnostic testing. Here we report a retrospective analysis of routine pooled testing of 10,117 sputum specimens using the Xpert MTB/RIF and Xpert MTB/RIF Ultra assays that was performed from July 2020 to February 2022. Pooled testing saved 48% of assays and enabled rapid molecular testing for 4156 additional people as compared to individual testing, with 6.6% of specimens positive for TB. From an in silico analysis, the positive percent agreement of pooled testing in pools of 3 as compared with individual testing for the Xpert MTB/RIF Ultra assay was estimated as 99.4% (95% CI, 96.6% to 100%). These results support the scale-up of pooled testing for efficient TB diagnosis.

Knowledge, attitude and prevalence of hepatitis B virus among healthcare workers: a cross-sectional, hospital-based study in Bamenda Health District, NWR, Cameroon

INTRODUCTION

Hepatitis B virus (HBV) is a bloodborne virus which can be transmitted via percutaneous and mucocutaneous exposure to infected body fluid. Healthcare workers (HCWs) who are continuously exposed to different body fluids are at an increased risk of contracting and transmitting this virus. It is thus important to evaluate the knowledge and attitude of HCWs towards HBV and the prevalence of HBV infection among them.

METHODS

This cross-sectional study was carried out between April and September 2017. Overall, 398 HCWs were recruited for this study. Knowledge on the route of HBV transmission and attitude towards HBV were evaluated using a well-structured questionnaire. Hepatitis B surface antigen (HBsAg) positivity was obtained using the Monolisa HBsAg ULTRA kit (Bio-Rad). Data were analysed using SPSS V.20.

RESULTS

Among the HCWs who participated in this study, 338 (84.9%) had heard of HBV, and 269 (67.6%) of them had adequate knowledge on the route of HBV transmission. Medical doctors were the most knowledgeable among biomedical workers and students (76.5%). The rate of stigma was highest among nurses (87, 38.8%). The prevalence of HBsAg positivity was high (42, 10.6%) given that there is an efficient and available vaccine. Overall, over 70% of HCWs invited to participate in this study responded.

CONCLUSION

Knowledge on the route of HBV transmission was fair, and the level of stigmatisation of HBV-infected patients and the prevalence of HBV infection were high in this study. A sensitisation campaign should be carried out to educate HCWs on HBV, thus reducing the level of stigma associated with HBV as well as the probability of contracting HBV as a nosocomial infection.