Pilot study to detect airborne Mycobacterium tuberculosis exposure in a South African public healthcare facility outpatient clinic

BACKGROUND : Airborne transmission of Mycobacterium tuberculosis (TB) remains an occupational health hazard particularly in crowded and resource limited healthcare settings. AIM : The study aimed to quantify airborne TB in a busy outpatient clinic in Gauteng, South Africa. METHODS : Personal (HCWs) and stationary air samples were collected in the Polyclinic and Administrative block. Quantitative real-time PCR was used to detect airborne TB. Walkthrough observations and work practices of HCWs were also recorded. FINDINGS : TB was detected in 11/49 (22.4%) of the 9/25 (36%) personal and 2/24 (8.3%) stationary samples. Samples from 5 of 10 doctors (50%) and 3 of 13 nurses (23%) were positive. Repeat measurements on different days showed variable results. Most of the HCWs (87.5%) with positive results had been in contact with coughing patients and had not worr respiratory masks despite been training. CONCLUSION : The use of air sampling coupled with real-time qPCR is a simple and effective tool to demonstrate the risk of TB exposure. The findings provide an impetus for hospital management to strengthen TB infection prevention and control measures.Canadian Institutes of Health Research (CIHR).http://www.elsevierhealth.com/journals/jhinhb2016School of Health Systems and Public Health (SHSPH

Occupational Risk of Airborne Mycobacterium tuberculosis Exposure: A Situational Analysis in a Three-Tier Public Healthcare System in South Africa

This study aimed to detect airborne Mycobacterium tuberculosis (MTB) at nine public health facilities in three provinces of South Africa and determine possible risk factors that may contribute to airborne transmission. Personal samples (n = 264) and stationary samples (n = 327) were collected from perceived high-risk areas in district, primary health clinics (PHCs) and TB facilities. Quantitative real-time (RT) polymerase chain reaction (PCR) was used for TB analysis. Walkabout observations and work practices through the infection prevention and control (IPC) questionnaire were documented. Statistical analysis was carried out using Stata version 15.2 software. Airborne MTB was detected in 2.2% of samples (13/572), and 97.8% were negative. District hospitals and Western Cape province had the most TB-positive samples and identified risk areas included medical wards, casualty, and TB wards. MTB-positive samples were not detected in PHCs and during the summer season. All facilities reported training healthcare workers (HCWs) on TB IPC. The risk factors for airborne MTB included province, type of facility, area or section, season, lack of UVGI, and ineffective ventilation. Environmental monitoring, PCR, IPC questionnaire, and walkabout observations can estimate the risk of TB transmission in various settings. These findings can be used to inform management and staff to improve the TB IPC programmes