Effectiveness of Tuberculosis Screening to Detect Active Tuberculosis and Prevent Workplace Transmission Among Workers in Congregate Living Settings in Papua New Guinea

Abstract Objectives/Scope The World Health Organization (WHO) has classified Papua New Guinea (PNG) as a high tuberculosis (TB)-burden country; therefore, the risk for TB infections among camp residents is high. ExxonMobil PNG (EMPNG) implemented a TB screening program using the QuantiFERON-G (QFT-G) screening method. The objective of this paper is to study the effectiveness of detecting and preventing the transmission of active TB at the EMPNG work sites in PNG. Methods, Procedures, Process The EMPNG TB screening program requires annual TB screening for these individuals: a) All workers who live and work at a remote camp for 30 days or more per year. b) Visitors to remote sites who will work and live on sites for more than 30 days a year. Project health workers monitor individuals who test positive for active or latent TB, since the QFT-G test does not determine the TB status of a person. Individuals with active TB are quarantined and referred for treatment. Those with latent TB (LTBI) must have annual reviews at the site clinic. Results, Observations, Conclusions A review of the data over a 10-year period identified 23% percent of individuals with LTBI; all these individuals were placed in a latent TB register and monitored closely in the event they convert to active TB. They were all required to undergo annual medical examinations and were told to report to the clinic if they developed any respiratory symptoms. Of the 57 personnel who converted to active TB within three years, 30 were detected as part of the annual LTBI monitoring program. While QFT-G TB screening was helpful in identifying those with LTBI, its role was limited in the detection of active TB at the time of screening. All those diagnosed with active TB in the workplace were symptomatic individuals who visited the site clinic because they were unwell or were symptomatic individuals who had progressed from LTBI to active TB and were under the LTBI monitoring program. There was no recorded workplace transmission of TB from individuals with active TB, with early reporting a possible contributing factor. The disease progression rate from LTBI to active TB was 1.2%. This percentage is slightly lower than data published by the WHO and the U.S. Centers for Disease Control and Prevention. By actively monitoring those on the LTBI register, we were able to ensure that individuals sought medical attention as soon as they developed symptoms. Novel/Additive Information There is no standard guidance on a TB screening program for workers in congregate living settings in the oil and gas industry. While the TB screening program at the EMPNG work sites did not detect active TB during screening, it detected latent TB cases who were monitored closely in the event they convert to active TB. Any TB screening program should complement other components of a TB control program which are awareness/ training and early detection and diagnosis.