High prevalence of pulmonary tuberculosis among female sex workers, men who have sex with men, and transgender women in Papua New Guinea

Background: Papua New Guinea (PNG) has a tuberculosis (TB) case notification rate of 333 cases per 100,000 population in 2016 and is one of the 14 countries classified by the World Health Organization (WHO) as "high-burden" for TB, multi-drug-resistant TB (MDR-TB), and TB/HIV. HIV epidemic is mixed with a higher prevalence among key populations, female sex workers (FSW), men who have sex with men (MSM), and transgender women (TGW).

Methods: We conducted a cross-sectional HIV biobehavioral survey (BBS) using respondent-driven sampling method among FSW, MSM, and TGW in Port Moresby, Lae, and Mt. Hagen (2016-2017). As part of the study, participants were screened for the four symptoms suggestive of TB infection using the WHO TB screening algorithm. Sputum and venous whole blood samples were collected and tested for pulmonary TB and HIV infection, respectively. Pulmonary TB testing was performed using GeneXpert®MTB/RIF molecular point-of-care test, and HIV testing was done following the PNG national HIV testing algorithm. All data discussed are weighted unless otherwise mentioned.

Results: Among FSW, 72.6%, 52.0%, and 52.9% in Port Moresby, Lae, and Mt. Hagen, respectively, experienced at least one symptom suggestive of TB infection. Among MSM and TGW, 69% and 52.6% in Port Moresby and Lae, respectively, experienced at least one symptom suggestive of TB infection. Based on GeneXpert®MTB/RIF results, the estimated TB prevalence rate among FSW was 1200, 700, and 200 per 100,000 in Port Moresby, Lae, and Mt. Hagen, respectively. Among MSM and TGW, the estimated TB prevalence rate was 1000 and 1200 per 100,000 in Port Moresby and Lae, respectively. Co-prevalence of TB/HIV among FSW was 0.1% in Port Moresby and 0.2% in Lae. There were no co-prevalent cases among FSW in Mt. Hagen or among MSM and TGW in Port Moresby and Lae.

Conclusions: Key populations have a higher estimated rate of pulmonary TB than the national rate of pulmonary and extra-pulmonary TB combined. This showed that screening key populations for TB should be integrated into HIV programs regardless of HIV status in PNG's national TB response.