Enhanced screening and preventive therapy for TB in Daru, South Fly District, Papua New Guinea

Tuberculosis (TB) is a curable disease but remains the leading infectious disease killer in the world with 1.4 million lives lost in in 2015. In addition to the human cost, TB has extraordinary social and economic impacts. The emergence and spread of drug-resistant TB (DR-TB) is a threat to global health security and it is more complex, challenging and costly than responding to DS-TB. The United Nations Sustainable Development Goals (SDGs) aim to end the global TB epidemic by 2030. The current strategy of detecting and treating people with active TB alone, will not achieve this ambitious goal alone. Strategies that can also prevent people with TB infection from developing TB, including DR-TB – as happens in low TB burden countries such as Australia – needs to be implemented and evaluated in high burden settings, and are potentially very cost-effective.

Daru Island (population of 20 000) in South Fly District (SFD), Papua New Guinea is the epicentre of an outbreak of TB and more alarmingly, drug-resistant TB (DR-TB) with rates that are among the highest recorded globally in a low-HIV setting. Person to person spread of DR-TB is occurring in over-crowded households. Concerning transmission of extensively drug-resistant TB (XDR-TB) has already been reported. Burnet modeling studies suggest that 88% of the Island population has a TB infection (latent TB). Children under 5 are a recognised “high risk” group for progressing from infection to active TB. Preventive therapy with anti-TB drugs is effective to stop this progression for drug-susceptible TB, including shorter regimens and evidence is emerging for strategies in DR-TB.

To combat the TB outbreak in Daru and the country’s epidemic, a comprehensive strategy consisting of actively searching for all cases, linking them to effective treatment and treating TB infection (preventive therapy) is needed to reduce transmission. However, there are few operational models demonstrating how this can be done in low and middle-income countries and none in PNG.