Revisiting tuberculosis risk in Peace Corps Volunteers, 2006-13.

Background: Risk of tuberculosis (TB) is generally considered to be low for long-term travellers, though risk varies with travel destination, duration and purpose. Peace Corps Volunteers (PCVs) serve for 27 months as community-level development workers in various countries around the world and may be exposed to TB in the course of their service. This study examines recent trends in TB in PCVs and compares rates with a previous analysis published by Jung and Banks.

Methods: Tuberculosis case data submitted to the Peace Corps' Epidemiologic Surveillance System by Peace Corps Medical Officers and gathered from Federal Employees Compensation Act claims for latent TB infection (LTBI) and active TB between 2006 and 2013 were aggregated and analysed for trends and significance.

Results: Overall, there were 689 cases of LTBI and 13 cases of active TB, for a rate of 0.95 cases of LTBI [95% confidence interval (CI) 0.88-1.02] and 0.02 cases of active TB (95% CI 0.01-0.03) per 1000 Volunteer-months. Both are significantly lower than rates presented in the initial study (P < 0.001). Per-country incidence rates for LTBI ranged from 0.00 to 4.52 cases per 1000 Volunteer-months. Per-country active TB rates ranged from 0.00 to 0.78 cases per 1000 Volunteer-months. Among the 13 cases of active TB, there was one successfully treated case of extensively drug-resistant TB.

Conclusions: Overall rates of both active and latent TB in PCVs were significantly lower compared with the previous study period. PCVs continue to have statistically significantly higher rates of active TB compared with the general US population but lower rates compared with other long-term travellers.