Background: Philippines, Indonesia, and Bangladesh are three high tuberculosis (TB) burden countries in Asia which account for 18% of the estimated global TB incidence (1.8 million) and 15% of TB related deaths (192,000). In 2017 alone, approximately 785,000 of the incident TB cases in these countries remained missing, including diagnosed but not notified.
Methods: We reviewed the published data from the most recent TB prevalence surveys conducted in Bangladesh, Indonesia, and the Philippines. The prevalence rates established by the surveys were used to estimate the disease burden of these countries for 2017. The Global TB Report 2017 and World Health Organization's (WHO) global TB database were sourced for collection of incidence and notification data by age groups and types of TB to estimate prevalence to notification gaps 2017.
Results: According to the surveys, the estimated prevalence rates of bacteriologically confirmed TB and smear-positive TB are 287 and 113 for Bangladesh (2015-16), 759 and 256 for Indonesia (2013-14) and 1159 and 434 for the Philippines (2016) per 100,000 population over the age of 15 years. The overall national TB prevalence estimates for all forms is 260 for Bangladesh, 660 for Indonesia, and 970 for the Philippines (2016). Compared with the incidence rate, the proportion of total notified cases is 67% for Bangladesh, 52% for Indonesia, and 55% for the Philippines. Bangladesh has been able to detect almost 100% of the prevalent pulmonary TB, while Indonesia and Philippines have detected only 30 and 22% of these infectious cases respectively. Although notification has been improving over the years, there is no impact on the incidence rate since a large proportion of the undiagnosed cases, and delayed diagnosis continue to feed the transmission process.
Conclusion: The surveys have provided data that is critical for developing realistic strategies for these countries to eliminate TB. In general, this paper recommends interventions for strengthening diagnosis of pulmonary TB, implementing targeted communication programs and active case finding to reduce patient level delays, expanding public-private partnership to increase access to TB services, using rapid diagnostics, and providing social protection for vulnerable populations. These measures can accelerate these countries' progress towards achieving End TB goals.
Keywords: End TB; Incidence; Prevalence; Tuberculosis.