Projecting the impact of variable MDR-TB transmission efficiency on long-term epidemic trends in South Africa and Vietnam.

Whether multidrug-resistant tuberculosis (MDR-TB) is less transmissible than drug-susceptible (DS-)TB on a population level is uncertain. Even in the absence of a genetic fitness cost, the transmission potential of individuals with MDR-TB may vary by infectiousness, frequency of contact, or duration of disease. We used a compartmental model to project the progression of MDR-TB epidemics in South Africa and Vietnam under alternative assumptions about the relative transmission efficiency of MDR-TB. Specifically, we considered three scenarios: consistently lower transmission efficiency for MDR-TB than for DS-TB; equal transmission efficiency; and an initial deficit in the transmission efficiency of MDR-TB that closes over time. We calibrated these scenarios with data from drug resistance surveys and projected epidemic trends to 2040. The incidence of MDR-TB was projected to expand in most scenarios, but the degree of expansion depended greatly on the future transmission efficiency of MDR-TB. For example, by 2040, we projected absolute MDR-TB incidence to account for 5% (IQR: 4-9%) of incident TB in South Africa and 14% (IQR: 9-26%) in Vietnam assuming consistently lower MDR-TB transmission efficiency, versus 15% (IQR: 8-27%)and 41% (IQR: 23-62%), respectively, assuming shrinking transmission efficiency deficits. Given future uncertainty, specific responses to halt MDR-TB transmission should be prioritized.

Conducting Patient-Pathway Analysis to Inform Programming of Tuberculosis Services: Methods.

Patient-centered care is a central pillar of the World Health Organization's End TB Strategy. Understanding where patients access health services is a first step to planning for the placement of services to meet patient needs and preferences. The patient-pathway analysis (PPA) methodology detailed in this article was developed to better understand the alignment between patient care seeking and tuberculosis service availability. A PPA describes the steps that people with tuberculosis take from the initial care visit to cure. The results of a PPA reveal programmatic gaps in care seeking, diagnosis, treatment initiation, and continuity of care. They can be used as inputs to an evidence-based process of identifying and developing interventions to address the gaps in patient care. This paper summarizes the steps to conduct a PPA and serves as the basis for understanding country case studies that profile the use of PPA.

Finding the Missing Patients With Tuberculosis: Lessons Learned From Patient-Pathway Analyses in 5 Countries.

Background: Despite significant progress in diagnosis and treatment of tuberculosis over the past 2 decades, millions of patients with tuberculosis go unreported every year. The patient-pathway analysis (PPA) is designed to assess the alignment between tuberculosis care-seeking patterns and the availability of tuberculosis services. The PPA can help programs understand where they might find the missing patients with tuberculosis. Methods: This analysis aggregates and compares the PPAs from case studies in Kenya, Ethiopia, Indonesia, the Philippines, and Pakistan. Results: Across the 5 countries, 24% of patients with tuberculosis initiated care seeking in a facility with tuberculosis diagnostic capacity. Forty-two percent of patients sought care at level 0 facilities, where there was generally no tuberculosis diagnostic capacity; another 42% of patients sought care at level 1 facilities, of which 39% had diagnostic capacity. Sixty-six percent of patients initially sought care in private facilities, which had considerably less tuberculosis diagnostic capacity than public facilities; only 7% of notified cases were from the private sector. The GeneXpert system was available in 14%-41% of level 2 facilities in the 3 countries for which there were data. Tuberculosis treatment capacity tracked closely with the availability of diagnostic capacity. There were substantial subnational differences in care-seeking patterns and service availability. Discussion: The PPA can be a valuable planning and programming tool to ensure that diagnostic and treatment services are available to patients where they seek care. Patient-centered care will require closing the diagnostic gap and engaging the private sector. Extensive subnational differences in patient pathways to care call for differentiated approaches to patient-centered care.