Estimated numbers of new TB cases in Patan, a city in Nepal

Purpose – The purpose of the paper is to show that, despite comprehensive coverage of services for TB provided by a public‐private partnership for TB control in Patan, a city in Nepal, case finding is low, compared with the target based on an Annual Risk of Tuberculosis Infection (ARTI) of 4 per cent. Doubts have been raised as to the appropriateness of the target. The objective of the study was to estimate the number of new TB cases occurring in Patan, to assess whether the target was appropriate. Design/methodology/approach – In the paper doorstep interviews were conducted with all households in the study area, followed by in‐depth interviews of households with possible or probable TB cases. The survey findings were validated against the patient registers of the five DOTS centres in Patan. Findings – The paper finds that, among the study population of 36,918, the household survey identified 17 smear‐positive TB cases (none privately‐treated) and 24 smear‐negative/extra‐pulmonary cases (including four privately‐treated cases). Validation against the DOTS patient registers indicated that the survey was 54 per cent complete. After adjusting for incompleteness, the number of smear‐positive cases in the study area was estimated as 31, equivalent to an incidence of 85 smear positives per 100,000 population and an ARTI of 1.7 per cent. Originality/value – The paper shows that using the ARTI may lead to misleadingly high targets for urban TB control. Unrealistically high targets may cause TB workers to become demoralised, and useful strategies to be abandoned. Therefore, further work is needed to identify better ways of setting targets.