Contact tracing in pulmonary and non-pulmonary tuberculosis

Aim: The aim of our study was to determine the effectiveness of contact tracing for both pulmonary and non-pulmonary tuberculosis (TB). Methods: The authors studied contact tracing in South East of Scotland, Edinburgh TB Clinic, UK, for 3 years. New index cases of both pulmonary and non-pulmonary TB were identified from reviewing TB nurses records. Pulmonary involvement was excluded from all non-pulmonary cases. Active TB was diagnosed as per the national TB guidelines. Latent TB was diagnosed based on history, tuberculin skin test and interferon gamma release assay. TB contacts were identified from reviewing TB nurses notes on index TB patients. A positive screening episode was defined as identification of either active or latent TB in a contact following relevant investigations. Results: Total number of positive screening episodes for pulmonary TB was 43.1% and non-pulmonary TB was 26.1%. Of these, 78.8% were household contacts and 21.2% were casual contacts. Conclusion: Contact tracing in low-prevalence TB countries, for both pulmonary and non-pulmonary TB, is an essential intervention to identify and reduce the number of infected patients that will progress to active disease. This is the key for effective TB control.