Contact investigation (CI) is the systematic evaluation of individuals in close contact with an infectious tuberculosis (TB) case, i.e., a person with a bacilloscopically confirmed (BK+) or clinically diagnosed pulmonary TB index case. CI is one of the key global strategies for active case finding (ACF) of persons with TB disease to ensure treatment and for early detection of TB cases so as to prevent progression to TB disease through timely provision of TB preventive treatment (TPT). Monitoring the cascade of CI indicators provides an opportunity to track the yield of CI, prevent pre-treatment case loss, reduce the number of underreported and underdiagnosed TB cases, plan for program improvement, and conduct routine continuous quality improvement (CQI) to the CI activities.
Looking at Data
Take a look at the data in your country using the following charts and their descriptions. Share your insights with hub@tbdiah.org.
New and Relapse Pulmonary TB Cases
This chart provides the context in terms of total number of people notified for pulmonary TB, disaggregated by bacilloscopically confirmed (BK+) and clinically diagnosed, who ideally are candidates for contact investigation.
Contacts of Bacilloscopically Confirmed TB Cases
This second graph compares the estimated number of contacts of bacilloscopically confirmed (BK+) pulmonary TB cases with the number of such contacts reported by the country and the number of contacts who were investigated for TB. The estimated number of contacts is calculated using the average household size and the number of BK+ pulmonary TB cases reported in a given year (formula using WHO variables: ((new_labconf + ret_rel_labconf) * e_hh_size)).
Contact Investigation & TB Preventive Treatment
This third section shows the sequential steps in CI and TPT, starting from the number of household contacts reported by the country, the number who were screened/evaluated for TB, the number who started TPT, and the number who completed TPT. A breakdown of contacts by age groups (under-5 and 5 years and older) is also included in the tabs immediately above the chart.
Proportion of contacts who were screened and put on TPT
This chart provides the visual of the proportion of household contacts who were screened and those who were put on TPT.