Abstract
BackgroundIn the Republic of Korea (ROK), compared to other high-income countries, tuberculosis (TB) prevalence is relatively high. Active TB and latent TB infection (LTBI) surveillance of individuals living in TB-affected households has been conducted for several years. Although active case finding is an important strategy in low-prevalence, high-income countries, its effectiveness in a high prevalence setting is unclear. This study evaluated the risk of TB in household contact by calculating the incidence of TB among household contacts and comparing it with the general population of the ROK.MethodsA retrospective cohort study, including 36,133 household-contacts of 17,958 TB patients reported in 2015, was conducted. The data was extracted from the Korean National TB Surveillance System (web-based TB cases notification system, KNTSS). The Cox proportional hazard regression model was used to evaluate risk factors for incidence of TB. A P-value < .05 was considered statistically significant.ResultsIn this study, 319 (0.9%) of 36,133 household-contacts were reported as having TB within 1 year, which is a higher rate than the rate for the general population in the ROK. The rate of TB reported for contacts that had completed LTBI treatment (0.6%) was lower than for the LTBI group without treatment (4.6%). In multivariate analysis, age older than 65 (p < .001), being a spouse of a TB patient (p = .007), and LTBI without treatment (p = .013) were each a risk factor for TB incidence among contacts. Younger age (p < .001), presence of a cough (p < .001), testing positive for acid-fast bacilli (AFB; p < .001), and cavity on radiograph (p < .001) of the index patient were also statistically significant risk factors.ConclusionsIndividuals living in TB-affected households are at high risk of developing TB in the ROK and active case finding among them is a strategy effective in the early detection and prevention of TB.
Highlights
Tuberculosis (TB) is an infectious disease caused by bacteria (Mycobacterium tuberculosis)
This study evaluated the risk of TB in household contact by calculating the incidence of TB among household contacts and comparing it with the general population of the Republic of Korea (ROK)
319 (0.9%) of 36,133 household-contacts were reported as having TB within 1 year, which is a higher rate than the rate for the general population in the ROK
Summary
Tuberculosis (TB) is an infectious disease caused by bacteria (Mycobacterium tuberculosis). Other previous studies have evaluated the effect of household contact investigation on decrease the prevalence of TB. A randomized comparative study conducted in Vietnam found that the detection rate of TB in the group that the household contact investigation was conducted, was higher than the group with the passive case finding alone among household contacts during 2-year period [5, 6]. The effect of active case finding strategy among household contacts on TB incidence remains subject to debate. Active case finding is an important strategy in low-prevalence, high-income countries, its effectiveness in a high prevalence setting is unclear.
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
