Ayinalem Alemu, Getachew Seid, Adamu Tayachew, Yimam Getaneh, Negga Asamene, Gemechu Tadesse, Zebenay Workneh Bitew
About half of TB cases among HHCs were asymptomatic, highlighting the need for integrated TB screening beyond symptoms to improve early detection and reduce transmission.
OBJECTIVE: To estimate the prevalence of asymptomatic tuberculosis (TB) among household contacts (HHC) of active pulmonary TB cases.
METHODS: This study followed the PRISMA guidelines and was registered in PROSPERO (CRD420261302883). We searched electronic databases and grey literature sources for studies published up to April 18, 2026. Studies were screened, and quality was assessed using the Joanna Briggs Institute tools. Data were analyzed using STATA version 17, and pooled values were estimated along with 95%CIs. Heterogeneity was assessed using I², and publication bias using funnel plots, Egger's test, and trim-and-fill analysis where appropriate.
RESULTS: Of the 14,885 articles searched, 18 studies conducted in 12 countries involving 46,480 participants (HHCs) were included. The pooled prevalence of TB among asymptomatic HHCs was 4.0% (95%CI: 2.1-5.8%). Asymptomatic TB accounted for 51.0% (95%CI: 39.7-62.2%) of all identified TB cases. An estimated 2% (95%CI: 0.7-3.2%; I²: 90.67%) of TB-free asymptomatic contacts at baseline developed TB during follow-up. Male sex, chest X-ray suggestive of TB, cigarette smoking, and being a drug user were associated with asymptomatic TB.
CONCLUSION: About half of TB cases among HHCs were asymptomatic, highlighting the need for integrated TB screening beyond symptoms to improve early detection and reduce transmission.