Strategies to detect and manage latent tuberculosis infection among household contacts of pulmonary TB patients in high TB burden countries ‐ a systematic review and meta‐analysis

Abstract

Objective To summarise latent tuberculosis infection (LTBI) management strategies among household contacts of bacteriologically confirmed pulmonary tuberculosis (TB) patients in high‐TB burden countries. Methods PubMed/MEDLINE (NCBI) and Scopus were searched (January 2006 to December 2021) for studies reporting primary data on LTBI management. Study selection, data management and data synthesis were protocol‐driven (PROSPERO‐CRD42021208715). Primary outcomes were the proportions of LTBI, initiating and completing tuberculosis preventive treatment (TPT). Reported factors influencing the LTBI care cascade were qualitatively synthesised. Results From 3694 unique records retrieved, 58 studies from 23 countries were included. Most identified contacts were screened (median 99%, interquartile range [IQR] 82%–100%; 46 studies). Random‐effects meta‐analysis yielded pooled proportions for: LTBI 41% (95% confidence interval [CI] 33%–49%; 21,566 tested contacts); TPT initiation 91% (95% CI 79%–97%; 129,573 eligible contacts, 34 studies); TPT completion 65% (95% CI 54%–74%; 108,679 TPT‐initiated contacts, 28 studies). Heterogeneity was significant (I2 ≥ 95%–100%) and could not be explained in subgroup analyses. Median proportions (IQR) were: LTBI 44% (28%–59%); TPT initiation 86% (60%–100%); TPT completion 68% (44%–82%). Nine broad themes related to diagnostic testing, health system structure and functions, risk perception, documentation and adherence were considered likely to influence the LTBI care cascade. Conclusion The proportions of household contacts screened, detected with LTBI and initiated on TPT, though variable was high, but the proportions completing TPT were lower indicating current strategies used for LTBI management in high TB burden countries are not sufficient.

Test and Treat Model for Tuberculosis Preventive Treatment among Household Contacts of Pulmonary Tuberculosis Patients in Selected Districts of Maharashtra: A Mixed-Methods Study on Care Cascade, Timeliness, and Early Implementation Challenges

“…The prevalence of TBI in our study was 22.9%, which is a little less than the pooled prevalence of positive tests for TBI found across studies conducted in low-and middleincome countries (LMICs), which ranges from 41 to 69% [8,[11][12][13][14]. This difference may be attributed to specific factors, including the inclusion of only HHCs of PTB patients (both microbiologically and clinically confirmed) and not of high-risk groups, and use of only IGRA, not TST.…”

“…Of the HHCs with TBI, one-eighth dropped out before undergoing a chest X-ray and medical assessment. This could have been due to X-ray accessibility issues (time, distance, and transport), the need for multiple or repeated visits, loss of work hours, perceived lower risk of disease, and poor awareness of the disease and TPT among HHCs and their family members [ 11 , 13 , 17 ]. Despite these dropouts, all eligible HHCs were started on TPT after the medical assessment.…”

Outcomes and Challenges in the Programmatic Implementation of Tuberculosis Preventive Therapy among Household Contacts of Pulmonary TB Patients: A Mixed-Methods Study from a Rural District of Karnataka, India

“…Pre-visit planning, counselling of the index patient and coordination by the medical officers of respective primary health centres helped in complete contact tracing and screening of all the household contacts for TB symptoms. Planning contact visits during weekends or holidays might help in improving the coverage but are less likely to be feasible with the available staff and facilities in the study setting [ 6 , 19 ]. In a study with a high HIV–TB burden, active TB case finding among the HHCs was found to have higher case detection compared to passive case finding [ 20 ].…”

“…However, about 2.2 million (55% of the target) household contacts <5 years and only 2 million household contacts aged ≥5 years (10% of the target) received TPT between 2018 and 2022 [ 1 ]. A recent meta-analysis (2022) reported that the coverage of household contact screening and TPT varied from 14% to 100% in low- and middle-income countries [ 6 ]. Studies from similar settings have reported sub-optimal implementation of contact tracing and TPT due to challenges in the identification of household contacts, poor access to testing for TBI, lack of awareness about TPT among healthcare providers and contacts, inadequate supply of TPT drugs and low prioritisation of TPT in the programme [ 7 , 8 , 9 ].…”