JMIR Publications

ABSTRACT

Background:

Latent tuberculosis infection (LTBI) remains a major barrier to tuberculosis (TB) elimination, particularly in community settings where household contacts of patients with active TB are at increased risk of infection and progression to disease. Current tests for LTBI have practical limitations that restrict their use in field and primary care settings. Antigen-based skin testing combined with digital tools for registration, follow-up, and reporting may improve the delivery of household contact screening under routine programme conditions.

Objective:

This study aims to develop and evaluate a CyTB test– and Android application–based screening model for LTBI among household contacts of confirmed TB patients in Rajasthan, India. To assess its feasibility, operational performance, prevalence of LTBI among high-risk groups, and implementation outcomes in a routine programme setting.

Methods:

This protocol describes a community-based interventional implementation study with a mixed-methods design guided by the Logic model and RE-AIM framework, to be conducted over 24 months in the Balesar block, Jodhpur district, Rajasthan. All eligible household contacts of confirmed TB patients identified during the study period will be included, with an estimated screening population of 2400 participants. The intervention combines CyTB-based screening with the TBConnect Android application for participant registration, workflow support, induration recording, follow-up, and reporting. Screening will be implemented through health facility-based, home-based, and camp-based pathways. App-assisted induration measurement will be compared with manual assessment in a subset of participants to evaluate agreement between the two methods. Primary outcomes will include screening coverage, LTBI positivity, concordance between app-assisted and manual readings, and feasibility of the three screening pathways. Secondary outcomes will include health care worker proficiency, application usability, data completeness, operational efficiency, participant acceptability, and adherence to referral and follow-up care.

Results:

Ethical approval for the study has been obtained from the Institutional Ethics Committee of ICMR-National Institute for Implementation Research on Non-Communicable Diseases (ICMR-NIIRNCD), Jodhpur, India. Participant recruitment is expected to begin in 2026, with an estimated sample of approximately 2400 household contacts of confirmed tuberculosis patients. Data collection and follow-up are planned over a 24-month period, and the study results will be disseminated through peer-reviewed publications and presentations at scientific conferences.

Conclusions:

The study is expected to demonstrate that the optimised implementation of CyTB- and TBConnect-based LTBI screening models can substantially improve early detection of latent TB among high-risk populations, thereby providing evidence to guide future programmatic strategies for LTBI screening and TB prevention at the community level.