Background: The spread of infectious diseases is a serious problem in prisons. In 2020, the Republic Act 11332 was created which requires prisons to participate in disease surveillance however, there was no such system established in the Philippine Jails. The project aims to establish jail-based surveillance to detect outbreaks and monitor its implementation.

Methods: A developmental qualitative study design was utilized in establishing JBEWS in selected jails in CALABARZON from July to September 2021. Study sites were selected based on jail congestion, proximity to health facilities, and logistical capacity. The researcher conducted records review, key informant interviews, and focus group discussion as the basis for designing and evaluating a jail-based disease surveillance system. We also trained jail personnel on the process of JBEWS.

Results: A total of 20 pilot sites were enrolled in the study. Data sources, data collection mechanism, and existing reporting tools were determined. Disease case definitions were developed and cascaded. A modified tool designed to capture health events was utilized. Twenty-five health personnel were trained. The information gathered was validated, investigated, recorded, and analyzed by the researcher. JBEWS detected a total of ten health events were captured. Top illnesses identified were influenza-like-illness followed by foodborne disease. Nine (90%) health events in jails were reported within 24 hours. All pilot sites responded timely in zero case reporting. Twelve (60%) pilot sites meet the 80% threshold in reporting rate. Lack of manpower, slow internet connection, and multitasking of the workforce were among the challenges encountered.

Conclusions: JBEWS early warning system can be established, implemented and functional in jails. Existing data collection mechanism should be utilized. Perception of jail management and perceived benefits of the system are important information to ensure acceptability and ownership when implemented. Therefore, it is recommended to replicate JBEWS in other jails across the country.