Engagement of Community Health Workers to Improve Immunization Coverage through Addressing Inequities and Enhancing Data Quality and Use Is a Feasible and Effective Approach: An Implementation Study in Uganda

"In neglected, hard-to-reach populations and other areas with low immunization coverage, house-to-house registration, and home visits by the CHWs [community health workers] may be useful in addressing the immunization inequities."

There has been a growing interest in introduction and re-vitalisation of national community health worker (CHW) programmes in low- and middle-income countries (LMICs). In Uganda, CHWs are drawn from and expected to work in their communities. There has been expanding engagement of CHWs to meet population health needs, address health inequities, and improve access to health services. However, there is little evidence of involvement of CHWs in health-facility-based audit meetings that review immunisation data so as to promote tracing and linking of children defaulting on their immunisation schedules. To fill this knowledge gap, the researchers conducted an implementation study to assess the feasibility and use of CHWs in improving use of data, coverage, and equity of immunisation services in Uganda.

The 2-arm cluster randomised study was conducted between July and September 2020 in Mayuge district, located in eastern Uganda. The district has several hard-to-reach areas, including 7 islands that are habitable and a huge forest reserve with people residing there. One sub-county (Bukabooli) with particularly low immunisation coverage was purposively selected for the study. Specifically, 5 health facilities in Bukabooli were stratified into 2 groups (those with measles-rubella (MR) coverage of less than 70% and those with MR coverage above 70%), and 2 facilities were tapped to serve as the control group.

The 3 intervention facilities received a package of interventions including monthly health unit immunisation data audit meetings and defaulter tracking and linkage. The defaulters identified through the audit meetings were then followed up and linked to health facility by CHWs through home visits. Linkage involved advising the caregiver(s) to take their defaulting children to the health facility for catch-up vaccination services. In the subsequent data audit meetings, the CHWs would report on the outcomes of tracing defaulters through home visits. In addition, they would validate the immunisation status of defaulters linked through review of the immunistion registry. As part of the intervention, 5 health workers and 17 CHWs from each intervention-group health facility were given refresher training on: the basics of the Expanded Program on Immunization (EPI); service delivery; data management (including review of EPI performance); vaccine management; and advocacy, communication, and mobilisation. The CHWs were supervised by the health workers involved in EPI service delivery at their respective health facilities to which they were attached.

Immunisation coverage of infants in both arms was determined by a review of records 3 months before and after the study interventions. In addition, key informant and in-depth interviews were conducted among facility-based health workers and CHWs, respectively, at the endline to explore the feasibility of the interventions.

A total of 2,048 children under one year eligible for immunisation were registered in Bukabooli sub-county by CHWs as compared to the estimated district population of 1,889 children, representing a moderate variance of 8.4%. The study further showed that it is feasible to use CHWs to track and link defaulters to points of immunisation services, as more than two-thirds (68%) of the children defaulting returned for catch-up immunisation services. Difference-in-difference analysis demonstrated that the intervention caused a significant 35.1% increase in coverage of Bacillus Calmette-Guérin (BCG) vaccine (confidence interval (CI) 9.00-61.19; p<0.05). The intervention facilities had a 17.9% increase in diphtheria tetanus toxoid and pertussis (DTP3) coverage compared to the control facilities (CI: 1.69-34.1), while for MR, oral polio vaccine third dose (OPV3), and rotavirus vaccine second dose (Rota2) antigens, there was no significant effect of the intervention.

Overall, the CHWs reported that the house-to-house registration was a practical and doable exercise that was also accepted by the community. The CHWs affirmed that it was a reliable way to know the accurate population for immunisation. They further attested that it was a good experience of knowing the true location of eligible children for further follow up. CHWs also reported that, during the audit meetings, they learned how to approach the community to do home visits and how to conduct health education on immunisation during the home visits. CHWs reported that during the study intervention they got more involved with immunisation activities and appreciated their role as a bridge between the community and the health facility. The CHWs reported that home visits advanced equity. as they were able to reach the hard-to-reach households including vulnerable population. All the in-charges of health facilities who were involved in the study appreciated the engagement of CHWs to collect immunisation data at household level and acknowledged that this was a feasible intervention.

The challenges cited by the CHWs were that some parents thought the registration of children was for political ambitions and/or financial gains. Indeed, some households were expecting financial reimbursement for the registration. Other households thought their children were going to be recruited into religious cult groups. Five known vaccine-resistant households refused registration of their children. In addition to hesitancy, the CHWs reported several other reasons for children missing/defaulting on their immunisation schedules, including: religious beliefs prohibiting uptake of vaccination services; restricted movements due to the COVID-19 pandemic; migration of families for economic activities such as farming; fear of multiple injections; domestic violence making women unable to take children for immunisation; and ignorance of the caregivers on the benefits of immunisations.

The CHWs recommended that the house-to-house registration needed to be conducted on a regular basis, at least twice a year. They emphasised the need to plan and facilitate CHWs with logistics to be able to carry out the exercise. They suggested that the community needed to be sensitised on the importance of the house-to-house registration.

Based on the results of the study, the researchers write, "CHWs can play an important role in attaining universal health coverage by strengthening health systems to provide people centered care that is equitable and culturally appropriate....In our study, CHWs were trained, given specific tasks, and regularly supervised. We believe this contributed to their good performance."

In conclusion: "Facilitating monthly health unit immunization data audit meetings for identifying, tracking, and linking defaulters to immunization services are effective means of increasing immunization coverage and equity and should therefore be considered for integration into immunization programs."