UCLA

Background: Vaccines have been a major medical achievement in modern history, significantly reducing the spread of infectious diseases worldwide. Routine immunization (RI) systems have become a global standard for providing consistent access to vaccination services and protecting communities against vaccine-preventable diseases. The Democratic Republic of Congo (DRC) is the largest country in sub-Saharan Africa with an estimated population between 86 to 106 million and a median age of 17 years. DRC has struggled with low vaccination coverage, with only 35-45% of children being fully immunized for all antigens in the DRC RI schedule. To address this challenge with childhood immunization coverage, the Congolese government, DRC national immunization program worked in conjunction with international partners to develop the Mashako Plan, an emergency strategy to revitalize the routine immunization system. The policy targets key areas such as vaccine availability, equity in vaccination services, monitoring and evaluation, workforce development, and data quality and management. Since its initial rollout of the Mashako Plan in 2018, there have been very few formal evaluations to understand the impact of the policy on the DRC RI system. Methods: By utilizing monthly District Health Information Software 2 (DHIS2) administrative data and Expanded Programme on Immunizations (EPI) mobile supervision data, this study assesses the efficacy of the Mashako plan on the RI system in the DRC. Descriptive analyses of the EPI mobile supervision data identify trends in RI process indicators and an interrupted time series analysis assesses the impact of the Mashako plan on vaccine doses administered for pentavalent (penta) vaccine doses 1 and 3 and measles vaccine. Pentavalent vaccine is a conjugate vaccine that includes Diphtheria, Pertussis, Tetanus, Hepatitis B and Hib and is given at 6, 10 and 14 weeks in the DRC RI system. Furthermore, a comparative interrupted time series analysis determines the effect of the rotavirus vaccine on diarrheal disease cases in children under 5 years of age in Mashako and non-Mashako Plan provinces. Results: The study found that the mean number of immunization sessions held per health facility in each province remained stable over time, irrespective of the COVID-19 pandemic. The availability of vaccines and refrigerators also remained constant during the study period, while health area supervision activities decreased in late 2021, coinciding with internal healthcare worker strikes in DRC. The descriptive analyses of the EPI mobile supervision data showed that the majority of process indicators remained stable or improved over time, including the availability of vaccines and essential supplies. The interrupted time series analysis showed that the implementation of the Mashako Plan was associated with a significant increase in the percentage change of third doses of pentavalent vaccine administered per health facility per month. The baseline percentage change in doses administered at the time of Mashako Plan implementation were 4.3% for penta3, 3.4% for penta1, and 4.9% for measles vaccine. For each additional year of the policy, there was an increase of 3.8% in the percent change of penta3 doses, 3.8% in the percent change of penta1 doses, and 2.2% in the percent change of measles vaccine doses administered above the background rate of increase. The comparative interrupted time series analysis revealed that for the non-Mashako provinces, the implementation of rotavirus vaccine introduction has a negative effect on the incidence of simple diarrhea cases (IRR=0.984), indicating a 1.6% reduction in the incidence of simple diarrhea cases each month may be attributed to the introduction of the rotavirus vaccine. However, in the Mashako group, the IRR for simple diarrhea cases shows a small negative effect (IRR=0.999), indicating a 0.1% reduction in the incidence rate of simple diarrhea each month after rotavirus vaccine introduction may be attributed to the vaccine introduction. However, both groups were very close to null and an ITS analysis with all provinces controlling for Mashako implementation month showed no impact. Conclusion: The results of this study describe the overall initial impact of the Mashako plan in strengthening the RI system in DRC. These analyses demonstrate the influence of cross-cultural and cross-sectoral collaborations on vaccination services. Overall, the studies demonstrate the importance of vaccination programs and interventions in improving public health outcomes in DRC and the need for monitoring and evaluating the impacts of these programs to ensure their success and sustainability. Despite regional differences, the overall positive results provide confidence in the Mashako activities and support the implementation of the next phase of Mashako 2.0. Additional studies should be conducted to assess the regional impacts of the Mashako Plan in DRC.