Digital Immunization Registry: Evidence for the Impact of mHealth on Enhancing the Immunization System and Improving Immunization Coverage for Children under One Year Old in Vietnam

In 2012, PATH and the Vietnam Vietnam National Expanded Program on Immunization (NEPI) developed and piloted a digital immunisation registry, ImmReg, to overcome the shortcomings of the existing paper-based immunisation data collection system. This article shares the results of a final evaluation conducted in 2015 to assess the impact of ImmReg, including its use of short message service (SMS, or text) reminders to engage caregivers, on improving the immunisation programme.

PATH and NEPI decided that, for better monitoring of the timeliness of EPI vaccination, a registration and reporting system was needed that could efficiently manage the due dates for vaccination of children and report the most accurate figure of full immunisation coverage. The custom software programme, developed locally, takes advantage of the power of automatic aggregation and calculation functions to ease some of the reporting burden on health workers, while using SMS messages to possibly help increase on-time immunisation in the community. In January 2012, PATH launched ImmReg in all 17 communes in Mo Cay Nam district in Ben Tre province, located in the Mekong Delta area of Vietnam. In 2014, PATH received funding to expand ImmReg to all 164 communes in the nine districts in Ben Tre province.

The assessment was carried out in Ben Tre, where all children born were registered into ImmReg. The data used in this study, exported from ImmReg, included all children born in Ben Tre province in September and October of 2013, 2014, and 2015. These cohorts represent pre-intervention, post-intervention, and one year post-intervention, respectively. A comparison of full immunisation rate, dropout rate, and timeliness of vaccination before and after intervention was done. In addition, a rapid survey was conducted to understand the willingness to pay for an immunisation reminder SMS. The survey sample included parents who had children due for vaccination in the selected communes.

Full immunisation, as defined by NEPI, is when a child has received his or her 8 childhood vaccines: Bacillus Calmette-Guérin (BCG), Quinvaxem (pentavalent diphtheria-pertussis-tetanus, hepatitis B, and Haemophilus influenzae type b) doses 1 through 3, oral polio vaccine (OPV) doses 1 through 3, and the first dose of measles vaccine. The timeliness of receipt of a specific vaccine is determined by the recommended age for receipt of the vaccine.

Timely administration of OPV, Quinvaxem, and measles 1 vaccine significantly increased over time from baseline to post-intervention to one year post-intervention. In particular, the timeliness of vaccination with the third dose of Quinvaxem increased from 53.6% to 65.8% to 77.2%. For measles 1 vaccine, the rate increased from 70.4% to 76.2% to 92.3%. In addition, the dropout rate from Quinvaxem 1 to Quinvaxem 3 declined from 4.2% in 2013 to 0% in 2015, and the dropout rate from BCG to measles 1 fell from 12.8% in 2013 to 0% in 2015. Full immunisation coverage of children under one year old increased significantly from 75.4% in 2013 to 81.7% in 2014 to 99.2% in 2015. Also, survey results indicated that 93.3% of interviewees were willing to pay for SMS reminders for immunisation.

The researchers indicate that the results suggest that "the integration of a mHealth component into a digital health system can enhance the impact of the system. Health workers with access to ImmReg at all levels clearly understand the benefits of the system. For this reason, the system has been sustained and used after the project ended. With mobile application of ImmReg, health workers can easily access the system to track or enter immunization data anytime and anywhere using their mobile phones or tablets. ImmReg is helpful not only for health workers but also for parents, who recognize the benefit of SMS reminders in helping them bring their children to immunization events on time."

That said, they caution that "the dominant form of mHealth programs in developing countries is characterized by small-scale pilots or informal projects with limited implementation....Therefore, careful evaluation of the challenges and lessons learned from Ben Tre's pilot will be very valuable for scale-up decisions and strategies. An important point to keep in mind is that mHealth is merely a means to an end; thus, as much as we appreciate the enormous opportunities offered by new technologies, health programs should focus on the actual impact these tools have on individual health workers, patients, and the health of the general public. The human factor is especially pivotal in the implementation strategy."

In conclusion, this study found that "a digital immunization registry and SMS immunization reminders can improve immunization coverage and the timeliness of vaccination....Integrating this system into the national health information system and leveraging it for other health programs, such as maternal and child health and nutrition as well as infectious disease control, may bring more benefits to the health care system in Vietnam."