Background: The Vietnam National Expanded Program on Immunization (NEPI) has been successfully implementing a nationwide immunization system since 1985. From the start, the program has increased the immunization coverage rate; however, data on immunization coverage in Vietnam are gathered and aggregated from commune health centers in routine, paper-based reports, which have shortcomings. Also, calculations of coverage are inconsistent at subnational levels, which lead to uncertainty about the size of the target population used as the denominator in coverage calculations. The growth of mobile networks in Vietnam provides an opportunity to apply mHealth to improve the immunization program. In 2012, PATH and the Vietnam NEPI developed and piloted a digital immunization registry, ImmReg, to overcome the challenges of the paper system. A final evaluation was conducted in 2015 to assess the impact of ImmReg, including its use of SMS reminders, on improving the immunization program.
Methods: The study population comprised all children born in Ben Tre province in September and October of 2013, 2014, and 2015, representing pre-intervention, post-intervention, and one year post-intervention, respectively. Data exported from ImmReg were used to compare the immunization rate, dropout rate, and timeliness of vaccination before and after the intervention. Additionally, a rapid survey was conducted to understand the willingness of parents with children due for vaccination to pay for SMS reminder messages on the immunization schedule.
Results: Timely administration of oral polio vaccine, 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 Bacillus Calmette-Guérin (BCG) to measles 1 fell from 12.8% in 2013 to 0% in 2015. Full immunization 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 immunization.
Conclusions: A digital immunization registry that includes SMS reminders can improve immunization coverage and timeliness of vaccination, thereby strengthening the quality and effectiveness of immunization programs. 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, can bring more benefits to the health care system in Vietnam.
Keywords: Mobile health; registries; vaccination.