Suvita

India is home to roughly half of the world’s undervaccinated children and loses one child every four minutes to a vaccine-preventable disease. The COVID-19 pandemic has significantly disrupted routine child immunisation programmes, leaving the country even more vulnerable to disease outbreaks. 

We seek to increase the uptake of routine childhood vaccines in India through SMS-based nudges: personalised, curated text messages directly to mothers and caregivers, and text messages and voice recordings to carefully identified community influencers designated as voluntary immunisation ambassadors. This solution is supported by research from Abhijeet Banerjee and others, who found that a combination of local influencers and text reminders to caregivers increased immunisation camp attendance by 25%.

Our highly adaptable and scalable solution can help ensure that more children around the world complete their routine immunisation schedule. We believe this solution also has the potential to boost other evidence-based interventions, such as improve COVID vaccination uptake.

Each year, 19 million children around the world fail to receive their basic vaccinations before their first birthday. Our work is focused on India which has 7 million children not completing their routine vaccination schedule every year. With increased drop-off caused by disruptions related to the COVID-19 pandemic, there is an especially urgent need to get childrens’ immunisation schedule back on track. Our tech model protects infants and communities from future pandemics through information campaigns and behavioural nudges. 

There is significant evidence that the primary barriers to routine vaccination in India are on the demand side. In a nationwide survey, caregivers were four times more likely to identify demand-side barriers than supply-side ones when explaining why their child had missed a vaccine dose. Furthermore, roughly 70% of undervaccinated children in India have received at least one vaccine, indicating that missed appointments are a major barrier to full vaccination. Banerjee and others note in their study in India that while vaccines are free and available, a combination of relative indifference, inertia, and procrastination results in children dropping out. We work in two states Bihar and Maharashtra, both with complete immunisation rates below 75%.

We are closing the demand-side barrier by deploying simple, novel and cost effective SMS based nudges encouraging caregivers to vaccinate their children. 1. We build a network of carefully selected volunteer immunisation ambassadors who share information with new parents in their community about vaccines. Research from Nobel Laureate Abhijit Banerjee and colleagues reported a 10% increase in vaccine uptake after the implementation of the ambassador model. Our pilot in Saran District, Bihar earlier this year successfully demonstrated the operational feasibility of delivering this model entirely remotely. 2. We send caregivers personalised SMS messages reminding them when their child is due for a vaccination. In 2019, our meta-analysis of nine existing randomised controlled trials confirmed that SMS reminders increase vaccine uptake between 3 and 8 percentage points. The latest research by Banerjee et al., 2021 found that combining these two models was the most cost-effective way to increase vaccine uptake, amongst 75 different combinations studied. 

The ambassador model increases awareness and trust in vaccinations. This is an essential first step for lowering the barriers that many caregivers face when considering vaccinating their child. We combine the ambassador model with providing personalised reminders to help caregivers put their knowledge into action. 

Our end users are families who face barriers to infant vaccination, such as not being able to take time off work and not having the right information about when and where to go, which vaccines their child needs and why. Studies suggest that these families are more likely to have low education levels, low income, and be less plugged into the health system in general. We currently work primarily in Bihar and Maharashtra because these states have one of the lowest immunisation rates in India. 

We design our programmes to be accessible to these communities by using the ubiquitously available technology of SMS messages. Whereas almost every family in India has access to a mobile phone, only around ⅔ of people have access to smartphones. SMSs can reach many of our users where smart phone applications such as WhatsApp can not. We are also currently exploring sending recorded voice messages in addition to SMSs, as these are similarly accessible on basic phones, while also overcoming the literacy barrier faced by many. In addition, all our messages are sent in local languages and families do not need to spend any mobile credit to enroll into the programme.

We identify natural influencers in a community network through the magic question: “If there was a fair in town, who is most likely to tell you about it.” The people who are nominated tend to be active and well-connected in their community, meaning that they have a much better idea of key barriers to immunisation within their own networks, so they can take whatever approach they expect will be most effective in their local area. We expect that this also means the ambassador programme is robust to variation in specific needs and barriers if delivered at scale, because in any community it is led by those who know the community best.

In Saran district, Bihar, where we undertook our initial study this year, we conducted Receipt & Understanding surveys with SMS enrollees and interviews with immunisation ambassadors to better understand their motivation and impact. We are also tracking parents’ and caregivers’ responses to ambassadors by giving out a phone number to ambassadors to share with their networks. Our monitoring suggests that more than 98% of text messages are delivered successfully and at least 50% of the users recall the information at a later date. Overwhelmingly ambassadors are enthusiastic and sharing information with their networks, we received about 30 missed calls within one week of sharing a missed call phone number with 45 ambassadors.

The decline in routine vaccination caused by COVID-19 is a major health security threat which WHO’s Director-General warned could cause more suffering and death than COVID itself. We use an existing and ubiquitous technology (SMS messaging) in a novel way, leveraging community networks to promote critical immunisations for infants in undervaccinated, low-income areas. Our SMS-based nudges target common misinformation and mistrust that studies show are responsible for a significant percentage of undervaccination. These demand-side barriers to vaccination include parents’ concerns about vaccination-related illness and side effects, lack of knowledge about vaccines, as well as the timing and location of immunisation clinics. 

The original model for our solution was tested by Abhijit Banerjee and colleagues in a randomised control trial in India. We updated this model and ran a fully remote, SMS and phone call-based study in Saran District, Bihar, India (the J-PAL study relied on in-person contact with community members and ambassadors). We concluded this remote rollout  earlier this year, enrolling more than 50,000 parents in the SMS programme and more than 300 ambassadors in Saran District. The study yielded promising community response rates and feedback, and we are now iterating to improve efficiencies and effectiveness. We plan to undertake a full blown pilot covering all of Saran district (approx. 4 million people) to test different iterations to increase the cost effectiveness of the model from approx. $64 per marginal fully immunised child to $36.