#113 – Varsha Venugopal on using gossip to help vaccinate every child in India

Our failure to get every kid in the world all of their basic vaccinations on time leads to 1.5 million deaths every year.
According to today’s guest, Varsha Venugopal, for the great majority this has nothing to do with weird conspiracy theories or medical worries — in India 80% of undervaccinated children are already getting some shots. They just aren’t getting all of them, for the tragically mundane reason that life can get in the way.
As Varsha says, we’re all sometimes guilty of “valuing our present very differently from the way we value the future,” leading to short-term thinking, whether about going to the gym or getting vaccines.
So who should we call on to help fix this universal problem? The government, extended family, or maybe village elders?
Varsha says that research shows the most influential figures might actually be local gossips.
In 2018, Varsha heard about the ideas around effective altruism for the first time. By the end of 2019, she’d gone through Charity Entrepreneurship’s strategy incubation program, and quit her normal, stable job to co-found Suvita, a nonprofit dedicated to improving the uptake of immunisation in India, which focuses on two models:
- Sending SMS reminders directly to parents and carers
- Gossip
The first one is intuitive. You collect birth registers, digitise the paper records, process the data, and send out personalised SMS messages to hundreds of thousands of families. The effect size varies depending on the context, but these messages usually increase vaccination rates by 8–18%.
The second approach is less intuitive and isn’t yet entirely understood either.
Here’s what happens: Suvita calls up random households and asks, “If there were an event in town, who would be most likely to tell you about it?”
In over 90% of the cases, the households gave both the name and the phone number of a local ‘influencer.’
And when tracked down, more than 95% of the most frequently named ‘influencers’ agreed to become vaccination ambassadors. Those ambassadors then go on to share information about when and where to get vaccinations, in whatever way seems best to them.
When tested by a team of top academics, it raised vaccination rates by 10 percentage points, or about 27%.
The advantage of SMS reminders is that they’re easier to scale up. But Varsha says the ambassador program isn’t actually that far from being a scalable model as well.
A phone call to get a name, another call to ask the influencer to join, and boom — you might have just covered a whole village rather than just a single family.
Suvita got this idea from original Poverty Action Lab (J-PAL) studies, which found that community gossips were much more effective at communicating a simple piece of information than other possible options — including village elders.
In Karnataka, India, villagers were told about a phone-based raffle. Villages with at least one gossip saw an average of 65% more calls to the raffle phone number compared to villages with no gossips.
In a related large-scale randomised trial run in the state of Haryana, J-PAL specifically compared different combinations of interventions to see which mix would have the most impact for a given budget.
They looked at various combinations of three policy tools: mobile credit directly to parents and carers, text reminders directly to parents and carers, and this gossip idea.
They found that adding local ambassadors and text messages to the government’s routine immunisation programme produced the most vaccinations per dollar spent, and was about 10% more cost effective than the government’s existing vaccine promotion efforts.
Varsha says that Suvita has two major challenges on the horizon:
- Maintaining the same degree of oversight of their surveyors as they attempt to scale up the programme, in order to ensure the programme continues to work just as well
- Deciding between focusing on reaching a few more additional districts now vs. making longer-term investments that could build up to a future exponential increase
In this episode, Varsha and Rob talk about making these kinds of high-stakes, high-stress decisions, as well as:
- How Suvita got started, and their experience with Charity Entrepreneurship
- Weaknesses of the J-PAL studies
- The importance of co-founders
- Deciding how broad a programme should be
- Varsha’s day-to-day experience
- And much more
Get this episode by subscribing to our podcast on the world’s most pressing problems and how to solve them: type 80,000 Hours into your podcasting app. Or read the transcript below.
Producer: Keiran Harris
Audio mastering: Ben Cordell
Transcriptions: Katy Moore
















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