Listened to an illuminating episode of the Global Dispatches podcast recently. The featured guest was Dr. Angela Chang, who discussed a groundbreaking study on the links between vaccines and poverty prevention.

This is the first study that looks closely at the non-health impact of vaccines. It’s impressive: the research uses statistical modeling and analysis to highlight important connections between development and medicine. More importantly, it yields results that can directly inform public health policies.

To measure the non-health impact of vaccines, Dr. Chang’s team looked at two main figures:

  • averted deaths
  • averted cases of medical impoverishment (brought on by lost income, treatment expenses, etc.)

One key takeaway is that vaccinations have a markedly larger impact on death and medical impoverishment figures from poorer sectors. This makes sense: poorer households are more vulnerable to disease and the financial risks of treatment. As the paper itself states:

Although the poorest quintiles experienced the lowest vaccine coverage rates, they enjoyed the most health benefits in terms of absolute number of averted deaths: The poorest quintile accounted for the largest share of deaths averted by all vaccines (23–34 percent), and the poorest two quintiles accounted for over half of the deaths averted by most vaccines.

[…]

The number of medical impoverishment cases decreased greatly with increasing wealth (exhibit 2). As expected, the vast majority of averted impoverishment cases occurred in the poorest quintiles, and fewer than 20,000 cases were averted in the richest quintile. For many vaccines … more than 40 percent of the averted cases occurred in the poorest quintile. Overall, the results suggest that vaccination would lead to an important reduction in medical impoverishment cases in the poorer quintiles.

Chang, Angela et. al. “The Equity Impact Vaccines May Have On Averting Deaths And Medical Impoverishment In Developing Countries.” Health Affairs, vol. 37, no. 2, 2018. https://doi.org/10.1377/hlthaff.2017.0861.

Distributional impact is another important point, as Mark Leon Goldberg highlighted in the interview as well. The impact of vaccines varies — some bring greater benefits to the poor than others. As the paper points out, viewing vaccination programs through this lens can help policymakers prioritize initiatives with a bigger projected impact on the poor.

In other words, the paper is a big step towards learning how we can better wield health policies to achieve social equity.

The study has major limitations, mostly because global data is scarce. For example, estimates of incurred costs for specific diseases are spotty at best, and certainly difficult to find the more countries you want to examine. Still, it’s a great first step, and I’m glad to have heard about it from the podcast.

You can listen to the episode here. The full paper is available online (thank you, open access). It’s not too technical a read, and it should take no more than 30 minutes to go through. Please read it when you can.