Question: Reading about all millions of the vaccine donations the US is planning to make and curious– where should the donations go? Which countries are in greatest need?
Answer: This is such a challenging question since the global need is enormous– the world needs billions of doses. To keep today’s Q&A manageable, I’m going to talk about one approach suggested in a commentary published by Lancet two days ago, Epidemiology, not geopolitics, should guide COVID-19 vaccine donations. The authors argue that in order to be most impactful, donated vaccinations should go to countries that have the greatest need in the short- and intermediate-term, as defined by expected COVID deaths per population. The authors use a Susceptible–Exposed–Infectious–Recovered (SEIR) model to estimate COVID mortality on a country-by-country basis for the period of June 1st through August 31st, 2021 (Figure 1). They suggest, “On the basis of the estimates in the figure, the areas of greatest need, taking into account the available data on secured vaccines and likely SARS-CoV-2 variants, are in Latin America, central and eastern Europe, central Asia, and South Africa—settings that have received among the fewest COVID-19 vaccine donations to date.” If one were to agree with the author’s approach, donations would go to those countries who are most likely to have the highest COVID mortality over the summer unless swift action is taken. Of course, this approach has its limitations; models are only as good as the data they use (inputs) and assumptions they make (further discussed in previous posts describing modeling, including Q&A of 4/5/20, Q&A of 5/4/20).
“If measuring the present is hard, predicting the future is even harder. The mathematical models that have guided the world’s pandemic responses have been often portrayed as crystal balls. That is not their purpose. They instead describe a range of possibilities, and help scientists and policy makers to simulate what might happen pending different courses of action. Models reveal many possible fates, and allow us to choose one. And while distant projections are necessarily blurry, the path ahead is not unknowable.”
–Ed Yong for The Atlantic
Figure 1. Estimated COVID mortality rate by country, June-August 2021 (from Lancet)
