The last two percent
I’ve driven the cold chain in northern Nigeria. That means loading vaccines into coolers, strapping the coolers to motorcycles, riding unpaved roads for hours, and hoping the generator at the health post is running when you arrive. If it’s not, you turn around. The vaccines spoil. You try again next week.
We got smallpox because the vaccine was heat-stable, the disease had no animal reservoir, and the Cold War gave both superpowers a reason to cooperate. None of those conditions apply to the diseases we’re fighting now. Polio’s oral vaccine can mutate back to virulence. Malaria has a mosquito reservoir you can’t vaccinate. TB hides in latent infections for decades.
The science is hard. I’m not going to pretend it isn’t. But the science isn’t what stopped us. We’ve had effective polio vaccines since 1955. What stopped us is that the last two percent of any eradication campaign requires reaching people in conflict zones, in communities that don’t trust the vaccinators, in countries where the health infrastructure was gutted by structural adjustment programs in the 1990s.
The pharma incentives camp is right that the money flows wrong. The effective altruists are right that the cost-per-life math is absurd. But neither of them has driven the cold chain. The gap between we have the tools
and the tools reached the child
is not a spreadsheet problem. It’s a road problem, a trust problem, a generator problem.
Where we concede ground: We’ve promised eradication deadlines we couldn’t keep. That eroded the trust we need most.
What would change our mind: A disease eliminated by funding alone, without field infrastructure. It’s never happened.
Read the full synthesis: Why haven’t we eradicated more diseases?