In Brazil, 15 percent of deaths have been people under 50 — a rate more than 10 times greater than in Italy or Spain. In Mexico, the trend is even more stark: Nearly one-fourth of the dead have been between 25 and 49. In India, officials reported this month that nearly half of the dead were younger than 60. In Rio de Janeiro state, more than two-thirds of hospitalizations are for people younger than 49.
And here are the speculations:
Because population density is so much higher in much of the developing world — and because so many people must keep working to survive — a far greater share of the population ends up being exposed to the virus.
The virus then spreads through a population that’s less resilient. People in the developing world grapple not only with the diseases that have long been associated with it — malaria, dengue, tuberculosis, HIV/AIDS — but increasingly with those more closely associated with wealthier countries. Rates of diabetes, obesity and hypertension are surging. But treatment for many such illnesses is lacking.