WASHINGTON, May 28 (WNM/Johns Hopkins Center for Health Security) - As COVID-19 continues to spread beyond China, Europe, and the United States—including to Brazil, Chile, Peru, and Mexico in the Americas—the risk profile appears to be shifting (https://www.washingtonpost.com/world/the_americas/coronavirus-brazil-killing-young-developing-world/2020/05/22/f76d83e8-99e9-11ea-ad79-eef7cd734641_story.html).
While severe cases and deaths in many countries impacted early in the pandemic tended to be reported in older patients, developing countries are increasingly reporting severe cases and deaths among younger individuals. As illustrated by this figure (https://ourworldindata.org/grapher/case-fatality-rate-of-covid-19-vs-median-age), most countries in Africa, South America, and Asia are reporting lower median age for COVID-19 patients, which could be contributing to the elevated incidence of severe disease in younger patients. Notably, 15 percent of COVID-19 deaths in Brazil have been in patients younger than 50 years old, and nearly quarter of deaths in Mexico have been between the ages of 25 and 49 years.
These proportions are orders of magnitude higher than what has been reported in other severely affected countries like Spain and Italy. A myriad of factors—including high population density, pervasive poverty, high prevalence of comorbidities (eg, diabetes, obesity), and poor access to healthcare—could be contributing to a shift toward more severe disease in younger individuals.
As COVID-19 incidence shifts toward developing nations, it will be critical to address all relevant risk factors, including those beyond patient health and demographics, in order to effectively mitigate the COVID-19 risk.