Age-Related Vulnerability to Coronavirus Disease 2019 (COVID-19): Biological, Contextual, and Policy-Related Factors.

The detailed facts surrounding the coronavirus disease 2019 (COVID-19) pandemic are still evolving; however, one of the most shocking aspects of the COVID-19 pandemic is how lethal this condition is for the older population (Dowd et al., 2020). The risk for death and severe illness with COVID-19 is best predicted by age. The likelihood of death increases exponentially with age among those who contract the virus in all countries where this has been examined (Figure 1). Figure 1 shows the percent of confirmed cases ending in mortality, by age, for five countries near the beginning of June. In every country, the percent dying increases sharply after age 50, and the highest rates occur among the oldest persons. The age pattern is clear across the countries even though the mortality levels are quite different; the United States has had a much greater number of cases and deaths than the other countries in this figure, but the mortality level was higher in Italy. This difference in levels could be influenced by the proportion of diagnosed cases, which depends on testing, treatment of cases, and whether COVID-19 deaths include only those confirmed with a diagnostic test or include both confirmed and probable deaths (Sung & Kaplan, 2020). Even with these differences, the pattern of an exponential increase in death with age is clear.