Association Between Risk of COVID-19 Infection in Nonimmune Individuals and COVID-19 Immunity in Their Family Members.

Baseline characteristics for nonimmune individuals (n = 1 549 989; 790 276 men [51.0%] and 759 713 women [49.0%]) are presented in Table 1 , for whom a clear trend can be seen toward lower mean (SD) age (51.6 [17.7] years vs 27.3 [15.5] years for 4 immune family members; P < .001), fewer medical diagnoses (myocardial infarction: 30 554 [2.0%] vs 3 [0.4%]; P < .001), lower mean (SD) income (€29 247/US $34 671 [€80 770/US $95 750] vs €9205/US $10 912 [€14 242/US $16 883]; P < .001), and a lower proportion of individuals who were born in Sweden (1 267 527 [81.8%] vs 534 [72.7%]; P < .001) as the number of immune family members increased.

also in 19,460 other papers