CD79A and COVID-19: Report of close contact with COVID-19 cases was also associated with the presence of IgA antibodies: 18 (4.2%) vs. 25 (2.2%), respectively (p = 0.028); IgG detection was also associated with exposure to a confirmed COVID-19 case: 15 (3.4%) vs. 13 (1.1%), respectively (p = 0.002).