CD40LG and COVID-19: Regarding sensitivity, recent evidence shows that a humoral immune response is mounted less frequently in patients with mild COVID-19.8 Indeed, the reported sensitivities of the CMIA and ECLIA are 93.9 and 87%, which might have underestimated our seroprevalence.7 Notably, LFIA screening identified 2 patients by positive IgM but negative CMIA and ECLIA at baseline, who eventually had IgG seroconversion in all tests.