*Contacts have symptoms, or asymptomatic contacts have had high-intensity contact with COVID-19. †Optimal timing for convalescent sample needs to be established. ‡Further research needs to determine effectiveness and reliability of repeated sampling. NS – nasopharyngeal swab. OS - oropharyngeal swab. NW - nasopharyngeal wash. BAL - bronchoalveolar lavage. NAAT - nucleic acid amplification test. CBC - complete blood count. CRP - C-reactive protein. ABS - acid-base status. IgG - immunoglobulin G. IgM - immunoglobulin M. Adapted according to reference 28. This evidence concerns the gene CD40LG and COVID-19.