CD40LG and diabetes mellitus: SARS-CoV-2 IgM results were negative in both GICA and ELISA for the 5 Flu A IgM-positive sera, 5 Flu B IgM-positive sera, 5 M. pneumoniae IgM-positive sera, 5 L. pneumophila IgM-positive sera, 6 sera from HIV infection patients, 5 sera from hypertensive patients, and 5 sera from diabetes mellitus patients (Table 1).