Biochemical and Serological Tests for People Recovering from COVID-19

Aims: The purpose of this study was to detect some biological and serological factors in COVID-19 recovery patients, as well as their relationships with antibody levels 8 months after infection. Materials and Methods: 92 blood samples were obtained; 67 of them had COVID-19 infections 4 months prior, and 25 blood samples served as control samples. The participants' ages ranged from 17-75 year. Determination levels of immunoglobulin IgG and IgM antibodies was carried out on (188) samples of infection over for ages ranging from 15-75 years by using enzyme linked immunosorbant assay  (ELISA). Results: The people under research have 94.03% IgG and 55.22% IgM. Furthermore, the maximum concentration of IgG was seen after 6 months of infection. Aberrant lactate dehydrogenase (LDH) levels were found in 20 people at 41.6% after 4 months, in 25 people at 52.08% after 6 months, and in 8 people at 8.33% after 8 months. In contrast, aberrant C- reactive protein (CRP) levels were found in 10.4% of the participants after 4 to 8 months of infection and 12.5% after 6 months, with no significant association between them. Conclusion: The maximum IgG level was reported 6 months after infection, and the LDH and CRP tests were abnormal 6 months later. On the other hand, 4 months after the infection, both urea and creatinine levels were abnormal, as was the IgG concentration.