ACE2 and COVID-19: This study found that there is an effect of coronavirus infection on the bone strength measured by the Mean of the OPG level, which was found to be highly significant in the serum of post-COVID-19 patients when compared with non-COVID-19 subjects (P-value = 0.001), but the Mean of ACE-2 level was statistically non-significant between the two groups (P-value = 0.13).