ACE2 and COVID-19: Initial concerns were also raised regarding the medical treatment of hypertension with adverse COVID-19 outcomes, as studies in animals have shown that the use of renin–angiotensin system blockers–angiotensin-converting enzyme inhibitors and angiotensin receptor blockers result in the upregulation of angiotensin-converting enzyme 2 (ACE2) expression, which is an entry factor for SARS-CoV-2 [13].