ACE2 and infection: A study done comparing infection and mortality risk in COPD and asthma patients [26] found that patients diagnosed with COPD had a greater risk of developing severe sickness (aOR: 23.433; 95% CI 1.525–360.135; P < 0.01) in comparison to COVID-19 patients diagnosed with asthma, but this could also be linked to the increased ACE2 expression found in COPD patients versus asthma patients.