Lower levels of angiotensin-converting enzyme 2 (ACE2) and transmembrane serine
protease 2 (TMPRSS2) in the nasal epithelium of children may be related to a lower
incidence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection,
compared to adults. However, no direct evidence is available to support this hypothesis. In
this study, we compared the transcript levels of ACE2 and TMPRSS2 in nasopharyngeal
swab samples (n= 234) from children and adult family members within SARS-CoV-2 …

There is accumulating evidence that the lower levels of angiotensin-converting enzyme 2
(ACE2) and transmembrane serine protease 2 (TMPRSS2) in the nasal epithelium of
children may be related to a lower incidence of COVID-19 compared to adults. However, no
direct evidence is available to support this hypothesis. In this study, we compared the
transcript levels of ACE2 and TMPRSS2 in nasopharyngeal swabs (n= 207) from children
and adult members within COVID-19-exposed families and assessed their association with …