Study design and patients
This was a prospective observational cohort study conducted from 20 July
2020 to 27 August 2020. A total of 101 confirmed COVID-19 cases by
SARS-CoV-2 real-time polymerase chain reaction (PCR) from nasopharyngeal
swabs were enrolled (53 non-hospitalized and 48 hospitalized cases).
Inclusion criteria were: patients aged 13 years or older, both genders,
confirmed mild COVID-19 infection in the non-hospitalized group, and
confirmed moderate infection in patients hospitalized at the Royal
Hospital (RH). Hospitalized patients were recruited within 48 hours of
admission. Patients admitted directly to the ICU at the time of
enrolment were excluded from the study. Mild cases were those who did
not require admission to the hospital due to COVID-19 related illness or
oxygen therapy. In contrast, moderate cases were identified as patients
with hypoxemia </= 94% requiring oxygen support or those with
one or more COVID-19 related organ involvement.
A specified clinical team was assigned to collect data and blood samples
from the inpatients. Outpatients were approached through a daily list of
confirmed COVID-19 patients provided by the Center of Operation
Management for COVID-19 at the Ministry of Health, Oman. Telephonic
calls were conducted to get patients’ consent to participate in the
study after an explanation of the research idea. Patients in the
community were visited by two designated researchers the next day. One
nominated researcher-maintained communication to ensure the adherence of
participants. Patients’ demographics and clinical characteristics were
obtained from non-hospitalized patients directly or for hospitalized
ones through electronic hospital records using a unified data collection
form. Informed consent was obtained from all enrolled patients.