Materials and Methods
Clinical definition and classification
Children are defined as being less than 18 years old. Referring to the
guidelines on the diagnosis and treatment of SARS-CoV-2 infected
pneumonia (the sixth edition draft) issued by the National Health
Commission of China.6 Fever is recognized when body
temperature is higher than or equal to 37.3℃.Respiratory symptoms
include nasal congestion, runny nose, sneezing,sore throat, cough,
expectoration, chest pain,
dyspnea,etc.Digestive symptoms
include nausea, vomiting, abdominal pain, diarrhea, etc.A real-time
reverse transcriptase polymerase chain reaction (RT-PCR) was used to
detect SARS-CoV-2 RNA positive in
nasopharyngeal swab or anal swab samples to confirm diagnosis.All chest
CT images were reviewed by two experienced pediatric radiologists. If
unilateral or bilateral lung fields have any of the features as
follows:(a) ground glass opacities;(b) consolidations with surrounding
halo sign;(c) nodules;(d) residual fiber strips;(e) lymphadenopathy.The
result is defined as positive CT findings of viral
pneumonia.7-8 Family cluster infection is defined as
the occurrence of any of the following criteria in 2 or more family
members within a period of less than 1 week: (a) fever;(b) respiratory
and or digestive symptoms;(c) positive CT findings of viral pneumonia.
Discharge criteria: All clinical symptoms of the COVID-19 children
disappeared, absorption of lung lesions improved, and two consecutive
nucleic acid tests of both nasopharyngeal swab and anal swab were
negative at least 24 hours apart.
Follow-up procedure after discharge: All discharged COVID-19 children
were isolated and observed at home for 2 weeks, and community health
workers visited house twice a week to collect nasopharyngeal swabs for
SARS-CoV-2 RNA detection.They were also followed-up once every two weeks
for at least two additional weeks after isolation. Among them, the RP
pediatric patients were
re-admitted to hospital for further medical observation and close
contacts were also followed-up.The rest of the recovered non-RP
pediatric patients were closely followed-up outside the hospital.
Data collection
We conducted a retrospective study.The medical records of all COVID-19
children were reviewed.Clinical and laboratory data of the first two
days after admission were collected.Based on the SARS-CoV-2 RNA test
results during follow-up, the RP group was defined as at least one
positive test result. The control group was defined as all tests were
negative and no suspicious clinical symptoms appeared, and the
differences between the two groups were compared.
Inclusion criteria: all confirmed pediatric cases.
Exclusion criteria: lost follow-up
cases.
Statistical Analysis
All analyses were conducted by using of IBM Statistical Product and
Service Solutions software Version 24 (SPSS Inc,Chicago,IL).Continuous
variables were summarized as the median with interquartile ranges (IQRs)
or mean with standard deviations (SDs),
median [IQR] or [mean±SD],
depending on whether their distributions were normal or not.Comparisons
of categorical variables were performed using the Pearson Chi‑square
test. Odds ratios (ORs) and 95% confidence intervals (CIs) were
calculated for statistically significant variables.The parametric tests
(independent sample Student t-test) or non-parametric tests
(Mann-Whitney U test) were used to analyse variables.P <.05
was considered as statistically significant in all tests if applied.