This was a cross-sectional study conducted in a dedicated pediatric COVID-19 center in Pune, Maharashtra between 1 April, 2020 and 20 May, 2020. Prior approval was taken from the institutional ethics committee. All children between one month and 18 years of age who tested positive by the RT- PCR technique for nasopharyngeal swab were included in the study – these also included asymptomatic children as per the management guidelines in force. Written informed consent was taken from the parents of all children and assent was taken from children who were greater than 9 years of age. Detailed information including demographic data, travel and contact history, living conditions and overcrowding, symptoms, and presence of co-morbid conditions were taken. The children were examined and categorized as per degree of severity based on standard criteria [2].

Baseline laboratory parameters (complete hemogram and C-reactive protein) were evaluated and repeated as required. Chest radiograph was done in all symptomatic children. On chest X-ray each lung was divided into three zones. Each zone was given a score of 1 if there was any opacity and 0 if there were none. Total score of 3 was considered as 50% involvement [3]. All children admitted were managed as per the hospital protocol. The children were monitored daily for changes in disease severity. Discharge from hospital was as per prescribed World Health Organization (WHO) guidelines which stated that asymptomatic children who tested negative for two nasopharyngeal swabs taken 24 hours apart after day 14 of illness were fit for discharge [4]. 　Overcrowding was defined based on persons per room criteria [5].

Statistical analyses: The data were analyzed using the Statistical Package for Social Sciences (SPSS) software version 25.0. Spearman’s Rho correlation coefficient was used to determine the correlation with disease severity. A P value <0.05 was considered significant.

A total of 178 children presented to us with suggestive features during the study duration, of which, 153 were negative and 25 were positive for SARS-CoV-2 by RT-PCR. Another 25 children with a positive RT-PCR were referred from other hospitals. Thus, a total of 50 children (56% males) with median (IQR) age of 6 (2-12) years were included. Majority (82%) of the cases hailed from containment zones in Pune. There was history of positive household contact in 45 (90%) children; with 42 having family members with mild illness and three with severe illness. Travel history to affected area was documented in only one child (Table I).

Table I Epidemiological and Clinical Characteristics of Children With SARS-CoV-2 
Infection in Pune, 2020 (N=50)

More than half (58%) of the children were asymptomatic while 20 (40%) had mild symptoms. In symptomatic children, fever was the chief complaint in 17 (34%). None of the children had hypoxemia measured by pulse oximetry. Only two children had co-morbidities; one child had history of simple febrile seizures, and another had underlying type I diabetes mellitus and had presented with diabetic ketoacidosis. Immunization was complete in 32 (64%) of the children as per universal immunization program, and 49 (98%) children had a BCG scar.

Chest radiograph was done in 20 (95.2%) of 21 symptomatic children. It was found to be normal in 18 (85.7%), while two showed bilateral lower zone haziness (<50%). The disease category for all patients remained same all through the hospital stay and no mortality was seen.

Table II  Laboratory Investigations of Children With SARS-CoV-2 Infection in Pune, 2020 (N=50)

Majority of children in our study were detected in the identified containment zones, most of them reporting exposure to a positive household contact. Majority of the children were either asymptomatic or had mild disease.

Most children were from lower socio-economic groups, a pattern also witnessed in other countries [6]. Though the disease was seen in all age groups, children less than five years of age accounted for nearly half the cases. This can be attributed to the inability of this age group to comprehend and follow social distancing norms and their frequent close contact with parents.

Pediatric observational studies published early in the spread across China reported similar clinical findings with fever being the most common symptom followed by cough and sore throat [7]. A recent meta-analysis has also shown that most of the patients have mild to moderate disease (96%) with only 1% of all the symptomatic pediatric cases being critically sick [8]. The reported mortality rate of COVID-19 in children is less than 1% [9]. Various hypotheses have been proposed for the lesser disease severity in children [10], though a definite answer is still awaited.

Malnutrition has been deemed a risk factor in adult COVID-19 [11]. In children, malnutrition is known to foster infections; however, in this study, majority of the children were well-nourished as per weight-for-age criteria. The hematological profile of adults with COVID-19 has demonstrated leucopenia with associated neutrophilia, lymphopenia; eosinopenia and thrombocytopenia. Also, higher NLR, LMR and PLR have been associated with severe disease and used for prognostication [12]. Leucopenia, however, was seen in only 6% of our children and there was no evidence of lymphopenia, thrombo-cytopenia or eosinopenia. Increasing NLR in our study showed a moderate positive correlation coefficient while LMR showed a negative correlation. High CRP values have now become synonymous with severe COVID-19 infection among adults as seen in majority of the studies [13]. The value of CRP did not correlate with disease severity in our study. These discordant results may be due to the majority of our patients being asymptomatic or mildly symptomatic, or due to a different history of antigen exposure and immune response.

The findings of our study are limited by the size of the cohort and may require further validation by a study with a larger sample size. Being a study in the initial phase of the pandemic with lockdown in place, it may not cover the entire spectrum of clinical presentations, severity and magnitude of SARS-CoV-2 in children from different geographical areas. We could also not collect data for calculation of body mass index (BMI) and Z-scores.

In conclusion, our study shows that there is a higher disease burden in lower-socioeconomic groups with majority of children having a positive household contact. A milder disease pattern is seen in majority of children with COVID-19.

Ethical approval: Institutional Ethics Committee of Bharati Vidyapeeth Medical College and Hospital; No. BVUDMC/IEC/1B, dated 10 April, 2020.

Contributors: VSR,BS,AP,MC: management of the patients; VSR,BS: collected the data, reviewed the literature and drafted the first version of the manuscript; BS,JSO,NM,SL: conceptualized the study, reviewed the literature, revised the manuscript and critically reviewed the manuscript. All authors contributed to manuscript preparation and approved the final version of the manuscript.

Funding: None; Competing interests: None stated.