key: cord-0933437-8p8riuaf
authors: Rotulo, Gioacchino Andrea; Casalini, Emilio; Brisca, Giacomo; Piccotti, Emanuela; Castagnola, Elio
title: Unexpected peak of bronchiolitis requiring oxygen therapy in February 2020: Could an undetected SARS‐CoV2‐RSV co‐infection be the cause?
date: 2021-03-03
journal: Pediatr Pulmonol
DOI: 10.1002/ppul.25331
sha: 612eb0d1b976f2a3499156deb2b9c21e58d07ace
doc_id: 933437
cord_uid: 8p8riuaf

nan

Unexpected peak of bronchiolitis requiring oxygen therapy in February 2020: Could an undetected SARS-CoV2-RSV co-infection be the cause?

To the Editor, In the current winter season, children's hospitals may have to face the seasonal outbreak of bronchiolitis in a never seen context of coronavirus disease 2019 (COVID-19) pandemic. Respiratory syncytial virus (RSV) is the most common cause of bronchiolitis among infants less than 12 months, presenting with a seasonal pattern with greater prevalence in the winter and spring months. 1 Severe acute respiratory syndrome coronavirus 2 (SARS-CoV2) officially appeared in Italy just as the RSV-bronchiolitis season was winding down. As a result, there was never a real overlap between SARS-CoV2 and RSV.

However, several authors hypothesized that SARS-CoV2 was present in northern Italy some weeks before the first Italian confirmed case on February 20, 2020. [2] [3] [4] [5] As a result, we suspected that this virus, circulating as early as 2020, may have aggravated the course of some infants with bronchiolitis.

We performed a retrospective study to evaluate the frequency and severity of infants presenting with a clinical picture of bronch- No statistically significant differences in age, pre-existing medical conditions (including prematurity), triage severity score at ED presentation, hospitalization rate, and length of stay were noted between groups (Table 1 ). Our results showed no significant differences in the number of patients with viral co-infections between the three seasons either in the entire study period or in the weeks from February 2 to March 9 (Table 1) CoV-2 and other viruses has been described in children. 6 However the description of cases of RSV bronchiolitis with severe respiratory distress who tested positive also for SARS-CoV2 is rare. 7 With this letter we propose the suggestion of a co-circulation of these two viruses that may have led to an increase of severity of bronchiolitis in 2019-2020 compared with the two previous years.

Unfortunately, because of the lack of RT-PCR test in that period this remains an epidemiology-driven hypothesis.

Although COVID-19 appears less severe in children than in adults, the pandemic has taught us that novel, peculiar, and sometimes severe clinical pictures can occur in children. The spike in severe bronchiolitis that we found in February 2020 seems to have no significant epidemiological explanation. We could hypothesize that an undetected SARS- Because several co-infections of SARS-CoV2 with other airborne pathogens are known, 6 we recommend that great caution must be used in the management of childhood respiratory infections to promptly isolate and treat suspected cases and prevent transmission among healthcare workers. Abbreviations: CI, confidence interval; IQR, interquartile range; PCR, polymerase chain reaction; RSV, respiratory sincytial virus.

LETTER TO THE LETTER

Viral bronchiolitis in Children

SARS-CoV-2 has been circulating in northern Italy since December 2019: evidence from environmental monitoring

Evidence of SARS-CoV-2 RNA in an oropharyngeal swab specimen

Could this case be Italy's patient zero?

Unexpected detection of SARS-CoV-2 antibodies in the prepandemic period in Italy. Tumori

A literature review of 2019 novel coronavirus (SARS-CoV2) infection in neonates and children

Can SARS-CoV-2 cause life-threatening bronchiolitis in infants?

We thank all the workers of the Gaslini Institute Emergency Department.