Although the major pathogen responsible for bronchiolitis remains RSV, the infection can also be caused by RV and hBoV. Demographic characteristics and clinical severity of the disease may depend on the number of viruses or on the specific virus detected.

@ERSpublications Epidemiological evidence shows that SARS-CoV-2 infection in children is less frequent and severe than adults. Age-related ACE2 receptor expression, lymphocyte count and trained immunity might be the keystone to reveal children's secret. https://bit.ly/2QWpWxK Cite this article as: Cristiani L, Mancino E, Matera L, et al. Will children reveal their secret? The coronavirus dilemma. Eur Respir J 2020; 55: 2000749 [https://doi.

Background: Gastrointestinal disorders are frequent in COVID-19 and SARS-CoV-2 has been hypothesized to impact on host microbial flora and gut inflammation, infecting intestinal epithelial cells. Since there are currently no coded therapies or guidelines for treatment of COVID-19, this study aimed to evaluate the possible role of a specific oral bacteriotherapy as complementary therapeutic strategy to avoid the progression of COVID-19. Methods: We provide a report of 70 patients positive for COVID-19, hospitalized between March 9th and April 4th, 2020. All the patients had fever, required non-invasive oxygen therapy and presented a CT lung involvement on imaging more than 50%. Forty-two patients received hydroxychloroquine, antibiotics, and tocilizumab, alone or in combination. A second group of 28 subjects received the same therapy added with oral bacteriotherapy, using a multistrain formulation. Results: The two cohorts of patients were comparable for age, sex, laboratory values, concomitant pathologies, and the modality of oxygen support. Within 72 h, nearly all patients treated with bacteriotherapy showed remission of diarrhea and other symptoms as compared to less than half of the not supplemented group. The estimated risk of developing respiratory failure was eight-fold lower in patients receiving oral bacteriotherapy. Both the prevalence of patients transferred to ICU and mortality were higher among the patients not treated with oral bacteriotherapy. d'Ettorre et al. Bacteriotherapy in Treating COVID-19 Conclusions: A specific bacterial formulation showed a significant ameliorating impact on the clinical conditions of patients positive for SARS-CoV-2 infection. These results also stress the importance of the gut-lung axis in controlling the COVID-19 disease.

Detection of a broad number of respiratory viruses is not undertaken currently for the diagnosis of acute respiratory infection due to the large and always increasing list of pathogens involved. A 1-year study was undertaken on children hospitalized consecutively for acute respiratory infection in a Pediatric Department in Rome to characterize the viruses involved. Two hundred twenty-seven children were enrolled in the study with a diagnosis of asthma, bronchiolitis, bronchopneumonia, or laringo-tracheo bronchitis. A molecular approach was adopted using specific reverse transcription (RT)-PCR assays detecting 13 respiratory viruses including metapneumovirus (hMPV) and the novel coronaviruses NL63 and HKU1; most amplified fragments were sequenced to confirm positive results and differentiate the strain. Viral pathogens were detected in 97 samples (42.7%), with 4.8% of dual infections identified; respiratory syncytial virus (RSV) was detected in 17.2% of children, followed by rhinovirus (9.7%), parainfluenza virus type 3 (PIV3) (7.5%), and influenza type A (4.4%). Interestingly, more than half the patients (9/17) that have rhinovirus as the sole respiratory pathogen had pneumonia. HMPV infected children below 3 years in two peaks in March and June causing bronchiolitis and pneumonia. One case of NL63 infection is described, documenting NL63 circulation in central Italy. In conclusion, the use of a comprehensive number of PCR-based tests is recommended to define the burden of viral pathogens in patients with respiratory tract infection.

The association between bronchiolitis and recurrent wheezing remains controversial.In this prospective study, we assessed risk factors for recurrent wheezing during a 12-month follow-up in 313 infants aged ,12 months hospitalised for their first episode of bronchiolitis. Demographic, clinical and laboratory data were obtained with a questionnaire and from medical files. A total of 14 respiratory viruses were concurrently assayed in nasal washings. Parents were interviewed 12 months after hospitalisation to check whether their infants experienced recurrent wheezing.The rate of recurrent wheezing was higher in infants with bronchiolitis than in controls (52.7 versus 10.3%; p,0.001). Multivariate analysis identified rhinovirus (RV) infection (OR 3.3, 95% CI 1.0-11.1) followed by a positive family history for asthma (OR 2.5, 95% CI 1.2-4.9) as major independent risk factors for recurrent wheezing.In conclusion, the virus most likely to be associated with recurrent wheezing at 12 months after initial bronchiolitis is RV, a viral agent that could predict infants prone to the development of recurrent wheezing.