Changes in paediatric respiratory infections at a UK teaching hospital 2016-2021; impact of the SARS-CoV-2 pandemic

Objective To describe the impact of the SARS-CoV-2 pandemic on the incidence of paediatric viral respiratory tract infection in Oxfordshire, UK. Methods Data on paediatric Emergency Department (ED) attendances (0-15 years inclusive), respiratory virus testing, vital signs and mortality at Oxford University Hospitals were summarised using descriptive statistics. Results Between 1-March-2016 and 30-July-2021, 155,056 ED attendances occurred and 7,195 respiratory virus PCRs were performed. Detection of all pathogens was suppressed during the first national lockdown. Rhinovirus and adenovirus rates increased when schools reopened September-December 2020, then fell, before rising in March-May 2021. The usual winter RSV peak did not occur in 2020/21, with an inter-seasonal rise (32/1,000 attendances in 0-3 yr olds) in July 2021. Influenza remained suppressed throughout. A higher paediatric early warning score (PEWS) was seen for attendees with adenovirus during the pandemic compared to pre-pandemic (p = 0.04, Mann-Witney U test), no other differences in PEWS were seen. Conclusions SARS-CoV-2 caused major changes in the incidence of paediatric respiratory viral infection in Oxfordshire, with implications for clinical service demand, testing strategies, timing of palivizumab RSV prophylaxis, and highlighting the need to understand which public health interventions are most effective for preventing respiratory virus infections.

Effect of Aminophylline and Caffeine on Total and Surfactant Phospholipid in Fetal Rabbit Lung

Aminophylline treatment of pregnant rabbits for 2 days, beginning at 25.5 days gestation, produced a significant increase in total phospholipid in fetal lung tissue at 27.5 days gestation, 8.92 +/- 0.76 (mean +/- SEM) mg/g wet lung weight, compared with 5.46 +/- 0.83 in saline-injected control animals (p less than 0.005). Three lines of evidence suggest this was not related to the surfactant system: (1) there was no increase in disaturated phosphatidylcholine in fetal lung tissue, (2) there was no increase in total phospholipid harvested by lung lavage after static lung inflation, and (3) there was no change in the lung deflation pressure-volume curve or stability index. Aminophylline treatment produced no acceleration in general anatomic lung development, as reflected in the ratio of lung air-space capacity to lung tissue weight. Under similar experimental conditions, maternal caffeine treatment had no effect on fetal rabbit lungs.

Distention-produced phospholipid secretion in postmortem in situ lungs of newborn rabbits. Inhibition by specific beta-adrenergic blockade

The secretion of total phospholipid in postmortem in situ lungs of newborn rabbits was examined using the technique of lung lavage after an initial lavage procedure, and then after a period of static air inflation at 30 cm H2O pressure for 45 min. There was a significant reduction in the phospholipid yield with 10(-3) molar DL-propranolol used as the initial lavage fluid, both immediately after the initial lavage procedure (experimental group, 0.29 +/- SE 0.04 mg/g dry lung weight; control group, 0.57 +/- SE 0.09; p less than 0.01) and after static inflation with air (experimental group, 1.14 +/- SE 0.15; control group, 2.22 +/- SE 0.24; p less than 0.001). Preinjection of the breathing newborn rabbit with DL-propranolol was not necessary for this inhibitory effect. There was no significant reduction when 10(-3) molar atropine, lidocaine, D-propranolol, or 10(-5) scopolamine were substituted as the initial lavage fluid, nor was there any reduction when the concentration of DL-propranolol was decreased to 10(-4) or 10(-5) molar. Because D-propranolol has all the properties of DL-propranolol, except 100-fold less beta-adrenergic antagonist activity, the inhibition by propranolol was due to specific beta-adrenergic blockade. In the absence of an intact circulation or a functional central nervous system, it is concluded that surfactant phospholipid secretion is partly controlled by an intrapulmonary neurogenic reflex.