Social distancing measures for COVID-19 are changing winter season

The impact of non-pharmaceutical interventions on community non-SARS-CoV-2 respiratory infections in preschool children

BACKGROUND

Effects of non-pharmaceutical interventions during the pandemic were mainly studied for severe outcomes. Among children, most of the burden of respiratory infections is related to infections which are not medically attended. The perspective on infections in the community setting is necessary to understand the effects of the pandemic on non-pharmaceutical interventions.

METHODS

In the unique prospective LoewenKIDS cohort study, we compared the true monthly incidence of self-reported acute respiratory infections (ARI) in about 350 participants (aged 3-4 years old) between October 2019 to March 2020 (pre-pandemic period) and October 2020 to March 2021 (pandemic period). Parents reported children's symptoms using a diary. Parents were asked to take a nasal swab of their child during all respiratory symptoms. We analysed 718 swabs using Multiplex PCR for 25 common respiratory viruses and bacteria.

RESULTS

During the pre-pandemic period, on average 44.6% (95% CI: 39.5-49.8%) of children acquired at least one ARI per month compared to 19.9% (95% CI: 11.1-28.7%) during the pandemic period (Incidence Rate Ratio = 0.47; 95% CI: 0.41-0.54). The detection of influenza virus decreased absolute by 96%, respiratory syncytial virus by 65%, metapneumovirus by 95%, parainfluenza virus by 100%, human enterovirus by 96% and human bocavirus by 70% when comparing the pre-pandemic to the pandemic period. However, rhinoviruses were nearly unaffected by NPI. Co-detection (detection of more than one virus in a single symptomatic swab) was common in the pre-pandemic period (222 of 390 samples with viral detection; 56.9%) and substantially less common during the pandemic period (46 of 216 samples; 21.3%).

CONCLUSION

Non-pharmaceutical interventions strongly reduced the incidence of all respiratory infections in preschool children but did not affect rhinovirus.

An overview on viral interference during SARS-CoV-2 pandemic

Respiratory viruses represent the most frequent cause of mortality, morbidity and high healthcare costs for emergency visits and hospitalization in the pediatric age. Respiratory viruses can circulate simultaneously and can potentially infect the same host, determining different types of interactions, the so-called viral interference. The role of viral interference has assumed great importance since December 2019, when the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) came on the scene. The aim of this narrative review is to present our perspective regarding research in respiratory virus interference and discuss recent advances on the topic because, following SARS-CoV-2 restrictions mitigation, we are experimenting the co-circulation of respiratory viruses along with SARS-CoV-2. This scenario is raising many concerns about possible virus-virus interactions, both positive and negative, and the clinical, diagnostic and therapeutic management of these coinfections. Moreover, we cannot rule out that also climatic conditions and social behaviours are involved. Thus, this situation can lead to different population epidemic dynamics, including changes in the age of the targeted population, disease course and severity, highlighting the need for prospective epidemiologic studies and mathematical modelling able to predict the timing and magnitude of epidemics caused by SARS-CoV-2/seasonal respiratory virus interactions in order to adjust better public health interventions.

Urgent Hospitalizations Related to Viral Respiratory Disease in Children during Autumn and Winter Seasons 2022/2023

AIM

The loosening of social distancing measures over the past two years has led to a resurgence of seasonal epidemics associated with respiratory viral infections in children. We aim to describe the impact of such infections through urgent hospitalizations in a pediatric emergency department.

METHODS

We performed a retrospective review of medical records of all children and adolescents with a positive nasal swab admitted at the children's hospital IRCCS Burlo Garofolo of Trieste, in Italy, from September 2021 to March 2022, and September 2022 to March 2023.

RESULTS

Respiratory Syncytial Virus and Influenza viruses accounted for up to 55% of hospitalizations for respiratory infections during the study periods. During the last season, the number of hospitalizations related to the Influenza virus was five times higher than those related to SARS-CoV-2 (25% vs. 5%). Respiratory Syncytial Virus was associated with a greater need for respiratory support, mostly HFNC (High Flow Nasal Cannula).

CONCLUSIONS

Respiratory Syncytial Virus and Influenza virus had a more significant impact on urgent hospitalizations during the past wintery seasons than SARS-CoV-2.

SARS-CoV-2-related bronchiolitis: a multicentre international study

BACKGROUND

Bronchiolitis is the main acute lower respiratory tract infection in infants. Data regarding SARS-CoV-2-related bronchiolitis are limited.

OBJECTIVE

To describe the main clinical characteristics of infants with SARS-CoV-2-related bronchiolitis in comparison with infants with bronchiolitis associated with other viruses.

SETTING, PATIENTS, INTERVENTIONS

A multicentre retrospective study was conducted in 22 paediatric emergency departments (PED) in Europe and Israel. Infants diagnosed with bronchiolitis, who had a test for SARS-CoV-2 and were kept in clinical observation in the PED or admitted to hospital from 1 May 2021 to 28 February 2022 were considered eligible for participation. Demographic and clinical data, diagnostic tests, treatments and outcomes were collected.

MAIN OUTCOME MEASURES

The main outcome was the need for respiratory support in infants testing positive for SARS-CoV-2 compared with infants testing negative.

RESULTS

2004 infants with bronchiolitis were enrolled. Of these, 95 (4.7%) tested positive for SARS-CoV-2. Median age, gender, weight, history of prematurity and presence of comorbidities did not differ between the SARS-CoV-2-positive and SARS-CoV-2-negative infants. Human metapneumovirus and respiratory syncytial virus were the viruses most frequently detected in the group of infants negative for SARS-CoV-2.Infants testing positive for SARS-CoV-2 received oxygen supplementation less frequently compared with SARS-CoV-2-negative patients, 37 (39%) vs 1076 (56.4%), p=0.001, OR 0.49 (95% CI 0.32 to 0.75). They received less ventilatory support: 12 (12.6%) high flow nasal cannulae vs 468 (24.5%), p=0.01; 1 (1.0%) continuous positive airway pressure vs 125 (6.6%), p=0.03, OR 0.48 (95% CI 0.27 to 0.85).

CONCLUSIONS

SARS-CoV-2 rarely causes bronchiolitis in infants. SARS-CoV-2-related bronchiolitis mostly has a mild clinical course.

Increasing rhinovirus prevalence in paediatric intensive care patients since the SARS-CoV2 pandemic

BACKGROUND

Rhinovirus (HRV) is a significant seasonal pathogen in children. The emergence of SARS-CoV2, and the social restrictions introduced in, disrupted viral epidemiology. Here we describe the experience of Great Ormond Street Hospital (GOSH), where HRV almost entirely disappeared from the paediatric intensive care units (PICU) during the first national lockdown and then rapidly re-emerged with a fast-increasing incidence, leading to concerns about possible nosocomial transmission in a vulnerable population.

OBJECTIVES

To describe alterations in HRV infection amongst PICU patients at GOSH since the emergence of SARS-COV2 STUDY DESIGN: 10,950 nasopharyngeal aspirate viral PCR samples from GOSH PICU patients from 2019 to 2023 were included. 3083 returned a positive result for a respiratory virus, with 1530 samples positive for HRV. 66 HRV isolates from August 2020 - Jan 2021, the period of rapidly increasing HRV incidence, were sequenced. Electronic health record data was retrospectively collected for the same period.

RESULTS

Following a reduction in the incidence of HRV infection during the first national lockdown, multiple genotypes of HRV emerged amongst GOSH PICU patients, with the incidence of HRV infection rapidly surging to levels higher than that seen prior to the emergence of SARS-CoV2 and continuing to circulate at increased incidence year-round.

CONCLUSIONS

The incidence of HRV infection amongst GOSH PICU patients is markedly higher than prior to the emergence of SARS-CoV2, a pattern not seen in other respiratory viruses. The increased burden of HRV-infection in vulnerable PICU patients has both clinical and infection prevention and control Implications.

Circulation of Rhinoviruses and/or Enteroviruses in Pediatric Patients With Acute Respiratory Illness Before and During the COVID-19 Pandemic in the US

IMPORTANCE

Rhinoviruses and/or enteroviruses, which continued to circulate during the COVID-19 pandemic, are commonly detected in pediatric patients with acute respiratory illness (ARI). Yet detailed characterization of rhinovirus and/or enterovirus detection over time is limited, especially by age group and health care setting.

OBJECTIVE

To quantify and characterize rhinovirus and/or enterovirus detection before and during the COVID-19 pandemic among children and adolescents seeking medical care for ARI at emergency departments (EDs) or hospitals.

DESIGN, SETTING, AND PARTICIPANTS

This cross-sectional study used data from the New Vaccine Surveillance Network (NVSN), a multicenter, active, prospective surveillance platform, for pediatric patients who sought medical care for fever and/or respiratory symptoms at 7 EDs or hospitals within NVSN across the US between December 2016 and February 2021. Persons younger than 18 years were enrolled in NVSN, and respiratory specimens were collected and tested for multiple viruses.

MAIN OUTCOMES AND MEASURES

Proportion of patients in whom rhinovirus and/or enterovirus, or another virus, was detected by calendar month and by prepandemic (December 1, 2016, to March 11, 2020) or pandemic (March 12, 2020, to February 28, 2021) periods. Month-specific adjusted odds ratios (aORs) for rhinovirus and/or enterovirus-positive test results (among all tested) by setting (ED or inpatient) and age group (<2, 2-4, or 5-17 years) were calculated, comparing each month during the pandemic to equivalent months of previous years.

RESULTS

Of the 38 198 children and adolescents who were enrolled and tested, 11 303 (29.6%; mean [SD] age, 2.8 [3.7] years; 6733 boys [59.6%]) had rhinovirus and/or enterovirus-positive test results. In prepandemic and pandemic periods, rhinoviruses and/or enteroviruses were detected in 29.4% (9795 of 33 317) and 30.9% (1508 of 4881) of all patients who were enrolled and tested and in 42.2% (9795 of 23 236) and 73.0% (1508 of 2066) of those with test positivity for any virus, respectively. Rhinoviruses and/or enteroviruses were the most frequently detected viruses in both periods and all age groups in the ED and inpatient setting. From April to September 2020 (pandemic period), rhinoviruses and/or enteroviruses were detectable at similar or lower odds than in prepandemic years, with aORs ranging from 0.08 (95% CI, 0.04-0.19) to 0.76 (95% CI, 0.55-1.05) in the ED and 0.04 (95% CI, 0.01-0.11) to 0.71 (95% CI, 0.47-1.07) in the inpatient setting. However, unlike some other viruses, rhinoviruses and/or enteroviruses soon returned to prepandemic levels and from October 2020 to February 2021 were detected at similar or higher odds than in prepandemic months in both settings, with aORs ranging from 1.47 (95% CI, 1.12-1.93) to 3.01 (95% CI, 2.30-3.94) in the ED and 1.36 (95% CI, 1.03-1.79) to 2.44 (95% CI, 1.78-3.34) in the inpatient setting, and in all age groups. Compared with prepandemic years, during the pandemic, rhinoviruses and/or enteroviruses were detected in patients who were slightly older, although most (74.5% [1124 of 1508]) were younger than 5 years.

CONCLUSIONS AND RELEVANCE

Results of this study show that rhinoviruses and/or enteroviruses persisted and were the most common respiratory virus group detected across all pediatric age groups and in both ED and inpatient settings. Rhinoviruses and/or enteroviruses remain a leading factor in ARI health care burden, and active ARI surveillance in children and adolescents remains critical for defining the health care burden of respiratory viruses.

Effects of air pollution and weather on the initial COVID-19 outbreaks in United States, Italy, Spain, and China: A comparative study

Contrasting effects have been identified in association of weather (temperature and humidity) and pollutant gases with COVID-19 infection, which could be derived from the influence of lockdowns and season change. The influence of pollutant gases and climate during the initial phases of the pandemic, before the closures and the change of season in the northern hemisphere, is unknown. Here, we used a spatial-temporal Bayesian zero-inflated-Poisson model to test for short-term associations of weather and pollutant gases with the relative risk of COVID-19 disease in China (first outbreak) and the countries with more cases during the initial pandemic (the United States, Spain and Italy), considering also the effects of season and lockdown. We found contrasting association between pollutant gases and COVID-19 risk in the United States, Italy, and Spain, while in China it was negatively associated (except for SO₂ ). COVID-19 risk was positively associated with specific humidity in all countries, while temperature presented a negative effect. Our findings showed that short-term associations of air pollutants with COVID-19 infection vary strongly between countries, while generalized effects of temperature (negative) and humidity (positive) with COVID-19 was found. Our results show novel information about the influence of pollution and weather on the initial outbreaks, which contribute to unravel the mechanisms during the beginning of the pandemic.

Changing Epidemiology of Acute Viral Respiratory Infections in Hospitalized Children: The Post-Lockdown Effect

Several reports highlighted how public health measures aimed at limiting severe acute respiratory syndrome Coronavirus-2 (SARS-CoV-2) circulation have likely contributed to reducing the circulation of other respiratory viruses, particularly during the first year of the COVID-19 pandemic. We evaluated the epidemiology of acute respiratory infections in a large cohort of hospitalized children during the third year of the pandemic (2021−2022). We retrospectively analyzed data from the health records of children (<14 years) hospitalized for acute respiratory infections between 1 July 2021 and 31 March 2022. A total of 1763 respiratory panels were collected. Overall, 1269 (72%) panels hadpositive results for at least one pathogen. Most positive panels (53.8%) belonged to patients aged 1−12 months. The most detected pathogen was respiratory syncytial virus (RSV) (57.8% of positive panels). The RSV peak occurred in November 2021. Nine hundred and forty-five (74.5%) panels were positive for one pathogen while three hundred and twenty-four (25.5%) showed multiple infections. Patients with multiple infections were significantly older than those with a single infection. The 2021−2022 peak of RSV infection in Italy occurred earlier than in the previous pre-pandemic seasons. A high number of children have been hospitalized because of acute viral infections also due to less aggressive viruses.

Prevalence of SARS-CoV-2 positivity in infants with bronchiolitis: a multicentre international study

BACKGROUND

Bronchiolitis is the leading acute respiratory tract infection in infants during the winter season. Since the beginning of the SARS-CoV-2 pandemic, a reduction in the number of bronchiolitis diagnoses has been registered.

OBJECTIVE

The present study aimed to describe the incidence and clinical features of bronchiolitis during the 2020-2021 winter season in a large cohort of children in Europe and Israel, and to clarify the role of SARS-CoV-2.

SETTING, PATIENTS, INTERVENTIONS

We conducted a multicentre observational cross-sectional study in 23 paediatric emergency departments in Europe and Israel. Clinical and demographic data about all the cases of infants diagnosed with bronchiolitis from 1 October 2020 to 30 April 2021 were collected. For each enrolled patient, diagnostic tests, treatments and outcomes were reported.

MAIN OUTCOME MEASURES

The main outcome was the prevalence of SARS-CoV-2-positive bronchiolitis.

RESULTS

Three hundred and fourteen infants received a diagnosis of bronchiolitis during the study period. Among 535 infants who tested positive for SARS-CoV-2, 16 (3%) had bronchiolitis. Median age, male sex predominance, weight, history of prematurity and presence of comorbidities did not differ between the SARS-CoV-2-positive and SARS-CoV-2-negative groups. Rhinovirus was the most common involved pathogen, while respiratory syncytial virus (RSV) was detected in one case. SARS-CoV-2 bronchiolitis had a mild clinical course, with one patient receiving oxygen supplementation and none requiring paediatric or neonatal intensive care unit admission.

CONCLUSIONS

During the SARS-CoV-2 pandemic, a marked decrease in the number of bronchiolitis diagnoses and the disappearance of the RSV winter epidemic were observed. SARS-CoV-2-related bronchiolitis was rare and mostly displayed a mild clinical course.

Reduction and persistence of co-circulating respiratory viruses during the SARS-CoV-2 pandemic

To evaluate co-circulation of respiratory viruses during the SARS-CoV-2 Alpha surge, we performed a molecular respiratory panel on 1,783 nasopharyngeal swabs collected between January 15 and April 15, 2021 from symptomatic outpatients that tested negative for SARS-CoV-2 in North Carolina. Of these, 373 (20.9%) were positive for at least one virus tested on the panel. Among positive tests, over 90% were positive for rhinovirus/enterovirus, either as a single infection or coinfection, illustrating persistent co-circulation of some respiratory viruses despite active infection control measures.

The first winter of social distancing improved most of the health indexes in a paediatric emergency department

Aim

We compared visits to a tertiary level paediatric emergency department (PED) in Italy, during winter 2020–2021, when COVID‐19 social distancing measures were in place, with winter 2019–2020.

Methods

This was a retrospective analysis of an electronic database. We obtained the number of visits and the ages, main complaints, triage codes, discharge diagnoses and outcomes of patients who accessed the PED from the 1 October 2020 to 28 February 2021. These were compared to the same period in 2019–2021.

Results

Visits fell by 52%, from 10982 in 2019–2020 to 5317 in 2020–2021 (p < 0.0001). The reductions were 52% in neonates, 58% in infants, 53% in toddlers, 61% in preschool children, 48% in school children and 46% in adolescents. Non‐urgent and urgent triage codes declined. Respiratory and gastrointestinal infections fell by 72% and 71% respectively. Injuries declined by 42%, mainly among adolescents. Accidental intoxication, psychiatric symptoms and substance or alcohol abuse declined by 24%, 33% and 64%. Hospital admissions reduced by 8% and admissions to intensive care fell by 29%.

Conclusion

During the first winter of pandemic social distancing visits to an Italian PED fell by 52%, with higher reductions in younger children and infants, and hospital admissions fell by 8%.

Clinical, anamnestic, and sociodemographic predictors of positive SARS-CoV-2 testing in children: A cross sectional study in a tertiary hospital in Italy

OBJECTIVES

We aimed to identify clinical, anamnestic, and sociodemographic characteristics associated with a positive swab for SARS-CoV2, and to provide a predictive score to identify at risk population in children aged 2-14 years attending school and tested for clinical symptoms of COVID-19.

DESIGN

Cross sectional study.

SETTING

Outpatient clinic of the IRCCS Burlo Garofolo, a maternal and child health tertiary care hospital and research centre in Italy.

DATA COLLECTION AND ANALYSIS

Data were collected through a predefined form, filled out by parents, and gathered information on sociodemographic characteristics, and specific symptoms, which were analysed to determine their association with a positive SARS-CoV-2 swab. The regression coefficients of the variables included in the multivariate analysis were further used in the calculation of a predictive score of the positive or negative test.

RESULTS

Between September 20th and December 23rd 2020, from 1484 children included in the study, 127 (8.6%) tested positive. In the multivariate analysis, the variables retained by the model were the presence of contact with a cohabiting, non-cohabiting or unspecified symptomatic case (respectively OR 37.2, 95% CI 20.1-68.7; 5.1, 95% CI 2.7-9.6; 15.6, 95% CI 7.3-33.2); female sex (OR 1.49, 95% CI 1.0-2.3); age (6-10 years old: OR 3.2, 95% CI 1.7-6.1 p<0.001; >10 years old: OR 4.8, 95% CI 2.7-8.8 p<0.001); fever (OR 3.9, 95% CI 2.3-6.4); chills (OR 1.9, 95% CI 1.1-3.3); headache (OR 1.45, 95% CI 0.9-2.4); ageusia (OR 1.3, 95% CI 0.5-4.0); sore throat (OR 0.48, 95% CI 0.3-0.8); earache (OR 0.4, 95% CI 0.1-1.3); rhinorrhoea (OR 0.8, 95% CI 0.5-1.3); and diarrhoea (OR 0.52, 95% CI 0.2-1.1). The predictive score based on these variables generated 93% sensitivity and 99% negative predictive value.

CONCLUSIONS

The timely identification of SARS-CoV2 cases among children is useful to reduce the dissemination of the disease and its related burden. The predictive score may be adopted in a public health perspective to rapidly identify at risk children.

Pediatric Emergency Cases in the First Year of the COVID-19 Pandemic in a Tertiary-Level Emergency Setting

AIM

Emergency cases are uncommon events in the pediatric emergency setting. This study aimed to evaluate the effect of the Coronavirus disease 2019 (COVID-19) pandemic by describing the number and type of pediatric emergency cases that arrived at the pediatric emergency department (PED) of a tertiary-level children's hospital in Italy.

METHODS

We performed a retrospective study, collecting the main features of pediatric emergency patients who arrived during the first year of the COVID-19 pandemic (March 2020-February 2021) compared to the pre-pandemic period (March 2016-February 2020).

RESULTS

During the study period, 112,168 patients were visited at the PED, and 237 (0.21%) were emergency cases, median age of 4 years (IQR: 1-12). In the first year of the pandemic, 42 children were coded as emergency cases compared to 195 (49/year) during the pre-pandemic period. The proportion of emergency cases was stable (0.27% during the COVID-19 period versus 0.20% during the pre-COVID-19 period, p = 0.19). No differences were found regarding the age, gender, hour of arrival, and outcome of patients. We found a significant decrease in the proportion of emergency cases related to respiratory diseases (9/42, 21.4% during the COVID-19 period versus 83/195 during the pre-COVID-19 period (42.6%), p = 0.01).

CONCLUSION

In conclusion, our data suggest that the pandemic had a more significant impact on respiratory emergency cases than on pediatric emergencies in general.

Rhinovirus spread in children during the COVID-19 pandemic despite social restrictions-A nationwide register study in Finland

Social restrictions during the coronavirus disease 2019 pandemic strongly affected the epidemiology of influenza and respiratory syncytial virus (RSV). As rhinovirus seemed to spread despite the restrictions, we aimed to analyze rhinovirus epidemiology in children during the pandemic. This register‐based study used data from the Finnish Infectious Disease Register. Nationwide rhinovirus findings from July 2015 to March 2021 were included and stratified by age (0–4, 5–9, and 10–14). Cumulative 14‐day incidence per 100000 children was calculated. Four thousand five hundred and seventy six positive rhinovirus findings were included, of which 3788 (82.8%) were among children aged 0–4. The highest recorded incidence was 36.2 among children aged 0–4 in October 2017. The highest recorded incidence during the pandemic period was 13.6 in November 2020. The impact of the restrictions was mostly seen among children aged 0–4 years of age in weeks 14–22 in 2020. The incidence has since remained near reference levels in all age groups. Strict restrictions temporarily interrupted the circulation of rhinovirus in spring 2020. Rhinovirus incidence returned to normal levels soon after the harsh restrictions were lifted. These looser social restrictions prevented RSV and influenza seasons but failed to prevent the spread of rhinovirus.

Disappearance of Seasonal Respiratory Viruses in Children Under Two Years Old During COVID-19 Pandemic: A Monocentric Retrospective Study in Milan, Italy

Background: The containment measures adopted during COVID-19 pandemic have influenced the epidemiology of other respiratory viruses. Aim: We analyzed the modification of the incidence and etiology of lower respiratory tract infections (LRTIs) in young children during COVID-19 pandemic. Methods: Case series of all children under 2 years old hospitalized at a tertiary care Hospital in the Center of Milan, Italy diagnosed with LRTIs in three consecutive winter seasons (from the 1st of November to the last day of February in 2018/2019, 2019/2020 and 2020/2021). We compared the number of hospitalizations and viral detections in the 2020/2021 with the average of 2018/2019 and 2019/2020 (pre-COVID-19) using the Poisson distribution. Results: we enrolled 178 patients (66 from 2018/2019, 96 from 2019/2020, 16 from 2020/2021) 94 males (53%) and 84 females (47%), with a median (IQR) age of 5 (2-13) months. The number of hospitalizations during the 2020/2021 season was 80% lower than the average of the pre-COVID-19 seasons (16 vs. 81, p<0.001). Overall, 171 (96%) patient's nasopharyngeal aspirate (NPA) detected at least one virus (110, 64%, single-detection, 61, 36%, co-detections). In 2020/2021 we observed the disappearance of Respiratory Syncytial virus (0 vs. 54, p < 0.001), Influenza virus (0 vs. 6.5, p = 0.002), Metapneumovirus (0 vs. 8, p < 0.001), Parainfluenza viruses (0 vs. 3.5, p = 0.03) and a significant reduction of Adenovirus (2 vs. 7, p = 0.03), Bocavirus (2 vs. 7.5, p = 0.02) and Enterovirus (1 vs. 5, p = 0.04). No significant difference was found for Rhinoviruses (14 cases vs. 17, p = 0.2), other Coronaviruses (0 vs. 2, p = 0.1), and Cytomegalovirus (1 vs. 1, p = 0.7). Conclusions: We observed a striking reduction in hospitalizations due to LRTIs and a modification of the etiology, with enveloped viruses mainly affected.