Age-specific SARS-CoV-2 transmission differed from human rhinovirus in households during the early COVID-19 pandemic.

Objectives: Children are generally considered main drivers of transmission for respiratory viruses, but the emergence of SARS-CoV-2 challenged this paradigm. Human rhinovirus (RV) continued to co-circulate throughout the pandemic, allowing for direct comparison of age-specific infectivity and susceptibility within households between these viruses during a time of low SARS-CoV-2 population immunity.

Methods: Households with children were prospectively monitored for ≥23 weeks between August 2020 and July 2021.

Influenza Infection and Acute Myocardial Infarction.

Background: Acute respiratory infections can trigger acute myocardial infarction. We aimed to quantify the association between laboratory-confirmed influenza infection and acute myocardial infarction, particularly in patients with and without known coronary artery disease.

Methods: This observational, registry-based, self-controlled case series study evaluated the association between laboratory-confirmed influenza infection and occurrence of acute myocardial infarction.

Addressing current limitations of household transmission studies by collecting contact data.

Modeling studies of household transmission data have helped characterize the role of children in influenza and coronavirus disease 2019 (COVID-19) epidemics. However, estimates from these studies may be biased since they do not account for the heterogeneous nature of household contacts. Here, we quantified the impact of contact heterogeneity between household members on the estimation of child relative susceptibility and infectivity.

Estimation of introduction and transmission rates of SARS-CoV-2 in a prospective household study.

Household studies provide an efficient means to study transmission of infectious diseases, enabling estimation of susceptibility and infectivity by person-type. A main inclusion criterion in such studies is usually the presence of an infected person. This precludes estimation of the hazards of pathogen introduction into the household.

Estimation of introduction and transmission rates of SARS-CoV-2 in a prospective household study.

Household studies provide an efficient means to study transmission of infectious diseases, enabling estimation of individual susceptibility and infectivity. A main inclusion criterion in such studies is often the presence of an infected person. This precludes estimation of the hazards of pathogen introduction into the household.

SARS-CoV-2 outbreaks in secondary school settings in the Netherlands during fall 2020; silent circulation.

Background: In fall 2020 when schools in the Netherlands operated under a limited set of COVID-19 measures, we conducted outbreaks studies in four secondary schools to gain insight in the level of school transmission and the role of SARS-CoV-2 transmission via air and surfaces.

Methods: Outbreak studies were performed between 11 November and 15 December 2020 when the wild-type variant of SARS-CoV-2 was dominant. Clusters of SARS-CoV-2 infections within schools were identified through a prospective school surveillance study.

The impact of variant and vaccination on SARS-CoV-2 symptomatology; three prospective household cohorts.

Objectives: We compared age-stratified SARS-CoV-2 symptomatology of wild-type/Alpha vs Omicron BA.1/BA.2 variant infected individuals and the impact of COVID-19 booster vaccination on Omicron symptom burden.

Longitudinal Household Assessment of Respiratory Illness in Children and Parents During the COVID-19 Pandemic.

Importance: In the early COVID-19 pandemic, SARS-CoV-2 testing was only accessible and recommended for symptomatic persons or adults. This restriction hampered assessment of the true incidence of SARS-CoV-2 infection in children as well as detailed characterization of the SARS-CoV-2 disease spectrum and how this spectrum compared with that of other common respiratory illnesses.

Objective: To estimate the community incidence of SARS-CoV-2 infection in children and parents and to assess the symptoms and symptom severity of respiratory illness episodes involving SARS-CoV-2-positive test results relative to those with SARS-CoV-2-negative test results.

Detection of Potential Arbovirus Infections and Pregnancy Complications in Pregnant Women in Jamaica Using a Smartphone App (ZIKApp): Pilot Evaluation Study.

Background: There is growing evidence of the benefits of mobile health technology, which include symptom tracking apps for research, surveillance, and prevention. No study has yet addressed arbovirus symptom tracking in pregnancy.

Objective: This study aimed to evaluate the use of a smartphone app (ZIKApp) to self-report arbovirus symptoms and pregnancy complications and to assess compliance with daily symptom diaries during pregnancy in a cohort of women in an arbovirus-endemic, subtropical, middle-income country (Jamaica).

Impact of 7-valent versus 10-valent pneumococcal conjugate vaccines on primary care consultations across various age groups in the Netherlands, 5 years after the switch: A time-series analysis.

Background: In 2011, 10-valent pneumococcal conjugate vaccine (PCV10) replaced PCV7 in The Netherlands. We aimed to assess the impact of this switch on non-invasive pneumococcal disease in primary care across various age-groups, including pneumonia-bronchitis, otitis media (OM) and sinusitis with and without considering pre-PCV10 secular trends.

Methods: Electronic records of 397,441 individuals included in a regional primary care database from July 2006 to June 2016 were extracted (2,408,762 person-years).

Faecal Inflammatory Biomarkers and Gastrointestinal Symptoms after Bariatric Surgery: A Longitudinal Study.

Background: Bariatric surgery induces various gastrointestinal (GI) modifications. We performed the first study longitudinally assessing the effect of bariatric surgery on faecal inflammatory biomarker levels and its relation with GI complaints.

Method: Faecal calprotectin, lactoferrin, and calgranulin-C levels were determined in 41 patients (34 Roux-en-Y [RYGB], 7 sleeves) before and at 6-16 weeks, 6 months, and 1 year after surgery.

Experiences and needs of persons living with a household member infected with SARS-CoV-2: A mixed method study.

Background: Households are important sites for transmission of SARS-CoV-2 and preventive measures are recommended. This study aimed to 1) investigate the impact of living with a person infected with SARS-CoV-2; 2) understand how household members implemented infection control recommendations in their home; and 3) identify the information and support needs of household members.

Methods: For this observational mixed-methods study, households with a person with confirmed SARS-CoV-2 infection were recruited via drive-through testing sites of Municipal Health Services, healthcare worker screening or hospital emergency visits in the University Medical Centre Utrecht, the Netherlands and via primary care physicians, hospital emergency visits or preoperative screening in the University Hospital of Antwerp, Belgium.

Mental Well-being and General Health in Adolescents with Asthma: The Prevention and Incidence of Asthma and Mite Allergy Birth Cohort Study.

Objectives: To assess whether adolescents with asthma experience a lower mental well-being and lower general health than their peers without asthma.

Study Design: Data from the Prevention and Incidence of Asthma and Mite Allergy study were used. At the ages of 11, 14, 17, and 20 years, 2651, 2522, 2094, and 2206 participants, respectively, completed questionnaires.

Defining asthma in children: how well do parents, doctors and spirometry agree?

Background: Because diagnosing asthma in school-aged children is challenging, a variety of proxies for asthma are used in clinical practice and research settings as indicators of this disease. We aimed to provide insight into the agreement between various asthma indicators based on parental report, medical diagnosis and spirometry.

Methods: Children from the WHISTLER birth cohort performed spirometry and were followed up with parental ISAAC (International Study of Asthma and Allergies in Childhood) questionnaires about asthma at 5 and 8 years of age.

Cost-effectiveness of inactivated influenza vaccination in children with medical risk conditions in the Netherlands.

Background: In many countries, annual immunization with inactivated influenza vaccine (IIV) is recommended for children with medical risk conditions. Prior cost-effectiveness analyses found such immunization to be cost saving, but assumed effectiveness against non-severe influenza outcomes and a higher effectiveness against severe influenza outcomes than recent studies would suggest. However, recent vaccine studies do not indicate any reduction in community or outpatient disease episodes in IIV immunized individuals.

Community burden and transmission of acute gastroenteritis caused by norovirus and rotavirus in the Netherlands (RotaFam): a prospective household-based cohort study.

Background: Norovirus and rotavirus are the dominant pathogens causing acute gastroenteritis in children. To quantify their natural disease burden and transmission, we prospectively monitored households in an endemic setting in the Netherlands, a high-income country that does not have a rotavirus vaccination programme.

Methods: We did a prospective, household survey-based cohort study in the Netherlands.

Inactivated influenza vaccine does not reduce all cause respiratory illness in children with pre-existing medical conditions.

Background: The effectiveness of inactivated influenza vaccine (IIV) immunization in preventing all cause respiratory illness (RI) in children with pre-existing medical conditions has not been fully established and varies from season to season. This study aims to quantify the overall impact of IIV immunization on primary care attended RI episodes in children with pre-existing medical conditions, using robust observational data spanning twelve influenza seasons.

Methods: Electronic records of IIV eligible children aged 6 months to 18 years were extracted from primary care databases over the years 2004-2015.

Impact of Repeated Influenza Immunization on Respiratory Illness in Children With Preexisting Medical Conditions.

Purpose: Annual influenza immunization in medical risk groups is recommended in many countries. Recent evidence suggests that repeated inactivated influenza vaccine (IIV) immunization throughout childhood may impair long-term immunity against influenza. We assessed whether prior immunization altered the effect of IIV in children with preexisting medical conditions on primary care-diagnosed respiratory illness (RI) episodes during the influenza season.

Impact of acute otitis media clinical practice guidelines on antibiotic and analgesic prescriptions: a systematic review.

Background: Clinical practice guidelines focusing on judicious use of antibiotics for childhood acute otitis media (AOM) have been introduced in many countries around the world.

Objective: To systematically review the effects of these guidelines on the prescription of antibiotics and analgesics for children with AOM.

Methods: Systematic searches of PubMed, Embase and Cochrane Library from inception to 6 June 2017 using broad search terms.

Report of the 5th European expert meeting on rotavirus vaccination (EEROVAC).

The Fifth European Expert Meeting on Rotavirus Vaccination was convened in Utrecht, The Netherlands, in March 2017. The 2-day meeting included invited lectures as well as original oral and poster presentations and brought together experts from 21 countries. Summary findings of the meeting include: Rotavirus vaccination programmes in Europe have resulted in reductions of 60-90% in rotavirus outpatient visits and hospitalizations.

Detecting Acute Otitis Media Symptom Episodes Using a Mobile App: Cohort Study.

Background: Population cohort studies are useful to study infectious diseases episodes not attended by health care services, but conventional paper diaries and questionnaires to capture cases are prone to noncompliance and recall bias. Use of smart technology in this setting may improve case finding.

Objective: The objective of our study was to validate an interactive mobile app for monitoring occurrence of acute infectious diseases episodes in individuals, independent of health care seeking, using acute otitis media (AOM) symptom episodes in infants as a case study.

Acute Otitis Media During Infancy: Parent-reported Incidence and Modifiable Risk Factors.

Background: Age at exposure to acute otitis media (AOM) risk factors such as day care attendance, lack of breastfeeding and tobacco smoke is little studied but important for targeting AOM prevention strategies. Moreover, studies are typically restricted to clinically diagnosed AOM, while a significant subset can occur outside the health care system, depending on the country setting. This study aims to determine risk factor exposure and effect of its timing within the first year of life on parent-reported AOM symptom episodes.

Antibiotic Treatment for First Episode of Acute Otitis Media Is Not Associated with Future Recurrences.

Objective: Antibiotic treatment of acute otitis media (AOM) has been suggested to increase the risk of future AOM episodes by causing unfavorable shifts in microbial flora. Because current evidence on this topic is inconclusive and long-term follow-up data are scarce, we wanted to estimate the effect of antibiotic treatment for a first AOM episode occurring during infancy on AOM recurrences and AOM-related health care utilization later in life.

Methods: We obtained demographic information and risk factors from data of the Wheezing Illnesses Study Leidsche Rijn, a prospective birth cohort study in which all healthy newborns born in Leidsche Rijn (between 2001 and 2012), The Netherlands, were enrolled.

Impact of Early-Onset Acute Otitis Media on Multiple Recurrences and Associated Health Care Use.

Objective: To quantify the critical age period of first episode of acute otitis media (AOM) and its consequences for AOM recurrences and AOM health care use.

Study Design: Children enrolled in the Wheezing-Illnesses-STudy-LEidsche-Rijn cohort with at least 1 episode of AOM documented in their primary care health record before 2 years of age were followed until 6 years of age. Data on episodes of AOM and associated primary care consultations, antibiotic prescriptions, and specialist referrals were retrieved.