Trends in childhood asthma in Denmark, Finland, Norway and Sweden.

Aim: Estimate the incidence of asthma among children aged 0 to 15 years in Denmark, Finland, Norway and Sweden during 2000-2017.

Methods: Cases of preschool asthma (up to 6 years) and school-age asthma (from 6 years) were identified through national registers using an algorithm including hospital diagnoses and prescription medicines. The respective cumulative incidence (CI) was estimated in 1-year age intervals for each country and birth year.

Vaccination against measles-mumps-rubella and rates of non-targeted infectious disease hospitalisations: Nationwide register-based cohort studies in Denmark, Finland, Norway, and Sweden.

Objectives: To investigate if receipt of measles-mumps-rubella (MMR) vaccine following the third dose of diphtheria-tetanus-acellular pertussis (DTaP3) is associated with reduced rates of non-targeted infectious disease hospitalisations.

Methods: Register based cohort study following 1,397,027 children born in Denmark, Finland, Norway, and Sweden until 2 years of age. Rates of infectious disease hospitalisations with minimum one overnight stay according to time-varying vaccination status were compared using Cox proportional hazards regression analysis with age as the underlying timescale and including multiple covariates.

Post-COVID symptoms after SARS-CoV-2 omicron infection and the effect of booster vaccination: A population-based cohort study.

Background: The impact of vaccination on the type and risk of specific post-COVID symptoms after Omicron infection is not clear. We aimed to investigate the excess risk and patterns of 22 symptoms 3-5 months after Omicron infection, comparing uninfected and infected subjects with and without recent booster vaccination.

Methods: We conducted a population-based prospective study based on four questionnaire-based cohorts linked to national health registries.

Infectious disease hospitalization after receipt of human papillomavirus vaccine: a nationwide register-based cohort study among Danish, Finnish, Norwegian, and Swedish girls.

It has been suggested that non-live vaccines may increase susceptibility to non-targeted infections and that such deleterious non-specific effects are more pronounced in girls. We investigated whether receipt of non-live vaccine against human papillomavirus (HPV) was associated with increased risk of infectious disease hospitalization. A nationwide cohort study based on detailed individual-level data from national registries was performed in Denmark, Finland, Norway, and Sweden.

Saturated fatty acids and total and CVD mortality in Norway: a prospective cohort study with up to 45 years of follow-up.

The contribution of dietary saturated fatty acids (SFA) to cardiovascular disease (CVD) and mortality remains debated after decades of research. Few previous studies had repeated dietary assessments and power to assess mortality. Evidence for individual SFA is limited.

Potato Consumption and All-Cause and Cardiovascular Disease Mortality - A Long-Term Follow-Up of a Norwegian Cohort.

Background: Potatoes are a staple food in many traditional cuisines, yet their impact on long-term risk of cardiovascular disease (CVD) and mortality is unclear, hampering evidence-based dietary guidelines.

Objectives: This study aimed to examine the association between potato consumption and all-cause and CVD-specific death over a substantial follow-up period within a cohort predominantly consuming boiled potatoes.

Methods: Adults from 3 Norwegian counties were invited to 3 health screenings in 1974-1988 (>80% attendance).

Higher educational attainment associated with higher confidence in influenza vaccination in Norway.

Aims: To explore public confidence in influenza vaccination through the use of attitudinal indicators, and study whether educational attainment is related to attitudes towards influenza vaccination.

Methods: Confidence in influenza vaccination was measured with three questions adapted from the Vaccine Confidence Project. These questions have been included in four study years of a Norwegian nationally representative telephone survey that cover influenza seasons 2016/17, 2019/20, 2020/21 and 2021/22.

Is vaccination against measles, mumps, and rubella associated with reduced rates of antibiotic treatments among children below the age of 2 years? Nationwide register-based study from Denmark, Finland, Norway, and Sweden.

Objectives: Previous studies have shown that vaccination against measles, mumps, and rubella (MMR) may have beneficial non-specific effects, reducing the risk of infections not targeted by the vaccine. We investigated if MMR vaccine given after the third dose of diphtheria-tetanus-acellular pertussis vaccine (DTaP3), was associated with reduced rates of antibiotic treatments.

Methods: Register-based cohort study following children from the age of recommended MMR vaccination until age 2 years.

Unexpected vaginal bleeding and COVID-19 vaccination in nonmenstruating women.

The association between coronavirus disease 2019 (COVID-19) vaccination and vaginal bleeding among nonmenstruating women is not well studied. The Norwegian Institute of Public Health followed several cohorts throughout the pandemic and early performed a systematic data collection of self-reported unexpected vaginal bleeding in nonmenstruating women. Among 7725 postmenopausal women, 7148 perimenopausal women, and 7052 premenopausal women, 3.

Antibodies against Neisseria meningitidis serogroups A, C, W and Y in serum and saliva of Norwegian adolescents.

Introduction: The incidence of invasive meningococcal disease (IMD) among Norwegian 16-19-year-olds was 1-7/100,000 in the decade before the COVID-19 pandemic, with serogroup Y (MenY) dominance. In contrast to many other European countries, meningococcal vaccines are not part of the national immunisation program (NIP) in Norway. This cross-sectional study aimed to measure the degree of natural immunity against Neisseria meningitidis among adolescents in Norway to evaluate the need for introducing tetravalent meningococcal conjugate vaccine (MCV4) in the NIP.

Heavy bleeding and other menstrual disturbances in young women after COVID-19 vaccination.

Background: Many signals of menstrual disturbances as possible side effects of vaccination against COVID-19 have been reported. Our objective was to compare the risk of menstrual disturbances before and after vaccination among women aged 18-30 years in Oslo, Norway.

Methods: We used electronic questionnaires to collect reports of menstrual disturbances from 3972 women aged 18-30 years, participating in the population-based Norwegian Young Adult Cohort.

Cohort Profile: Childhood morbidity and potential non-specific effects of the childhood vaccination programmes in the Nordic countries (NONSEnse): register-based cohort of children born 1990-2017/2018.

Purpose: The aim of the NONSEnse project is to investigate the non-specific effects of vaccines and immunisation programmes on the overall health of children by using information from the extensive nationwide registers on health and sociodemographic factors in Denmark, Finland, Norway and Sweden.

Participants: The cohort covers 9 072 420 children aged 0-17 years, born 1990-2017/2018 and living in Denmark, Finland, Norway or Sweden. All countries use a unique identification number for its permanent residents, which makes it possible to link individual-level information from different registers.

Social and demographic patterns of influenza vaccination coverage in Norway, influenza seasons 2014/15 to 2020/21.

Aims: To examine influenza vaccination coverage among risk groups (RG) and health care workers (HCW), and study social and demographic patterns of vaccination coverage over time.

Methods: Vaccination coverage was estimated by self-report in a nationally representative telephone survey among 14919 individuals aged 18-79 years over seven influenza seasons from 2014/15 to 2020/21. We explored whether belonging to an influenza RG (being >=65 years of age and/or having >=1 medical risk factor), being a HCW or educational attainment was associated with vaccination status using logistic regression.

Effectiveness of mRNA Booster Vaccination Against Mild, Moderate, and Severe COVID-19 Caused by the Omicron Variant in a Large, Population-Based, Norwegian Cohort.

Background: Understanding how booster vaccination can prevent moderate and severe illness without hospitalization is crucial to evaluate the full advantage of mRNA boosters.

Methods: We followed 85 801 participants (aged 31-81 years) in 2 large population-based cohorts during the Omicron BA.1/2 wave.

FLU-v, a Broad-Spectrum Influenza Vaccine, Induces Cross-Reactive Cellular Immune Responses in Humans Measured by Dual IFN-γ and Granzyme B ELISpot Assay.

Previous reports demonstrated that FLU-v, a peptide-based broad-spectrum influenza vaccine candidate, induced antibody and cellular immune responses in humans. Here, we evaluate cellular effector functions and cross-reactivity. PBMC sampled pre- (day 0) and post-vaccination (days 42 and 180) from vaccine (n = 58) and placebo (n = 27) recipients were tested in vitro for responses to FLU-v and inactivated influenza strains (A/H3N2, A/H1N1, A/H5N1, A/H7N9, B/Yamagata) using IFN-γ and granzyme B ELISpot.

Trends in Antibiotic Use in Danish, Finnish, Norwegian and Swedish Children.

Objective: To compare the use of antibiotics in children in four Northern European countries.

Methods: We conducted a register-based study based on individual-level prescription data from national prescription registers. We identified all redeemed outpatient prescriptions for systemic antibiotics in children aged 0-14 years from July 2006 to June 2017 in Denmark, Finland, Norway, and Sweden.

Hospital Contacts for Infectious Diseases Among Children in Denmark, Finland, Norway, and Sweden, 2008-2017.

Purpose: Comparing rates of childhood infectious disease hospitalisations across countries may uncover areas for improvement in the prevention of severe childhood infections. We compared rates of childhood infectious disease hospital contacts across Denmark, Finland, Norway, and Sweden with the overall objective to elucidate potential differences in burden of disease and in organisational and registration practices.

Methods: Using national registries, we estimated incidence rates for infectious disease hospital contacts between 2008 and 2017 among children aged 0-14 years.

Influenza risk groups in Norway by education and employment status.

Aims: This study aimed to estimate the size of the risk group for severe influenza and to describe the social patterning of the influenza risk group in Norway, defined as everyone ⩾65 years of age and individuals of any age with certain chronic conditions (medical risk group).

Methods: Study data came from a nationally representative survey among 10,923 individuals aged 16-79 years. The medical risk group was defined as individuals reporting one or more relevant chronic conditions.

Household Transmission of SARS-CoV-2: A Prospective Longitudinal Study Showing Higher Viral Load and Increased Transmissibility of the Alpha Variant Compared to Previous Strains.

We studied the secondary attack rate (SAR), risk factors, and precautionary practices of household transmission in a prospective, longitudinal study. We further compared transmission between the Alpha (B.1.

Safety of Influenza A H1N1pdm09 Vaccines: An Overview of Systematic Reviews.

Background: In 2009, a new influenza A H1N1 virus emerged causing a global pandemic. A range of monovalent influenza A H1N1pdm09 vaccines with or without adjuvants were developed. After the mass vaccination campaigns safety concerns related to H1N1pdm09 vaccines were reported.

Time trends in HPV vaccination according to country background: a nationwide register-based study among girls in Norway.

Background: Since the human papillomavirus (HPV) vaccine was introduced in Norway in 2009, the vaccine uptake has increased. Whether this increase is similar regardless of the girls' country background is unknown. We examined changes in HPV vaccine uptake from 2009 to 2014 and studied the impact of parental education and income on HPV vaccine uptake according to country background.