Modeling geographic vaccination strategies for COVID-19 in Norway.

Vaccination was a key intervention in controlling the COVID-19 pandemic globally. In early 2021, Norway faced significant regional variations in COVID-19 incidence and prevalence, with large differences in population density, necessitating efficient vaccine allocation to reduce infections and severe outcomes. This study explored alternative vaccination strategies to minimize health outcomes (infections, hospitalizations, ICU admissions, deaths) by varying regions prioritized, extra doses prioritized, and implementation start time.

No evidence for added value of introducing mandatory COVID-19 testing for international travellers entering Norway with a valid EU digital COVID certificate.

Background: As a response to the emergence of the new Omicron SARS-CoV-2 variant, on December 3, 2021, mandatory testing after entry to Norway was extended to include international travellers with a valid COVID-19 certificate. We aim to validate if mandatory testing upon arrival increased the proportion of travellers confirmed with a positive COVID-19 test after entry.

Methods: We used individual level data on registered travellers linked with data on COVID-19 testing and confirmed COVID-19 cases.

SARS-CoV-2 infections and hospitalisations among immigrants in Norway-significance of occupation, household crowding, education, household income and medical risk: a nationwide register study.

Background: As in other countries, the COVID-19 pandemic has affected Norway's immigrant population disproportionately, with significantly higher infection rates and hospitalisations. The reasons for this are uncertain.

Methods: Through the national emergency preparedness register, BeredtC19, we have studied laboratory-confirmed infections with SARS-CoV-2 and related hospitalisations in the entire Norwegian population, by birth-country background for the period 15 June 2020 to 31 March 2021, excluding the first wave due to limited test capacity and restrictive test criteria.

Increased transmissibility of the alpha SARS-CoV-2 variant: evidence from contact tracing data in Oslo, January to February 2021.

Background: Information about the contagiousness of new SARS-CoV-2 variants, including the alpha lineage, and how they spread in various locations is essential. Country-specific estimates are needed because local interventions influence transmissibility.

Methods: We analysed contact tracing data from Oslo municipality, reported from January through February 2021, when the alpha lineage became predominant in Norway and estimated the relative transmissibility of the alpha lineage with the use of Poisson regression.

Campylobacter infections expected to increase due to climate change in Northern Europe.

Global climate change is predicted to alter precipitation and temperature patterns across the world, affecting a range of infectious diseases and particularly foodborne infections such as Campylobacter. In this study, we used national surveillance data to analyse the relationship between climate and campylobacteriosis in Denmark, Finland, Norway and Sweden and estimate the impact of climate changes on future disease patterns. We show that Campylobacter incidences are linked to increases in temperature and especially precipitation in the week before illness, suggesting a non-food transmission route.

Campylobacteriosis in the Nordic countries from 2000 to 2015: Trends in time and space.

This study aimed to describe the demographic and geographic patterns of campylobacteriosis in Denmark, Finland, Norway and Sweden during 2000-2015. All infections notified to national authorities in the four countries during the study period were included. Background data for each notification consisted of patient age, sex, geographical location, presumed origin of infection and date of sample taken or date of sample received in the laboratory.