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. The proportions of confirmed cases among international travellers before and after the requirement were introduced was analysed with an interrupted times series design. RESULTS: The proportion of travellers with an EU COVID-19 certificate tested at an official test station increased from 3% to 43% after mandatory testing was introduced. However, the proportion of all travellers confirmed with COVID-19 rose only marginally with 0.14 percentage point directly after the intervention (p-value .06). The results are limited by the absence of data on antigen tests taken by the traveller at home and missing data from travellers without a valid Norwegian ID. CONCLUSIONS: Our findings suggest that the benefit of mandatory testing of all international travellers to Norway was marginal in the period directly after the emergence of the omicron variant. This result must be understood in the context of free of charge testing at official test centres, a government recommendation on a low threshold to test when experiencing symptoms in addition to limited surveillance of the compliance of the test after arrival requirement.

The correlation between socioeconomic factors and COVID-19 among immigrants in Norway: a register-based study.

AIM: Immigrants in Norway have higher COVID-19 notification and hospitalisation rates than Norwegian-born individuals. The knowledge about the role of socioeconomic factors to explain these differences is limited. We investigate the relationship between socioeconomic indicators at group level and epidemiological data for all notified cases of COVID-19 and related hospitalisations among the 23 largest immigrant groups in Norway. METHODS: We used data on all notified COVID-19 cases in Norway up to 15 November 2020, and associated hospitalisations, from the Norwegian Surveillance System for Communicable Diseases and the emergency preparedness register at the Norwegian Institute of Public Health. We report notified COVID-19 cases and associated hospitalisation rates per 100,000 and their correlation to income, education, unemployment, crowded housing and years of residency at the group level. RESULTS: Crowded housing and low income at a group level were correlated with rates of both notified cases of COVID-19 (Pearson`s correlation coefficient 0.77 and 0.52) and related hospitalisations (0.72, 0.50). In addition, low educational level and unemployment were correlated with a high number of notified cases. CONCLUSIONS: Immigrant groups living in disadvantaged socioeconomic positions are important to target with preventive measures for COVID-19. This must include targeted interventions for low-income families living in overcrowded households.

COVID-19 among immigrants in Norway, notified infections, related hospitalizations and associated mortality: A register-based study.

Aim: Research concerning COVID-19 among immigrants is limited. We present epidemiological data for all notified cases of COVID-19 among the 17 largest immigrant groups in Norway, and related hospitalizations and mortality. Methods: We used data on all notified COVID-19 cases in Norway up to 18 October 2020, and associated hospitalizations and mortality, from the emergency preparedness register (including Norwegian Surveillance System for Communicable Diseases) set up by The Norwegian Institute of Public Health to handle the pandemic. We report numbers and rates per 100,000 people for notified COVID-19 cases, and related hospitalizations and mortality in the 17 largest immigrant groups in Norway, crude and with age adjustment. Results: The notification, hospitalization and mortality rates per 100,000 were 251, 21 and five, respectively, for non-immigrants; 567, 62 and four among immigrants; 408, 27 and two, respectively, for immigrants from Europe, North-America and Oceania; and 773, 106 and six, respectively for immigrants from Africa, Asia and South America. The notification rate was highest among immigrants from Somalia (2057), Pakistan (1868) and Iraq (1616). Differences between immigrants and non-immigrants increased when adjusting for age, especially for mortality. Immigrants had a high number of hospitalizations relative to notified cases compared to non-immigrants. Although the overall COVID-19 notification rate was higher in Oslo than outside of Oslo, the notification rate among immigrants compared to non-immigrants was not higher in Oslo than outside. Conclusions: We observed a higher COVID-19 notification rate in immigrants compared to non-immigrants and much higher hospitalization rate, with major differences between different immigrant groups. Somali-, Pakistani- and Iraqi-born immigrants had especially high rates.