Background: The Norwegian Institute of Public Health's statistics on immunisation against SARS-CoV-2 show that vaccination coverage for foreign-born persons living in Norway is lower than for persons born in Norway. As of January 2022, the difference was 18 percentage points (76 % versus 94 %). This difference is likely to be due to several factors, one of which may be that many of those who were immunised abroad have not had this registered in the Norwegian Immunisation Registry.
Material and method: In November 2021, the Norwegian Institute of Public Health conducted a public health survey in the county of Viken. Respondents were asked if they had been vaccinated against the coronavirus, if they were vaccinated in Norway or abroad, and if immunisation abroad had been reported to the Norwegian health service. They were also asked to specify their country of birth. The sample was drawn from the National Population Register. The survey was conducted online and the response rate was 41 % (n = 108 738).
Results: A total of 105 010 (97 %) of the respondents had had at least one dose of the coronavirus vaccine. Of these, 724 (<1 %) had only been vaccinated abroad. This applied to 392 (3 %) of the 13 286 foreign-born persons, 203 (52 %) of whom had reported their immunisation to the Norwegian health service.
Interpretation: In this dataset, unregistered immunisation abroad explains only a small proportion of the difference in vaccination coverage between Norwegian-born and foreign-born persons.