The incidence of SARS-CoV-2 infection was the highest among persons of African (excl. North Africa) origin and the Middle East/North African origin. Complete COVID-19 vaccine uptake was highest among persons originating from Southeast Asia and Asia (excl. Southeast Asia)/Latin America. The complete vaccine uptake was lower for persons originating from Africa (excl. North Africa), Russia/former Soviet Union, and Estonia in comparison with persons originating from rest of Europe /North America/Oceania both before and after adjusting for sociodemographic and other variables. older age, age at migration > 18 years, length of stay in Finland 12 or more years were associated with higher complete vaccine uptake whereas, economically inactive groups, experiences of discrimination and psychological distress were associated with lower complete vaccine uptake in our study.
Migrant origin persons in Norway have been recently reported to have a lower COVID-19 vaccine uptake than those who were Norwegian-born with Norwegian-born parents [8]. The Norwegian study also observed lower vaccine uptake among those originating from the East-European countries (Latvia, Bulgaria, Romania, Poland and Lithuania) and higher vaccine uptake among persons originating from the Southeast Asian countries (Vietnam, the Philippines, Thailand) in comparison to persons of Norwegian origin. In our study, vaccine uptake for Estonia and Russia/former Soviet Union group was lower compared with other regional groups. Additionally, our findings on high vaccine uptake among persons originating from South Asian countries are also in consistency with findings from Norway. One key difference between our study and the Norwegian study is that, in addition to at least one COVID-19 vaccine, we also considered previous SARS-CoV-2 infection in our definition of complete vaccine uptake, whereas the Norwegian study only included individuals with at least one dose of COVID-19 vaccine. A previous SARS-CoV-2 infection can be considered equivalent to one dose of vaccine in protecting from future COVID-19 infection [20–21]. Considering the observed high incidence of previous SARS-CoV-2 infections, this information had a significant impact on the calculated outcome variable of vaccine uptake.
Overall, 61% of the persons of migrant origin had complete vaccine uptake in Finland by November 16, 2021. Persons originating from Estonia had the lowest proportion of those with complete vaccine uptake in our study. One explanation for this could be that those of Estonian origin might travel to Estonia to get the vaccination. In such cases, data on receipt of these injections would not appear in the National Vaccine Register of Finland. In addition to persons of Estonian origin, persons originating from Russia/ former Soviet Union and Africa (excl. North Africa) were also less likely than persons originating from rest of Europe/North America/ Oceania to have complete vaccine uptake. Based on available information from Estonia and Russia, 62% of the population in Estonia and 45% of the population in Russia got at least one or more COVID-19 vaccines by November 2021 [22]. Hence, it is also possible that lower vaccine uptake among persons of Russian or former Soviet Union and Estonian origin who took part in the current study, may reflect lower vaccine uptake in their countries of origin.
Vaccine hesitancy is one of the factors contributing to COVID-19 vaccine uptake. The WHO Strategic Advisory Group of Experts (SAGE) working group on vaccine hesitancy defines vaccine hesitancy as a delay in acceptance or refusal of vaccination when vaccination services are available [23]. A recent systematic review explored access to and acceptance of COVID-19 vaccines in high-income countries by ethnicity and migrant origin [24]. Most of the studies included in the review were conducted in the US and the UK. The study reported that there was consistent evidence of elevated levels of COVID-19 vaccine hesitancy among Black/Afro-Caribbean ethnic groups in the US and the UK. Asians in the US had the highest intention rate to get COVID-19 vaccine (81%) compared to other ethnic groups (40–68%) [24]. Lack of confidence, mainly due to mistrust of government and health systems coupled with poor communication were the main barriers to vaccination uptake among persons of Black ethnicity and migrant origin populations [24]. Some other factors associated with lower vaccination intentions in the high-income countries were identified, including having no health insurance, unemployment, lower socio-economic position, female gender, younger age, medical mistrust, less confidence in vaccine efficacy, and less trust in pharmaceutical companies producing the vaccines [25–31].
Persons in the older age groups were more likely to have complete vaccine uptake than those in the younger age groups. Lower socioeconomic position is one of the reasons among persons of migrant origin for poorer outcomes including lower COVID-19 vaccine uptake [4]. We observed similar results in our study. Compared to those who were working full-time or part-time, all others (students, unemployed and others) had lower complete vaccine uptake. Experiences of discrimination and psychological distress were factors affecting lower complete vaccination uptake in this study. We did not find any studies on the association of experience of discrimination and vaccine uptake among migrant origin persons. However, there is a body of evidence that showed that experiences of discrimination and psychological stress were adversely related to mental health, physical health, including preclinical indicators of disease, health behaviors, utilization of health care, and adherence to medical regimens [32–34]. Experiences of discrimination during the Covid-19 pandemic were particularly common among persons of East and Southeast Asian, Middle East, and African origin in Finland [2].
Female sex was often found to be associated with lower COVID-19 vaccination uptake in previous studies [7, 29, 35]. However, in our study we observed that males were associated with lower vaccine uptake in the total sample but not in the MigCOVID sub-sample. Persons living longer i.e. length of stay of 12 years or more were more likely to have complete vaccine uptake compared to those living for 3 to < 7 years in the total sample but not in the MigCOVID sub-sample. Generally, the longer the person stays in the country, s/he has a greater chance of integrating in the society and the more likely s/he is to have a good knowledge about the health system and services compared to those who recently moved from another country. Intermediate or beginner Finnish/Swedish language skills were also associated with lower vaccine uptake, highlighting the need for accessible multilingual communications. Those not able to follow the official information on vaccines disseminated by health authorities may be more susceptible to seeking information from other, less reliable sources, and therefore may be at a great risk for exposure to misinformation or disinformation.
Strengths and limitations
This is the first study to examine sociodemographic and health-related factors associated with complete COVID-19 vaccine uptake among persons of migrant origin in Finland. A significant strength of the current study is availability of register data on previous laboratory-confirmed SAR-COV-2 infection in addition to the number of the COVID-19 vaccine doses, which were used to define our outcome variable, i.e., complete vaccine uptake. Most of the previous studies relied only on the number of COVID-19 vaccine doses to define vaccine uptake. Vaccination status was extracted from the infectious disease register, and Finnish registers, in general, have good validity. A further strength is population-based random sampling design and availability of sociodemographic register data that could be linked with other register data. Additionally, a significant strength is the availability of self-reported health-related data on for the MigCOVID sub-sample, allowing to take into account such important migration-related variables such as language proficiency, experiences of discrimination, self-rated health, and psychological distress, which would not have been available from registers alone.
Some limitations also need to be addressed. Data on the general population was not available for the current study, which would have been helpful in contextualizing the findings. Additionally, information on COVID-19 vaccines administered in other countries was also not available in Finnish registers. Some of the persons who have migrated to Finland from the neighbouring countries, for example from Russia or the former Soviet Union, Estonia, and the rest of Europe may have taken a vaccine in their country of origin. Some selection bias was observed when comparing the total study sample and the MigCOVID Survey sub-sample (for example, MigCOVID survey samples had higher complete vaccine uptake than those of total study sample, possibly due to the smaller sample size, see supplementary Table 2). Such selectivity is commonly observed in population-based surveys, and the selectivity was made transparent in the current study, providing more in-depth insights on the findings than if these would have been presented for the sub-sample only.