In a recent article published in JAMA Network Open, researchers did a retrospective population-based cohort study in Ontario, Canada, to determine coronavirus disease 2019 (COVID-19) vaccination rates for refugee, nonimmigrant, and immigrant children and adolescents (five to 11 and 12 to 17 years, respectively).
Study: COVID-19 Vaccine Uptake in Immigrant, Refugee, and Nonimmigrant Children and Adolescents in Ontario, Canada. Image Credit: DrazenZigic/Shutterstock.com
They accessed data through the International Credential Evaluation Service (ICES), a nonprofit research institute that collates and provides healthcare data for health system evaluation.
It helped the researchers analyze data for children and adolescents in Ontario collected between May 9 and August 2, 2022. All these minors had registered in the Universal Ontario Health Insurance Program for at least one year starting January 1, 2021.
Studies have found that racialized populations, e.g., Arab, Black, and Latin Americans who migrate to North America, including the United States of America (USA) and Canada, have a higher hesitancy to vaccinate their children for COVID-19 because of their cultural beliefs, religious beliefs and poor experiences with the health system despite adequate supply and accessibility to vaccines through public health care systems.
Since COVID-19 has adversely affected pediatric populations worldwide, US and Canadian public health guidance strongly recommends COVID-19 vaccinations for children and adolescents.
Health Canada authorized a $1.5 billion COVID-19 vaccine campaign in December 2020 with a strong focus on vaccine's equitable distribution, first for healthcare workers and older individuals, and for adolescents by May 2021 and children by November 2021.
The adolescent vaccination campaign focused on highly diverse populations, including immigrants and essential workers, because in Ontario, Canada's largest province, 30% of people identify as immigrants, of whom ~70% are racial minorities.
Within three months of immigrant and refugee arrival in Canada, they are insured through provincial insurance or a temporary federal program.
Those who lack proper documents are also offered free primary care through community healthcare centers, which makes all Ontario residents eligible for free COVID-19 vaccinations.
About the study
In the present study, researchers made two assumptions for evaluating the success of COVID-19 vaccine campaigns run in Ontario, Canada, for minors of immigrants and refugees.
First, they hypothesized that COVID-19 vaccine coverage would be higher and homogenous in adolescents than in children.
Second, they assumed that the COVID-19 vaccine uptake rate between immigrant and refugee groups would vary with immigration category and country/region of origin. They stratified the study cohort based on the COVID-19 vaccine campaigns run in 2021 in Ontario, covering adolescents by May 2021 and children by November 2021.
The two outcome exposures of the current study were immigrant\refugee status, region of origin, and generation (first/second) of immigrant minors, including their immigration category and time of immigration (recency).
Likewise, the two study outcomes were crude COVID-19 vaccination rates, defined as one or more than one vaccine dose for children and two or more than two vaccine doses for adolescents.
The team used a logistic regression model to model the association of the immigrant category with vaccination across the study cohort, including all covariates, age, gender, other pediatric diseases, receipt of influenza vaccine in 2019/2020, primary health care model, and COVID-19 history.
They also performed a generation-stratified analysis of first- and second-generation immigrants and refugees, including key mediators, like the material deprivation quintile.
Finally, the team used time-to-event models to compute adjusted hazard ratios (aHRs) associated with the first vaccination dose with 95% confidence intervals (CIs), adjusted for sociodemographic, clinical, and health system factors.
The study cohort had ~2.2 million minors, of which 1,098,749 and 1,142,429 were children and adolescents, respectively. Both groups had 51.3% males, and their median ages were 7.06 and 14 years, respectively.
In the cohort comprising children, 4.8% and 23.4% were first- and second-generation immigrants or refugees, whereas in adolescents, their numbers were 9.2% and 19.4%, respectively.
The regions of origin of immigrant and refugee minors were South Asia, followed by the Middle East. As expected, immigrants, especially refugees, lived in neighborhoods with the highest material deprivation, a construct based on the census-based Ontario Marginalization Index.
In Ontario, Canada, COVID-19 vaccination coverage was 53.1% and 79.2% in immigrant children and adolescents, respectively, compared with nonimmigrants.
The authors noted marked variations within immigrant groups based on region of origin in first- and second-generation immigrants and refugees. This heterogeneity persisted even after adjusting for immigration category and sociodemographic factors.
In models stratified by generation, the authors noted an association between the region of origin and vaccine uptake, compared with the overall rate, with the lowest odds observed in immigrants and refugees from East Europe and Central Africa (children: aOR, 0.40 vs. 0.24; adolescents: aOR, 0.41 vs. 0.51; 95% CI).
The highest odds were in minors from Southeast Asia (children and adolescents: aORs=2.68 vs. 4.42; 95% CI). Vaccination aORs among immigrant and refugee minors from regions with the lowest vaccine coverage did not vary with generations.
The current population-based study demonstrated that COVID-19 vaccination coverage was lower among immigrant minors, and the observed heterogeneity by region of origin was substantial and persisted across generations.
Thus, precision public health approaches should target immigrants, especially refugee minors, in ongoing vaccine campaigns.