Transition to endemic: acceptance of additional COVID-19 vaccine doses among Canadian adults in a national cross-sectional survey

Abstract

Background Additional doses of COVID-19 vaccine have been proposed as solutions to waning immunity and decreased effectiveness of primary doses against infection with new SARS-CoV-2 variants. However, the effectiveness of additional vaccine doses relies on widespread population acceptance. We aimed to assess the acceptance of additional COVID-19 vaccine doses (third and annual doses) among Canadian adults and determine associated factors. Methods We conducted a national, cross-sectional online survey among Canadian adults from October 14 to November 12, 2021. Weighted multinomial logistic regression analyses were used to identify sociodemographic and health-related factors associated with third and annual dose acceptance and indecision, compared to refusal. We also assessed influences on vaccine decision-making, and preferences for future vaccine delivery. Results Of 6010 respondents, 70% reported they would accept a third dose, while 15.2% were undecided. For annual doses, 64% reported acceptance, while 17.5% were undecided. Factors associated with third dose acceptance and indecision were similar to those associated with annual dose acceptance and indecision. Previous COVID-19 vaccine receipt, no history of COVID-19 disease, intention to receive an influenza vaccine, and increasing age were strongly associated with both acceptance and indecision. Chronic illness was associated with higher odds of acceptance, while self-reported disability was associated with higher odds of being undecided. Higher education attainment and higher income were associated with higher odds of accepting additional doses. Minority first language was associated with being undecided about additional doses, while visible minority identity was associated with being undecided about a third dose and refusing an annual dose. All respondents reported government recommendations were an important influence on their decision-making and identified pharmacy-based delivery and drop-in appointments as desirable. Co-administration of COVID-19 and influenza vaccines was viewed positively by 75.5% of the dose 3 acceptance group, 12.3% of the undecided group, and 8.4% of the refusal group. Conclusions To increase acceptance, targeted interventions among visible minority and minority language populations, and those with a disability, are required. Offering vaccination at pharmacies and through drop-in appointments are important to facilitate uptake, while offering COVID-19/influenza vaccine co-administration may have little benefit among those undecided about additional doses.

Exploring Factors Associated with Chinese-Americans’ Willingness to Receive an Additional Hypothetical Annual Dose of the COVID-19 Vaccine

“…Our findings are similar with a cross-sectional survey study conducted in Europe, which indicated that 82.4% of participants from a German-speaking region were willing to receive annual vaccinations. However, the percentage from our study is higher than that of a survey study to examine Canadian adults’ willingness to accept annual vaccines, which indicated that 64.7% of the respondents reported the acceptance of an annual COVID-19 vaccine dose [ 13 ]. The high acceptance rate among Chinese-American participants in our study may suggest that the idea of making COVID-19 vaccination an annual routine is feasible and acceptable.…”

“…Future winter surges of COVID-19 have been predicted by five years of epidemiological models which suggest that COVID-19 is likely becoming another endemic respiratory virus that may require annual or intermittent booster immunization for the management and control of the pandemic due to the global mutations and the success of the authorized vaccine [ 11 , 12 ]. While the scientific evidence for annual vaccination is promising, this strategy needs population acceptance and public health vaccination promotion efforts [ 13 ]. It is critical to understand an individual’s intentions concerning potential annual COVID-19 vaccination and the factors associated with their vaccination decisions.…”

“…Intentions toward hypothetical annual COVID-19 vaccination is largely unknown. Among the limited literature, racial/ethnic minorities were found to be more likely to have a lower vaccination willingness than White respondents when it comes to COVID-19 annual vaccine in both the U.S. and Canada [ 9 , 13 ].…”

A Scoping Review of Three Dimensions for Long-Term COVID-19 Vaccination Models: Hybrid Immunity, Individual Drivers of Vaccinal Choice, and Human Errors

“…This is now a reality, and most Americans understand that COVID-19 is here to stay [ 1 ]. As mutations and natural selection continue to occur, new variants emerge and vaccines need to be continuously redeveloped [ 14 ] and adopted by the population [ 17 , 18 , 19 , 20 , 21 , 22 ]. In the U.S., the federal government has purchased 66 million doses of bivalent boosters that target BA.4 and BA.5 Omicron subvariants [ 108 ].…”

“…On the other hand, we likely need annual vaccine composition updates [ 18 ]. Surveys in Jordan show that less than 1 in 5 persons would take an annual booster [ 19 ], while about 2 in 3 Canadians [ 20 ] and more than 4 in 5 German-speaking adults would be willing [ 21 ]. Results in the U.S. are mixed, as surveys were conducted across sub-populations with different profiles [ 22 ].…”