Non-pharmaceutical interventions and vaccination during COVID-19 in Canada: Implications for COVID and non-COVID outcomes

Abstract

BackgroundAs a federal country where health prerogatives are primarily at the subnational level (provinces), Canada has implemented non-pharmaceutical interventions (NPIs) of differing stringency and attained varied COVID-19 vaccination coverage across the different vaccination campaigns. NPIs and vaccination may have thus interacted in different ways. MethodsA mixed-methods design combining a regression analysis and a comparative case study. The regression analysis focuses on COVID-19 outcomes such as COVID-19 cases, deaths, hospitalizations, and admissions in intensive care units. The case study centers on three provinces and explores outcomes beyond COVID-19, such as spillover on the healthcare system and the economy. ResultsWhile more stringent NPIs are associated with lower COVID outcomes, their interaction with vaccination coverage depends on the vaccination campaign. Increasing the vaccination coverage with more stringent NPIs was not associated with a decrease in COVID cases growth rate during the primary campaign (two-doses), however it was associated with a decrease in COVID hospitalizations during the booster campaign. For non-COVID outcomes, having less stringent restrictions and lower initial vaccination coverage did not help prevent longer wait times for healthcare nor higher initial unemployment. ConclusionThe differing interaction between NPIs and vaccination coverage suggests that the interaction was more effective when the vaccine uptake was primarily from high-risk populations. Confirming this finding would require further detailed microdata analysis.