An equity-based assessment of immunization-related responses in urban Alberta during the 2014 measles outbreak: a comparative analysis between Calgary and Edmonton

Objectives This study investigates measles, mumps, and rubella (MMR) immunization rates during the measles outbreak in Calgary and Edmonton of 2014 stratified by four area-level socio-demographic indicators. This study also leverages this epidemiological data to assess the equity aspect of emergency measures instituted regarding immunization in those two cities. Methods A mixed-methods comparative case study analysis methodology was employed to assess the neighbourhood-level immunization statuses before (2013), during (2014), and after (2015) an active measles outbreak in Calgary and Edmonton, Alberta, Canada. The epidemiological one-dose by age-2 MMR coverage data were stratified using four socio-demographic indicators: median household income, %-homeownership, %-Aboriginal population, and %-immigrant population. Document and content analysis was utilized to investigate the outbreak mitigation strategies deployed in each city. Results The measles outbreak of 2013/2014 involved the entirety of Alberta and led to both provincial and city-specific interventions in which Calgary deployed three mass immunization clinics in 2014, where Edmonton did not. The Calgary coverage data showed an increase in coverage inequalities across all indicators and the Edmonton data showed mixed results in terms of equity gains/losses. Calgary’s additive intervention of three mass immunization clinics in 2014 appears to have contributed to both the higher gross immunization rates in Calgary (90.77%) and an inequitable increase in coverage rates as compared with Edmonton (88.96%), in most cases. Conclusion Public health policy-makers must be cognizant that large-scale public health efforts must be optimized for accessibility across all socio-economic levels to ensure public and population health gains are realized equitably.