Projecting the impact of a two-dose COVID-19 vaccination campaign in Ontario, Canada.

BACKGROUND: A number of highly effective COVID-19 vaccines have been developed and approved for mass vaccination. We evaluated the impact of vaccination on COVID-19 outbreak and disease outcomes in Ontario, Canada. METHODS: We used an agent-based transmission model and parameterized it with COVID-19 characteristics, demographics of Ontario, and age-specific clinical outcomes. We implemented a two-dose vaccination program according to tested schedules in clinical trials for Pfizer-BioNTech and Moderna vaccines, prioritizing healthcare workers, individuals with comorbidities, and those aged 65 and older. Daily vaccination rate was parameterized based on vaccine administration data. Using estimates of vaccine efficacy, we projected the impact of vaccination on the overall attack rate, hospitalizations, and deaths. We further investigated the effect of increased daily contacts at different stages during vaccination campaigns on outbreak control. RESULTS: Maintaining non-pharmaceutical interventions (NPIs) with an average of 74% reduction in daily contacts, vaccination with Pfizer-BioNTech and Moderna vaccines was projected to reduce hospitalizations by 27.3% (95% CrI: 22.3% - 32.4%) and 27.0% (95% CrI: 21.9% - 32.6%), respectively, over a one-year time horizon. The largest benefits of vaccination were observed in preventing deaths with reductions of 31.5% (95% CrI: 22.5% - 39.7%) and 31.9% (95% CrI: 22.0% - 41.4%) for Pfizer-BioNTech and Moderna vaccines, respectively, compared to no vaccination. We found that an increase of only 10% in daily contacts at the end of lockdown, when vaccination coverage with only one dose was 6%, would trigger a surge in the outbreak. Early relaxation of population-wide measures could lead to a substantial increase in the number of infections, potentially reaching levels observed during the peak of the second wave in Ontario. CONCLUSIONS: Vaccination can substantially mitigate ongoing COVID-19 outbreaks. Sustaining population-wide NPIs, to allow for a sufficient increase in population-level immunity through vaccination, is essential to prevent future outbreaks.

Cost-effectiveness of a potential vaccine candidate for Haemophilus influenzae serotype 'a'.

The preceding decade has witnessed the emergence of severe community-acquired acute infections caused by Haemophilus influenzae serotype a (Hia), with alarming incidence rates in North America, particularly among indigenous populations. The remarkable success of Hib conjugate vaccine over the past 20 years signify the development of an Hia vaccine candidate as a prevention measure to reduce the incidence of invasive Hia disease. However, quantifications of the long-term epidemiologic and economic impacts of vaccination are needed to inform decision on investment in Hia vaccine development and immunization programs. We sought to evaluate the cost-effectiveness of an Hia vaccine with a similar routine infant immunization schedules currently in practice for Hib in Canada. We developed and parameterized an agent-based simulation model using age-specific incidence rates reported for Nunavut, a Canadian territory with predominantly aboriginal populations. Our results, based on statistical analyses of the incremental cost-effectiveness ratio, show that an Hia conjugate vaccine is highly cost-effective. Sustaining an immunization program with vaccine coverages of 77% for primary series and 93% for booster dose over a 10-year period reduces the incidence of invasive disease by 63.8% on average from 9.97 to 3.61 cases, per 100,000 population. The overall costs of disease management in year 10 are reduced by 53.4% from CDN $1.863 million (95% CI: $1.229-$2.519 M) to CDN $0.868 million (95% CI: $0.627-$1.120 M). The findings suggest an important role for a conjugate vaccine in managing Hia disease as a growing public health threat.

Economic evaluation of vaccines in Canada: A systematic review.

BACKGROUND: Economic evaluations should form part of the basis for public health decision making on new vaccine programs. While Canada's national immunization advisory committee does not systematically include economic evaluations in immunization decision making, there is increasing interest in adopting them. We therefore sought to examine the extent and quality of economic evaluations of vaccines in Canada. OBJECTIVE: We conducted a systematic review of economic evaluations of vaccines in Canada to determine and summarize: comprehensiveness across jurisdictions, studied vaccines, funding sources, study designs, research quality, and changes over time. METHODS: Searches in multiple databases were conducted using the terms "vaccine," "economics" and "Canada." Descriptive data from eligible manuscripts was abstracted and three authors independently evaluated manuscript quality using a 7-point Likert-type scale scoring tool based on criteria from the International Society for Pharmacoeconomics and Outcomes Research (ISPOR). RESULTS: 42/175 articles met the search criteria. Of these, Canada-wide studies were most common (25/42), while provincial studies largely focused on the three populous provinces of Ontario, Quebec and British Columbia. The most common funding source was industry (17/42), followed by government (7/42). 38 studies used mathematical models estimating expected economic benefit while 4 studies examined post-hoc data on established programs. Studies covered 10 diseases, with 28/42 addressing pediatric vaccines. Many studies considered cost-utility (22/42) and the majority of these studies reported favorable economic results (16/22). The mean quality score was 5.9/7 and was consistent over publication date, funding sources, and disease areas. CONCLUSIONS: We observed diverse approaches to evaluate vaccine economics in Canada. Given the increased complexity of economic studies evaluating vaccines and the impact of results on public health practice, Canada needs improved, transparent and consistent processes to review and assess the findings of the economic evaluations of vaccines.

The integration of barcode scanning technology into Canadian public health immunization settings.

BACKGROUND: As part of a series of feasibility studies following the development of Canadian vaccine barcode standards, we compared barcode scanning with manual methods for entering vaccine data into electronic client immunization records in public health settings. METHODS: Two software vendors incorporated barcode scanning functionality into their systems so that Algoma Public Health (APH) in Ontario and four First Nations (FN) communities in Alberta could participate in our study. We compared the recording of client immunization data (vaccine name, lot number, expiry date) using barcode scanning of vaccine vials vs. pre-existing methods of entering vaccine information into the systems. We employed time and motion methodology to evaluate time required for data recording, record audits to assess data quality, and qualitative analysis of immunization staff interviews to gauge user perceptions. RESULTS: We conducted both studies between July and November 2012, with 628 (282 barcoded) vials processed for the APH study, and 749 (408 barcoded) vials for the study in FN communities. Barcode scanning led to significantly fewer immunization record errors than using drop-down menus (APH study: 0% vs. 1.7%; p=0.04) or typing in vaccine data (FN study: 0% vs. 5.6%; p<0.001). There was no significant difference in time to enter vaccine data between scanning and using drop-down menus (27.6s vs. 26.3s; p=0.39), but scanning was significantly faster than typing data into the record (30.3s vs. 41.3s; p<0.001). Seventeen immunization nurses were interviewed; all noted improved record accuracy with scanning, but the majority felt that a more sensitive scanner was needed to reduce the occasional failures to read the 2D barcodes on some vaccines. CONCLUSION: Entering vaccine data into immunization records through barcode scanning led to improved data quality, and was generally well received. Further work is needed to improve barcode readability, particularly for unit-dose vials.

Exploring the feasibility of integrating barcode scanning technology into vaccine inventory recording in seasonal influenza vaccination clinics.

BACKGROUND: In response to the need for improved quality of vaccine inventory and client immunization records, barcodes containing a unique identifier and lot number will be placed on all vaccine vials in Canada. We conducted feasibility studies to examine integration of barcode scanning into inventory recording workflow for mass immunization clinics. METHODS: During the 2010-2011 seasonal influenza vaccination campaign, Ontario public health units (PHUs) using an electronic immunization system were randomized to record clinic inventory data (including vaccine lot number and expiry date) through: (i) barcode scanning of vials; or (ii) drop-down menus. A third group of PHUs recording vaccine inventory on paper served as an observation arm. We visited a sample of clinics within each PHU to assess barcode readability, method efficiency and data quality. Clinic staff completed a survey examining method perceptions. RESULTS: We observed 20 clinics using barcode scanning to record inventory data (eight PHUs), 20 using drop-down menus (eight PHUs), and 21 using paper forms (five PHUs). Mean time spent recording data per vial was 4.3s using barcode scanners with 1.3 scan attempts per vial, 0.5s using drop-down menus, and 1.7s using paper. Few errors were observed. Sixty-four perception surveys were completed by inventory staff; barcode scanning users indicated fairly strong overall satisfaction with the method (74%), and the majority agreed that barcode scanning improved client safety (84%) and inventory record accuracy (77%). However, 38% of barcode scanning users felt that individually scanning vials took longer than the other approaches and 26% indicated that this increased time would discourage them from adopting the method. CONCLUSIONS: Our study demonstrated good readability of barcodes but scanning individual vials for high-volume clinics was time-consuming; modifying the process will improve feasibility to facilitate adoption in Canada, while serving as an example for other countries considering this technology.