Potential influence of seasonal influenza vaccination requirement versus traditional vaccine promotion strategies on unvaccinated healthcare personnel

Did the health care vaccine mandate work? An evaluation of the impact of the COVID-19 vaccine mandate on vaccine uptake and infection risk in a large cohort of Canadian health care workers

BACKGROUND

We aimed to evaluate the impact of health care vaccine mandates on vaccine uptake and infection risk in a cohort of Canadian health care workers (HCWs).

METHODS

We conduct interrupted time series analysis through a regression discontinuity in time approach to estimate the immediate and delayed impact of the mandate. Multilevel mixed effect modeling fitted with restricted maximum likelihood was used to estimate impact on infection risk.

RESULTS

The immediate and sustained effects of the mandate was a 0.19% (P < .05) and a 0.012% (P < .05) increase in the daily proportion of unvaccinated HCWs getting their first dose, respectively. An additional 623 (95% confidence interval: 613-667) HCWs received first doses compared to the predicted uptake absent the mandate. Adjusted test positivity declined by 0.053% (95% confidence interval: 0.035%, 0.069) for every additional day the mandate was in effect.

DISCUSSION

Our results indicate that the mandate was associated with significant increases in vaccine uptake and infection risk reduction in the cohort.

CONCLUSIONS

Given the benefit that vaccination could bring to HCWs, understanding strategies to enhance uptake is crucial for bolstering health system resilience, but steps must be taken to avert approaches that sacrifice trust, foster animosity, or exacerbate staffing constraints for short-term results.

Rather than inducing psychological reactance, requiring vaccination strengthens intentions to vaccinate in US populations

In a survey and three experiments (one preregistered with a nationally representative sample), we examined if vaccination requirements are likely to backfire, as commonly feared. We investigated if relative to encouraging free choice in vaccination, requiring a vaccine weakens or strengthens vaccination intentions, both in general and among individuals with a predisposition to experience psychological reactance. In the four studies, compared to free choice, requirements strengthened vaccination intentions across racial and ethnic groups, across studies, and across levels of trait psychological reactance. The results consistently suggest that fears of a backlash against vaccine mandates may be unfounded and that requirements will promote COVID-19 vaccine uptake in the United States.

Healthcare Workers' (HCWs) attitudes towards mandatory influenza vaccination: A systematic review and meta-analysis

Influenza is a disease responsible for thousands of deaths every year. Although healthcare workers (HCWs) represent a way of contagion for patients, vaccination coverage among them is low. Mandatory vaccination has been proposed, but controversies remain. This systematic review and meta-analysis aimed to assess the acceptance of mandatory vaccination by HCWs, and to investigate associated characteristics. MEDLINE, Scopus, Embase, PsycInfo, CINAHL and Web of Science were used to search for studies assessing the topic. PRISMA statements were followed. Of the 13,457 univocal records found, 52 studies were included in the systematic review and 40 in the meta-analysis. The pooled proportion of HCWs accepting the policy was of 61% (95% CI: 53%- 68%) but with great heterogeneity between continents (from 54% in Europe to 69% in Asia) and in different professionals (from 40% in nurses to 80% in students). Vaccinated HCWs agreed more frequently with mandatory vaccination than non-vaccinated ones. More studies that consider mandatory vaccination acceptance as the main outcome are needed, but the results of this study confirm that in some settings the majority of HCWs favour mandatory vaccination. This, combined with effects that a flu epidemic could have if overlapped to pandemics with similar symptoms, requires renewed considerations on mandatory vaccination.

Maximizing influenza vaccination uptake among healthcare personnel in Israel: lessons learned from mandatory vaccination policy in the United States

Background

Maximizing vaccination uptake is crucial in generating herd immunity and preventing infection incidence (Quach et al., Am J Infect Control 11:1017–23, 2013). Vaccination of healthcare personnel (HCP) against influenza is vital to influenza infection control in healthcare settings, given the consistent exposure of HCP to high-risk patients like: those with compromised immune systems, children, and the elderly (Johnson & Talbot, Curr Opin Infect Dis 24: 363–369, 2011). Influenza vaccination uptake among HCP remains suboptimal: in 2017–18, 47.6% of HCP who worked in settings where influenza vaccination was not mandatory were vaccinated against influenza in United States (Black et al., Morb Mortal Wkly Rep 67: 1050, 2018). Mandatory vaccination policies result in HCP influenza vaccination uptake rates substantially higher than opt-in influenza vaccination campaigns (94.8% vs. 47.6%) (Black et al., Morb Mortal Wkly Rep 67: 1050, 2018).

Goals

The Israel Journal of Health Policy Research has published articles focused on the issues of influenza vaccination (Yamin et al., Isr J Health Policy Res 3: 13, 2014), improving influenza vaccination coverage of HCP (Weber et al., Isr J Health Policy Res 5: 1–5, 2016), influenza vaccination motivators among HCP (Nutman and Yoeli, Isr J Health Policy Res 5: 52, 2016), legal imposition of vaccination (Kamin-Friedman, Isr J Health Policy Res 6:58, 2017), and mandatory vaccination (Gostin, Cell Biosci 8: 1-4, 2018). Each article explores factors influencing disease prevention from different angles within an Israeli context. This article attempts to fuse these topics by investigating how to apply aspects of American mandatory influenza vaccination policy targeted at HCP in an Israeli context.

Methods

Critical document analysis was conducted on relevant literature and policy discussing influenza prevention interventions among HCP within the United States. Mandatory vaccination policies were highlighted. A discussion of the professional responsibility of HCP to vaccinate against influenza serves as background. Case studies of hospitals in the United States that implemented mandatory vaccination policies for their employees are analyzed. The article concludes with analysis exploring how qualities of mandatory influenza vaccination policy of HCP could take shape in Israel, giving contextual limitations, urging Israeli health policy makers to reflect on lessons learned from the American case study.

Main findings and conclusion

Mandatory HCP influenza vaccination policies in comparison to non-mandatory interventions are most effective in obtaining maximum influenza vaccination uptake among HCP (Black et al., Morb Mortal Wkly Rep 67: 1050, 2018). Many HCP cite individual objections to influenza vaccination rooted in personal doubts and ethical concerns. The ethical responsibility of HCP to their patients and work environments to prevent and lower influenza infection incidence arguably overrules such individual objections. Mandatory HCP influenza vaccination policies are an effective method of maximizing HCP influenza vaccine uptake and minimizing the spread of the influenza virus within healthcare settings. Still, cultural, social and political sensitivity must be taken into consideration when implementing both full-on mandatory HCP influenza vaccination policies and/or aspects of mandatory policies, especially within an Israeli context.

Reduced serologic sensitivity to influenza A virus illness among inactivated influenza vaccinees

We compared ≥4-fold increases in antibody titers by hemagglutination inhibition assay to RT-PCR results among 42 adults with PCR-confirmed influenza A virus illnesses. Serologic sensitivity was higher among unvaccinated (69%, 95% confidence interval [CI]=48-90%) than vaccinated healthcare personnel (38%, 95% CI=29-46%) in a 2010-11 prospective cohort.

Persistence and avidity maturation of antibodies to A(H1N1)pdm09 in healthcare workers following repeated annual vaccinations

Healthcare workers are at increased risk of influenza infection through direct patient care, particularly during the early stages of a pandemic. Although influenza vaccination is widely recommended in Healthcare workers, data on long-term immunogenicity of vaccination in healthcare workers are lacking. The present study was designed to assess the persistence of the humoral response after pandemic vaccination as well as the impact of repeated annual vaccination in healthcare workers (n=24). Pandemic influenza vaccination resulted in a significant increase in haemagglutination inhibition (HI) antibody titers with 93-100% of subjects achieving protective titers 21-days post each of the three annual vaccinations. Seroprotective antibodies measured by HI, microneutralization and single radial hemolysis assays were present in 77-94% of healthcare workers 6 months post-vaccination. Repeated vaccination resulted in an increased duration of seroprotective antibodies with seroprotective titers increasing from 35-62% 12 months after 2009 pandemic vaccination to 50-75% 12 months after 2010 vaccination. Furthermore, repeated annual vaccination augmented the avidity of influenza-specific IgG antibodies. In conclusion, we have shown that A(H1N1)pdm09 vaccination induces high seroprotective titers that persist for at least 6 months. We demonstrate that repeated vaccination is beneficial to healthcare workers and results in further avidity maturation of vaccine-induced antibodies.

Examining the views of key stakeholders regarding the provision of occupational influenza vaccination for healthcare workers in Australia

Annual vaccination of hospital healthcare workers (HCWs) may be an effective measure to reduce the transmission of healthcare associated influenza. However, vaccine coverage rates among HCWs in most public Australian hospitals are below satisfactory for a number of reasons. This study aimed to examine the opinions of key health stakeholders on current issues regarding HCW influenza vaccination. A qualitative study involving semi-structured interviews was undertaken with key Australian health stakeholders representing different organizations and sectors involved in influenza vaccination and policy. Amongst the participants, there was overwhelming support for HCW influenza vaccination. They viewed vaccination as one of the most important preventive measures for healthcare associated influenza and generally agreed that vaccination of HCWs reduces the overall risk of transmission to patients. However, there were contradictory attitudes regarding the evidence available for justifying the impact of vaccinating HCWs against influenza. Amongst the stakeholders interviewed, there was support for continuing to promote influenza vaccination for HCWs via the conventional framework. Participants recommended that hospitals continue to use conventional, voluntary strategies to increase vaccine coverage such as education and mobile carts. Given that the World Health Organization has included HCWs as a target group for influenza vaccination, Australian hospitals may need to start considering the use of mandatory policies in the near future.