As Covid-19 continues to exact a heavy toll, development of a vaccine appears the most promising means of restoring normalcy to civil life. Perhaps no scientific breakthrough is more eagerly anticipated. But bringing a vaccine to market is only half the challenge; also critical is ensuring a high enough vaccination rate to achieve herd immunity. Concerningly, a recent poll found that only 49% of Americans planned to get vaccinated against SARS-CoV-2.1
One option for increasing vaccine uptake is to require it. Mandatory vaccination has proven effective in ensuring high childhood immunization rates in many high-income countries. However, except for influenza vaccination of health care workers, mandates have not been widely used for adults.
Although a vaccine remains months to years away, developing a policy strategy to ensure uptake takes time. We offer a framework that states can apply now to help ensure uptake of the vaccine when it becomes available — including consideration of when a mandate might become appropriate. Our approach is guided by lessons from U.S. experiences with vaccines for the 1976 “swine flu,” H1N1 influenza, smallpox, and human papillomavirus (HPV).
We believe that six substantive criteria should be met before a state imposes a SARS-CoV-2 vaccine mandate (see box). The first is the existence of evidence that Covid-19 is inadequately controlled in the state by other measures, such as testing, contact tracing, and isolation and quarantine — as indicated by sustained, troubling trends in new cases, hospitalizations, or deaths. Principles of public health law and ethics require that interventions that impinge on autonomy be reasonable and necessary; therefore, Covid-19 must present an ongoing threat. By the time a vaccine is available, more will be known about natural immunity in the population, the consequences of relaxing community mitigation measures, and the feasibility of scaling up test-and-trace strategies. There should be a reasonable indication as to whether further measures are needed.
SIX TRIGGER CRITERIA FOR STATE COVID-19 VACCINATION MANDATES.
- Covid-19 is not adequately contained in the state.
- The Advisory Committee on Immunization Practices has recommended vaccination for the groups for which a mandate is being considered.
- The supply of vaccine is sufficient to cover the population groups for which a mandate is being considered.
- Available evidence about the safety and efficacy of the vaccine has been transparently communicated.
- The state has created infrastructure to provide access to vaccination without financial or logistic barriers, compensation to workers who have adverse effects from a required vaccine, and real-time surveillance of vaccine side effects.
- In a time-limited evaluation, voluntary uptake of the vaccine among high-priority groups has fallen short of the level required to prevent epidemic spread.
The second criterion is that the Advisory Committee on Immunization Practices (ACIP), after reviewing the safety and efficacy evidence, has recommended vaccination for the persons who would be covered by a mandate. Currently available evidence suggests that the elderly, health professionals working in high-risk situations or working with high-risk patients (e.g., nursing home residents and patients with severe respiratory symptoms), and persons with certain underlying medical conditions may be high-priority groups for the ACIP’s consideration, along with other workers with frequent, close, on-the-job contacts and persons living in high-density settings such as prisons and dormitories. When a vaccine nears approval, the ACIP should review the updated evidence and develop recommendations. Only recommended groups should be considered for a vaccination mandate, though health officials can encourage voluntary uptake for others, using means such as public education campaigns and free vaccination.
The fact that a vaccine has received Food and Drug Administration (FDA) approval — whether under an Emergency Use Authorization (EUA) or ordinary review processes — is an insufficient basis on which to conclude that it should be required. FDA approval reflects a determination that clinical trial evidence shows that the benefits of a vaccine outweigh its risks. ACIP recommendations reflect broader considerations, including values and preferences of affected groups, implementation issues, and health economic analyses. Overweighting FDA decisions would be particularly problematic for SARS-CoV-2 vaccines because EUAs may be based on very limited evidence and consciously or unconsciously influenced by the intense pressure to speed countermeasures to market.2