A non-trivial percentage of healthcare workers were infected in 2020 and recovered with natural immunity to Covid. Some of those feel strongly enough about vaccine mandates that they are prepared to move jurisdictions or retire, which would exacerbate existing staffing shortages in some hospitals. If we don't want more hospital shortages, we should reconsider unnecessary vaccine mandates for those with hard-earned natural immunity, which includes nasal/mucosal immunity, unlike intramuscular vaccines that were developed for symptom reduction, https://www.statnews.com/2021/08/10/covid-intranasal-vaccine...
> Vaccines that are injected into the arm have done a spectacular job at preventing severe disease and death. But they do not generate the kind of protection in the nasal passages that would be needed to block all infection. That’s called “sterilizing immunity.” The fact that the vaccines don’t block all infections and don’t prevent vaccinated people from transmitting isn’t a big surprise, said Kathryn Edwards, a vaccine expert at Vanderbilt School of Medicine.
The UK's SAGE also commented on nasal (inhaler) vaccine development and the consequences of non-sterilizing intramuscular vaccines for variants, https://www.gov.uk/government/publications/long-term-evoluti...
> Whilst we feel that current vaccines are excellent for reducing the risk of hospital admission and disease, we propose that research be focused on vaccines that also induce high and durable levels of mucosal immunity in order to reduce infection of and transmission from vaccinated individuals. This could also reduce the possibility of variant selection in vaccinated individuals.