SAN FRANCISCO (KPIX) – San Francisco will become the first city in California to require new employees be vaccinated. The rule takes effect on Wednesday, and while not everyone agrees with the mandate, this isn’t the first time American workers have been told to get a vaccine.

It was an outbreak of smallpox in Cambridge, Massachusetts in 1902 that resulted in a vaccine order in that city. Three years later, in Jacobson v. Massachusetts, the Supreme Court upheld that mandate in a decision that is cited as precedent to this day. It’s used to uphold vaccination requirements for school, even the mask mandates that have been challenged during this pandemic.

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When it comes to compelling vaccinations, the state has options.

“We’re seeing what’s happening with the Delta variant,” says Cal State East Bay Department of Public Health Chair Arnab Mukherjea. “We’re seeing low voluntary uptake on the vaccination. So I think it was time to do it, if not earlier.”

When classes resume on Cal State campuses, COVID vaccinations will be mandatory. It’s a policy university professors had been openly calling for.

“With about half the country not vaccinated and what’s happening with the Delta variant I think this is, sadly, what we’re going to have to do — use the vehicle of public policy to compel safety and protection for the public,” Mukherjea explains.

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“I think, at this point, the evidence is crystal clear that the things that we have done so far to motivate vaccination or not enough to get us to a place that gets us out of this pandemic,” says Dr. Robert M. Wachter Chairof the UCSF Department of Medicine.

Wachter says without Delta, the Bay Area’s current vaccination rate would probably be enough to contain the pandemic. That is why public health messaging has largely been a persuasion campaign, until now.

“Give people the opportunity to understand the detriment of not being vaccinated, the benefits of being vaccinated,” says Nia Lindsey of Walnut Creek, a vaccine supporter who does not necessarily support mandates.

But health officials say the Delta variant has changed the math, requiring a higher vaccination rate. Wachter says the best way to drive that is to make the shot a virtual necessity for just about anyone who wants to do much of anything.

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“I’m not sure I would compel people who are planning on staying in their house and are comfortable doing that,” Wachter explains. “The same way I wouldn’t compel someone to wear a mask at home. But when you say you are either going to go into a public place and we’re going to limit whether you can if you’re not vaccinated, or you can’t work as a teacher, or you can’t work as a nurse or a doctor, or you can’t get on an airplane or going to restaurant, I think there’s a public interest in all of those things and it’s clear, the law and the ethics seem clear, that you can do that.”