A growing list of huge companies, from Google and Walmart to Tyson Foods and United Airlines, have announced they’ll require vaccine shots for employees, customers or both. Restaurants and other small businesses are, too. But making a mandate is one thing; figuring out the enforcement, the caveats and the impact of it is another.

Take Walmart. It’s the nation’s largest private employer, but its vaccine mandate only applies to management and corporate workers, not the folks staffing its stores or distribution centers.

“I think it’s really important for people to think through, like, who are these mandates being placed on? And what’s the feasibility of getting people to comply with this?” said MIT Technology Review reporter Mia Sato.

On today’s show, Sato walks us through how these mandates happened, who gets left out from them and whether corporate America can actually save “hot vax summer” from the surge in delta variant cases.

Marketplace’s Kimberly Adams and Andy Uhler are hosting the show today, and later on we’ll talk about news from both their home states (Missouri and Texas), and hear from a vaccinated listener who contracted a rare breakthrough case of COVID-19. Oh, and we’ll talk about the infrastructure bill passing the Senate, which happened right as we started recording

When you’re done listening, tell your Echo device to “make me smart” for our daily explainers. This week, we’re explaining the Gini coefficient, the divided supply chain and business suits. Remember those? You can hear all our explainers here. And don’t forget to subscribe to our newsletter! You can find the latest issue here.

Here’s everything we talked about today:

• Sato’s latest for Technology Review’s Pandemic Technology Project: “The best vaccine incentive might be paid time off“

• “Covid vaccine mandates sweep across corporate America as delta variant spurs action” from CNBC

• “Covid-19 Vaccine Mandates Split Corporate America” from The Wall Street Journal

• “Bollinger’s Mill and Burfordville Covered Bridge Featured on Missouri Statehood Stamp” from USPS, plus some background on that bridge

• “Out-of-state healthcare workers coming to Texas as state hits record low ICU beds, Gov. Abbott announces” from KXAN in Austin

• “Senate Passes Bipartisan Infrastructure Bill” from The Wall Street Journal

Read the transcript here.

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