CHICAGO (CBS) — A vaccine mixup in Baltimore will have a local impact, after roughly 15 million Johnson & Johnson doses had to be tossed.

As CBS 2’s Marissa Parra reported Thursday, this has been an unexpected hurdle in the race to get people vaccinated before another surge.

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“Your heart just sinks,” said CBS News Medical Contributor Dr. David Agus. “Every vaccine is literally a life with the potential to be saved.”

And in the world of vaccines, Dr. David Agus points out that Johnson and Johnson is the equalizer of the liquid gold. It’s refrigerated, it’s easy to handle, and it’s a one-stop shot.

“This is a vaccine that can go to people rather than people coming to the vaccine,” Agus said.

Health departments like Chicago’s have big plans for the Johnson & Johnson vaccine – such as using it for mass-vaccination sites, bringing it to congregate settings like O’Hare International Airport and factories, and using the vaccine to expand programs that bring the vaccines to the homes of people who can’t leave theirs.

Chicago’s top COVID expert, Department of Public Health Commissioner Dr. Allison Arwady, said as we receive less Pfizer and Moderna vaccines, the city is banking on Johnson & Johnson this week – receiving almost 40,000 doses.

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“We’d d heard there would be more growth there,” Arwady said. “I am concerned that in the next couple weeks we may get very little.”

Call it the trickle-down effect – county health departments said they are waiting to find out how much – or how little – of the vaccine they’ll get.

Parra: “Do you think there’s more of a concern over this for health departments in places like Chicago as opposed to more rural places?”

Agus: “Big cities have significant populations that are underserved. These are vaccines that the Chicagos of the world really need as soon as possible.”

In just one week, Chicago’s COVID-19 positivity rate has risen from 3.4 percent to 4.6 percent. With new variants popping *up* and guards against the virus coming down, experts point out that in this race, every delay – big or small – matters.

“We had a chance here of getting 15 million people immunized, and we’ve lost that opportunity,” Agus said.

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Health departments don’t typically know how much vaccine shipments they get until the week before. We should have a clearer sense of what those delays will look like early next week.