As the newest coronavirus vaccine makes its debut, the American public has a new set of deliberations before walking into their vaccine clinic — go with the new arrival or stick with the two vaccines that have already gone into the arms of more than 50 million Americans?

The Johnson & Johnson vaccine has a few distinct advantages: only one shot is required and it can hold up in a refrigerator for several months.

Most importantly, the J&J version does very well at keeping people from getting hospitalized and dying. It's 85% effective against severe forms of the disease, which rivals both the Moderna and Pfizer vaccines.

But there's also concern that another topline result may skew perceptions about the shot.

The J&J prevents 66% of coronavirus infections, a finding that comes from a large, global clinical trial that experts caution cannot be easily compared to the roughly 95% efficacy observed with the two other vaccines.

On Thursday, the mayor of Detroit announced he turned down shipments of the vaccine, saying he wanted the "best" vaccines for his city.

"The public is latching on to some of the headline details about these vaccines and that very simple efficacy number, which, as we know, isn't the full story," said Brian Wallace, a captain with the Seattle Fire Department who oversees the city-run vaccine sites.

"I'm sure we'll see people that think they're being given a less effective vaccine," said Wallace, who adds that people already decline Pfizer or Moderna at Seattle's vaccine sites based on misinformation about safety, side effects and efficacy.

Public health messaging around the J&J is especially tricky because the efficacy numbers can obscure nuances about how it was studied. The trials were conducted in different countries during different times of the pandemic than the two other vaccines. And of increasing importance: the J&J was tested in places where new, more dangerous variants of the virus were already circulating.

"These vaccines are all remarkably effective and there isn't sort of a vaccine that's better or worse than any others," said Jason Schwartz, an assistant professor of public health at Yale University.

Some hope the new shot could also help further close the equity gap in the rollout, because it's well-suited for reaching underserved populations that can't easily show up for a second shot or get to a provider that offers the two others.

New arrival

But the J&J rollout will also have to contend with Americans' early impressions, including the chance that some may see it as second-rate. It's a narrative that could gain momentum if the doses appear to target only certain, underserved populations.

"I kind of feel like the two shot would be better... I think it would be more of a boost," said 86-year-old Robert Hampton of Tukwila, Wash., after getting vaccinated at a city-run clinic in Seattle's Rainier Valley, a majority non-white neighborhood hard hit by COVID-19.

Liberty Rothbaum, a Seattle teacher, said she might have hesitated if she had shown up to find only the very newest shot available there.

"That's the only one I was a little worried about... Moderna's been around a little bit longer, but at the end of the day, being vaccinated is the most important thing," she said.

For others, though, the prospect of only one encounter with a needle is a big selling point for the J&J vaccine.

"Yeah, because I'm chicken," said Loretta Orpilla who was accompanied to the Seattle vaccine site by Betty Ragudos.

"Just as long as it works [the vaccine] any one is fine by me," Ragudos said.

Darrel Lewis ended up with the Pfizer shot because the J&J wasn't yet available in Washington and some other Western states.

"I kind of wanted to get the one shot deal, but I just took what was out there," he said.

Shots begin

States only just started doling out the initial 3.9 million doses of the J&J shot, so it's too early to know whether any sizable group of Americans might actually refuse the vaccine, especially when demand for shots still far outstrips supply.

"The vaccine that's available to you — get that vaccine," urged the NIH's Dr. Anthony Fauci at a recent White House briefing.

"There's a place for all three vaccines from hospitals to mass vaccination sites to more local sites and community based clinics," Yale's Schwartz said.

States are dividing up the doses according to their own roadmaps. Some are spreading them evenly among established vaccine sites, while others are focusing more on underserved areas.

In Ohio, the J&J shots also went to more than 200 independent pharmacies.

"There's a little hesitancy anytime something is new," said Aimee O'Reilly, who owns O'Reilly Family Pharmacy in Worthington, Ohio. "They were certainly curious as to the differences, but overall people were excited to get their doses."

In mid-Missouri, Boone Hospital Center gave out its first 1,000 shots of the new vaccine on Thursday.

"We actually had some people contact us and say, 'hey, this was the one I was waiting for, can I get in?' " says the hospital's chief medical officer Dr. Robin Blount.

The federal government has also set aside a share of the first J&J doses for federally qualified community health centers — a welcome infusion for the clinics, which care for people who are lower income and often face barriers to getting vaccinated.

"We're excited to have anything and they're all equal in terms of doing what we need to do," said Dr. Ron Yee, chief medical officer for the National Association of Community Health Centers.

"We're not going to force anybody or try to cajole or convince somebody. We want to give them the information, let them decide."

Yee said the J&J vaccine makes sense for the groups they serve — people who are homebound, unsheltered, moving around for seasonal work or in places without access to transportation — but clinics will get a mix of all three vaccines through the federal distribution program.

"It's not like the health centers are only going to get one vaccine that's superior or inferior to the other ones," he said.

Messaging is key

In Valparaiso, Ind., Beth Wrobel acknowledges that misperceptions about the J&J shot could derail efforts to reach vulnerable groups.

"But I'm actually concerned the opposite is going to happen — will lots of people want the one and done and it goes to rich people?" wondered Wrobel, who's CEO of HealthLinc. "They can take a day off of work, they can make it [for two shots] — our patients' can't."

Wrobel has thought a lot about messaging because her community health center was part of the J&J clinical trial.

"We're going to keep coming back to: no one got hospitalized and no one died, just like the other ones [vaccines]," she said.

The best antidotes to possible concerns about a new vaccine are trust and time, said Teresita Batayola, president of International Community Health Services (ICHS), which serves a large Asian immigrant population in Washington state.

Batayola thinks adding another vaccine is unlikely to backfire, although she hopes ICHS can offer both the Moderna and J&J so patients have a choice.

"People are still more concerned about being protected against COVID-19," she said."It will just increase our capability, we can vaccinate twice as many people with just a one shot dose."

At a recent vaccine clinic in Seattle's International District, none of the predominantly Canotonese-speaking older adults expressed concern about which shot they were getting.

"Patients don't have a preference," said Sunny Hwang, who oversees the ICHS clinic.

Lee, a woman in her 70s, said she followed the government advice to get whichever vaccine you can, as soon as you can.

"Her family, her friends — everyone wants to get a vaccine shot," Lee said speaking through a translator.

Another patient said her relatives were initially nervous about taking any vaccine because of rumors that people would drop dead after getting shot.

This changed as the weeks went by.

"They saw a lot of people get the vaccine, and everything is okay, everybody is fine and then everybody wants to get it," she said.

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