And then there were three vaccines

UPS driver Juliett Watson’s truck carried a special delivery on Monday when it left a production facility in Shepherdsville, Ky. Her job was to drive carefully packed boxes of the first Johnson & Johnson COVID-19 vaccines 30 minutes north to Muhammad Ali International Airport outside Louisville. It’s set to be the first of many deliveries from the warehouse.

“I’m happy that there’s more vaccinations coming out,” Watson told the Louisville Courier-Journal. “We definitely need them. There’s a lot of people out there struggling.”

The U.S. Food and Drug Administration on Saturday granted emergency use authorization to Johnson & Johnson’s shot, developed by its subsidiary Janssen Pharmaceuticals. It’s the third COVID-19 immunization available in the United States, and it could speed up the vaccination effort. But the arrival of the single-shot formula also raises fresh questions about which version people who want the vaccine should take.

Pfizer and Moderna have been distributing their COVID-19 vaccines in the United States since December. Both employed cutting-edge mRNA technology to stimulate the body’s immune system to combat COVID-19.

Johnson & Johnson took a different approach. To engineer its viral vector vaccine, researchers placed a bit of the coronavirus’s genetic code into a harmless adenovirus. Once injected, the engineered bits of virus provoke the body to create antibodies to ward off a COVID-19 infection. Though the Johnson & Johnson vaccine uses portions of the coronavirus’s DNA, it can’t cause sickness, and the adenovirus host can’t replicate in the human body.

The new vaccine requires just a single shot, rather than Pfizer and Moderna’s regimens of two-doses several weeks apart. The simplified one-and-done approach could appeal to many on the fence: About a quarter of people taking a wait-and-see approach to immunization said they’d be more likely to take a shot that only needed a single dose, according to research from the Kaiser Family Foundation.

But results in efficacy trials have muted some enthusiasm. Johnson & Johnson said its formula was 66 percent effective at preventing moderate cases of the disease four weeks after being administered. Trials indicated the vaccine prevents severe illness 85 percent of the time. The Pfizer and Moderna vaccines reported close to 95 percent efficacy.

Some, like Scripps Research Translational Institute Director Eric Topol, called the results disappointing. But Johnson & Johnson officials took a more optimistic tone. “In a pandemic, if you can, with a single-dose vaccine, very quickly eliminate the severe consequences of death, hospitalization, and severe disease, that’s what’s important for society,” company chief scientific officer Paul Stoffels told Stat News. The top U.S. infectious disease official, Anthony Fauci, told NBC’s Meet the Press he would take whichever vaccine he could get his hands on first.

The Johnson & Johnson formula’s side effects seem largely comparable to other COVID-19 vaccines’: irritation at the injection site, headache, weariness, muscle aches, nausea, and fever. Like other vaccines, there is also the small chance that some people will have an allergic reaction. Many people who have received the Moderna shot have reported mild and moderate side effects, and Pfizer recipients described similar experiences.

The decision for some Christians may be more complicated. Johnson & Johnson relied more heavily on fetal cells derived from abortions than Pfizer or Moderna. While the other two used them only in testing, the latest vaccine incorporated the cell lines in development and production, as well.

The Archdiocese of New Orleans on Friday encouraged Catholics to avoid the Johnson & Johnson vaccine, calling it “morally compromised.” In April, an ecumenical group of Christian leaders, including Southern Baptist Ethics and Religious Liberty Commission President Russell Moore, signed a letter singling out Johnson & Johnson’s formula as “problematic.” The Vatican has taken a softer tone: While it did not condone researchers’ use of fetal cell lines, it declared it “morally permissible” for Catholics to receive a COVID-19 vaccine that relied on the technique.