Johnson & Johnson COVID vaccine: What you need to know with the single-dose vaccine set to reach Maryland

The U.S. Food and Drug Administration granted emergency use authorization to Johnson & Johnson’s single-dose COVID-19 vaccine on Saturday, a move that would add a third vaccine against the coronavirus, ease the nationwide supply constraints and bring America one step closer to combating the coronavirus pandemic.

Data suggests the vaccine, made by Johnson & Johnson’s Janssen Pharmaceutical Companies, is safe and effective, especially at preventing severe disease, scientists and medical experts say.


The company reports an overall efficacy rate of 66% in preventing moderate to severe cases of the disease caused by the virus. It also reported being 85% effective overall in preventing severe disease and 100% effective in preventing COVID-19-related hospitalization and death.

Shipments to be divided among states could begin as early as Monday. Johnson & Johnson has said that it expects to deliver 20 million doses to the U.S. by the end of March, and 100 million by summer. On Sunday, a U.S. advisory committee will meet to recommend how to prioritize use of the vaccine.


Johnson & Johnson produced its first batch of roughly 4 million doses at its Dutch plant, federal officials said. The Baltimore plant is expected to supply the bulk of its doses for the United States.

Here’s a roundup of frequently asked questions, and answers, as Johnson & Johnson’s vaccine reaches Marylanders.

If I’m offered a Johnson & Johnson vaccine, should I take it, or wait for a more effective one?

There is wide agreement among public health and medical professionals that people should not hesitate to take Johnson & Johnson’s vaccine in favor of other COVID-19 immunizations.

“It’s terrific to have a third vaccine with clear evidence that benefits exceed the risks,” said Dr. Joshua M. Sharfstein, a vice dean in the Johns Hopkins Bloomberg School of Public Health and a former FDA deputy commissioner. “The use of this vaccine should accelerate the progress against COVID-19.”

The latest vaccine offers a high level of protection after just one dose, while Pfizer/BioNTech’s and Moderna’s products call for two doses. Johnson & Johnson’s vaccine can also last up to three months in the refrigerator, whereas the other vaccines must be stored at very cold temperatures. That could potentially make it easier to access and administer, especially in rural areas without freezer capacity.

Dr. Anna P. Durbin, a professor of international health at the Johns Hopkins Bloomberg School of Public Health, said people should not dwell on which vaccine to get, and that it’s difficult to compare the vaccines, which were tested in different places and reported their data differently.

Johnson & Johnson, for example, factored in some of the new, more contagious virus variants into its study, including the one first discovered in South Africa, which the Pfizer and Moderna trials did not originally include. It also studied more non-U.S. citizens than the other two candidates, and measured efficacy at different points in the study.

“It’s like comparing apples and oranges,” Durbin said. “What I would recommend is: Take whatever vaccine you can get. Don’t quibble over which one it is. Take whichever is available. Efficacy numbers ... are not the whole story. We’re really looking for prevention of severe disease, hospitalization and death. All of these vaccines are excellent at that.”


Should anyone in particular get Johnson & Johnson’s vaccine over the other vaccines?

The three vaccines could each be used for those who are eligible, but some have advantages for certain groups over others.

For example, Johnson & Johnson’s single-dose vaccine could be especially beneficial for people who have difficulty taking time off work, and may offer more protection faster than the other two candidates, which require two shots three and four weeks apart.

Johnson & Johnson’s vaccine also might have less severe side effects, Durbin said, potentially making it more desirable for people who can’t take time off or prefer not to experience flu-like symptoms or prolonged muscle soreness.

Ed Singer, president of the Maryland Association of County Health Officers and Carroll County’s health officer, said a single-dose vaccine will make a difference for people who are more “medically fragile,” since it requires only a day’s trip. It may also help increase vaccination rates in rural communities, which have less access to pharmacies, drug stores and medical providers, he said.

Smaller, private medical practices might also benefit more from Johnson & Johnson, he said.

“This is much easier to handle, and not nearly as complicated,” Singer said. “We hope the state will push this out to private providers, people who have relationships with people in their community, and for private pharmacies. If we get Johnson & Johnson, maybe local health departments could get more Pfizer and Moderna, which are more suitable for a mass vaccination effort.”


Durbin said people might feel more comfortable with Johnson & Johnson’s vaccine, which sends a piece of the virus’ genetic code into people’s cells on an adenovirus, a cause of the common cold. The code tells cells to make virus proteins that in turn spark an immune response to fight the virus.

Pfizer’s and Moderna’s vaccine, meanwhile, uses messenger RNA technology, which involves a process that was studied for a long time for other infectious diseases and cancer but not approved.

What if I have an underlying health condition or am statistically more vulnerable to contracting severe COVID-19?

The Johnson & Johnson trials reported that the vaccine candidate was 85% effective in preventing severe disease across all regions studied, 28 days after vaccination in all adults 18 years and older. Efficacy against severe disease increased over time, with no cases in vaccinated participants reported after day 49, according to the company.

Durbin said that means the vaccine works across ages and medical conditions. In fact, the trials found participants with underlying health conditions and those over age 65 fared exceptionally well, she said.

Perhaps most importantly, the vaccine demonstrated efficacy against the new variants, making it a viable option for all interested adults, she added.

“This is going to be highly effective at preventing severe COVID-19, even caused by the South African variant,” she said. “If one were significantly less efficacious, that would be a concern. But when we look at these, they’re all highly efficacious.


“If you can prevent hospitalization and death, you can have a huge public health impact.”

How long will protection last?

Much like with the Pfizer and Moderna vaccines, it is not clear how long immunity from Johnson & Johnson’s product will last.

Scientists are trying to answer that question now and say it’s possible people might need annual shots, just like with the flu vaccine, especially as more variants emerge and become dominant.

The vaccine makers also say they are prepared to adapt their vaccines for the variants if needed, and the U.S. Food and Drug Administration said recently that they would not need to do more expansive human trials.

When will it become available to Marylanders, and where?

Johnson & Johnson said it could provide the nation with 20 million doses by the end of March and 100 million doses by the end of June, though vaccine making is complicated and production issues could hinder the totals.

That would add significantly to the 600 million doses that President Biden recently said would be available of Pfizer and Moderna vaccines by the end of summer, enough to cover most Americans, considering those vaccines require two doses and the Johnson and Johnson vaccine requires one.


How many doses will come to Maryland isn’t yet clear. But Maryland Department of Health spokesman Charles Gischlar said Johnson & Johnson’s vaccine could arrive in Maryland as early as this week.

It was not immediately clear where it would be allocated; Gischlar said in an email that state health officials “are ready to integrate it into our overall distribution plan.”

Bob Atlas, president and CEO of the Maryland Hospital Association, also did not give specifics, but said hospital-based vaccinators would make use of any immunization distributed to them.

“This shot can be given to hospital inpatients before discharge and to rehabilitation or nursing facilities without their needing to return for second doses,” Atlas said in a statement. “Many hospitals will send vaccinators into their communities to take care of people who are home-bound or who face other obstacles to traveling to retail pharmacies or mass vaccination sites.”

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Singer, Maryland Association of County Health Officers’ president, said the local health departments would also be poised to administer Johnson & Johnson should it become available to them.

“We as health departments wouldn’t say no if they decided they wanted to give us Johnson & Johnson,” Singer said. “But it’s probably easier for medical practices and pharmacies than Pfizer and Moderna, which we are already accustomed to handling.”


Spokespeople from CVS Pharmacy and Giant Foods also said they did not have any information to share at this time.

Will Baltimore get extra doses since the vaccine is being produced in the city?

Johnson & Johnson said in April it had contracted with Emergent BioSolutions to produce tens of millions of doses of the vaccine in its East Baltimore plant.

Baltimore Mayor Brandon Scott asked Johnson & Johnson in a letter in early February to tap that stock and directly sell the city 300,000 doses, enough to cover half the population. Scott has been concerned city residents haven’t gotten their fair share despite state mass vaccination sites operating in the city.

Such a sale would bypass the normal process where vaccine is bought by the federal government and allocated to states, which determine where doses go. The company did not comment, but Maryland Gov. Larry Hogan said the city cannot jump the line.

The New York Times contributed to this article.