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Roughly 17 million Americans have received the Johnson & Johnson Covid vaccine, but it will later be said to be the least protective of the options in the United States. But new data shows that the vaccine now prevents infections, hospitalizations and deaths at least as much as the Pfizer-BioNTech and Moderna vaccines.
The reasons are unclear, and not all experts are convinced that the vaccine justifies itself. Yet the accumulating data gives vaccine recipients considerable reassurance and, if confirmed, has broad implications for its rollout in parts of the world.
In Africa, for example, distributing a single dose of vaccine that can be stored in the refrigerator for months is by far the most practical option.
Johnson & Johnson’s at least temporarily shut down the only plant that makes usable batches of the vaccine. However, South Africa-based Aspen Pharmacare, preparing for supply in large quantities to the rest of the continent. only 13 percent Percentage of Africans were fully vaccinated and only 1 percent received a supplemental dose.
“In an African environment where we have to rapidly roll out vaccines, a single dose is very exciting,” said Linda Gail-Bekker, director of the Desmond Tutu HIV Center at the University of Cape Town. Vaccine efficacy in South Africa.
Johnson & Johnson vaccine billed. attractive option For communities with limited access to healthcare, including some in the United States, due to its ease of delivery and mild side effects. But it’s been a bumpy ride.
The shot seemed to have a weaker initial immune response, and the more people who had a single dose of the vaccine, breakthrough infectionsCompared to those who received two doses of Pfizer or Moderna with mRNA vaccines.
Federal health officials in the United States and South Africa in April He paused J.&J. vaccines distribution as they review rare reports blood coagulation disorder in women. The reputation of the vaccine was never fully recovered, although both countries soon resumed use.
But the idea that the vaccine is of poor quality is outdated, some experts said: More recent data show that the vaccine holds up against its competitors.
“J.&J. Dr. “Gail-Bekker was kind of humiliated in people’s minds,” he said. But “it packs a punch over its weight for a single-dose vaccine.”
Up until last June, cumulative data from the CDC showed that vaccination with the Moderna vaccine resulted in the lowest rates of new infections; Those who bought Johnson & Johnson saw the highest rates, and Pfizer-BioNTech was somewhere in the middle.
In the summer, gaps – especially J.&J. and Pfizer – it started to shrink. So far, all vaccines seem to perform equally well against coronavirus infections; actually, Johnson & Johnson seems to hold up a little better.
As of January 22, the most recent data available, unvaccinated people were 3.2 times more likely to become infected than those who received a single dose of Johnson & Johnson vaccine; Those who received two doses of the Moderna vaccine were 2.8 times more likely to become infected and 2.4 times more likely to become infected than those who received two doses of Pfizer-BioNTech. Overall, the Johnson & Johnson vaccine appeared to be slightly more protective against infection than the two alternatives.
Among Americans who received booster doses, all vaccines appeared to have more or less the same efficacy against infection. A booster shot did not add much to Johnson & Johnson’s previous level of protection (although the data does not indicate who received what type of booster).
Data collected by the CDC from 29 jurisdictions representing 67 percent of the population.
“CDC data adds to the growing audience. evidence showing “The Johnson & Johnson Covid-19 vaccine provides lasting protection against breakthrough infection and hospitalization.”
Findings, J. & J. D., a vaccine development specialist at the Fred Hutchinson Cancer Research Center in Seattle. Larry Corey said the vaccine deserves closer scrutiny.
“This vaccine platform may have some surprising features that we didn’t expect,” he said. The data is “interesting, provocative and we should spend more time understanding it.”
Corey said the results matched his experience in HIV research with adenovirus, which forms the backbone of the Johnson & Johnson vaccine. “It has a much longer endurance than almost any other platform we’ve worked with so far,” he said.
Scientists are just beginning to speculate as to why the vaccine’s profile has improved with the passing months.
During the first few weeks after immunization, antibody levels rise rapidly, but then decrease rapidly. J. & J. Some research suggests that the vaccine may produce antibodies that decrease more slowly than those produced by other vaccines. Or these antibodies become more sophisticated over time, through a biological phenomenon called affinity maturation.
Perhaps some researchers suggest that the vaccine offers a more robust defense against the Omicron variant, which is responsible for the large increase in infections over the past few months. And studies have shown that the vaccine trains other parts of the immune system at least as much as the other two vaccines.
Not everyone is convinced that the Johnson & Johnson vaccine has arrived. Natalie Dean, a biostatistician at Emory University, said it may appear to be effective now, as many recipients become infected early and gain additional immunity. “They may have a different immune profile,” she said.
People who get the Johnson & Johnson vaccine but don’t get the vaccine now have a lower infection rate. Dr. Still, Dean noted, the death rate was slightly higher compared to those who had the Pfizer-BioNTech and Moderna vaccines.
But the differences aren’t huge, and they disappeared among those who fired boosters. Dan Barouch, a virologist collaborating with Johnson & Johnson at Beth Israel Deaconess Medical Center in Boston, said the CDC’s statistics on deaths are only available through January 1, and the superiority of the Johnson & Johnson vaccine could only be revealed by February or March data. . in the development of the vaccine.
Deaths tend to delay infections, often weeks or months, because “most deaths are after prolonged hospital courses,” he said.
Dr. For a clearer comparison of vaccines, Dean said he’d like to see data that includes information about individual factors, such as previous infections and other high-risk conditions, rather than the age-adjusted total numbers provided by the CDC.
“It’s a shame we don’t have a more direct study of results among people who take J.&J.,” he said. That’s partly because fewer people get the vaccine than mRNA vaccines, but also because “we rely on other countries producing data,” he said.
Some of this information came from South Africa. In one attempt, called SisonkeGail-Bekker and colleagues evaluated one dose of the Johnson & Johnson vaccine in approximately 500,000 healthcare workers and two doses in approximately 240,000 of these individuals.
In the first part of the study, the researchers matched recipients with a control group based on age, gender, risk factors for Covid, socioeconomic status, and previous Covid infection. They found that when the Delta variant predominated in the country, the vaccine had an effect. about 67 percent effectiveness against hospitalization and about 82 percent death. Protection against the beta variant was similar.
Dr. “Certainly during Beta and Delta waves, a single dose worked very well for severe illness and death,” said Gail-Bekker.
When the Omicron variant began circulating in South Africa, the researchers offered participants a booster of the same vaccine. Less than half agreed.
Dr. “It’s been an outstanding comeback,” said Gail-Bekker. At this point, the perception was that the Pfizer-BioNTech and Moderna vaccines were superior. “We again felt we offered a very second-rate option,” she recalls.
However, the data so far, J. & J. the vaccine had an efficacy of about 75 percent against hospitalization with the Omicron variant, comparable to protection From the Pfizer-BioNTech vaccine. The researchers presented the findings last month at the Retroviruses and Opportunistic Infections Conference in Denver.
Experts suggest that although the trial only looked at people with two doses of the Johnson & Johnson vaccine, the vaccine could be an excellent booster for people who initially had two doses of the mRNA vaccine.
But in December the CDC suggested mRNA vaccines blood clots and Guillain-Barré syndrome. The agency found four cases of blood clots per million people vaccinated; Women aged 30 to 39 had the highest incidence, at about 11 per million.
MRNA vaccines have also been associated with rare side effects. are thought to cause 11 cases of myocarditisor inflammation of the heart, in every 100,000 vaccinated men aged 16 to 29 years.
Dr. Dean said more data on different combinations of vaccines could clarify which ones are the safest and most effective in the long run. The arrival of new variants could give some vaccines an advantage over others, he said.
“I am very open-minded about what the best vaccine regimen might be for the future,” he said.
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