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The one-time COVID-19 vaccine is effective against serious diseases


The single-shot coronavirus vaccine made by Johnson & Johnson has an 85% effectiveness in preventing serious illness and death, even against new variants of the virus, the company announced in its interim analysis on Jan. 29.

The vaccine has not been so good at preventing more moderate cases of COVID-19, especially in Latin America and South Africa, where variants that have spread more easily have emerged. Depending on the location, the shot was only 72 to 57 percent effective against moderate to severe attacks of the disease.

Other vaccines, in particular the two mRNA vaccines that have emergency use authorization in the United States, have reported overall efficiency levels of up to 95 percent against coronavirus (SN: 18/12/20). That discrepancy may make people resist accepting a less effective vaccine, Anthony Fauci, director of the National Institute of Allergy and Infectious Diseases, said at a Jan. 29 conference call on the results. You shouldn’t, he added.

“If you walk upstairs and say,‘ Well, go to the door on the left and you get 94 to 95 percent (effective vaccine). Go to the right door and get 72 percent. & # 39; Which door do you want to go to? & # 39; “But what people need to understand,” he said, “is that the real importance of the vaccine is to keep people out of the hospital and prevent the more serious complications of the disease.

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That’s what the new vaccine does, said Mathai Mammen, world head of research and development at Janssen, Johnson & Johnson’s pharmaceutical division, during the press conference. “We can prevent COVID in many cases,” he said. “We can prevent hospitalization. In those who contract COVID and have a moderate illness, they have a milder course of illness. No one benefits from this vaccine. "

The Johnson & Johnson vaccine uses a common cold virus – adenovirus 26 – that has been altered so that it cannot replicate in the body and cause disease. The adenovirus carries instructions to convert the coronavirus ear protein into human cells. Human cells produce the ear protein, which triggers the immune system to produce antibodies and trigger the cellular immune defenses of T cells, which attack the coronavirus if found later.

The company used this adenovirus system to make a vaccine against Ebola, as well as still experimental vaccines against Zika, HIV and respiratory syncytial virus or RSV. The use of adenoviruses as carriers or vectors has also been used for COVID-19 vaccines manufactured by Oxford University with AstraZeneca, the Canadian-Chinese company CanSino, and for the Russian vaccine Sputnik V (SN: 23/11/20; SN: 21/07/20; SN: 8/11/20).

Johnson & Johnson tested their vaccine on 44,325 adults in Argentina, Brazil, Chile, Colombia, Mexico, Peru, South Africa, and the United States. Among the participants, 468 cases of COVID-19 arose, the company and the U.S. National Institutes of Health each reported in press releases.

Deaths occurred in the placebo group, but none in the vaccine group. But the company refused to give a specific number of cases and deaths in both groups until it applied for emergency use authorization with the U.S. Food and Drug Administration. That presentation could arrive next week.

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The effectiveness against moderate to severe diseases varies by region, ranging from 72 percent in the United States to 66 percent in Latin America and 57 percent in South Africa. Overall, the vaccine is 66% effective in preventing moderate to severe disease. The vaccine has been equally effective in young adults and people aged 60 and over and in people with or without underlying health problems, such as obesity, type 2 diabetes and other conditions that increase the risk of complications from COVID-19 (SN: 4/22/20; SN: 20/03/20).

At first glance, the declining effectiveness in Latin America and South Africa may seem daunting, Mammen said. More transmissible variants of SARS-CoV-2, the coronavirus that causes COVID-19, have been discovered in Brazil and South Africa.

The South African variant, known as 501Y.V2 or B.1.351, has caused special concern for both its greater transmissibility and its ability to evade some antibodies that provide protection against coronavirus. But the vaccine protects against the most serious consequences of the disease even against those variants, Mammen said. "Not a single South African after 28 days after vaccination ended up needing to go to the hospital. No vaccinated South Africans died."

The other companies conducted their studies at a different stage of the pandemic before the new variants appeared, so the numbers aren’t really comparable, Mammen said. "The pandemic has changed." Now, "most cases come from an evolved set of viruses."

Novavax, a company based in Gaithersburg, Maryland, announced on January 28 that its protein-based vaccine prevents disease with an 89 percent effectiveness, but was also less effective against the South African variant (SN: 28/01/21 ). On the same day, South Carolina officials announced that two unconnected people with no travel history had contracted the South African variant. That finding probably means that the variant is circulating undetected in the state and elsewhere in the country.

Despite the lower efficacy, the Johnson & Johnson vaccine has some advantages over mRNA vaccines. It is given in a single dose instead of two, so you can vaccinate twice as many people with the same number of doses. It should be refrigerated, but not frozen as these vaccines do (SN: 20/11/20). And the vaccine has milder side effects than the already authorized Moderna and Pfizer. Some people had fever, fatigue, or pain at the injection site after inoculation, but “the vast majority of people felt nothing,” Mammen said.

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Other public health officials and scientists point out that coronavirus vaccines are more effective than many vaccines approved for other diseases.

“We would hold a seasonal flu vaccine with 60 percent effectiveness,” Jay Butler, deputy director of infectious diseases at the U.S. Centers for Disease Control and Prevention, said Jan. 29 during a press conference sponsored by the Infectious Diseases Society of America. "While it's disappointing compared to the 95 percent effectiveness of the phase III trials of the two mRNA vaccines before these variants appeared, it's still not something that makes me want to not use or receive the vaccine myself."

Johnson & Johnson says it could produce 1 billion doses of its COVID-19 vaccine, enough to vaccinate about a eighth of the world's population – by the end of the year. That includes 100 million doses promised to lower-income countries through the Vaccine Alliance, or Gavi, and the World Health Organization’s COVAX program. The United States has a deal for 100 million doses, with an option to buy 200 million more doses.

If authorized by the FDA and other regulatory agencies around the world, the vaccine could be an important public health tool, which is crucial as more contagious variants of the virus continue to emerge, experts say. “This virus will continue to evolve and mutate for sure,” Fauci said. That was an incentive to use all available vaccines, safe and effective, he said. "The best way to prevent a virus from evolving is to prevent it from replicating, and do it by vaccinating people as quickly as possible."

Personal writer Jonathan Lambert contributed to this story.



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