Pfizer and Moderna vaccines, less effective in South African variant

Two of the world’s leading coronavirus vaccines do not work as well against a South African variant, which is more contagious, although both managed to neutralize the virus, two new studies show.

But experts pointed out that the level of neutralization actually needed to protect against the variant remains unclear, and that these latest studies by Pfizer and Moderna were conducted in a laboratory, not in the real world, the Washington Post noted. Both reports were published Wednesday in the New England Journal of Medicine.

Two vaccines against Covid do not work against the South African variant. Photo: Reforma

« These are two in vitro studies, and we do not know if there is a threshold for neutralization that defines protection. In fact, we do not even know if there is a quantitative correlation between antibody levels and protection, » Eric Rubin commented in a podcast. , editor-in-chief of the NEJM. « It is very concerning that we do not know the clinical significance of these findings. »

The two studies used genetically engineered versions of the South African variant in blood samples from vaccinated volunteers, the Post reported. The strain has been identified in many countries, including the United States, along with a variant that was first identified in Britain, which scientists say is highly contagious.

Moderna’s research letter at the NEJM on its COVID-19 vaccine showed a six-fold reduction in antibody levels against the South African variant, according to the newspaper. The efficacy of the vaccine against the variant has not yet been determined.

In laboratory testing of its vaccine against the variant, Pfizer found that the vaccine generated about a third of the antibodies that are generally mobilized against the parent strain. But the activity appeared to be enough to neutralize the virus.

Still, Pfizer said in a statement that it was « taking the necessary steps … to develop and seek authorization » for an updated vaccine or a booster vaccine that can better combat the variant.

In Johannesburg, South African scientists planned to meet on Thursday to discuss the Pfizer study, a spokesman for the Health Ministry told ..

« I do know that our scientists will meet to talk about [el estudio], and that they will advise the minister, « Popo Maja told the news service. » We will not issue a statement until our scientists guide us. We will also allow our regulator to guide us. « 

« Vaccines for all »

Any American who wants a coronavirus vaccine should be able to get it before the end of July, President Joe Biden said this week.

His message, delivered at a . town hall meeting, was more optimistic than last week, when he warned that logistical hurdles likely meant that many people may not have been able to get vaccinated even in late summer. , The New York Times reported.

Separately, Dr. Anthony Fauci, the nation’s leading infectious disease expert, tweaked his own optimistic estimate from last week on Tuesday, predicting the start of a vaccine « open season » in April, according to the Times.

« That timeline is likely to last until mid to late May and early June, » he said in an interview on ..

At a time when Americans are eager to get back to normal, Biden on Tuesday tried to reassure the public.

Although the president said he did not want to make « exaggerated promises », at one point he assured that « I think next Christmas we will be in very different circumstances, God willing, than now. » At another time, he predicted that when the next school year begins in September, the country will be « significantly better off than we are today, » the Times reported.

On Tuesday, the White House also said states would begin receiving 13.5 million doses each week, an increase of more than 2 million doses.

State officials, desperate to vaccinate the most vulnerable Americans before the most contagious variants of the virus become dominant, were delighted by these increases, the Times commented.

The Biden administration has been working with Pfizer to obtain more manufacturing supplies for the company through the Defense Production Act, the Times reported. The administration announced last week that Pfizer and Moderna, the other manufacturer of coronavirus vaccines licensed in the United States, could have delivered a total of 400 million doses by the end of May, a major advance over scheduling.

The latest increase in supply is due in part to Pfizer now receiving the credit for six doses, instead of five, per bottle, a White House spokesperson noted, while two-thirds of the increase comes from an increase in production. Now, authorities also say there is an ample supply of the specialized syringes needed to extract the extra dose of Pfizer.

White House press secretary Jen Psaki told reporters Tuesday that, with the most recent increase, vaccine delivery has grown 57 percent since Biden’s inauguration, the Times reported.

British variant of COVID could be more lethal

More evidence has emerged that a variant of coronavirus, already known to spread more rapidly, is also likely to be more lethal.

The B.1.1.7 variant, believed to have originated in Britain, has already taken root firmly in the US, and could soon become the dominant strain, according to Dr. Rochelle Walensky, director of the Centers. for Disease Control and Prevention (CDC) of the USA.

Speaking on CBS’s « Face the Nation » earlier this week, he said that « we now know, or now estimate, that roughly 4 percent of disease cases in this country are related to B.1.1.7 « , He said. « And we have projections that it could be the dominant strain by the end of March. »

As of Thursday, 1,277 cases of the British variant had been found in 42 US states, according to the CDC.

Walensky’s warning comes shortly after research published by British scientists, showing that B.1.1.7 may trigger more lethal COVID-19 cases.

« The big picture is something like a 40 to 60 percent increase in the risk of hospitalization, and in the risk of death, » Neil Ferguson, an epidemiologist and scientific adviser to the British government, told the Times.

Vaccines already being distributed in the United States are believed to be effective against B.1.1.7, and Walensky said it is imperative that the massive rollout already underway continues. At the same time, and in the face of the other new variants, other measures are being taken, he told CBS.

Drug companies are modifying their research to combat variant B.1.1.7, he clarified, and the CDC is monitoring how people who have already received the Pfizer or Moderna vaccine fare.

« But we are not waiting, » he said. « We are doing scientific work to scale up the different vaccines, in case we need bivalent vaccines (a vaccine that contains two different strains) or booster vaccines. Both are happening. »

As of Thursday, more than 56.3 million Americans had been vaccinated, and 72.4 million doses had been distributed. More than 15.5 million people have received the second dose, according to the CDC.

A global scourge

As of Thursday, the U.S. coronavirus case count had surpassed 27.8 million, while the death toll surpassed 490,000, according to Times calculations. On Thursday, the five states with the most cases of coronavirus infections were: California, with more than 3.5 million cases; Texas, with almost 2.6 million cases; Florida, with more than 1.8 million cases; New York, with more than 1.5 million cases; and Illinois, with more than 1.1 million cases.

Stopping the spread of the coronavirus in the rest of the world remains difficult.

In India, the number of coronavirus cases surpassed 10.9 million on Thursday, a tally from Johns Hopkins University showed. On Thursday, Brazil surpassed 10 million cases and 242,000 deaths, the Hopkins count showed.

Worldwide, the number of reported infections was approaching 109.9 million on Thursday, with more than 2.4 million deaths recorded, according to the Hopkins tally.

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