The latest For people who have been vaccinated against the coronavirus, worry about becoming infected has given way to a new concern: How soon will immunity wane, and will everyone need booster shots? U.S. scientists are studying when those additional doses will become necessary and whether people can get a different brand than their original shots. To answer those questions, researchers are trying to figure out what level of immunity provides protection, how long it takes for immunity to decay to that point and how to best boost that immunity. Nearly half of U.S. adults who have not gotten vaccinated say they are anxious about missing work because of side effects from the shots, according to a poll by the Kaiser Family Foundation released this month. The finding suggests that this concern is a key barrier to immunization, especially for the 25 percent of U.S. workers who do not get paid sick leave. Economic stimulus legislation created tax credits to reimburse employers for providing time off to get vaccinated or recover from side effects, but employers are not mandated to offer that leave. A prominent Japanese physician is warning that a new strain of the coronavirus could emerge in Tokyo if the Olympic Games are held there in July as planned. Naoto Ueyama, chairman of the Japan Doctors Union, criticized the decision to let the competition happen despite rising infections in the country and an increasingly overwhelmed health-care system. With people from more than 200 nations potentially bringing different coronavirus mutations to Japan, he said, "a Tokyo Olympic strain of the virus" could result. After the Biden administration called for a renewed probe into the pandemic's origins, China alleged the move was politically motivated and said the United States needed to let international investigators inspect its own biological laboratories. Chinese Ministry of Foreign Affairs spokesman Zhao Lijian told reporters that the White House's demand for more scrutiny demonstrated that the United States "does not care about facts and truth." He also referenced a U.S. military base that Chinese media has baselessly linked to the coronavirus outbreak. Interest in the pandemic's origins has surged recently, as key evidence remains missing. Ohio announced the first winners of its vaccine lottery, which will award $1 million to five vaccinated state residents and a full scholarship to one of the state's public colleges to five immunized teenagers. Gov. Mike DeWine (R) has earned both praise and criticism for his effort to motivate people to get their shots as the nation's number of new inoculations falls and states lift restrictions. Ohio health officials say the lottery generated a 28 percent increase in the state's vaccination rate in the days immediately after the announcement, though the state's recent overall rate has declined slightly. Other important news In a non–peer reviewed preprint study, German scientists say they have determined the cause of rare blood clots in some people who got the Oxford-AstraZeneca and Johnson & Johnson vaccines. A Tennessee woman was arrested after allegedly driving an SUV recklessly through a vaccination site in protest. U.K. government leaders are pushing back on a former insider's incendiary claim that Britain botched its response to the pandemic and allowed tens of thousands of people to die needlessly. Some people who have struggled with gambling addiction say vaccination lotteries trigger fear that they might relapse. |
Your questions, answered "If we do not know definitively that the vaccines protect against all the variants, how can we meet, even with vaccinated people, without masks and without distancing? How can we know that we are protected?" — Barbara in Florida We understand that new mutations of the coronavirus can sound alarming — after all, scientists refer to some of these as "variants of concern." Researchers continue to be on the lookout for emerging variants, by sequencing the genome of viral samples. But you should feel pretty confident that Food and Drug Administration-authorized vaccines guard against known variants. There is more evidence for that protection than you might think. Multiple studies have examined antibodies and immune cells from vaccinated people, testing those microscopic defenses in a lab to see how they fare against variants. In a report published today in the influential journal Nature, for instance, researchers in Germany and the United States took blood serum from people immunized with the Pfizer-BioNTech vaccine. They pitched the immune fighters in that blood against 22 pseudoviruses, each engineered to mimic a different coronavirus variant. (A pseudovirus resembles the original pathogen, but is far less dangerous to study because it is incapable of multiplying.) Those variants included the B.1.1.7 variant first discovered in the U.K., a variant found in Danish mink, and the B.1.351 variant that emerged in South Africa. In almost all cases, the blood serum from a vaccinated person "efficiently neutralized" the variants, the study authors wrote. What's more, they did not observe any virus able to escape neutralization. That's just one recent example, conducted in laboratory settings. There are encouraging observations from the real world, too. Data from Qatar, for instance, show the Pfizer vaccine blocked infections from the B.1.1.7 variant with 90 percent efficacy and blocked the B.1.351 infections with 75 percent efficacy. It's true that variants appear to somewhat reduce the effectiveness of these vaccines — but the bottom line is vaccines remain strong shields, and especially so against worse outcomes such as severe illness or death. In the Qatar study, there were zero instances of severe covid-19 or death from a PCR-confirmed case caused by either variant, 14 or more days after a second dose. "We should expect a degree of reduction in protection against B.1.351, but not to the extent we should be freaking out about it," John P. Moore, a professor of microbiology and immunology at Weill Cornell Medicine, told The Post this month when discussing the results of a trial of the Novavax vaccine against B.1.351. Francis Collins, who directs the National Institutes of Health, wrote a blog post this week highlighting a study of vaccinated people in Israel. "No evidence was found for increased breakthrough rates of B.1.1.7 a week or more after the second dose," Collins wrote, referring to when a virus is able to surpass — i.e. "break through" — the protection a vaccine offers. In eight cases, people who had been vaccinated tested positive with the B.1.351 variant, but those were within two weeks of the second dose. No fully vaccinated person tested positive for B.1.351, he noted. |
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