U.S. health officials Wednesday announced plans to offer COVID-19 booster shots to all Americans to shore up their protection amid the surging delta variant and signs that the vaccines' effectiveness is falling.The plan, as outlined by the director of the Centers for Disease Control and Prevention and other top authorities, calls for an extra dose eight months after people get their second shot of the Pfizer or Moderna vaccine. The doses could begin the week of Sept. 20.바카라 게임 웹사이트�Our plan is to protect the American people, to stay ahead of this virus,바카라 게임 웹사이트� CDC Director Dr. Rochelle Walensky said at the White House.People who received the single-dose Johnson & Johnson vaccine will also probably need extra shots, health officials said. But they said they are waiting for more data.The overall plan is subject to a Food and Drug Administration evaluation of the safety and effectiveness of a third dose and a review by a CDC advisory panel.Officials said it is 바카라 게임 웹사이트�very clear바카라 게임 웹사이트� that the vaccines' protection against infection wanes over time. They said the U.S. needs to get out ahead of the problem before it takes a more lethal turn.바카라 게임 웹사이트�We are concerned that this pattern of decline we바카라 게임 웹사이트�re seeing will continue in the months ahead, which could lead to reduced protection against severe disease, hospitalization and death,바카라 게임 웹사이트� said U.S. Surgeon General Vivek Murthy.Dr. Mark Mulligan of NYU바카라 게임 웹사이트�s Langone Health center welcomed the announcement as a 바카라 게임 웹사이트�proactive바카라 게임 웹사이트� response to signs that vaccine strength is eroding as the highly contagious delta variant spreads.바카라 게임 웹사이트�Part of leadership is being able to see around the corner and make hard decisions without having all the data. It seems to me that바카라 게임 웹사이트�s what they바카라 게임 웹사이트�re doing here," he said.Top scientists at the World Health Organization bitterly objected to the U.S. plan, noting that poor countries are not getting enough vaccine for their initial rounds of shots.바카라 게임 웹사이트�We바카라 게임 웹사이트�re planning to hand out extra life jackets to people who already have life jackets, while we바카라 게임 웹사이트�re leaving other people to drown without a single life jacket," said Dr. Michael Ryan, the WHO바카라 게임 웹사이트�s emergencies chief.The organization's top scientist, Dr. Soumya Swaminathan, said: 바카라 게임 웹사이트�We believe clearly that the data does not indicate that boosters are needed" for everyone. She warned that leaving billions of people in the developing world unvaccinated could foster the emergence of new variants and result in 바카라 게임 웹사이트�even more dire situations."The U.S. surgeon general rejected the idea that the U.S. must choose between 바카라 게임 웹사이트�America and the world.바카라 게임 웹사이트�바카라 게임 웹사이트�We clearly see our responsibility to both, and we've got to do everything we can to protect people here at home while recognizing that tamping down the epidemic across the world is going to be key,바카라 게임 웹사이트� Murthy said.White House officials noted that the U.S. has donated 115 million doses to 80 countries, more than all other nations combined. They said the U.S. has enough vaccine to dispense boosters to the American people.Israel is already offering booster shots to people over 50 to control its delta surge. And European medical regulators said they are talking with vaccine developers about the idea.Last week, U.S. health officials recommended boosters for some people with weakened immune systems, such as cancer patients and organ transplant recipients. Offering boosters to all Americans would be a major expansion of what is already the biggest vaccination campaign in U.S. history.Some experts have expressed concern that calling for boosters would undermine the public health message 바카라 게임 웹사이트� and reinforce opposition to the vaccine 바카라 게임 웹사이트� by raising more doubts in the minds of people who have been skeptical about the shots바카라 게임 웹사이트� effectiveness.The call for booster shots is a stark reminder that nearly 20 months into the outbreak, the U.S. is still unable to contain the virus that has killed 620,000 Americans and disrupted nearly every part of daily life.Just weeks after President Joe Biden declared the country바카라 게임 웹사이트�s 바카라 게임 웹사이트�independence바카라 게임 웹사이트� from COVID-19 on July Fourth, emergency rooms in parts of the South and West are overloaded again, and cases are now averaging nearly 140,000 per day, quadrupling in just a month.In making its the announcement on boosters, the CDC released three studies conducted during the delta surge that suggest that the COVID-19 vaccines remain highly effective at keeping Americans out of the hospital but that their ability to prevent infection is dropping markedly among nursing home patients and others.One of the studies looked at reported infections in residents of nearly 15,000 nursing homes and other long-term care facilities. It found that the effectiveness of the Pfizer and Moderna vaccines against COVID-19 infection dropped from about 74% in March, April and early May to 53% in June and July.The researchers said it was not clear how much of the decline is attributable to the delta variant and how much might be due to a more general weakening of immunity that could have occurred against any strain.The study looked at all COVID-19 infections, with or without symptoms. The researchers said more work is needed to determine if there was a higher incidence of infections that resulted in severe illness.Another one of the studies looked at 21 hospitals. It found that the vaccine's effectiveness in preventing the need for COVID-19-associated hospitalization was 86% at two to 12 weeks after the second dose, and 85% at 13 to 24 weeks after.The third study, conducted in New York state, found that protection against hospitalizations stayed steady at about 95% over the nearly three months examined. But vaccine effectiveness against new laboratory-confirmed infections declined from about 92% in early May to about 80% in late July.The researchers said they are not certain why the decline occurred, but noted it coincided with the delta variant as well as an easing of social distancing and mask rules.Some scientists had been looking for signs that hospitalizations or deaths are increasing, as a necessary indicator that boosters might be needed.To some leading scientists, the new studies 바카라 게임 웹사이트�would not be sufficient, in and of themselves, to make the case for a booster,바카라 게임 웹사이트� said Dr. William Schaffner, an infectious-diseases expert at Vanderbilt University and liaison to an expert advisory panel that helps the CDC form its vaccination recommendations.___Associated Press writer Jamey Keaten in Geneva contributed to this story.