如果你愿意，你可以摘下面具遛狗或者和朋友出去吃饭完全接种疫苗来自新冠肺炎。但在任何户外拥挤的活动中，如音乐会、游行和体育赛事，都要保持这种状态。
在室内公共场所戴口罩也是必须的。
那是根据新指南疾病控制和预防中心周二为被认为完全免疫的人发布了这一消息——这是一个里程碑式的事件，发生在一个人最后一次注射疫苗两周之后。
约翰内斯·艾泽勒/法新社通过盖蒂图像
2020年3月5日，纽约时代广场，一名男子戴着面具使用手机。
在周二宣布这一变化的新闻发布会上，疾控中心主任罗谢尔·瓦伦斯基(Rochelle Walensky)表示，最新研究表明，户外传播很少，室内环境造成的风险增加了“20倍”。她说，随着更多的人接种疫苗和病例数量下降，疾控中心计划进一步放宽建议的规定。
瓦伦斯基周二告诉记者:“接种疫苗的人越多，我们就能采取越多的措施，花时间和我们喜欢的人一起做我们喜欢做的事情。”
由于疫苗接种率正在攀升，新的指导方针可能为各州和地方官员放宽口罩规定铺平道路。新的联邦建议包括，接种疫苗的人可以认为自己在教堂、商场购物或去健身房是安全的，尽管疾控中心仍然建议在这些室内环境中戴口罩。
疾控中心表示，敦促谨慎的主要原因是，尚不清楚接种疫苗的人是否会传播病毒。
研究表明，这种疫苗在防止一个人感染后得重病方面非常有效。但是关于他们是否还会携带这种病毒并感染其他没有接种疫苗的人，人们知之甚少。
通过盖蒂图像阅读鹰六/媒体新闻集团
2020年6月5日，宾夕法尼亚州西雷丁，妇女们坐在农舍厨房外的一张桌子旁。
“在公共场所，其他人的疫苗接种状况或他们是否有患严重新冠肺炎病的更大风险可能是未知的。因此，全面接种疫苗的人应该继续遵循指南来保护自己和他人，包括在室内或室外环境或需要口罩的场所佩戴合适的口罩，”疾控中心表示。
该国不到三分之一的人口已经完全接种疫苗，这意味着大部分人口仍处于危险之中。尽管接种疫苗的增加被认为有助于减轻这一流行病的影响——各州报告说，上周接种疫苗的人数下降了近17%——但美国每日平均病例仍接近55，000例。
美国顶尖传染病专家安东尼·福奇博士此前曾表示，他希望看到这一数字每天下降到1万人以下，然后各州才会考虑取消口罩强制令等缓解措施。他说，在那之前，人们可以通过接种疫苗来保护自己。
“即使当你在室内和室外谈论变异时，接种疫苗，你肯定会有一定程度的保护，”福奇周二说。
上个月，瓦伦斯基说，她担心“即将到来的厄运”，因为在假期后的大规模激增之后，病例似乎又开始上升。周二，主任说曲线现在正在“稳定”，她将其归因于疫苗接种人数的增加。但是，她警告说，未来的成功可能因地区而异。
“在疫苗接种率低的地方，我们可能会看到更多的疫情爆发，这就是为什么我认为这真的是，我们必须小心，”她说。
CDC says vaccinated people can ditch the mask outdoors in many cases
You can ditch the mask walking your dog or dining outside with friends if you arefully vaccinatedfrom COVID-19. But keep it on for any outdoor crowded events like concerts, parades and sporting events.
Wearing a mask in public spaces indoors also remains a must.
That’s according tonew guidancereleased Tuesday by the Centers for Disease Control and Prevention for people considered fully immunized -– a milestone achieved two weeks after a person’s final vaccine shot.
In a press briefing Tuesday announcing the change, CDC Director Rochelle Walensky said the latest research suggests transmission outdoors is rare, with indoor settings posing a "20-fold" increased risk. The CDC plans to further loosen suggested rules as more people become vaccinated and case numbers decline, she said.
"The more people who are vaccinated, the more steps we can take towards spending time with people we love doing the things we love to enjoy," Walensky told reporters on Tuesday.
The new guidelines could pave the way for states and local officials to relax mask mandates now that vaccination rates are climbing. Among the new federal recommendations is that vaccinated people can consider themselves safe attending church, shopping at the mall or going to the gym, although the CDC still recommends wearing a mask in those indoor settings.
The primary reason for urging caution, the CDC says, is because it’s not clear whether a vaccinated person can transmit the virus.
Studies show the vaccine is extraordinarily effective in preventing a person from getting seriously ill after becoming infected. But less is known about whether they could still carry the virus and infect others who aren’t vaccinated.
"In public spaces, the vaccination status of other people or whether they are at increased risk for severe COVID-19 is likely unknown. Therefore, fully vaccinated people should continue to follow guidance to protect themselves and others, including wearing a well-fitted mask, when indoors or in an outdoor setting or venue where masks are required," according to the CDC.
Less than a third of the country has been fully vaccinated, meaning much of the population remains at risk. And while rising vaccinations are credited for helping to blunt the impact of the pandemic – states are reporting a nearly 17 percent decline in the last week -- the U.S. daily case average is still nearly 55,000.
Dr. Anthony Fauci, the nation's top infectious disease expert, has said previously that he would want to see that number drop below 10,000 a day before states consider pulling back on mitigation measures like mask mandates. Until then, people can protect themselves by getting vaccinated, he said.
"Even when you're talking about variants, indoors, outdoors -- get vaccinated and you will certainly have a degree of protection," Fauci said Tuesday.
Last month, Walensky said she feared "impending doom" as cases appeared to be back on the rise after a massive post-holiday surge. On Tuesday, the director said that curve is now "stabilizing," which she attributes to rising vaccination numbers. But, she warned, future success could vary by region.
"Where we have low areas of vaccination, we are going to potentially see more outbreaks, which is why I think it's really, we have to be careful," she said.
