专家担心新冠肺炎案例随着新的BA.2变种继续传播，美国的这一数字将在未来几周内上升。
数据来自疾病控制和预防中心的数据显示，BA.2是omicron的子变异体，其患病率每两周增加两倍。
根据CDC的数据，截至3月11日的一周，BA.2占美国所有COVID病例的23.1%，而截至2月26日的一周占所有病例的7.1%。
尽管最初的omicron变异体仍然占美国COVID感染的大多数，但其流行率在同一时期已经从74.5%下降到66.1%。
国家顶级传染病专家安东尼·福奇博士说，鉴于BA.2的日益流行，他预计下个月内病例将会增加。
“我预计我们可能会看到美国的病例有所上升，因为仅在一周左右前，美国疾病控制和预防中心公布了他们对室内掩蔽推荐标准的修改，现在全国大部分地区都在这一地区，不需要室内掩蔽，”福奇告诉美国广播公司下属机构KGTV星期三。
福奇补充说，他相信BA.2将成为该国的主导变体，超过最初的omicron变体。
几个欧洲国家——如芬兰、法国、德国、荷兰和英国——报告称，在过去几周内，新冠肺炎疫情激增。
根据约翰霍普金斯大学的数据，英国周三记录了93，943例病例，是两周前记录的45，303例的两倍多。
“欧洲一直是我们在美国可以期待什么的重要标志，”波士顿儿童医院的流行病学家、美国广播公司新闻撰稿人约翰·布朗斯坦博士说。“不断上升的感染率、变异流行率的增加以及缓慢的加强推广很可能是激增的迹象。是否会是另一波或小的颠簸，我们还不知道。”
上个月，英国首相鲍里斯·约翰逊宣布，英国将放弃任何剩余的新冠肺炎措施，以便英国可以进入疫情的新阶段，他将其描述为“与乔维德一起生活”
几个欧洲国家紧随其后，美国也是如此，放宽了全国70%地区的掩蔽指导，包括学校。
阿纳多卢图片社
2022年2月10日，人们在纽约州的新冠肺炎试验场等待。
福奇说，他对BA.2似乎不会导致更严重的疾病感到鼓舞，但警告说，如果美国经历另一波COVID浪潮，美国人必须愿意采取缓解措施-其他专家也同意这一点。
布朗斯坦说:“我们现在看到的是，随着病例的增加，能够采取干预措施的重要性，以及他们回来后需要如何重新适应。”“这可能意味着在某些环境下进行掩蔽，并减少在室内环境和我们知道病毒会迅速传播的环境中的时间。”
位于西雅图的华盛顿大学健康指标和评估研究所的流行病学家Ali Mokdad博士说，他希望美国政府也有计划分发新冠肺炎抗病毒药物，以防疫情激增。
“这些药物是救命药，如果有人在早期被诊断出并服用了这些抗病毒药物，他们就不会死在医院里，”他告诉ABC新闻。“所以这将真正减轻新冠肺炎的负担。”
COVID cases predicted to rise in coming weeks because of new BA.2 variant
Experts fear thatCOVID-19 casesin the United States will rise in the next few weeks as the new BA.2 variant continues to spread.
Datafrom the Centers for Disease Control and Prevention shows BA.2, which is a subvariant of omicron, has been tripling in prevalence every two weeks.
As of the week ending March 11, BA.2 makes up 23.1% of all COVID cases in the U.S. compared to 7.1% of all cases the week ending Feb. 26, according to the CDC.
Although the original omicron variant still makes up the majority of America’s COVID infections, its prevalence has dropped over the same period, from 74.5% to 66.1%.
Dr. Anthony Fauci, the nation’s top infectious disease expert, said given the growing prevalence of BA.2, he expects cases will increase within the next month.
"I would expect that we might see an uptick in cases here in the United States because, only a week or so ago, the CDC came out with their modification of the metrics for what would be recommended for masking indoors, and much of the country right now is in that zone, where masking indoors is not required," Fauci told ABC affiliateKGTVWednesday.
Fauci added that he believes BA.2 will become the dominant variant in the country, surpassing the original omicron variant.
Several European countries -- such as Finland, France, Germany, the Netherlands and the United Kingdom -- have reported a spike in COVID-19 over the last couple of weeks.
In the U.K., 93,943 cases were recorded Wednesday, according to Johns Hopkins University, more than double the 45,303 recorded two weeks earlier.
"Europe has been an important sign of what we can expect in the U.S.," said Dr. John Brownstein, an epidemiologist at Boston Children's Hospital and an ABC News contributor. "Rising infections, an increase in variant prevalence and a slow booster rollout is likely a sign of a surge. Whether it will be another wave or small bump, we don’t know yet."
Last month, U.K. Prime Minister Boris Johnson announced any remaining COVID-19 measures in England would be dropped so the country could move into a new phase of the pandemic, which he described as “living with COVID.”
Several European countries followed suit, as did the U.S., which eased masking guidance for 70% of the country, including for schools.
Fauci said he is encouraged that BA.2 does not appear to cause more severe disease, but warned if the U.S. experiences another COVID wave, Americans must be willing to readopt mitigation measures -- and other experts agree.
"What we’re seeing now is the importance of being able to off-ramp interventions as cases up and how they need to readopted as they come back," Brownstein said. "This might mean masking in certain setting and spending less time in indoor settings and environments we know the virus can spread quickly."
Dr. Ali Mokdad, an epidemiologist with the University of Washington's Institute for Health Metrics and Evaluation in Seattle, said he hopes that the U.S. government also has a plan to distribute COVID-19 antivirals in case of a surge.
"These medications are life-savers and if someone is diagnosed early on and they take these antiviral medications, they're not going to end up in the hospital and die from it," he told ABC News. "So it will really reduce the burden of COVID-19."
