The leading US infectious disease specialist, Dr Anthony Fauci, said on Wednesday he foresees America achieving enough collective Covid-19 immunity through vaccinations to regain "some semblance of normality" by fall 2021, despite early setbacks in the vaccine rollout.
Fauci's remarks came during an online discussion of the pandemic with California Governor Gavin Newsom, who announced at the outset that a highly infectious coronavirus variant originally found in Britain has been detected in his state, a day after the first known US case was documented in Colorado.
Newsom said the coronavirus variant B.1.1.7 had been confirmed earlier in the day in a Southern California patient. He did not provide further details.
Fauci said he was "not surprised," adding that additional cases of the variant would likely surface around the nation and that the mutating nature of such viruses is normal.
"They make a living out of mutating. The more you mutate, the more you replicate," he said, saying that the overwhelming majority of mutations are "irrelevant." But, he added, "It appears that this particular mutation does make the virus better at transmitting from one person to another."
However, individuals infected with earlier forms of SAR-CoV-2 "don't seem to get re-infected by this," Fauci said, meaning that any immunity acquired from the coronavirus "is protective against this particular strain."
He also stressed that the so-called UK variant is believed to be no more severe in the symptoms it causes and possesses no special ability to evade the antibodies induced by the newly approved Covid-19 vaccines now in distribution.
Still, the prospect of fighting a more contagious form of the virus comes as the pandemic has raged largely out of control across much of the country for weeks. California, the nation's most populous state, has become the latest flashpoint for the crisis.
'WE'RE GOING TO CATCH UP'
Medical experts attribute the heightened contagion to the arrival of colder weather and the failure of many Americans to abide by public health warnings to avoid social gatherings and unnecessary travel over the year-end holiday season.
The result has been an alarming surge of infections and hospitalizations that have strained the country's healthcare systems to their limits, as well as a steadily mounting death toll, surpassing 338,000 lives lost nationwide to date.
In addition to upending daily social life in America, the pandemic has stifled the economy, idling millions of workers at numbers not seen since the Great Depression of the 1930s.
On Tuesday, President-elect Joe Biden warned that it could take years to inoculate most Americans given an initial vaccine distribution rate that has lagged far behind the promises of the Trump administration. He called on Congress to approve greater funding for the endeavour.
In his comments on Wednesday, Fauci, director of the National Institute of Allergy and Infectious Diseases and an adviser to Biden, said he was confident that early glitches in the vaccine campaign will be overcome.
"As we get into January, the feeling is that we're going to gain momentum to be able to catch up," he told Newsom, saying he expected to reach vaccine "open season," with immunizations becoming widely available to the general public on-demand, by April.
Assuming that the broad vaccination campaign progresses as it should through May, June and July, "By the time we get to the early fall, we will have enough good herd immunity to be able to really get back to some strong semblance of normality - schools, theatres, sports events, restaurants," Fauci said.
Still, the emergence of a more highly transmissible variant of the virus could make a swift rollout of immunizations all the more critical.
The first US case of the UK variant was announced by Colorado Governor Jared Polis on Tuesday. At a news conference on Wednesday, Polis described the patient infected as a National Guard soldier in his 20s who had been assigned to help deal with a Covid outbreak at a nursing home in semi-rural Elbert County, on the outskirts of the Denver metropolitan area.
The director of Colorado's Public Health and Environment Department told reporters that a second member of the National Guard may also have contracted the UK variant, though final laboratory confirmation was still being awaited.
The new variant has been detected in several European countries, as well as in Canada, Australia, India, South Korea and Japan, among others.
The US government on Monday began requiring all airline passengers arriving from Britain - including US citizens - to test negative for Covid-19 within 72 hours of departure.
The government may expand coronavirus testing requirements for international air travellers beyond Britain as early as next week, sources briefed on the matter told Reuters on Wednesday.