Easier to spread Covid variant in US increases vaccine urgency

Photographer: Eric Lee / Bloomberg

Easier-to-spread variant of Covid-19 first detected in the United States last week could intensify the outbreak of the virus, if not already, heightening the urgency of a faster and larger vaccine surge effective.

Only three states – Colorado, California and Florida – have identified cases of the mutated strain that has been raging in the UK for months. But U.S. health officials say they don’t yet know how far the variant has already traveled in the United States, or what that might mean for the future.

“I suspect it’s more common than we know,” said Michelle Barron, senior medical director of infection prevention and control. UCHealth, a health care system with a dozen hospitals and hundreds of clinics in Colorado. “It’s a function of ‘if you look for it, you will find it.”

The discovery of the mutant strain in the United States comes as the vaccination campaign of most Americans has been hampered by ineffective coordination and a lack of federal support to states and health systems. While more than 4.28 million Americans had been vaccinated by Saturday evening, according to Bloomberg Vaccine tracking is far less than the 20 million doses that U.S. health officials predicted for the end of 2020.

Meanwhile, the number of infections is rising, with nearly 231,000 new cases reported in the United States on Thursday before the holiday weekend, as reports can be sporadic. Four states – including New York and California – have exceeded one million infections in total, and more than 350,000 Americans have died.

“It’s a race, and this variant made the challenge even more daunting,” said Eric Topol, director of the Scripps Research Translational Institute in La Jolla, Calif. “Whatever we have seen in 2020 in terms of a difficult virus, it is going to take it to a new level.”

Vaccine distribution has been a challenge for an American health care system strained by a simultaneous rise in infections. State and local governments grapple with complex logistics of keeping vaccines cold, deciding who should get rapid access, and persuading vaccine skeptics.

To increase the amount of vaccine available, the US government is considering halving the dose of A bullet from Moderna Inc. was given to the 18 to 55-year-olds, said Moncef Slaoui, scientific director of Operation Warp Speed, on CBS’s “Face the Nation”. He said there is some evidence showing that the half dose provides the same level of protection for this age group.

Slaoui’s comments came in response to a question about the UK’s decision to get as many people as possible their first dose of a Pfizer Inc. and BioNTech SE, while possibly delaying a second dose. He said such a change would be a mistake for the United States as it was not supported by test data.

CDC Studies

Meanwhile, the U.S. Centers for Disease Control and Prevention is currently trying to model the effect the variant might have on accelerating the spread, according to Kristen Nordlund, a spokesperson for the agency. At the moment, however, “we have no results,” Nordlund said in an email.

Prior to November, only a number of cases in the United States had been sequenced, a laboratory procedure by which the genetic makeup of the pathogen can be determined as it moves through the population. Since then, however, the CDC has launched a national program to detect new strains, said Greg Armstrong, director of the CDC’s advanced molecular detection program.

The CDC is now evolving Until sequence 750 samples per week, according to Armstrong, and the agency is working in partnership with labs across the country to map the genetic material of about 1,750 virus samples per week.

The agency is also examining whether the mutations could make existing treatments less effective, according to Henry Walke, the CDC’s Covid-19 incident manager. Still, there is no reason why measures such as wearing a mask and social distancing are less effective in preventing transmission of the new strain, he said on a call with journalists last week.

Mutant viruses

Viruses have the ability to change through mutations that occur naturally as they replicate and circulate in their hosts. Some, like the flu, evolve rapidly with thousands of mutations and distinct lineages, while others are more stable.

The new variant, known scientifically as B.1.1.7, contains a large number of mutations, which is unusual, said Andy Pekosz, director of the Center for Emerging Virus and Infectious Diseases at Johns Hopkins University. A particular problem is the change in the spike protein, which binds to human cells, allowing the virus to enter.

Scientists suspect that these mutations facilitate the binding of the spike protein. The new strain is believed to be 57% to 70% more transmissible than other strains of the virus.

Prevalence in UK

In the UK, the new variant was responsible for 62% of Covid-19 infections in London during the week ending December 9, up from 28% in early November, according to Paul Hunter, professor of medicine at the University of East Anglia Norwich School of Medicine. Cases have also been identified in more than a dozen other countries, including Australia, Canada, Germany, Italy, Japan, Lebanon, the Netherlands, Singapore and South Korea. .

In Colorado, state scientists are trying to do full genetic sequencing on all samples that show signs of the British variant, according to state science director Emily Travanty. Samples are reported when only two of the three genes targeted by the benchmark PCR tests used by the state are found, indicating that a mutation has occurred in the third – the critical spike protein.

The missing gene is present, according to Travanty, but made undetectable by the test due to the mutation, making it a signature of the variant, she said. When laboratories discover this red flag, it indicates that further investigation is needed.

A lot of unknown

“We don’t know a lot about this variant,” Colorado Governor Jared Polis said last week after the first US case was discovered in his state. “But if it spreads faster, more people will get it and more people will be hospitalized.”

Still, there are some positive results associated with the variant. It is apparently not more deadly, although if more people were infected there would be more deaths. And we don’t think we can overcome the two vaccines already distributed in the United States, the Pfizer Inc.-BioNTech SE shot, and the Moderna Inc ..

“There is good news here,” Topol said. “It will not affect the effectiveness of the vaccine. That’s why there is this race. If we go ahead and get everyone vaccinated, if we do it quickly, we’ll have this virus under control.

Transmission speed

Meanwhile, in the UK, the extra speed of transmission believed to be linked to the new strain has been noticeable. The number of new cases has increased dramatically in recent weeks, even as the country institutes increasingly strong lockdowns, said Michael Osterholm, director of the Center for Infectious Disease Research and Policy at the University of Minnesota.

In the United States, mask wearing and social distancing have often been more of a political issue than a public health issue, with at least one adviser to President Donald Trump suggesting that herd immunity, which occurs when enough people become immune to a disease making it unlikely to spread, can be achieved by simply letting the disease spread.