The discovery of several new variants of the coronavirus that can spread more easily, including a mutation that took place in the Bay in December, makes it even more urgent to rectify the country’s difficult vaccination solution – before the developing virus causes a new upsurge. or learn to evade vaccines.
During the year-long pandemic, public health experts advised that beating the virus was a marathon, that it would take many months of commitment to social distance measures to win. This is still true. But in many ways, the race has intensified over the past few weeks: between a virus spreading new mutations that may make it harder to contain and a vaccination campaign marked by repeated whispers.
“We are now really busy with a race,” said dr. Charles Chiu, the UCSF virologist, said that identified the L452R variant that was blown up in parts of the Bay last month. “It increases our urgency to vaccinate the population en masse before additional variants develop and emerge.”
One worrying aspect: the more the coronavirus circulates in the community, the more likely it is to change and develop into new variants. And there have never been more viruses in California and the United States than now – and many other countries are also struggling to curb them, creating more risk in an interconnected world.
‘By turning the virus around, we’re accumulating a lot of mutations. And some of them can be beneficial for the virus, ”said Dr. Catherine Blish, an expert on infectious diseases at Stanford, said. ‘The best thing we can do at the moment is to deliver the vaccine to as many people as possible as quickly as possible to reduce the total infection burden so that we accumulate fewer mutations.
“We can not stop the virus from mutating,” she said. “But here we can really get the upper hand.”
The US, and specifically California, is in a tight spot in the pandemic. The country passed 400,000 deaths due to COVID-19 on Tuesday, and in California, daily cases and deaths have been overwhelmingly high for weeks.
Meanwhile, the vaccination campaign that the country needs to escape the pandemic is riddled with problems, both at the state and national levels – most recently with 330,000 doses of Moderna taken out of circulation in California due to concerns about allergic reactions.
A new variant, or more than one, has the potential to aggravate a bad situation. If a more contagious version of the virus takes over, it can revive a boom that is just beginning to flatten out. And it could potentially undermine the immunization efforts if the vaccines are less effective against it.
The immediate threat to the Bay and the rest of the state by new variants is not yet clear. The highly contagious B117 variant, which is widespread in the United Kingdom, has been identified in Southern California, but only in a few dozen cases. But the Centers for Disease Control and Prevention warned last week that the variant could become the dominant version of the virus in the U.S. as soon as March, and that it could cause a huge increase in cases.
The L452R variant, whose presence was announced in California on Sunday, appears to be gaining ground in parts of the state and has been linked to several major outbreaks in Santa Clara County, but scientists are not sure if it is more contagious than the virus. . type that has so far spread in California. If L452R turns out to be more contagious, it’s unclear how the competition between him and the B117 variant would play out.
The B117 variant cannot evade vaccines, but scientists do not know about the L452R variant. None of them seem more serious due to disease – although a more contagious virus would inevitably cause more disease and death.
The emergence of the two new variants in California, along with two more spread in other parts of the world, raises new concerns about the mutations that may still occur or are already here and simply have not yet been detected. Experts believe the advent of these variants makes it clearer than ever that the pandemic must be curbed quickly.
“With 3,000 or 4,000 people dying a day (in the United States), we were already in a race with the virus we knew, and now we’re going to add another element,” said Dr. Robert Wachter, chairman of the department, said. Medicine at UCSF. ‘It’s like you’re in a race and the person you are racing against is suddenly 50% faster.
“Once we had two incredibly effective and safe vaccinations, it was really how fast you can get them into people’s arms,” he said. “Not just because of the threats that were obviously obvious, but the emerging threats that will come out the longer it lasts.”
The coronavirus, like all other so-called RNA viruses, mutates frequently. But the COVID-19 virus tends to mutate at a slower rate than many other viruses, taking on only one or two mutations per month. Most of the mutations have little or no effect. Some make the virus less likely to survive. Other mutations make it slightly more or less contagious. Or it changes the way the virus interacts with the body’s immune system, making it a more challenging target for natural immunity or a vaccine.
When enough mutations build up, a new variant emerges that is genetically separate from its parent and behaves in a remarkably different way. The B117 variant has 23 mutations and is much more contagious than the older one. Another variant found in South Africa also appears to be easier to spread.
The L452R variant has five mutations. Experts of infectious diseases are concerned that it can also be more contagious, if only because of how quickly it is taken in the region and other parts of the state. But they do not yet know how the mutations affect their behavior.
That so many variants are detected in such a short sequence raises another overarching concern: this coronavirus mutates faster than most scientists thought. This is probably due in part to simple math – there are currently so many viruses in the world spreading, even at a slow mutation rate.
Public health experts say there is currently no evidence that the new variant is not susceptible to the vaccines. But laboratory tests suggest that some variants, including L452R, have a mutation that could make the vaccines less effective. Much more research needs to be done, Chiu and others said.
The good news is that the vaccines currently in use can be easily adapted to adapt to a new variant, said infectious disease experts. However, this is not an ideal situation – it would complicate an already chaotic vaccination campaign. And it will require a lot more aggressive oversight to identify new variants and determine how well the vaccines work against it.
The experts in infectious diseases say the possibility that a variant that evades the vaccines may become clearer as more people are vaccinated. Vaccinating humans puts pressure on the virus to mutate for its survival. Random mutations that allow the virus to escape through the vaccine will be preferred – and will likely be repeated.
“If you have a virus in circulation that is now undergoing immune control (from a vaccine), you will be much more likely to help develop variants that will adapt and grow better,” said Dr. Melanie Ott, director of the Gladstone Institute of Virology, said. , an independent research group in San Francisco.
It also means that a clumsy vaccination program that leaves large gaps in protection could make it more likely that a variant would emerge that could evade the vaccines, she said. A large part of the world has not yet had access to the vaccines, so even if the United States tamed the virus, they would have to be vigilant about the virus arriving across borders.
Until the herd immunity is reached and the virus stops circulating, variants will remain a problem.
‘If we are too slow, we may have variants that may be less sensitive to the vaccine. “We will have the situation where the vaccine is partially inactive,” Ott said. “We need to get as many people vaccinated as quickly as possible so that we spread as few viruses as possible.”
Erin Allday is a staff writer for the San Francisco Chronicle. Email: [email protected] Twitter: @erinallday