While U.K. Health Secretary Matt Hancock raised alarm bells this week by saying the COVID-19 variant first identified in South Africa was a bigger problem than the new variant detected in the U.K., health experts say there's more to the story.
"The thing we’re trying to highlight is that evolution of the virus is not unexpected," said Dr. Richard Lessells, an infectious disease expert researching the variant in South Africa. "We expect this because we are allowing this virus to spread at quite high levels."
As of Jan. 5, the variant that originated in South Africa has been detected in six other countries -- the U.K., France, Switzerland, Japan, Austria and Zambia -- according to the World Health Organization. The variant first detected in the U.K. has been reported in 40 countries and territories.
MORE: Pfizer COVID-19 vaccine likely to work against new, rapidly-spreading variants: StudyPart of the reason new virus variations were first detected in the U.K. and South Africa may come down to surveillance. In the United States, for example, there's no comprehensive system, meaning not all states are doing rigorous virus surveillance, Lessells explained. "It’s quite likely," he added, "that by now different variants are spreading in different parts of the world, but they may not be detected early, depending on how good your genomic sequencing is."
What we know about the variant detected in South Africa
Known as 501Y.V2, it was detected through routine surveillance done by a network of laboratories in South Africa, which found the new variant in 200 samples from 50 different health facilities.
"What was striking was the number of mutations," Lessells said. There were more than 20 mutations, significantly more than other viruses circulating at that time, he said. Even more striking was how seven or eight of those mutations were in the virus' spike protein, "the bit of the virus that hooks onto receptors on our cells and allows the virus to enter."
The 501Y mutation, which makes it easier for the virus to attach to cells and enter them, potentially created a more transmissible virus. "That’s becoming apparent now," Lessells said of the 501Y.V1 (U.K.) and 501Y.V2 (South Africa's) variants. "There is now quite good evidence that these both spread more efficiently from person to person."
While the new variants have not been shown to cause more severe disease or be more deadly, a more transmissible virus carries other risks -- faster spread could trigger more hospitalizations, further straining health care resources.
Daniel Bridges, a Zambia-based public health researcher at the nonprofit PATH, noted that focusing on whether the new variant is more deadly may understate its potential danger.
"It is likely that a modest increase in transmissibility with the same case fatality rate will result in more deaths than a modest increase in virulence with the same transmissibility," Bridges said.
Will current vaccines protect against the new variant?
As for whether our current slate of vaccines will protect against 501Y.V2, Lessells said that "we’re concerned, but we think it’s unlikely that it would completely knock out these vaccines."
Bridges pointed to the importance of having multiple vaccines on the market. "Hopefully, at worst, it will only affect a limited number of vaccines and/or it will only reduce efficacy rather than ablate it," he said.
Early research seems to support scientists' gut feeling about current vaccines remaining effective.
A study released Friday by researchers from Pfizer and the University of Texas Medical Branch found that the Pfizer vaccine remained effective against one of the shared mutations, 501Y, in the 501Y.V1 and 501Y.V2 variants. And researchers there believe it will be effective against both variants despite having more mutations not accounted for in the study -- more studies on the actual variants are still needed.
While the research, which analyzed blood samples from vaccinated participants in Pfizer's clinical trial, has not yet been peer-reviewed, it's a hopeful sign.
For those sickened by COVID-19 who now have antibodies, protection against 501Y.V2 is less certain.
"Natural immunity is different from vaccine immunity," Lessells explained. In some people, natural immunity offers narrow protection compared to vaccines, which tend to trigger a broader immune response, he said. While more research needs to be done, "it raises concern about people being reinfected by the virus."
What's next: Vaccine rollout as the virus evolves
This week, Dr. Scott Gottlieb, a former commissioner of the Food and Drug Administration who now sits on Pfizer's board, pushed for the U.S. "to quicken the pace of vaccination," in an interview with CNBC.
"The vaccine can become a backstop against these variants really getting more of a foothold here," Gottlieb said.
MORE: Rich countries are hoarding the COVID vaccine: ReportWith COVID-19 spreading unabated across the country, the potential for even newer virus variants to evolve in the U.S. may eclipse fears of 501.V2 and 501.V1.
"Vaccines introduce evolutionary pressure," Lessells said. "Variants that can escape vaccines are more likely to spread. That’s why it’s critical that where vaccines are being rolled out it’s done at speed."
"Now is the time to double down on efforts to interrupt transmission and give the virus less chance to mutate," Bridges said. There's nothing unfamiliar we need to do to interrupt transmission, he added. Fundamental practices like social distancing, mask wearing and handwashing are all key techniques.
A Joe Biden spokesman said in a statement on Friday that the president-elect wants to deploy as many vaccines as possible as quickly as possible, contrasting with Operation Warp Speed tactics that included holding some back enough to make sure everyone who gets a first vaccination gets a second.
Access to the vaccine remains a concern in South Africa, where more than 1.1 million people have been infected with and 31,809 have died from the virus, according to data from Johns Hopkins University. South Africa's first COVID-19 vaccine purchase was announced Thursday. The 1.5 million doses of AstraZeneca, imported from India, will start being distributed to health care workers later this month.
In response to widely spreading 501Y.V2 variant, which is now dominate among infections in South Africa, the country has enacted strict measures banning indoor and outdoor gatherings, a curfew and a ban on alcohol sales.
"It is clear that there is a major [vaccine] supply issue for the African continent as a whole and needs to be addressed if global control is to be achieved," Bridges said.
ABC News' Sony Salzman contributed to this report.
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