The New Covid-19 Strain in South Africa: What We Know
Researchers warn that the new variant may spread faster and could reduce the efficacy of vaccines
A new variant of the coronavirus is driving a powerful second wave of infections in South Africa. The variant has already spread to other countries in Africa and Europe and raised concerns over how it will respond to Covid-19 vaccines.
What is the new Covid-19 variant present in South Africa?
It’s normal for viruses to mutate, and variants observed so far in the coronavirus sweeping the globe have made little difference to how it functions. The South African variant, known as B.1.351, has worried scientists because of its unusually large number of mutations, especially in the spike protein, which the virus uses to attach to and infect human cells.
How dangerous is this new variant?
The discovery and spread of the South African variant has coincided with a powerful surge in infections in the country. New daily cases and deaths have already surpassed those seen in the first wave, which peaked in July, and infections are still going up. South African researchers say they also believe that the new variant is more transmissible, since it has quickly crowded out other versions of the virus circulating in the country. Still, they say human behavior—with thousands of South Africans crowding into bars, restaurants and beaches—is likely the main reason for the sharp rise in infections in recent weeks. They are now racing to understand how much more transmissible the new variant is and whether it leads to more severe cases of Covid-19.
Are there any cases of this new variant in the U.S.?
No cases of the South African variant have been detected in the U.S., but that may be because not enough positive test samples have been sequenced. In the past two weeks, laboratories in Finland, the U.K., Australia, Switzerland, Japan and South Korea have found the South African variant in coronavirus tests conducted there. Researchers in neighboring Zambia say the South African variant now also appears to be the dominant virus there.
How is the new Covid-19 variant different from the one discovered in the U.K.?
The scientists who sequenced the South African variant’s genome say it has a mutation—known as N501—that it shares with a separate variant discovered in the U.K. British scientists say that mutation may be responsible for making the variant there much more transmissible.
But the South African variant also has another potentially important mutation, dubbed E484K, that isn’t present in the U.K. variant. Researchers believe that the E484K mutation has changed the shape of the virus’s spike protein, which it uses to attach to and infect human cells, in a way that makes it harder for some antibodies to get a good grip and neutralize the virus. That could have implications on how the variant affects people who have previously recovered from Covid-19 or have gotten a Covid-19 vaccine.
The U.K. variant has been detected in many more countries across Europe, in China as well as in several U.S. states, including Colorado, California, Florida and New York.
Will existing vaccines work against the new variants?
Researchers who have studied the E484K mutation say it may make the existing Covid-19 vaccines less effective against the new variant, but is unlikely to be totally immune to the shots. A reduction in the vaccines’ efficacy could mean that a higher percentage of recipients would still be susceptible to getting Covid-19 or that they might still get a mild form of the disease. It could also mean that a larger proportion of people need to get vaccinated to produce herd immunity and end the pandemic.
What measures are being put in place to handle the new variant?
South Africa has banned social gatherings and closed beaches and parks that are popular during its current summer holiday season. Masks are mandatory in all public places. The government has also prohibited the sale of alcohol, which it says makes people forget about social-distancing rules, and leads to accidents and violence that put more pressure on hospitals. However, restaurants and stores remain open to preserve jobs and livelihoods in a country where many people still live in poverty.
South Africa expects to get its first one million doses of a vaccine developed by the University of Oxford and AstraZeneca PLC this month, with a second shipment of 500,000 doses due in February. The shots, manufactured by the Serum Institute of India, will be given to health-care workers, who have borne the brunt of a surge in new cases of Covid-19.