How contagious is the second new Covid-19 strain? Here is everything we know about this variant so far
Close on the heels of learning about a new coronavirus variant in the UK, a second one has been detected in the country. The second, possibly more infectious coronavirus variant, was first discovered in South Africa. None of the variants have been identified so far in the US. "Ongoing travel between the UK and the US, as well as the high prevalence of this variant among current UK infections, increase the likelihood of importation (of the UK variant)," the US Centers for Disease Control and Prevention (CDC) had cautioned on December 22.
How many cases of the second variant have been detected?
The UK has detected two cases of the second new variant of coronavirus. The cases in London and north-west England are contacts of people who traveled to South Africa over the past few weeks. British health secretary Matt Hancock said that this one is even more contagious than another variant which is currently spreading in England.
"We’ve detected two cases of another new variant of coronavirus here in the UK. This new variant is highly concerning because it is yet more transmissible and it appears to have mutated further than the new variant that has been discovered in the UK," explained Hancock during a briefing, reports The Independent. He added, "Anyone in the UK who has been in South Africa in the past fortnight and anyone who is a close contact of someone who has been in South Africa in the last fortnight must quarantine immediately."
On December 14, Hancock informed that a new variant of coronavirus, which may be associated with the faster spread in the southeastern part of England, has been identified. While the UK and South African variants are different, they share at least one mutation called N501Y, which is in a key part of the virus that it uses to infect the body’s cells.
"They (the two variants) are very different. They do not have a common origin, but they have a few similarities. Both of them have a key mutation in the spike glycoprotein that allows the spike protein, most probably, to bind better to the cells and enter the body. Both of us, in South Africa and the UK, believe that this lineage is much more transmissible than the previous lineage. And we are trying to study that as quickly and as thoroughly as possible," Tulio de Oliveira, director of KwaZulu-Natal Research Innovation and Sequencing Platform (KRISP) at the University of KwaZulu-Natal in Durban, South Africa, told CBS News.
How do they impact people?
Scientists are still trying to ascertain the threat posed by the South African variant. According to UK officials, while the virus in both these cases appears to be more transmissible, at the moment, on current evidence, the actual disease that one gets is no different.
"At the moment, we believe, both in South Africa and the UK, that the severity of the disease is similar. But again, it’s still an open question. But we have no reason to believe that the disease severity is dissimilar. However, if it is spreading much faster, we end up with much more people, just by the sheer number, sick," stated Oliveira, who is part of the team that discovered the new South African variant.
Currently, there is no evidence that the variants cause more severe illness or increased risk of death, or require different treatment. The early signs are that the disease caused by the new variants is no worse, but more data is needed to be sure.
Dr Moncef Slaoui, chief scientific adviser for US’s Operation Warp Speed, said that there is no evidence to suggest that the new Covid-19 variants discovered in the UK and South Africa have a different impact on people. While there is data "suggesting but not demonstrating" that these variants may be more infectious, there is no evidence that their pathogenesis or impact on people is any different than the strains that have been circulating, noted Slaoui.
Scientists are working to learn more about the variants to better understand how easily it might be transmitted and whether currently authorized vaccines will protect people against it. For both the UK and South Africa variants, ongoing research is also looking at how the disease caused by the variants differ from the disease caused by other variants that are currently circulating, whether they cause milder or more severe disease in people, and whether they respond to medicines currently being used to treat people for Covid-19.
Is it normal for viruses to mutate?
Viruses constantly change through mutation, and new variants of a virus are expected to occur over time. Sometimes new variants emerge and disappear. Other times, new variants emerge and start infecting people. Multiple variants of the virus that cause Covid-19 have been documented in the US and globally during this pandemic. The CDC emphasizes that while a variant may predominate in a geographic area, that fact alone does not mean that the variant is more infectious.
What is CDC doing?
CDC is currently monitoring the situation and studying the virus spreading in the US to quickly detect any changes. "In November 2020, CDC officially launched the National SARS-CoV-2 Strain Surveillance (NS3) program to increase the number and representativeness of viruses undergoing characterization. When fully implemented in January 2021, each state will send CDC at least 10 samples biweekly for sequencing and further characterization," explained the agency.
Will vaccines work against the new variants?
Currently, there is no evidence to suggest that vaccines will not work against the new variants, or that they will render vaccines less effective. "We have no evidence at the moment that the vaccine will not work, so actually what that means, in fact, is that there’s strong evidence that it will work because the vaccine produces a strong immune response and it’s broad and acts against lots of variation in the virus," emphasized Susan Hopkins from Public Health England.
Hopkins further elaborated: "What we are doing is laboratory studies with people who have had previous infection and who have had vaccine to look and see in the laboratory how their blood kills the virus. Those take a number of weeks as we grow the virus and do those studies. As soon as they are available, we will of course release them."
What are experts saying?
Jonathan Ball, professor of molecular virology at University of Nottingham, stressed that one needs to study the impact of mutations on virus behavior, but until "we have performed those important experiments we should avoid panicking". "If we practice social distancing and limit interactions with others, then we will avoid spreading the virus, no matter what collection of mutations it has," he added.
According to Lawrence Young, professor of molecular oncology at Warwick Medical School, variants of Covid-19 have been around since the beginning of the pandemic and are a “product of the natural process” by which viruses develop and adapt to their hosts as they replicate. He suggested that along with improved surveillance (testing, tracing, and isolating) and expediting the rollout of vaccines, public health measures will prevent transmission of this variant and any others that will arise.
"Most of these mutations have no effect on the behavior of the virus but very occasionally they can improve the ability of the virus to infect and/or become more resistant to the body’s immune response. The UK and South African virus variants have changes in the spike gene consistent with the possibility that they are more infectious. But the standard measures to restrict transmission (hands, face, space) will prevent infection with this variant,” explained Young.