A South African variant of coronavirus, now also in the UK, is making an existing mutation there more infectious and may even reduce the effect of vaccines.
Image: Tolga Akmen/Getty Images/AFP
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Bad things seldom come alone. In the UK, COVID experts have detected the first cases of a British variant of the virus that is carrying an additional gene mutation seen also in a South African variant.
The cases are causing concern because it is possible that the two negative characteristics could combine.
In Britain, the variant B.1.1.7 has already made the virus more infectious. The South African variant 501Y.V2, meanwhile, carries a mutation called E484K. And that very same mutation — E484K — has been found in Brazilian variants as well, namely, variants B.1.1.33 and B.1.1.28.
Danger even for recovered patients
These mutations are thought to be especially infectious among people under the age of 20 years. They may also hinder the immune system's neutralizing antibodies — either those you would get through vaccination or after surviving a COVID-19 infection — from binding to the virus and doing their work.
It's only possible to know which variants are spreading if samples are widely sequencedImage: Jerome Delay/AP Photo/picture alliance
That means that the vaccines in use may become less effective, offering people less protection. It also means that those people who have recovered from a coronavirus infection may be vulnerable to reinfection.
Authorities in Brazil have reported individual cases of such reinfection, where they detected the E484K mutation.
Sequencing the mutations provides better overview
As the coronavirus progresses, British health authorities have been sequencing samples far more intensively than authorities in other countries, such as Germany. As a result, the UK has a better overview of the variations spreading through the community.
In a study of 200,000 viral sequences, the New and Emerging Respiratory Virus Threats Advisory Group (Nervtag) says it found 11 cases of mutation combinations. They say the evidence indicates that those were not isolated cases. The group suggests that further cases of these kinds are highly probable.
"A worrying development"
"NOT GOOD" is how Eric Feigl-Ding, an American epidemiologist with the Federation of American Scientists, described the situation.
And Julian Tang, a virologist at the University of Leicester, calls the new cases a "worrying development." Tang told the BBC that any further spread of these variants could create a "melting pot" for yet more variants.
Tang said it was now important that people stuck to lockdown rules and that the spread of the virus was slowed — or else the virus would not only continue to spread but also continue to mutate.
Experts are concerned that if these mutations spread and take hold, it will be harder to contain the pandemic.
They are also concerned that if yet more people get infected in a short space of time, health systems, which are already under strain, may collapse altogether.
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Vaccines face renewed testing
Researchers are now testing the vaccines that have been approved, and which are in use, to see how well they will protect people against the mutations and the mutation combinations.
The makers of the BioNTech/Pfizer vaccine say theirs is largely effective against the UK and South African variants.
A competitor vaccine made by Moderna, however, is said to be less effective.
Epidemiologist Feigl-Ding said in a tweet that while Moderna's vaccine was effective against the British variant, it was about six times less effective against the South African variant.
Researchers and producers around the world are working on updating their vaccines to meet the challenges posed by the virus mutations.
But development, testing, approval, production and actual vaccination programs all take time — as we well know.
Coronavirus rules: How much physical distancing is enough?
Physical distancing is important. But a set distance rule does not do justice to the way viruses actually spread, British researchers say. And the CDC warns: Infections can occur after only a few minutes of exposure.
Image: Reuters/M. Darlington
Keep your distance, please!
These are the coronavirus rules as we know them: Keep a distance of 1.5 to 2 meters (5 to 6 feet) from others, observe good hygiene and wear a mask. But this does not do justice to the complex reality of how aerosols spread, researchers from Oxford and London (UK) and Cambridge MA (US) have written in an analysis published in the British Medical Journal in late August.
Image: picture-alliance/dpa/J. Büttner
This much? Or more?
British Prime Minister Boris Johnson has tried to show schoolchildren how it should be done. But what does his gesture mean exactly? Do his fingertips have to be 1.5 meters away from the fingertips of another person? That would be a reasonable interpretation of the regulations. But two arm lengths alone measure 1.5 meters, so distances of 4.5 meters or more could easily result.
Image: picture-alliance/dpa/Evening Standard/L. Young
Are sheep lengths better?
The Icelandic Association of Sheep Breeders has established its own rules: Two sheep lengths are appropriate to avoid infection. One may wonder if face masks are also supposed to be knitted from real sheep's wool. This young shepherd in Senegal may be trying to find out how long a sheep is by pulling its hind leg. The Icelanders already know — exactly 1 meter.
Image: AFP/J. Wessels
Natural spacers
Of course, this could also work. The standard length of a dog leash corresponds pretty exactly to the current coronavirus rules. Could it be a coincidence that a six-foot leash is usually prescribed for places where leashes are compulsory?
Image: picture-alliance/chromorange
Where does the 2-meter rule come from?
The authors led by Lydia Bourouiba, an expert in fluid dynamics and disease transmission at MIT, writes that the rule is outdated. Two meters was the distance recommended by the German physician C. Flügge in 1897. Visible droplets that he had caught within this distance were still contagious. A 1948 study showed that 90% of streptococci coughed out in droplets flew no further than 1.7 meters.
Image: picture-alliance/dpa/PA/Jordan
Two meters are not enough
The 1948 study was published in the American Medical Journal. It also showed that 10% of streptococci flew much further: up to 2.9 meters. If that were the case, perhaps the people on this lawn on the banks of the Rhine in Dusseldorf would be safe — if every other circle remained free. But wait a minute — we are not dealing with streptococci (bacteria) here, but with viruses.
Image: picture-alliance/dpa/M. Becker
Viruses spread via aerosols
Viruses are much smaller than bacteria, so they can float around for hours and spread better in the air. This is why the researchers recommend that the distance between people should not be the only safety criterion but that other factors should be considered, too: How well a room is ventilated, whether people are wearing masks, and whether they are silent, speaking softly or singing and shouting.
Image: picture-alliance/dpa/Bayerischer Rundfunk
Do not sing or cough
Numerous studies have also shown that coughing can propel veritable parcels of viruses up to 8 meters through the air. Speaking or singing loudly also spread a lot of aerosols and droplets about the room. If, however, people only speak quietly, as in a library, and sit in the fresh air, safe distances can be smaller again.
Image: Getty Images/AFP/A. McBride
How long should I stay in the room?
The duration of a stay in a contaminated room and how many people are in that room are also decisive factors when assessing the risk of infection. The researchers have used those factors to develop a traffic light model. The clear result: In rooms with a high occupancy, you should generally stay only for a short time, make sure they are well aired, wear a mask and speak quietly.
Image: picture-alliance/dpa/S. Hoppe
One minute is enough to get infected
Even very brief contact can be enough to transmit SARS-CoV-2. The US Center for Disease Control (CDC) had to tighten its rules on October 21, after a prison guard caught SARS-CoV-2 from prisoners with whom he had only had contact with for a few minutes at a time. Now, "close contact" is defined as being within 2 metres of an infected person for at least 15 minutes cumulatively within 24 hours.
Image: picture-alliance/empics
No mask needed here
Here, however, the traffic light of the UK-US research team would show green. Outside, people can be safe for long periods of time even without a mask, provided there are few people around, everything is well ventilated and no one talks much. But even so, will the distance between deck chairs being measured here be enough?
