COVID-19 may be the worst health crisis the world has ever seen – and the virus is getting worse.
The worrying variants (VoCs) are modified versions of the original strain of the SARS-CoV-2 virus, which causes the disease.
The new coronavirus, like other viruses, replicates when it enters the host’s cells. But not all copies are the same. Errors in the replication process, called mutations, give rise to slightly altered viruses.
“Some of these mutations happen because they give the virus a survival advantage, while others don’t,” said Nazeem Muhajarine.
Muhajarine is an epidemiologist at the University of Saskatchewan who studies COVID-19 and variants.
He told Global News that more mutations occur when the virus is in an immunocompromised host and when it can infect many people.
In the first case, the immune system of the immunocompromised person is unable to rid the body of the virus, or to do so quickly. This gives the virus more time to infect more cells and produce more copies of itself, potentially producing more mutations.
It is similar when many people in a population are infected. The virus may spend less time on a single host before the immune system reacts, but it has more opportunities to mutate in more bodies.
Viruses are constantly changing and new variants are constantly emerging. But some changes are exceptional.
“These are the ones that we are particularly concerned about, the variants with the mutation that can give them the advantage of escaping, of escaping the natural immunity or immunity conferred by the vaccine,” said Muhajarine.
Mutations can also confer the ability to become more transmissible, making it easier for the virus to infect others, or more serious, meaning that those infected are more likely to need hospital care or die.
The names given to the variants are an important part of the tracking. The letters and numbers in the name tell researchers that part of the virus has evolved and, hopefully, gives them a good indication of where to look for other strains of concern.
Variant B.1.1.7, first detected in the United Kingdom, is more transmissible and more serious. Muhajarine told Global News that the first data show that the risk of hospitalization, intensive care and death increases.
The B.1.351 strain, found first in South Africa, is more transmissible, but probably not more serious than the original virus – at least as far as scientists know now.
The P.1 strain, seen for the first time in Brazil, appears to be much more transmissible. Muhajarine said that some data from Brazil show that it can be twice as transmissible than the original strain of the virus, known as the “wild” strain.
Scientists do not know if it is even more serious, but preliminary data shows – worryingly – that it seems capable of escaping immunity and reinfecting some people who already had COVID-19.
Then there is the B.1.167 strain, circulating in India. The World Health Organization has not yet classified it as VoC. For now, it is a variant of concern, but Muhajarine wrote, in a follow-up email, that WHO is likely to reclassify it as researchers collect more data.
This is the strain often called the “double mutant”.
Dr. Cory Neudorf, also an epidemiologist at the University of Sasktachewan, said the strain has two mutations seen in other variants that scientists have linked to increased transmissibility and better immune system evasion. But he added: “It is still too early to say whether … it has two of these mutations at the same time is a more worrying issue or just an interesting one.”
Neudorf emphasized that the researchers are still collecting data and said that it can be difficult to make concrete determinations about viruses that are so new. Many of the worrying variants have only emerged in the past few months.
He pointed to the trend of younger people around the world needing hospital care. This may indicate that the variants are much more serious than the original strain of the virus or it may be because the elderly have been vaccinated and have immunity.
The information will continue to emerge as the researchers continue their work, but one thing remains certain.
“Viruses cannot mutate unless they spread,” said Neudorf.
But even with people being vaccinated, Neudorf warns that we are in a precarious time.
COVID-19 is still spreading, and since only part of the population is vaccinated, he says there are likely to be more variants, and they may be even worse than the ones we have now.
“It is possible to continuously obtain new viruses that are mutating within the non-immunized ones, exposing the immunized ones. Eventually, one of these will emerge that could bypass the vaccine. “
He also warned of a potential “high consequence variant”, when a new strain has a combination of resistance or immunity to vaccines, is resistant to treatment, is highly transmissible or is more severe, to the extent that it is difficult for medical staff to diagnose .
“Perhaps it has changed so much that our diagnostic tests do not work, or the vaccine’s effectiveness is now very reduced or has become much more serious, avoiding all of our treatments,” he said.
He stated that there are still no variants in this group.
Neudorf and Muhajarine said the best way to prevent the virus from mutating is to wear a mask, stay physically away, stay at home as long as possible and get vaccinated as soon as possible.