According to a study published on Sunday, April 19, on the health sciences research website medRxiv, the coronavirus or CCP Virus has mutated into at least 30 different genetic versions.
The results arrived at by a group of researchers from Zhenjiang University in Hangzhou, China, showed that so far health officials have greatly underestimated the virus’s ability to mutate.
The team of experts, led by professor Li Lanjuan, found that different strains of the virus have affected different parts of the world, making it more difficult to find an overall cure.
As Li stated in the research paper, “Sars-CoV-2 has acquired mutations capable of substantially changing its pathogenicity.”
The study focused on analyzing 11 randomly selected patients infected with different strains of coronavirus in Hangzhou, where 1,264 cases have been reported, then analyzed the ability of those strains to infect and kill cells. The analysis detected 30 mutations in the virus, 19 of which had been previously discovered.
According to the New York Post, some of the more aggressive strains of the virus could generate 270 times the viral load of the weaker strains. The more aggressive strains also killed human cells faster.
In a previous study published on March 3 in the National Science Review, a team of Chinese researchers analyzed the genomes of 103 patients with coronavirus and found two types of virus strains that were classified as type ‘S’ and type ‘L’.
According to the study, the type ‘L’ strain was considered the most aggressive, which was also found in 70% of the samples analyzed. It was also found that its prevalence decreased after the beginning of January.
The experts pointed out that currently the most common and oldest type of strain is the ‘S’, because according to the experts, the ‘L’ type ended up reducing its capacity to spread due to the containment measures implemented in different countries.
However, Nathan Grubaugh, an epidemiologist at the Yale School of Public Health, called the conclusions “pure speculation,” arguing that the mutations referred to by the study’s authors were particularly small, on the order of a couple of nucleotides, the basic components of genes, but SARS-Cov2 has approximately 30,000 nucleotides, Live Science reported.
Therefore, Grubaugh insisted that those small changes studied, which point to the existence of different strains, are “inaccurate.” Regarding the sample of 103 patients, he said, “It’s a very small sample set of the total virus population.”
Richard Neher, a biologist and physicist at the University of Basel in Switzerland, wrote on Twitter that the Chinese researchers’ findings of double mutation of the virus strains were probably due to a “statistical artifact.”
In doing so, the scientist wanted to point out that such a statistical effect was probably due to early sampling of the ‘L’ group in Wuhan, which would result in an apparently “higher” mortality rate.
Neher also pointed out that when there is a local, fast-growing outbreak, scientists rush to take samples from patients’ genomes of the virus, resulting in over-representation of the various variants of the virus.
The authors acknowledged that the data in their study is “still very limited” and that a more extensive data set needed to be followed up to better understand how the virus evolves.
On Feb. 18, Grubaugh published a commentary in the journal Nature Microbiology indicating that it was a normal condition for a virus to mutate during disease outbreaks.
“We shouldn’t worry when a virus mutates during disease outbreaks,” he said. “Mutations are a natural part of the virus life cycle and rarely impact outbreaks dramatically,” he added.
According to Live Science, viruses whose genetic structure is made up of RNA rather than DNA, as well as SARS-Cov2, are constantly mutating and do not have the mechanisms to correct such errors.
The Nextstrain collaborative project, which involves laboratories around the world through the analysis of genetic sequences studied in infected patients, has indicated that the virus has been mutating every 15 days on average as the pandemic evolves in the world.
As a National Geographic article indicates, the genetic changes the virus is undergoing have provided information for researchers to discover how it has spread in different countries.
“These mutations are completely benign and useful as a puzzle piece to uncover how the virus is spreading,” said Trevor Bedford, a computer biologist at the Fred Hutchinson Cancer Research Center in Seattle.