SAN FRANCISCO — At least eight strains of the coronavirus are making their way around the globe, creating a trail of death and disease that scientists are tracking by their genetic footprints. While much is unknown, hidden in the virus’s unique microscopic fragments are clues to the origins of its original strain, how it behaves as it mutates and which strains are turning into conflagrations while others are dying out thanks to quarantine measures. Huddled in once bustling and now almost empty labs, researchers who oversaw dozens of projects are instead focused on one goal: tracking the current strains of the SARS-CoV-2 virus that cause the illness COVID-19.
Labs around the world are turning their sequencing machines, most about the size of a desktop printer, to the task of rapidly sequencing the genomes of virus samples taken from people sick with COVID-19. The information is uploaded to a website called NextStrain.org that shows how the virus is migrating and splitting into similar but new subtypes. While researchers caution they’re only seeing the tip of the iceberg, the tiny differences between the virus strains suggest shelter-in-place orders are working in some areas and that no one strain of the virus is more deadly than another. They also say it does not appear the strains will grow more lethal as they evolve.
“The virus mutates so slowly that the virus strains are fundamentally very similar to each other,” said Charles Chiu, a professor of medicine and infectious disease at the University of California, San Francisco School of Medicine. That makes it easy to spot new lineages as they evolve, said Chiu. “The outbreaks are trackable. We have the ability to do genomic sequencing almost in real-time to see what strains or lineages are circulating,” he said. So far, most cases on the U.S. West Coast are linked to a strain first identified in Washington state. It may have come from a man who had been in Wuhan, China, the virus’ epicenter, and returned home on Jan. 15. It is only three mutations away from the original Wuhan strain, according to work done early in the outbreak by Trevor Bedford, a computational biologist at Fred Hutch, a medical research center in Seattle.
On the East Coast there are several strains, including the one from Washington and others that appear to have made their way from China to Europe and then to New York and beyond, Chiu said. COVID-19 hits people differently, with some feeling only slightly under the weather for a day, others flat on their backs sick for two weeks and about 15% hospitalized. Currently, an estimated 1% of those infected die. The rate varies greatly by country and experts say it is likely tied to testing rates rather than actual mortality. Chiu says it appears unlikely the differences are related to people being infected with different strains of the virus. “The current virus strains are still fundamentally very similar to each other,” he said.
The COVID-19 virus does not mutate very fast. It does so eight to 10 times more slowly than the influenza virus, said Anderson, making its evolution rate similar to other coronaviruses such as Severe Acute Respiratory Syndrome (SARS) and Middle East Respiratory Syndrome (MERS). It’s also not expected to spontaneously evolve into a form more deadly than it already is to humans. The SARS-CoV-2 is so good at transmitting itself between human hosts, said Andersen, it is under no evolutionary pressure to evolve. –USA Today
Scientists in Iceland found 40 mutations of the coronavirus among people with the deadly bug in the country — and that seven infections came from people who attended the same soccer match in the UK, according to a report. The researchers discovered the mutations — or small changes in the genome of the virus — by analyzing swabs of COVID-19 patients in the country, where nearly 648 cases had been reported as of Tuesday afternoon, according to the Iceland outlet Information.
Health authorities, along with biopharmaceutical firm deCODE Genetics, tested 9,768 people, including those who had already been diagnosed, people with symptoms and high-risk populations. Some 5,000 people who did not show any symptoms agreed to participate — and 48 came back with positive results for the virus. The results ultimately helped deCODE Genetics determine how the rampant virus entered Iceland in the first place. –NY Post