◎ Science and Technology Daily intern reporter Zhang Jiaxin
According to the journal Nature Communications, researchers have detected the "mysterious lineage" of the new coronavirus in the sewage of the sewers of New York, USA - fragments of the virus with new mutation patterns.
Researchers have detected the virus in New York City in January 2021, and over the past year, it has "continued to appear in sewage in New York City." Since mid-2020, researchers at the University of California, Berkeley, have continued to find similar "mysterious lineages" in wastewater from multiple sewers in the San Francisco Bay Area (and possibly further afield in California). Similar findings have been made in other U.S. cities, but have not yet been published. This has raised new concerns about whether the coronavirus is escaping immunity.
Researchers at the University of California, Berkeley, are removing a wastewater autosampler from a sewer. Image credit: Erin Easy/University of California, Berkeley
There is no evidence yet of evidence of how long the virus has been circulating, but the study notes that many of the viruses in the spectrum share a large number of mutations with the new coronavirus variant, Theomecron.
Curiously, the virus is only present in human excrement, not in the human body. Scientists at the University of California, Berkeley, say it shows no signs of triggering illness or leading to a new outbreak.
The researchers themselves disagree on the origins of these lineages. Some tend to think that the virus came from those infected with the virus whose infections were not sequenced and caught; others suspect that the virus of this "lineage" may have come from animals infected with the new crown, possibly the city's vast population of mice.
The source of the virus is still unknown
But "native" in the United States
According to The New York Times, researchers have been sampling wastewater from 14 sewage treatment plants in New York City since June 2020. In January 2021, they began targeted sequencing of the samples, focusing on some of the genes of the virus's most important spike protein.
The Researchers examined 5,000 other wastewater samples from around the world and found this "lineage" in only 7 samples, all from New York State, according to the Life Sciences Network. Whatever the virus is, they are "native" to the United States.
Scientists have yet to figure out where the "lineage" of these viruses comes from. They believe that these "mysterious lineages" of viruses may come from infected people who have not been detected or have not yet been tested. But the researchers say such a theory is unlikely given the fact that New Yorkers, as well as people who may carry certain variants, tend to move across the city unrestrictedly, with the virus constantly showing up at the same sewage treatment plants.
The researchers found that fragments of the virus with new mutation patterns recur in a handful of processing plants. They said they could not disclose specific factories or regions.
So far, these variants have not been found in clinical patients in New York. Nonetheless, Dr John Danney, a virologist at Queen's College at the University of Cambridge in the United Kingdom, speculated that the viruses may have come from people who were confined to medical facilities in a small number of areas of the city. But he has been unable to prove it.
Danei said we were able to locate its source in a small area of the sewage sheds of some hospitals. He emailed doctors and hospitals in those areas, but never received a response.
The mysterious virus has the same mutation as TheOmilon
The researchers used a viral genome sequencing technique, but this sequencing focused on only about half of the spike proteins needed for the virus to enter the cell, containing the receptor-binding domain (RBD). Many mutations that allow Omikejong to evade vaccine antibodies or non-Omiljun infections are present in RBD. The same is true of viral mutations in the "lineage" found in New York City wastewater. The researchers used the term "lineage" to avoid confusion with the term "variant of concern" used by the World Health Organization.
Interestingly, this mysterious virus has some of the same mutations as Omi kerong, or mutations that occur in the same location. Experiments have shown that these viruses may also evade certain antibodies.
Electron microscopy images of the coronavirus. Image credit: Rocky Mountain Laboratory (NIAID-RML)
The team studied four of these mysterious lineages, named WNY1, WNY2, WNY3, and WNY4. They found that all of these viruses have the ability to partially or completely evade antibodies that easily neutralize the original strain of the virus. Although the plasma of a vaccinated person or person who has previously been infected with the virus can be partially and in all 4 lineages, the neutralizing effect is reduced compared to the original virus strain.
The researchers speculate that the coronavirus discovered in New York City may be the result of the same selective pressures that mutate to evade certain body's immune defenses.
"Mystical lineage" originated in animals?
Still not determined
Another possibility is that the carriers of these mysterious "lineages" are not humans. Rats in New York City's sewers may be one of the targets.
But the researchers could not find conclusive evidence linking mice to the virus. The team sequenced animal genes in the wastewater, primarily to find out which species in addition to humans left excrement in the sewers. In addition to genes from animals (cows, pigs, chickens) that people eat, the researchers also found evidence of cat, dog, and mouse genetic material in sewers. But none of them are highly popular. And the sewage treatment plant with the highest proportion of mysterious coronaviruses has the lowest proportion of rat genes — and sometimes, mouse genes are not even detected.
Since last summer, researchers have been working with the U.S. Department of Agriculture's Bureau of Animal and Plant Health To look for signs of the virus from blood and fecal samples from local mice. So far, they have found nothing.
Maybe rats aren't the source of the mysterious lineage. Scientists have repeatedly found that humans can transmit the virus to animals, especially pets, zoo animals, mink and other animals. This has raised concerns that the virus may "make its home" in animal hosts, mutate there, and then be transmitted back to humans.
Often, rats are not the most worrisome problem, nor is there any evidence that the virus spreads in wild mice. The way humans infect mice is also unknown.
But scientists say there is still a possibility of some sort of animal origin.
Source: Science and Technology Daily
Editor: Zhang Shuang
Review: Julie
Final Judgement: Wang Yu