Coronavirus a product of evolution, may have been in humans for years: Study
As the coronavirus pandemic continues to evolve,
infecting millions worldwide, a team of scientists has discovered that Covid-19 could have spread among humans for years
or even decades before now.
According to findings published in the journal Nature
Medicine, the virus could have possibly been transmitted from animals to humans
much before it was first detected in Wuhan province of China. In fact, there
are speculations that it could have been as long as a decade.
The study, which was conducted by an international team
of scientists from Australia, Britain and the US, was released on March 17 in the scientific journal.
“Then, as a result of gradual evolutionary changes over
years or perhaps decades. The virus eventually gained the ability to spread
from human to human and cause serious, often life-threatening disease,” Dr
Francis Collins, director of the US National Institute of Health, said in an
article published on the institute’s website.
The study was conducted by Kristian Andersen from the
Scripps Research Institute in California, Andrew Rambaut from the University of
Edinburgh in Scotland, Ian Lipkin from Columbia University in New York, Edward
Holmes from the University of Sydney, and Robert Garry from Tulane University
in New Orleans.
“By comparing the available genome sequence data for known
coronavirus strains, we can firmly determine that SARS-CoV-2 originated through natural processes,”
said the lead researcher Kristian Andersen.
Besides them, Italian professor Giuseppe Remuzzi had
pointed at “strange pneumonias” in Italy since last November. This could mean
that Covid-19, which proved to be equally fatal in the country, could
have reached Europe before anyone knew about it.
Prof Remuzzi, director of the Mario Negri Institute for
Pharmacological Research in Milan, said he would not be surprised if some
asymptomatic carriers had travelled around China or even abroad before December
The unusual cases of pneumonia in November and December
could mean that virus was already spreading in Lombardy, Italy’s worst-hit
region, before Wuhan made headlines, he said.
Speaking on similar lines, a Chinese doctor working, who
is treating Covid-19 patients in Beijing, said numerous cases of mysterious
pneumonia outbreaks had been reported by health professionals across several
countries last year.
“There will be a day when the whole thing comes to
light,” the doctor said, preferring anonymity.
Doctors in Wuhan also noticed a surge in the number of
pneumonia cases in December. Tests for flu and other pathogens returned
Shortly after the epidemic erupted, Chinese scientists
sequenced the genome of SARS-CoV-2 and made the data available to researchers
worldwide. The resulting genomic sequence data showed that Chinese authorities
had promptly detected the epidemic and that the number of cases were rising
because of human to human transmission after a single introduction into the
While an unknown strain was isolated, a team from the
Wuhan Institute of Virology led by Shi Zhengli traced its origin to a bat virus
found in a mountain cave close to the China-Myanmar border.
The virus has now infected every corner of the globe.