The SARS, or severe acute respiratory syndrome, epidemic in 2003 started in China and infected more than 8,000
people, including one person in Chapel Hill, and killed nearly 800 people overall. Most of the
people who died were over 60 years old. In 2004, SARS disappeared from humans,
and many groups thought the virus was extinct.
“It really isn’t extinct,” Baric said. “It’s really
circulating through bats.”
Though how the virus in bats is transmitted to humans is
unknown, Baric said he thinks it could be transmitted through contact with bat saliva
“With globalization, we have more and more areas that have
never really seen people before but now there’s development,” said Vineet Menachery,
a postdoctoral scholar working with Baric. “These bats don’t just go away — they can be found in buildings. So humans are getting into more contact with
Since the new sequence is 12 percent different from the
original SARS virus, the current treatment for the SARS virus does not work on
the new variant.
“It’s not just one virus in the reservoir, it’s this pool.
Imagine this pool of closely related but different viruses, and each time one
comes out of the pool, it’s like having a pool full of fish and a fish jumps
out,” Baric said. “Trying to make vaccines for that pool becomes really
difficult because you don’t know the boundaries of what you need to target.”
Virologist Mark Heise, who works with the team, said the
virus is more complicated than he originally thought in 2004.
“When we first started working on SARS in 2004, we knew
almost nothing about it,” he said. “We were afraid that if we used the wrong
sources in the vaccine we would make the disease worse. Since then we have
developed a much stronger picture.”
Helen Lazear, a microbiology and immunology assistant professor who studies diseases in bats, said researchers do not yet know why bats can harbor the number of diseases they do.
“We’re really in the early stages of learning about the
epidemiology of bats,” she said. “There is a growing interest in bats and
because of the growing interest, more people go out and look for viruses. The
more they look, the more they find.”
Though many questions are left unanswered, Baric plans to
continue his research to take a proactive approach to preventing future
“One of the major implications of our study is it now
positions us to make better vaccines and have drugs that are much better and
broader in their activities," he said. "So, if and when a future outbreak occurs, we will be
in a position to move rapidly with intervention strategies."