Archive Number: 20130907.1929762
Study reveals more signs of MERS-CoV in camels
More than 90 percent of camels in Egypt tested positive for MERS-CoV antibodies.
have found more evidence that many camels in the Middle East have been
exposed to the Middle East respiratory syndrome coronavirus (MERS-CoV)
or a close relative, increasing the suspicion that camels may have
spread the virus to humans.
In serologic tests on 110 dromedary
camels in Egypt, one test showed that 94 percent of them had antibodies
to MERS-CoV, and a 2nd test revealed antibodies in 98 percent, according
to a report in today's [5 Sep 2013] issue of Eurosurveillance [see item
2]. Tests of humans, water buffaloes, cows, and other domestic animals
in Egypt and Hong Kong showed no MERS-CoV antibodies.
antibody titres were very high" in both sets of tests, "suggesting that
the virus infecting these camels was MERS-CoV virus itself or a very
closely related virus," says the report by a team of Chinese, Egyptian,
and American scientists.
The team also found that the camel sera with high MERS-CoV antibody
levels did not cross-react with the SARS (severe acute respiratory
"Taken together, these data indicate that a
MERS-CoV or a highly related virus is endemic in dromedary camels
imported for slaughter in Egypt," they state. "These findings provide
independent confirmation of the results recently reported by Reusken et
al [the Dutch-German team], who found very high antibody titres to
MERS-CoV in dromedary camels."
Because the camels used in the
study had been brought to Egypt from Sudan and other African countries,
it is unclear where they originally acquired their infection, the report
says. Given the similar findings from camels in Oman and the Canary
Islands, "it is likely that this coronavirus is widespread in North and
East Africa and the Arabian Peninsula."
If future research
confirms that bats and dromedary camels harbor MERS-CoV, "we will have a
scenario of a virus reservoir in bats with a peridomestic animal such
as the camel as intermediate host, which may in fact be the immediate
source of human infection," the investigators say.
They add that
in some MERS-CoV index cases, the patients had a history of exposure to
camels. "Given that the MERS-like coronavirus in camels appears to be
ubiquitous, it remains to be explained why MERS in humans appears
relatively rare," they observe.