(Adds comments from CDC, details of tests)
NEW YORK May 28 U.S. health officials on
Wednesday walked back their earlier conclusion that a healthcare
worker who traveled from Saudi Arabia to Indiana and was
diagnosed with Middle East Respiratory Virus (MERS) had infected
an acquaintance upon his return.
The U.S. Centers for Disease Control and Prevention said in
a statement that additional and more definitive laboratory tests
showed that the healthcare worker did not spread the deadly
virus to an Illinois business associate he met with twice before
becoming ill and seeking treatment at a hospital.
The case in Illinois had been considered the first direct
transmission of the MERS virus on U.S. soil. It raised alarms
that it might be transmissible outside hospitals and other
healthcare settings, especially by doctors, nurses and others
who had worked in Saudi Arabia, the epicenter of MERS.
CDC and state and local public health officials are
conducting voluntary tests on people who had contact with the
Indiana patient and the second U.S. MERS patient, a man in
Florida, who had also returned from Saudi Arabia.
Earlier this month the Illinois man tested negative for MERS
in a method that uses respiratory samples and can quickly
indicate if a person has an active viral infection. But he
tested positive on two blood tests that are considered more
Those initial blood-test results "indicated the possibility"
the Illinois resident was infected with MERS, Dr David Swerdlow,
who is leading CDC's MERS response, said in a statement.
"This compelled us to notify and test those people with whom
he had close contact in the days following his interaction with
the Indiana MERS patient."
The blood tests included one that takes several days to
yield a result, which was that the Illinois resident was not
infected with MERS.
"While we never want to cause undue concern among those who
have had contact with a MERS patient, it is our job to move
quickly when there is a potential public health threat," said
Swerdlow. "Because there is still much we don't know about this
virus, we will continue to err on the side of caution when
responding to and investigating cases of MERS in this country."
The new analysis means that no MERS infections have been
found in any of the contacts of the two MERS patients in the
Since it was first identified in 2012, MERS has infected at
least 536 people, according to the World Health Organization,
and killed 145. It causes fever, body aches, cough and sometimes
How MERS is transmitted from person to person is not well
understood, but most cases have occurred through close physical
contact with an infected person or animal, such as a camel,
which is thought to be a reservoir for the virus.
(Reporting by Sharon Begley; Editing by Chizu Nomiyama)