By Cheryl Pellerin
American Forces Press Service
WASHINGTON, May 12, 2014 – A Defense Department-funded lab
in Egypt detected the earliest-known cases of Middle East Respiratory Syndrome
virus, a new coronavirus strain that is infecting people on the Arabian
Peninsula, an expert from DOD’s global disease surveillance system said.
The lab shared samples so the Centers for Disease Control
and Prevention could develop tests for the virus, said Public Health Service
Capt. Michael J. Cooper, head of respiratory disease for the Global Emerging
Infections Surveillance and Response System, called GEIS, which is part of the
Armed Forces Health Surveillance Center.
GEIS is a funding agency that supports military laboratories
in the United States and in Egypt, Germany, Kenya, Peru, Thailand and Singapore
-- all of which serve as hubs for infectious disease surveillance and as
regional hubs for addressing global public health issues -- and it funds
respiratory disease surveillance projects at 400 sites in more than 30
countries.
As of May 9, the World Health Organization, or WHO, reports
536 laboratory-confirmed cases of MERS-CoV since April 2012,including 145
deaths.
Some people infected with MERS-CoV develop severe acute
respiratory illness with symptoms of fever, cough and shortness of breath, and
about 30 percent of known cases die, according to the CDC. Some people exposed
to the virus get only a mild respiratory illness, the CDC reported.
A CDC fact sheet says MERS-CoV has spread between people in
close contact and from infected patients to health care workers. Clusters of
cases in several countries are being investigated, as is the source of the new
strain, the CDC says.
MERS-CoV has been found in camels in Qatar, Egypt and Saudi
Arabia, and in a bat in Saudi Arabia. Camels in other countries have tested
positive for MERS-CoV antibodies, meaning they have been infected with MERS-CoV
or a closely related virus. But CDC says it needs more information to identify
the potential roles of camels, bats or other animals in MERS-CoV transmission.
On May 2, CDC reported the first confirmed U.S. case of
MERS-CoV in a health care worker traveling from Saudi Arabia to London to the
United States. The patient was hospitalized in Indiana and at the time was in
stable condition, CDC officials said.
During a recent interview with American Forces Press Service,
Cooper said, “[GEIS’s] first objective is force health protection” for U.S.
troops, “but we are also involved with global public health issues.”
He added, “We also do surveillance on diseases that aren't
necessarily militarily relevant but are relevant to global public health
because sick people can board aircraft and carry infectious diseases anywhere
in the world within 24 hours.”
One of GEIS’s funded laboratories is the Naval Medical
Research Unit-3, or NAMRU-3, the largest DOD overseas lab, formally established
in Cairo in 1946.
Scientists there conduct research on a range of diseases and
perform infectious disease surveillance to support military personnel deployed
to Africa, the Middle East and Southwest Asia.
NAMRU-3 also works closely with the Egyptian Ministry of
Health and Population, the U.S. National Institutes of Health, WHO and CDC, and
is a WHO regional Collaborating Center for HIV and Emerging Infectious
Diseases.
Cooper said GEIS funds the Jordan National Influenza Center,
called the NIC, and that NAMRU-3 and members of the Jordan Ministry of Health
and the NIC work together often.
The story of MERS-CoV, although the first case reported to
WHO was from Saudi Arabia in September 2012, really began in Jordan earlier
that year, Cooper explained.
“In April 2012 there was an outbreak of severe acute
respiratory illness in a Jordanian hospital -- we call them SARI cases -- and
the folks at the Ministry of Health in Jordan asked NAMRU-3 to help with the
outbreak investigation,” he said.
Eleven people were hospitalized, he said. Eight of them were
health care workers. NAMRU-3 team members arrived and took samples from the
patients, but back at the lab in Cairo they could find no pathogen at that
time, he said. MERS-CoV hadn’t yet been discovered, so no specific test for it
existed.
On April 24, the NAMRU-3 team told the Jordan Ministry of
Health that all samples tested negative for known coronaviruses and other
respiratory viruses. The samples were saved at NAMRU-3.
“Flash forward to September 2012, London, England,” Cooper
said.
On Sept. 11 that year, a 49-year-old Qatari man with a
history of travel to Saudi Arabia was flown by air ambulance from Qatar to a
London intensive-care unit. He suffered from acute respiratory infection and
kidney failure.
Eleven days later, on Sept. 22, the U.K. Health Protection
Agency reported to WHO that it had compared information from the U.K. Qatari
patient with that of a virus sequenced earlier in the year by Erasmus
University Medical Centre in the Netherlands. This earlier sample, from lung
tissue of a 60-year-old Saudi man who had died in June, was a 99.5 percent
match with the new coronavirus strain from the Qatari man, according to a Sept.
23 WHO Global Alert and Response document.
Now, WHO had two confirmed cases of the new strain.
The news “caused a lot of concern,” Cooper said, “because
the last time the world saw an emerging coronavirus strain was 2002-2003, and
it was severe acute respiratory syndrome -- SARS -- which caused about 8,000
cases and 780 deaths” in more than 24 countries.
In 2012, Cooper said, this got GEIS’s attention.
“In October we decided to ask our partners at four different
locations to do retrospective surveillance for all their samples that were
associated with respiratory illness,” he said.
The partners were NAMRU-3 in Cairo, Landstuhl Regional
Medical Center in Germany, U.S. Army Research Unit-Kenya in Africa and the U.S.
Air Force School of Aerospace Medicine at Wright Patterson Air Force Base in
Ohio.
“Then NAMRU-3, remembering the outbreak in Jordan in April,”
Cooper said, retested the Jordan samples from April. By November 2012 the
NAMRU-3 team provided lab results that confirmed two of the original 11 cases
as infections by the novel coronavirus.
“Now the NAMRU-3 team understood that what they had back in
April 2012 was the earliest known outbreak of this emerging infection,” Cooper
explained.
“Until then,” he said, “the vast majority of cases had come
out of Saudi Arabia. If we had never found the earliest cases, Jordan wouldn't
even be in the mix. And you’d like to know the earliest cases to get an idea of
where [the new strain] is coming from.”
NAMRU-3 then shared samples from the earliest MERS-CoV cases
with CDC, Cooper said, “so an assay, or test, could be developed, which is very
important. Now you've got a positive control [for the novel MERS-CoV strain]
because you have the actual sample.”
According to its fact sheet, with such samples CDC develops
molecular diagnostics that let scientists accurately identify MERS cases, and
it develops assays to detect MERS-CoV antibodies. These lab tests help
scientists tell whether a person is or has been infected with MERS-CoV.
CDC also provides MERS-CoV test kits to state health
departments so they can test for patients under investigation for MERS-CoV
infection.
CDC evaluates genetic sequences as they become available as
well, and at NAMRU-3 scientists today grow the new coronavirus strain, sequence
it and continue to work with it.
“They’ve gotten additional samples to confirm because they
serve as a WHO reference laboratory for that region,” Cooper said, “and they've
recently discovered a travel case from the Saudi Arabian peninsula to Egypt.”
NAMRU-3 also trains physicians and scientists from
ministries of health in countries such as the United Arab Emirates, Saudi
Arabia, Jordan and Yemen, and in West African countries, he said, adding that
the GEIS-funded training involves teaching attendees how to use the MERS-CoV
assays and discussing important facts about the new coronavirus.
Cooper defines infectious disease surveillance as “basically
collecting data in a systematic way so that disease levels can be monitored.
Hopefully this information gives you an idea of the distribution of a given
disease and hopefully helps to understand what populations are affected.”
Doing surveillance, he said, usually involves “testing
people who are ill and in some cases testing people who are not ill but who may
have been exposed to the virus.”
All DOD major infectious disease labs have surveillance
capabilities for MERS-CoV, Cooper added, and all DOD major medical centers
around the world have MERS-CoV diagnostic capabilities.
GEIS does surveillance for a range of diseases, he said,
including H7N9 influenza emerging in China, enteric infections like those
caused by contaminated food or water, parasitic infections like malaria, other
respiratory infections like multidrug-resistant tuberculosis, and sexually
transmitted infections.
Cooper said respiratory diseases are the ones that typically
go pandemic because of the way they spread.
“The most recent examples are SARS and the pandemic of 2009,
which was H1N1 influenza,” he said. “They spread easily from person to person
and they don’t kill their hosts too soon or maybe at all.”
About MERS-CoV, Cooper said, “We were well ahead of the
curve on this one and we have a very strong network of respiratory disease
surveillance.”
He added, “We'll also say this, though. We’re dealing with a
virus and viruses can change and quite frankly frequently do change. So you
have to monitor the situation and you have to be careful. Surveillance is key
in this situation. You have to know what's going on.”
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