By Cheryl Pellerin
DoD News, Defense Media Activity
FORT DETRICK, Md., Dec. 22, 2014 – At the U.S. Army Medical
Research Institute of Infectious Diseases here, scientists who develop and
refine diagnostics do more than work in a laboratory. Some take their
disease-identifying tools into the field and try them out on a virus’s home
turf.
That’s what virologist Dr. Randal J. Schoepp as doing in
Sierra Leone in 2006, working as part of a collaborative project to develop and
refine diagnostic tests for Lassa fever, a hemorrhagic virus endemic to Sierra
Leone, Liberia and Guinea.
Schoepp is chief of the Applied Diagnostics Department in
the Diagnostics Systems Division at USAMRIID. Since March 2014, he’s spent a
total of 12 weeks in West Africa, where he and colleagues support the U.S.
Ebola response.
“What’s better than to have an opportunity to take
diagnostics that we develop in the laboratory out and look at a real-world
situation?” he asked. “Because a lot of these things work just fine in the lab,
but … they might not work well with African serum or at 80 degrees.”
The Sierra Leone project, funded by the Armed Forces Health
Surveillance Center’s Global Emerging Infections Surveillance and Response
System, or GEIS, began looking for Lassa fever in patient samples but also
found many other viruses, including Ebola.
Undiagnosed Fever-causing Diseases
The research team found evidence of dengue fever, West Nile,
yellow fever, Rift Valley fever, chikungunya, Marburg and Ebola viruses in
patient samples collected in Sierra Leone, Liberia and Guinea between 2006 and
2008.
The Ebola finding was surprising in a region that had
reported only one case of Ebola, the Tai Forest strain, in Cote d’Ivoire in
1994. And the strain found in Sierra Leone turned out to be Zaire, the most
virulent Ebola strain and the one causing West Africa’s current outbreak.
In a research paper about the Ebola finding published in the
Centers for Disease Control and Prevention’s Emerging Infectious Diseases
journal in July, first author Schoepp said the research shows that Ebola had
been circulating in the region since 2006, nine years before the current
outbreak.
“We're trying not only to improve the [diagnostics] capacity
of a host country, but to understand what diseases we’ll find there,” he said.
Developing and Refining Diagnostic Tests
USAMRIID has been working in the region since 2006, when it
began the collaborative project to develop and refine diagnostic tests for the
Lassa fever virus. In addition to providing laboratory testing and training
support for the current Ebola outbreak, USAMRIID has provided more than 10,000
Ebola assays to support lab capability in Sierra Leone and Liberia.
In the USAMRIID Applied Diagnostics Department, Schoepp
said, he and his colleagues work primarily on immunodiagnostics development,
test and evaluation. Immunodiagnostics use antibodies to detect a virus or
virus products, or antibodies that result from infections with a virus.
In this work, he said, “we partner with a lot of the
overseas GEIS labs.”
Global Infectious Disease Surveillance
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 has a Ghana Detachment in Accra that is part of
the Noguchi Memorial Institute for Medical Research, with a laboratory and
administrative spaces where the detachment’s manager and technicians work.
“We work with the Ghana Detachment out of NAMRU-3,” Schoepp
said. “I have a colleague there from NAMRU-3 that has just been sent to the
Ghana Detachment because it's closer to Liberia, and NAMRU-3 wants to build
capabilities in Liberia.”
The Ghana Detachment was established to build a partnership
between the U.S. Navy and Ghana for lab- and field-based infectious disease
research and to perform clinical and field trials of new drugs and vaccines
against malaria, according to a State Department fact sheet.
In Ghana, research collaboration among NAMRU-3, the Ghana
Ministry of Health and the Noguchi Institute began in 1995 and recently was
formalized.
Infectious Disease Research Collaboration
Accomplishments there include creating a West African
military collaboration for disease surveillance for flu, sexually transmitted
infections and acute febrile, or fever-causing, illnesses. Upcoming efforts
include research collaborations with GEIS, one involving malaria resistance and
another involving immunology, or how the body protects itself from disease.
Another GEIS-funded lab is NAMRU-6, hosted by the Peruvian
Navy and collocated at their hospital in Lima. This lab conducts research and
surveillance on infectious diseases that threaten military operations in the
region, including malaria, dengue fever and yellow fever.
“We do a lot of work with USAMRU-K in Nairobi,” Schoepp
said, referring to the U.S. Army Medical Research Unit-Kenya.
Twelve Army soldiers and two DoD civilians make up USAMRU-K.
Assigned to the unit are two U.S. Embassy staff members and more than 600
contracted Kenya Medical Research Institute or Henry Jackson Foundation-Medical
Research International employees.
Immunodiagnostics for Overseas Labs
USAMRU-K headquarters is in Nairobi, Kenya, on the campus of
the Kenya Medical Research Institute. Primary operational sites in Kenya
include Nairobi, Kericho Field Station and Kisumu Field Station.
“My program in GEIS is to help with and provide
immunodiagnostics to the overseas labs,” Schoepp said.
“I try to do this collaboratively,” he added. “I don't want
to be ‘Diagnostics R Us’ and just hand out diagnostics, because diagnostics
interpretation is as important as the test you're using. If you don't
understand the test, your interpretation can be completely wrong.”
The virologist said he also works with scientists in
Mongolia, “because one of the hemorrhagic fevers I have an interest in and the
DoD has an interest in is Crimean Congo hemorrhagic fever,” or CCHF.
Stalking a Tick-borne Virus
CCHF is a widespread hemorrhagic disease caused by a
tick-borne virus that causes severe outbreaks. Cases have a fatality rate of 10
percent to 40 percent. CCHF is endemic in Africa, the Balkans, the Middle East
and Asian countries south of the 50th parallel north, the geographical limit of
the main tick carrier, according to the World Health Organization.
“CCHF is a very plastic virus, meaning it has a lot of
variability among strains, and we don't even understand how plastic it is,”
Schoepp said. “We know what strains are in Russia but we have very little idea
what strains are in China, and Mongolia sits right between them.”
So Schoepp, in collaboration with a colleague, traveled to Mongolia,
got to know several scientists there and began working with them, he said.
Building Host Country Capacity
“We’re looking at over 2,000 human samples from five
different regions in Mongolia for antibodies to CCHF, and corresponding to that
we have ticks from livestock from the same villages where we're working with
the virology folks to attempt to isolate the virus out of those ticks and
identify it,” Schoepp explained.
The scientists are hoping to find CCHF, and they’ll also
look for any other tick-derived diseases that may be circulating in the
populations, he said.
These and other collaborations in the United States and
around the world allow USAMRIID to protect troops worldwide, respond to
international public health emergencies, identify undiagnosed febrile illnesses
that are circulating in host countries, build the country’s capacity to
identify diseases, and test their medical diagnostics in settings where
diseases naturally occur.
After spending 12 weeks in West Africa between since March,
Schoepp said, he wants to go back there to continue his search for undiagnosed
febrile diseases.
“I'm going to try to mimic in Liberia what we had in Sierra
Leone,” he said. “The infrastructure is better in Liberia, and we know bits and
pieces [about what infectious diseases are there], but nobody knows the whole
story. It's a chance for me to go in and tell another story.”
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