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 The problems reflect growing caution by regulators and transport
companies about handling Ebola as well as the limited resources of
West African countries which are struggling to help thousands of
infected citizens.
Ten scientists from eight major research institutions contacted by
Reuters reported they were unable to get Ebola samples in recent
months.
Tulane University, one of the institutions, received samples this
week, and the U.S. Centers for Disease Control and Prevention (CDC)
said it has reached an agreement to get live specimens, but it is
not clear if new supplies will satisfy demand, and transport remains
challenging.
Ebola mutates as it spreads, and while few expect it to acquire the
ability to transmit through air, for instance, scientists require a
constant supply of fresh samples to track these changes. The samples
hold up is not likely to delay the development of experimental
treatments. But if the virus undergoes significant changes that go
undetected, the drugs and tests might not work, researchers said.
Microbiologist and infectious disease expert Dr. Charles Chiu of the
University of California, San Francisco, needs samples from Ebola
patients to develop a new genetic test that could detect the disease
in infected individuals before symptoms appear.
"No one really knows right now what has the virus mutated to or if
it has mutated," he said. Without that research, “we're not going to
be able to determine in advance whether or not it has changed to a
form where it might evade diagnostic assays or might render current
vaccines or drugs ineffective."
Scientists say Liberia, Guinea and Sierra Leone have been slow to
release samples as they fight to contain the worst Ebola outbreak on
record which has killed about 5,000 people.
Laurie Garrett, the senior fellow for global health at the Council
on Foreign Relations in New York, said the issue is largely, and
appropriately, about safe transport, especially in the wake of the
recent mishandling of pathogens such as anthrax at U.S. government
laboratories.
"All the companies working on vaccines, diagnostics and treatments
are complaining about lack of access to viral samples," of Ebola,
she said.
KEY RESEARCH
Erica Ollmann Saphire of the Scripps Research Institute in La Jolla,
California, directs scientists working on Ebola treatments, such as
the three-antibody cocktail ZMapp, made by privately-held Mapp
Biopharmaceutical. She said in an e-mail she needs special cells
from Ebola survivors but has not been able to get any.
Dr. James Crowe, director of the Vaccine Center at Vanderbilt
University, is collaborating with Mapp on ZMapp, and has had
problems as well. Crowe said he may soon get some samples from U.S.
Ebola survivors through Emory University, after going to great
lengths to get them.
Crowe said a mutation in a key area of the virus “could compromise
the utility of the drug,” adding that there is no evidence that such
changes have occurred. Mapp did not respond to a request for
comment.
Importing Ebola virus into the United States has always been tricky,
said Dr. John Schieffelin of Tulane, who has treated Ebola patients
in Sierra Leone.
It has become even more difficult since the case of Thomas Duncan,
the first person diagnosed with Ebola in the United States, stoked
fears that the country could see its own outbreak. Duncan died in a
Dallas hospital on Oct. 8.
"You can divide the outbreak into pre-Dallas and post-Dallas,"
Schieffelin said. "Everybody has safety as a very, very high
priority, which is great. But sometimes the fear and hysteria trumps
science."
A RARE SUCCESS
This week, Tulane received a shipment of as many as 900 blood
samples from Ebola patients in Sierra Leone, capping several weeks
of effort. Tulane microbiologist Robert Garry believes the
university’s decade-long relationship with the Sierra Leone Ministry
of Health and Sanitation was key to getting that access.
Even so, exporting the samples from Sierra Leone required approval
from an ethics committee, the minister of health and the president.
On the U.S. side, importing samples of Ebola required a permit from
the CDC and passage through U.S. customs.
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The researchers switched shipping companies after one refused to
carry Ebola, missed a flight which did not have room for cargo, and
had to bring dry ice to Africa to pack the samples, which were
killed with a double shot of an inactivating agent, plus a shot of
ethanol for good measure.
Tulane researchers will extract RNA from the samples and ship them
to collaborators at Harvard University and the Broad Institute,
which plan to sequence the genetic code of the virus and track the
mutations taking place.
Earlier this year, Garry and several dozen colleagues from Harvard
and Sierra Leone found that Ebola was mutating twice as fast in
humans as in fruit bats which carried the virus. Their last sample
was from June, and it is not clear what changes have occurred in the
virus since then.
"You need to know how much of an adaptation the virus is making in
people," if you want to treat and diagnose it, Garry said.
CDC spokesman Tom Skinner said that the agency has struck agreements
with the three affected countries in West Africa and hopes to
acquire live specimens in a matter of weeks. It then would try to
share samples with other institutions.
"How much sharing will go on will depend on how many specimens we
receive and finalizing details around getting permission to share
from the affected countries," he said.
THE SCRAMBLE
The lack of access to African samples has also caused a scramble for
blood samples from the handful of U.S. patients who have survived,
including Dallas nurse Nina Pham who treated Duncan, said Thomas
Geisbert, a microbiologist at the University of Texas Medical
Branch.
Geisbert has a $26 million grant from the National Institutes of
Health to study experimental Ebola treatments. He works with leading
Ebola drug developers Profectus BioSciences and Tekmira
Pharmaceuticals Corp and is collaborating with Crowe at Vanderbilt
for a next-generation antibody treatment for Mapp.
Tekmira did not respond to a request for comment. Profectus Chief
Scientific Officer John Eldridge said the company had not
encountered problems, but added that Geisbert should have a better
understanding of the difficulties.
Geisbert does not think the delays in obtaining samples have held up
the development of specific products. Most of these are based on
samples from earlier Ebola outbreaks. But to confirm their
effectiveness, it would be helpful to test Tekmira's TKM-Ebola and
Mapp's ZMapp against the latest outbreak strains.
"There is no substitute for confirming activity against a live
infectious virus," he said.
Geisbert managed to get blood samples gathered in March from Ebola
survivors infected in Guinea, where the current outbreak started,
but has none from Liberia or Sierra Leone. He has made several
appeals to U.S. Ebola survivors and the hospitals that treated them,
and enlisted Tekmira, but has not succeeded.
"It's crazy. You ask, and nobody responds," said Geisbert, who asked
Reuters how to get in touch with Pham.
(Additional reporting by Sharon Begley in New York; Editing by
Michele Gershberg and Peter Henderson)
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