Download Research community stepping up efforts to learn about Ebola virus

Research community stepping up
efforts to learn about Ebola virus
by Dr. David L. (“Woody”) Woodland
(as published in the Summit Daily News of December 21, 2014)
In addition to serving as Chief Scientific Officer for Keystone Symposia, I am also the Editor-InChief of the international journal Viral Immunology that is published 10 times a year by Mary
Ann Liebert publishers. The journal publishes current, cutting-edge studies from research
scientists all over the world. In addition, the journal occasionally publishes special issues
focusing on a specific topic. In this regard, last February I commissioned two prominent
scientists to guest-edit an issue on a class of viruses called Filoviruses, the most familiar of
which is Ebola. Eerily, just a month later, the Ebola outbreak in West Africa became
international news. The focus of the special issue was subsequently changed to address Ebola
virus disease exclusively.
Today, the Ebola outbreak in West Africa has resulted in over 13,000 cases and approximately
5,000 deaths. While the disease epicenter has been Guinea, Sierra Leone and Liberia, there
have been additional travel-related cases in Nigeria, Mali, Senegal, Spain and the United
States. The challenge of dealing with an Ebola outbreak in poor countries with minimal health
services has proven to be especially great. Success is hampered by the fact that there are no
approved vaccines or treatments for Ebola. The urgency of the situation in Africa has driven the
research community to significantly increase research efforts into understanding this deadly
disease and to accelerate the development of anti-Ebola drugs and vaccines.
The special Viral Immunology issue on Ebola is guest-edited by Drs. Jeffery Hogan (Department
of Infectious Diseases, University of Georgia) and Bill Dowling (Biodefense Research
Resources Section, National Institute for Allergy and Infectious Diseases) and reveals some
fascinating insights into the virus and its interaction with the human body. One article’s
particularly significant finding is that many individuals in West Africa showed evidence of having
already been exposed to Ebola prior to the 2014 outbreak. In fact, a report by Dr. Boisen and
colleagues suggest that as many as one in five individuals showed evidence of prior exposure
to the virus even though there had been no recent outbreaks in that region. This suggests that
the virus may have been lurking unrecognized in the human population for some time prior to
the major current outbreak. There had previously been evidence that individuals in some parts
of Central Africa show evidence of prior Ebola exposure, also in the range of about one in five
individuals in some areas. In both studies, the scientists analyzed blood samples for the
presence of antibodies specific for Ebola. Antibodies are proteins that are elicited during
infection which are able to specifically latch onto the Ebola virus and assist in its destruction.
After clearance of the virus, these antibodies persist in the blood for months or even years,
serving as a marker for past exposure to the virus.
How could the disease have gone undetected prior to the current outbreak? One possibility is
that infections may have escaped detection by health surveillance because they presented
symptoms (fever, vomiting, etc.) very similar to other diseases endemic in that part of the world
such as malaria. But this doesn’t explain why these earlier exposures didn’t cause a major
outbreak. Perhaps there was a milder form of the virus circulating that causes asymptomatic
infections. Alternatively, individuals may have been exposed to dead forms of the virus present
in droppings from infected wildlife, such as fruit bats (or perhaps even from consuming infected
bushmeat). This could provide sufficient exposure to the virus to elicit an antibody response, but
would not in itself cause disease. Regardless of the source, evidence for the presence of
preexisting immunity to Ebola raises the question whether these individuals are resistant to
subsequent Ebola virus infection or have a higher survival rate after infection. This still needs to
be determined. Another key question is what factors contributed to the sudden emergence of
the extremely virulent Ebola virus that is now causing so much suffering in West Africa.
Hopefully, further research will soon answer these questions.
Research into Ebola virus disease is extremely dangerous. Sadly, two of the authors of the
paper mentioned died of Ebola prior to publication. However, the hope is that their article, and
other articles published in the upcoming issue of Viral Immunology, will advance our
understanding of this dreadful disease and help terminate the Ebola outbreak in West Africa.
If you would like to learn more about Ebola and other viral diseases, you may be interested in
attending a community panel discussion at Colorado Mountain College in Breckenridge on
Tuesday, January 13 at 7:30 PM with several scientists from Keystone Symposia’s “Viral
Immunity” conference.
David L. “Woody” Woodland, Ph.D. is the Chief Scientific Officer of Silverthorne-based Keystone
Symposia on Molecular and Cellular Biology, a nonprofit dedicated to accelerating life science discovery
by convening internationally renowned research conferences in Summit County and worldwide. Woody
can be reached at 970-262-1230 ext. 131 or [email protected].
For more (Petri) Dish columns, visit www.keystonesymposia.org.