DEC 31, 2014 12:00 AM PST

Experimental Ebola Vaccine Found to Be Safe and Potent

WRITTEN BY: Judy O'Rourke
Study findings published in The Lancet

The year winds to an end with a couple of polar-opposite Ebola news items, one involving human error, the other, human ingenuity.

In the first instance, the Centers for Disease Control and Prevention (CDC) reports that CDC researchers investigating the virus in a secure laboratory erroneously permitted potentially lethal Ebola samples to be handled in a much less secure lab at the CDC, Atlanta. One technician in the less-secure lab who might have been exposed to the virus shows no symptoms and is being monitored for 21 days. (Read the blow-by-blow from The Washington Post, at wapo.st/1tisYgw)

The researchers were aiming to determine if strain of the virus that has rampaged through West Africa this year is more fatal than earlier strains. Some 7,573 people in Guinea, Liberia, and Sierra Leone, have died in the current outbreak, which as of December 24 accounted for nearly 20,000 cases.

The second story, from The Lancet, reveals that two experimental DNA vaccines to protect against Ebola virus (and the related Marburg virus) are safe and produce a comparable immune response in healthy Ugandan adults and those found in healthy US adults earlier in 2014. Outbreaks of these two viral infections have occurred intermittently since they were first detected in 1976 (Ebola) and 1967 (Marburg). Ebola has a case fatality rate as high as 90%, Marburg, 80%. Similar to the Ebola virus, Marburg is a filovirus, which spurs internal bleeding at several sites. People frequently die as a consequence of multiple organ failure. (There are no effective vaccines against either virus.)

"This is the first study to show comparable safety and immune response of an experimental Ebola vaccine in an African population", says lead author Julie Ledgerwood, DO, National Institutes of Allergy and Infectious Diseases (NIAID) National Institutes of Health, Bethesda, Md. "This is particularly encouraging because those at greatest risk of Ebola live primarily in Africa, and diminished vaccine protection in African populations has been seen for other diseases."

Scientists from the agency devised the DNA vaccines that code for Ebola virus proteins from the Zaire and Sudan strains and the Marburg virus protein. The 2014 Ebola epidemic in West Africa involves the Zaire strain. The vaccines harbor the blueprints for the proteins on the outer surface of the virus.

"These findings have already formed the basis of a more potent vaccine, delivered using a harmless chimpanzee cold virus, which is undergoing trials in the USA, UK, Mali, and Uganda in response to the ongoing Ebola virus outbreak," Ledgerwood says.

The Lancet article, titled "Safety and immunogenicity of Ebola virus and Marburg virus glycoprotein DNA vaccines assessed separately and concomitantly in healthy Ugandan adults: a phase 1b, randomised, double-blind, placebo-controlled clinical trial," is found here: http://bit.ly/1JSCqMx

Image: Created by CDC microbiologist Cynthia Goldsmith, this colorized transmission electron micrograph (TEM) revealed some of the ultrastructural morphology displayed by an Ebola virus virion. [Photo credit: Cynthia Goldsmith]
About the Author
  • Judy O'Rourke worked as a newspaper reporter before becoming chief editor of Clinical Lab Products magazine. As a freelance writer today, she is interested in finding the story behind the latest developments in medicine and science, and in learning what lies ahead.
You May Also Like
DEC 01, 2019
Genetics & Genomics
DEC 01, 2019
Engineering a Better Viral Delivery System for Gene Therapy
To send gene therapy to diseased cells, scientists have turned to adeno-associated viruses (AAVs) to act as a delivery system....
DEC 04, 2019
Neuroscience
DEC 04, 2019
Antibiotic Usage May Cause Parkinson's, Study Finds
A study from Helsinki University Hospital, Finland suggests that excessive usage of certain antibiotics may increase one’s risk of developing Parkins...
DEC 05, 2019
Drug Discovery & Development
DEC 05, 2019
New Injection that Treats Peanut Allergy
Peanut allergies affect between 1 and 3% of the US population. Associated with a heightened risk of severe anaphylactic reactions, oral immunotherapy is th...
DEC 18, 2019
Clinical & Molecular DX
DEC 18, 2019
Germs don't stand a chance with new AI-powered diagnostic platform
We are steadily losing our edge in the war against infectious bacteria. A huge surge in antibiotic resistance is threatening healthcare and agricultural in...
DEC 27, 2019
Microbiology
DEC 27, 2019
Using a Cancer Drug to Fight Antibiotic-Resistant Pathogens
It takes a long time for a drug to be approved for use in humans; repurposing existing drugs is one way to get around that hurdle....
FEB 09, 2020
Microbiology
FEB 09, 2020
Investigating the Links Between Viruses and Cancer
The Pan-Cancer Analysis of Whole Genomes (PCAWG) has brought over 1,300 scientists together to gain new insights into the genetics of cancer....
Loading Comments...