Uganda to conduct Marburg and Ebola vaccine trials

Published 15 October 2009

Ebola and Marburg are viral infections that have a high mortality, killing 90 percent of victims; no effective treatment exists for these highly infectious diseases, which cause extensive internal bleeding and rapid death

Uganda could hold the key to the Ebola and Marburg vaccines as the country has been selected for a high profile second stage safety trial in humans. Dr. Hannah Kibuuka, the director clinical programs at the Makerere University Walter Reed project, who is conducting the experiments, said the trial comes after a smaller one in the United States.

Irene Nabusoba writes that in an interview with the New Vision on Tuesday, Kibuuka said they hope to administer the vaccine next week.  The exercise will kick off a research process that is expected to last two years. “They are artificially made DNA vaccines. They do not contain any Ebola or Marburg virus particles,” Kibuuka explained. “The DNA instructs the body to make one type of protein that is similar to the surface protein of the virus, triggering an immune response when the virus attacks because the body recognizes it as foreign.”

Ebola and Marburg are viral infections that have a high mortality, killing 90 percent of victims. No effective treatment exists for these highly infectious diseases, which cause extensive internal bleeding and rapid death.

Experts say vaccination is the best strategy for preventing the deadly infections classified by the U.S. Centers for Disease Control and Prevention (CDC) as category A of bioterrorism agents. “The viruses are associated with bio-terrorism because they are highly infectious, easily transmissible, cause public panic and social distress. It is important that we develop a vaccine,” Kibuuka noted.

She said Uganda is the only country participating in the second trial (phase1B). Phase 1A trial by the US vaccine research center involved 20 people.

Phase1A involves between 20-50 people and is aimed at assessing the safety of the vaccine. It is followed up for one year to assess the immune responses generated. “Ours is an expansion of the first one involving 108 people. We administer the vaccines to healthy individuals aged 18-50 years because we are assessing safety,” Kibuuka explained. “We shall first give the Ebola and Marburg vaccines to different individuals then get another group to give both jabs (vaccines) to see how they respond.”

Scientists first try vaccines in rats, bats, or primates like monkeys, chimpanzees and baboons before involving humans.

Unlike HIV trials, volunteers will not be exposed to the Ebola/Marburg virus.
The trial will be parallel to one where primates are exposed to the virus to ascertain its effectiveness in preventing the infections.

We are just testing how the body reacts. When proven successful, the vaccine will be given to health workers, tourists, military officers and people exposed like cave workers or those in affected areas because these infections are rare and you can never predict when they break out,” Kibuuka said.