VOA常速英语:Ebola Vaccine Trials Underway in West Africa

Ebola has claimed the lives of more than 10,000 people in West Africa. Since last summer, researchers have rushed to get anti-Ebola vaccines into clinical trials. While it's too early to say that any of the potential vaccines work, some scientists say they are seeing strong results from some of the studies.

It's ironic...just as the Ebola epidemic in West Africa seems to be waning, clinical trials of potential vaccines are underway there.

A vaccine candidate is currently being tested in Guinea, where the Ebola virus is still active. Those likely to get the vaccine are medical workers and people who have been exposed to the virus.

Liberia has so few new Ebola cases that a clinical vaccine trial started there may be continued in Sierra Leone or Guinea.

At Emory University in the U.S., an investigational vaccine was given to an American doctor who may have been exposed to the virus at an Ebola treatment unit in Sierra Leone. Dr. Mark Mulligan reported the effects of the vaccine in the Journal of the American Medical Association.

“We saw strong responses from the innate immune system, the immediate responses, the first defenders in our body, and also from the subsequent antibodies and T cells that we want a vaccine to produce," said Mulligan.

The patient did not develop the Ebola virus, and he may not have been infected, but the immune response is what doctors hoped to see.

Dr. Thomas Geisbert was one of the researchers who developed this potential vaccine. Despite reports that researchers are closing in on an effective vaccine, he says there's still a lot of work to do.

"A lot of these different vaccines and treatments were developed against one species of Ebola, and a particular strain of that species, so there are five different species of Ebola virus. Three of those cause disease and morbidity, mortality in man," said Geisbert.

Dr. Geisbert says a vaccine that might work against the Zaire Ebola virus, the species circulating in west Africa, might not work against against another type of deadly Ebola virus.

But, if the vaccines are proven to work, Dr. Jesse Goodman says they could still be used in West Africa.

"It could benefit people if this outbreak went the wrong way again. And, even more importantly, these could be incredibly important tools for future outbreaks," said Goodman.

The results of the vaccine trial in Guinea could be available in July.