Two Ebola vaccines undergo trials, appear positive

Two Ebola vaccines are currently being tested.

Two vaccines developed for the Ebola virus have been well received during the phase-two trials. 

The trials were tested on 1,000 participants. They included a placebo and were held in a controlled environment.

Fatorma Bolay, director of the Liberian Institute from Biomedical Research, presented the findings at the Conference on Retroviruses and Opportunistic Infections in Boston. The trials started in Monrovia, Liberia, in February 2015. The trials were sponsored by the National Institute of Allergy and Infectious Diseased and conducted by a partnership between researchers from Liberia and U.S.

The study was originally meant to be phase-three, which would have included 28,000 volunteers. The trials were scaled back, however, as the occurrence of Ebola virus cases in West Africa diminished.

The first vaccine was the cAd3-EBOZ, which is developed by using a chimpanzee-derived cold virus. The other vaccine, rVSV-ZEBOV, uses the vesicular stomatitis to carry the Ebola material.

For the trial, 1,500 men and women over the age of 18 participated. The volunteers -- who had never had Ebola -- took the vaccine at Redemption Hospital in Monrovia between Feb. 2 and April 30 of 2015.