The two vaccines will first be tested on more than 20,000 front-line healthcare workers in the new year, the UN's health agency said.Separately, a senior Red Cross official said he was confident the epidemic could be contained within four to six months.An assistant director general at the WHO said in remarks reported by the BBC that a serum was also was being developed for use in Liberia. The serum is to be based on antibodies extracted from the blood of Ebola survivors.Ebola, according to WHO, is a communicable disease transmitted from wild infected animal such as chimpanzees, monkeys and pigs among others, to a human, who come in direct contact with their secretions like blood, urine, faeces, saliva, and so on.It also spreads from one affected person to other person, again through bodily secretions. According to the WHO, Ebola has claimed over 4,000 lives across the globe so far and it is feared that the toll will rise in the next two months, if timely measures are not taken.[poll id="1367"]