Three Red Cross volunteers were among the first Ebola deaths in Congo

Three volunteer aid workers from the Red Cross were among the first people to die in the Ebola outbreak in the Democratic Republic of Congo.

The three were believed to have been infected on March 27 while handling bodies, the International Federation of Red Cross and Red Crescent Societies (IFRC) said in Geneva on Saturday.

The volunteers had been responding to another humanitarian emergency before it was known that Ebola was spreading in the area.

"They are among the first known victims of the outbreak," the IFRC said in a statement. "These volunteers lost their lives while serving their communities with courage and humanity."

According to the federation, the three died on May 5, May 15 and May 16.

The first Ebola cases were only confirmed in laboratory tests on May 15.

Experts believe the outbreak had gone undetected for weeks. Clusters of unexplained deaths had already been under investigation before the virus was identified.

However, because the outbreak involves the rare Bundibugyo strain of Ebola, standard tests initially failed to confirm the pathogen.

On May 17, the World Health Organization declared the outbreak a public health emergency of international concern (PHEIC). The WHO considers the risk of infection within Congo to be "very high," "high" in the wider region, but "low" globally.

Unlike the coronavirus, Ebola is not transmitted through airborne droplets but through close contact with the bodily fluids of infected people.

Corpses can also carry a high viral load for days after death.

The World Health Organization said on Friday there are nearly 750 suspected cases and 177 suspected deaths in Congo linked to the outbreak, warning the number of infections is "rapidly" rising."