Guinea has officially declared that it is dealing with an Ebola epidemic after the deaths of at least three people from the virus.

Iran Press/Africa: The victims and four others fell ill with diarrhea, vomiting, and bleeding after attending the burial of a nurse.

Between 2013 and 2016 more than 11,000 people died in the West Africa Ebola epidemic, which began in Guinea.

In response to that epidemic, which mainly affected Guinea and its neighbors Liberia and Sierra Leone, several vaccines were trialed, which have since been successfully used to fight outbreaks in the Democratic Republic of Congo.

"The WHO is on full alert and is in contact with the manufacturer [of a vaccine] to ensure the necessary doses are made available as quickly as possible to help fight back," the AFP news agency quotes Alfred George Ki-Zerbo, the WHO representative in Guinea, as saying.

A nurse who worked a health center in Goueké, near the south-eastern city of Nzérékoré, died on 28 January and her funeral was held four days later.

Community funerals, where people help wash the body of the person who has died, can be a key way of spreading Ebola in the earlier stages of an outbreak.

The bodies of victims are particularly toxic. The incubation period can last from two days to three weeks.

Ebola jumps to humans from infected animals, such as chimpanzees, fruit bats, and forest antelope. Bushmeat - non-domesticated forest animals hunted for human consumption - is thought to be the natural reservoir of the Ebola virus.

It then spreads between humans by direct contact with infected blood, bodily fluids, or organs, or indirectly through contact with contaminated environments.

All those infected at the funeral of the nurse were over the age of 25, health officials say.

Following a crisis meeting on Sunday, the health ministry said all cases had been isolated, contact tracing was ongoing and a treatment center was to be set up in Goueké.

Experts say containment is key to fighting the disease. During the 2015 trial in Guinea - 100 patients were identified and then close contacts were either vaccinated immediately or three weeks later. In the 2014 close contacts who were vaccinated immediately, there were no subsequent cases of Ebola.