The World Health Organization has authorized the use of experimental drugs to fight Ebola, with the death toll topping 1,000 and a Spanish priest becoming the first European to succumb to the outbreak.

The declaration by the UN's health agency came after a US company that makes an experimental serum called ZMapp said it had sent all its available supplies to hard-hit West Africa.

In addition, the Public Health Agency of Canada said it will donate up to 1,000 doses of an experimental, Canadian-made vaccine to be used in response to the outbreak, The Globe and Mail reported in Toronto on Tuesday.

WHO assistant director general Marie-Paule Kieny said in Geneva after a meeting of medical experts, "In the special circumstances of this Ebola outbreak, it is ethical to offer unregistered interventions as potential treatments or prevention."

UN chief Ban Ki-moon announced plans to step up the global response to the outbreak, while urging governments to avoid panic and fear over an easily preventable disease.

The epidemic, the worst since Ebola was first identified in 1976, has killed 1,013 people since early this year, the WHO said.

The West African regional bloc ECOWAS said Ebola had killed one of its officials in Nigeria, taking the number of deaths there to three.

Cases have so far been limited to Guinea, Liberia and Sierra Leone, which account for the bulk of victims, and Nigeria.

Fear has gripped the impoverished countries ravaged by the disease, with harrowing tales emerging of people being shunned by their villages as the virus kills those around them.

In the Liberian village of Ballajah, 150 km from the capital Monrovia, 12-year-old Fatu Sherrif was locked away with her mother's body without food and water for a week.

Her cries went unanswered as panicked residents fled the village when both her parents became sick.

Fatu later died and her brother Barnie, 15, despite testing negative for Ebola, was left alone and hungry in an abandoned house.

Elderly Spanish priest Miguel Pajares, who became infected while helping patients in Liberia, died in a Madrid hospital on Tuesday, five days after being evacuated.