Image copyright AFP Image caption Ebola is one of the world's most virulent diseases

A Canadian man in hospital with symptoms of a haemorrhagic fever resembling Ebola has tested negative for the virus, a health official says.

The man had recently returned from a trip to West Africa, which is suffering a deadly outbreak of Ebola.

Isolated in a critical condition in Saskatoon, Saskatchewan province, tests also cleared the man of Marburg virus, Lassa fever and Rift Valley fever.

His illness may be severe malaria, said the World Health Organization (WHO).

Gregory Hartl, the WHO's head of public relations, tweeted the preliminary results on Tuesday.

There is said to be no risk to the public.

Sixty-one people have died in an Ebola outbreak in the remote forests of southern Guinea.

Suspected cases have also been reported in the neighbouring countries of Liberia and Sierra Leone.