A shipment of Ebola vaccine candidates set to be used in a clinical trial have arrived in Uganda, where an outbreak has infected 142 people and killed at least 56, health authorities said on Thursday.

Last week Uganda said it had discharged its last Ebola patient from hospital, raising hopes for the end of an outbreak of the deadly haemorrhagic fever declared on September 20.

The WHO had said it would send three vaccine candidates to Uganda to be used in a trial, one by the University of Oxford and Serum Institute of India, another by the Sabin Vaccine Institute and a third by Merck & Co Inc.

At a ceremony to receive the vaccines in Entebbe, about 45 km south of the capital Kampala, Health Minister Jane Ruth Aceng said the 1 200 doses that had arrived were from the Sabin Vaccine Institute.

"Today we are happy that we have the first batch," she said.

"We shall be receiving other doses from Merck and from Oxford."

There are currently no licensed vaccines for the Sudan strain of the virus that caused the infections in Uganda and the trial is to determine whether any or all of the three are effective in combating the Sudan strain.

Existing vaccines combat the more common Zaire strain, which spread during recent outbreaks in the neighbouring Democratic Republic of Congo.

Ebola causes vomiting, diarrhoea, and bleeding from all body orifices, and spreads through contact with the bodily fluids of those infected.

Uganda is counting down towards 42 straight days without any new Ebola cases reported. When that period ends on January 10, it will be declared Ebola-free.

Aceng said even with no new cases reported, the vaccine trial will go on.

"Even if there are no cases, and no contacts and no suspects, the Ministry of Health will still request the scientists to continue with the study."

"Uganda so far has had seven Ebola outbreaks, we may yet again get another Ebola outbreak."