Two Britons who were medically evacuated from the hantavirus-hit cruise ship are improving, global health officials have said.

A British passenger, understood to be a 69-year-old man, was taken to South Africa on 27 April and is receiving care at a private health facility in Sandton, Johannesburg.

Another Briton, Martin Anstee, 56, an expedition guide, was taken off the MV Hondius on Wednesday and flown to the Netherlands to receive specialist medical care.

Dr Maria Van Kerkhove, from the World Health Organization (WHO), said two patients – known to include a Briton – remained in hospital in the Netherlands and another Briton was in intensive care in South Africa.

She told a WHO press briefing: “I am very happy to say the patient in South Africa is doing better, and the two patients in the Netherlands we hear are stable. So that is actually very good news.”

As of Thursday there are eight suspected cases, five confirmed by lab tests as hantavirus, a rare family of viruses carried by rodents.

The outbreak, linked to three deaths, has been connected to a birdwatching trip to Argentina, Chile and Uruguay that two of the passengers went on before boarding the ship.

Spanish authorities have given permission for the ship to anchor in the Canary Islands, despite concerns from locals and officials, and the boat left the shores of Cape Verde at 3.15pm local time on Wednesday, the tour operator Oceanwide Expeditions said.

It is estimated to arrive at the port of Granadilla in Tenerife in the early hours of Sunday.

Morale on board has improved since the ship started its journey to Tenerife, the WHO said. Two doctors are on board along with infectious disease experts from the WHO and the European Centre for Disease Prevention and Control, who are conducting a medical assessment of everyone on board.

While the risk to the public is low, Dr Tedros Adhanom Ghebreyesus, the director-general of the WHO, said there could be more cases due to the incubation period of the Andes virus – the variant of hantavirus linked to the outbreak – which can be up to six weeks.

He said: “While this is a serious incident, WHO assesses the public health risk as low.” He thanked the ship’s operator for its cooperation, and the passengers and crew, “who are going through a very difficult and frightening situation”.

The WHO is not expecting the outbreak to be an epidemic, according to Dr Abdirahman Mahamud, the director at the alert and response coordination department. He highlighted a similar outbreak in Argentina in 2018-19 which led to 34 cases.

Seven British people were among 30 from 12 nations who left the ship when it docked in the remote South Atlantic island of Saint Helena, including a Dutch woman who became unwell during onward travel and died. The woman was accompanying her husband’s body, which was being repatriated after he died on the ship on 11 April.

On Thursday, a woman in Amsterdam, reported to be a flight attendant who came into contact with the woman who died, came forward with potential symptoms.

Oceanwide Expeditions said guests who had disembarked have been contacted.

The UK Health Security Agency (UKHSA) has been asked whether it can confirm it has been in touch with all seven Britons who left the ship on 24 April.

It has previously announced that two Britons who had already returned from the vessel are isolating at home and do not have symptoms. Contact tracing is happening for anyone who may have sat next to them on the flight home. The two people contacted health officials when they heard about the cases on the ship.

Nineteen British nationals were listed as passengers on the MV Hondius, which was sailing from Argentina to Cape Verde, with four British crew members.

UK health experts said British passengers on board will be asked to self-isolate in the UK for 45 days. Prof Robin May, the chief scientific officer at the UKHSA, said: “For the broader public, not directly involved in this cruise ship, the risk here is really negligible.”

The Foreign Office is arranging a charter flight so the remaining Britons on board the ship who are not displaying symptoms can be repatriated once they dock in Tenerife in the next few days.

According to the UKHSA, none of the British citizens on board are reporting symptoms, but they are being closely monitored.

May said the “most extreme case of incubation” of hantavirus “may be up to eight weeks”, but the general consensus was that people needed to isolate for “probably six weeks, and so that’s the period of isolation, 45 days, that we’re likely to be recommending”.

Three people were taken off the ship on Wednesday to the Netherlands for treatment, including Anstee, an expedition guide and former police officer. Speaking from hospital, he told Sky News: “I’m doing OK. I’m not feeling too bad. There are still lots of tests to be done.

“I have no idea how long I’ll be in the hospital for. I’m in isolation at the moment.”