Two people who were onboard a cruise ship hit with a deadly outbreak of hantavirus have returned to the UK and are self-isolating, British health officials have said.

Neither of the two British people, who left MV Hondius at St Helena in late April, are reporting symptoms, according to the UK Health Security Agency (UKSA).

A British crew member was medically evacuated from the ship after falling ill and flown to the Netherlands for specialist care.

Three people on the MV Hondius have died since 11 April. As of Thursday, there have been eight suspected cases, three of which were confirmed as hantavirus – a rare family of viruses carried by rodents – by lab testing, according to the World Health Organization (WHO).

“It’s important to reassure people that the risk to the general public remains very low,” said Dr Meera Chand, deputy director for epidemic and emerging infections at the UKHSA.

“We are standing up arrangements to support, isolate and monitor British nationals from the ship on their return to the UK and we are contact-tracing anyone who may have been in contact with the ship or the hantavirus cases to limit the risk of onward transmission.”

It is understood 19 British nationals were listed among the 150 passengers on the cruise, which was sailing from Argentina to Cape Verde, with four British crew members. The outbreak has been linked to a birdwatching expedition in Argentina joined by two passengers before they boarded the ship.

Officials in Argentina, from where the cruise departed, are scrambling to determine if the country was the source of the deadly outbreak. The Latin American country, which has reported 101 hantavirus infections since June 2025, is consistently ranked by the WHO as having the highest incidence of the rare, rodent-borne disease.

The UK health agency said once the ship docks in Tenerife, the remaining British nationals can be repatriated if they do not develop symptoms. It said none of the British nationals onboard are currently reporting symptoms, but they are being closely monitored.

Spain’s health minisuer Monica Garcia said on Wednesday that none of the passengers left onboard the ship were presenting symptoms of the disease and would be repatriated to their countries. The 14 Spaniards on board would be flown to a hospital in Madrid to quarantine, Spanish Health Minister Monica Garcia said on Wednesday.

Among the three individuals medically evacuated from the ship on Wednesday was British crew member Martin Anstee. The expedition guide and former police officer was flown to the Netherlands and spoke from hospital saying: “I’m doing OK. I’m not feeling too bad. There are still lots of tests to be done.”

It was a “good sign” Anstee was able to communicate with family, said Prof Robin May, chief scientific officer at the UKHSA, adding that he would be under investigations for some time. May also told BBC Breakfast on Thursday that the two British nationals who left the cruise earlier on its course had returned to the UK before the outbreak was detected.

“There’s a chance they may have been exposed to the virus, so we have been in contact with them. They have agreed very kindly to self-isolate for the next period of time,” said May, who said the same process would apply to other British nationals onboard.

May said hantaviruses as a group are widespread across the world. The viruses naturally infect rodents and are “occasionally” transmitted to humans, according to the WHO, through contact with infected rodents or their urine, droppings or saliva.

A focus is an Andean strain, which has shown evidence of limited human to human transmission in the past among close contact, according to the WHO. Found in South American, it can cause a severe and often fatal lune disease called hantavirus pulmonary syndrome. Found in Europe and Asia, the viruses can cause haemorrhagic fever with renal syndrome.

May said the Andes virus strain has been studied intently because it is “such a severe disease” and there were global efforts to develop vaccines against it.

“This is not a virus that spreads easily between humans,” he added, but given it can spread between individuals, “we are contact tracing everyone who might have been in close contact.”