The first person suspected of contracting hantavirus outside of passengers on the Hondius cruise ship is currently in a Dutch hospital.

She is a flight attendant who came into contact with a former passenger who briefly boarded a KLM flight in Johannesburg, South Africa, but was prevented by airline staff from flying to Amsterdam as she was too sick. 

The woman died shortly afterwards in a Johannesburg hospital. Her husband had died on board the ship on 11 April, the first casualty in the ship’s hantavirus outbreak. She had left the ship at St Helena Island on 24 April to accompany his body home.

Cabo Verde permitted the medical evacuation of three patients, but denied permission for passengers to disembark. The ship has since sailed for Tenerife in the Canary Islands. It is expected to arrive by 11 May, where it is hoped that Spanish authorities will assist passengers to return home. 

However, the President of the Canary Islands, an autonomous community of Spain, has said he will not allow the ship to dock – although the Spanish President has assured the World Health Organization (WHO) that passengers will be able to leave the ship.

Cruise operator Oceanwide Expeditions said that two Dutch infectious disease doctors had joined the cruise to “ensure that optimal medical care can be provided if necessary, during the next stage of this evolving situation”.

The WHO has advised that “all passengers stay in their cabins. The cabins are being disinfected, and anyone who shows symptoms will be isolated immediately”, WHO Director General Dr Tedros Adhanom Ghebreyesus told a media briefing on Thursday.

A WHO expert and an expert from the European Centre for Disease Prevention and Control (ECDC) have also joined the ship.

Together with the two Dutch doctors, they are “conducting a medical assessment of everyone on board and gathering information to assess their risk of infection”, said Tedros.

“WHO is developing a step-by-step, operational guidance for the safe and respectful disembarkation and onward travel journey for all passengers when they arrive in the Canary Islands,” he added.

Tedros thanked Spanish President Pedro Sanchez for his “generosity and solidarity” for agreeing to accept the ship in the Canary Islands, describing the risk to the islands as low.

Eighth patient in Switzerland

Oceanwide Expeditions confirmed that all 30 passengers who disembarked at St Helena on 24 April have been contacted. One, a Swiss national with mild symptoms, is currently in a Zurich hospital.

“The Swiss Federal Office of Public Health (FOPH) has confirmed that a passenger who travelled on the first leg of the voyage has tested positive for hantavirus and is currently being treated at the University Hospital Zurich. His wife, who accompanied him, has not shown symptoms but is self-isolating as a precaution,” the company said in a statement

So far, eight passengers are suspected of hantavirus infection. Three have died, one is in hospital in Johannesburg, three were evacuated from Cabo Verde to undisclosed European hospitals – and the eighth is the Swiss man.

“Five of the eight cases have been confirmed as hantavirus, and the other three are suspected,” said Tedros.

“Hantaviruses are a group of viruses carried by rodents that can cause severe disease in humans. People are usually infected through contact with infected rodents or their urine, droppings or saliva. The species of antivirus involved in this case is the Andes Virus, which is found in Latin America and is the only species known to be capable of limited transmission between humans,” he added.

Collaboration with US

Dr Abdi Mahamud, WHO’s director for Health Emergency Alert and Response Operations, said that each country is responsible for repatriating citizens from the ship and tracing any citizens who may have had contact with those exposed to the virus.

Although the US decided to leave the WHO, it has citizens on board the ship and Mahamud said that collaboration with the US CDC is “going very well on a technical level”.

US CDC officials have joined meetings of the Global Outbreak Alert and Response Network (GOARN) “so the information flow is there, transparent and frank, and information sharing”, he added.

The US remains party to the International Health Regulations (IHR), which stipulates the conduct of countries in the event of disease outbreaks, and was receiving formal communication on the outbreak through that.

“This outbreak shows why the world needs a global entity that coordinates,” added Mahamud, also commending Argentina – which also quit the WHO – for coming forward with information, as the cruise started in that country.

Dr Anais Legand, WHO technical lead on viral haemorrhagic fevers, described “excellent collaboration” with her counterpart at US CDC, including sharing of technical assessments almost every day.

Long incubation

Mahamud confirmed that the incubation period for the virus is up to six weeks, but that only confirmed cases needed to isolate. 

Contacts of cases need “active monitoring”, which was up to host countries to define, he added.

At this stage, PCR testing by South African and Senegalese scientists had confirmed the Andes virus, a species of hantavirus found mostly in Argentina – which is where the cruise started.

Scientists are currently engaged in genome sequencing of the virus to see whether it was the same as that from an Argentinian outbreak in 2018, which affected 34 people, said Mahamud.

This is the only other known instance of human-to-human transmission. That outbreak evolved from an infected person who attended a concert.

Dr Maria Van Kerkhove, WHO’s Director of Epidemic and Pandemic Management. stressed the importance of “global solidarity”, adding that the WHO has “pulled together all of the global experts related to hantaviruses, in particular the Andes Virus”, to assist in managing the outbreak.