After days of growing panic and uncertainty for the passengers of the MV Hondius, who, isolated in their cabins, had to deal with increasingly worrying news, there was something positive to report again. The expedition cruise ship has been given the green light by Spain to dock in the Canary Islands – after Cape Verde previously refused the ship.
There are currently four medical professionals on board to keep an eye on things. On Thursday morning, the last of three people evacuated from the ship early landed at Schiphol. At least two of them are infected with the hantavirus and the third had close contact with someone who died on the ship.
The fact that the hantavirus was only diagnosed for the first time on Saturday, May 2 – a month after the departure of the Hondius from southern Argentina – leads to a lot of uncertainty about the extent of its spread. If the virus had been present on the ship from day one of the voyage, which is the leading hypothesis for the time being, a month of unlimited contact passed. Not only on the ship, but also outside it, for example when the Frisian woman tried to repatriate the body of her deceased husband to the Netherlands but died herself during her stopover in Johannesburg. Five questions about the state of affairs regarding hantavirus infections.
1How many infections are there, and where?
A total of nine people are feared, suspected or confirmed to have the serious variant of the hantavirus, the Andes virus. Three of them have died, and six of them remain in six different hospitals across two continents. A German woman who was hospitalized in Düsseldorf as a precaution was closely related to the German man who died on May 2. She has no complaints.
2What do we know about the origin of the infections on board the ship?
The World Health Organization (WHO) suspects that at least one of the passengers contracted the virus on the Argentine mainland through contact with a rodent via feces or saliva and transmitted it within the cruise ship. The Argentine Ministry of Health recorded a total of 44 cases of the Andes virus, the deadly, human-to-human variant of the hantavirus, from January to April this year. The three people who died from the virus, the Dutch couple and a German man, all traveled extensively through Argentina before boarding the Hondius on April 1. The Argentine ministry is now going to catch rodents in the south of the country for research purposes.
It is less likely that rodents came on board the Hondius and spread the virus themselves. Several (former) passengers have largely debunked that theory, which has been widely shared on social media, in recent days: according to them, the ship is spic and span. Staff and passengers who previously sailed on the Hondius also experience this NRC confirmed.
3To what extent is the spread of the virus under control?
There are currently no people on the Hondius with symptoms of the hantavirus, according to the WHO and Oceanwide Expeditions, the ship’s shipping company. Everyone who is still on board will be quarantined in various places after arrival in Tenerife.
But the various travel movements that passengers made before a South African private hospital diagnosed the hantavirus in a sick passenger on May 2, makes it difficult to predict to what extent the virus could have spread in the meantime.
On April 24, thirty people disembarked from the ship to Saint Helena, from where they continued their journey independently. In addition to the Dutch couple, there was another Dutchman among them. And the Swiss man who is in a hospital in Zurich with the Andes virus also belongs to that group. Oceanwide Expeditions says it has made contact with all those on board who disembarked on April 24.
But more stops have been made, including in Tristan da Cunha and Ascencion. Mapping how many and which people disembarked and boarded “turns out to be quite a job,” says a spokesperson for the shipping company. He suspects that it concerns “very small numbers”, mainly personnel.
Oceanwide Expeditions also does not know how the wife of the deceased Dutchman came from Saint Helena to Johannesburg. Was that via a commercial flight? “That must be the case, but we don’t know which one.”
In any case, the flight that the Frisian woman (69) took from Johannesburg to Amsterdam was commercial. There were a total of 388 people on board that KLM flight. The Dutch woman’s condition deteriorated to such an extent that she was taken off board before departure. She died shortly after getting off the plane.
GGD Kennemerland has personally informed all passengers who sat up to two rows in front of and behind the infected woman. They are asked to measure their temperature daily and to report to their local GGD if they develop complaints. The other passengers received a general message asking them to keep a close eye on themselves. One of the flight attendants on board has now been admitted to the AmsterdamUMC with complaints.
4How do Dutch hospitals receive patients?
The first patient was received on Wednesday at the LUMC in Leiden. Later, a patient was also admitted to RadboudUMC in Nijmegen and AmsterdamUMC. This care is coordinated by the RIVM, which has set up a platform for the outbreak of serious infectious diseases following previous outbreaks of Ebola, the Lassa virus and the Marburg virus. “This is the first time that we have received a patient with the Andes virus, so in terms of measures we had to look at which infection this virus most resembles,” says Karin Ellen Veldkamp, physician-microbiologist and head of the infection prevention department at the LUMC. “We did this in consultation with Chile and Argentina, who have more experience with this.”
The measures are comparable to the Mers virus: the patients are in an isolation room with negative pressure and a lock. The healthcare staff wears FFP2 masks, protective glasses for the eyes, an apron with long sleeves and gloves.
Veldkamp says he will carefully take into account the arrival of more patients in the coming days or weeks. “We try to spread it out a bit [beschermings]measures are less intensive than for Ebola, for example, so in principle all academic hospitals can accommodate these people.”
5Is there a new pandemic?
That is unlikely, says professor and virologist Chantal Reusken, affiliated with the RIVM. The Andes virus behaves differently from the coronavirus: it is in the deep respiratory tract and not, like SARS-CoV-2, in the upper respiratory tract. This makes the virus less likely to spread through the air, only with prolonged or close contact. “That is why a cruise ship is a situation in which something like this could happen,” says Reusken. Another major difference with the coronavirus: there are no indications in the medical literature that people with the Andes virus are already contagious before they have symptoms.
The largest known outbreak of the Andean virus was in Argentina between 2018 and 2019. Then, in one village in Chubut province, 34 people were infected, of whom 11 died. “In that situation we have seen that if you immediately map infected patients and their contacts and introduce the correct isolation measures, the virus can be easily contained,” says Reusken. The current situation is not entirely comparable, because there are more people spread around the world who may be infected without knowing it. “That is why everything is now being investigated epidemiologically as best and as quickly as possible and questions are being asked from everyone who may have been in contact with people on the ship or on the plane.”
During the corona pandemic, there were also concerns that the virus continued to mutate, creating an increasingly dangerous variant. That concern is less with the Andes virus, Reusken explains. “We know that the genetic material of this virus is very stable. If we compare the transmission to humans from 1996 and 2018, the genetic material of the virus appears to have hardly changed.”