Passengers from the cruise ship struck by a hantavirus outbreak are being evacuated and sent to their home countries to isolate and receive medical treatment if necessary.
Some other passengers from MV Hondius left on earlier flights or connections and their contacts are now being traced as a precuation.
Officials say the risk of the infection spreading to the general public remains low.
Crew and passengers now face having to self-isolate for more than a month to avoid any potential spread.
Three died either on board or after travelling on the ship, which set sail from Argentina a month ago. Four others were medically evacuated from the ship for treatment.
So how worried should we be?
‘This is not Covid’
In an update on Thursday, Dr Maria Van Kerkhove from the World Health Organization (WHO) stressed it was not the start of a pandemic, saying: “This is not Covid, this is not influenza, it spreads very, very differently.”
Unlike diseases such as measles, which are highly contagious and spread easily, the Andes strain of hantavirus behind the outbreak is not that infectious.
Human-to-human spread is possible but the risk of infections globally remains low, says WHO.
In a latest update, it says nine cases – seven confirmed by tests – have been identified in people who were on the ship.
It is still not clear how the outbreak started.
Hantavirus typically spreads from rodents, with people infected by breathing in air contaminated with virus particles from rodent urine, droppings, or saliva.
The cruise had been visiting remote wildlife areas, so a passenger could have come into contact with the virus then, or before boarding the ship.
Experts have observed the Andes strain spreading between human patients in previous outbreaks, through very close contact, and health experts believe that some of the infections on board MV Hondius may have passed between people.
Even luxury cruise ships have relatively cramped or restricted living conditions, with people sharing cabins and dining areas – places where infections could spread.
