The World Health Organization has confirmed two cases of hantavirus infection and identified five additional suspected cases aboard a cruise ship stranded off the coast of Cape Verde.
Also, three deaths have already been reported.
According to the global health body, the outbreak involves a cluster of severe respiratory illnesses affecting both passengers and crew on the vessel.
One patient is currently in critical condition, while others are being closely monitored as containment efforts continue.
Health authorities are also extending contact tracing beyond the ship.
WHO said it is working to locate passengers who were on an April 25 flight between Saint Helena and Johannesburg, after one infected individual who had been on that route later died.
The cruise ship, carrying approximately 150 people, has been unable to dock as precautionary measures remain in place.
Most passengers are being kept in isolation within their cabins while investigations and testing continue.
Hantavirus is a rare but potentially severe disease typically spread to humans through contact with infected rodents, especially via urine, droppings, or saliva.
While human-to-human transmission is uncommon, the WHO noted that limited transmission has been observed in rare cases involving specific strains of the virus.
Despite the seriousness of the situation, the WHO has assessed the overall global risk as low.
It added that it is closely monitoring developments and coordinating response efforts with international health authorities to contain the outbreak.
