STOCKHOLM: The European Union’s health agency said on Wednesday there was no evidence that the Andes strain of hantavirus had mutated following a deadly outbreak aboard a cruise ship travelling from Argentina to Cape Verde.
The outbreak, linked to the Dutch vessel MV Hondius, has resulted in the deaths of three passengers and triggered international health monitoring efforts.
Seven other passengers have been confirmed to have the virus, including a French woman reported to be in critical condition. An eighth case is considered probable, health officials said.
All passengers identified as infected or at risk have been evacuated from the vessel and placed in quarantine.
“Preliminary investigations based on the whole genome sequencing that is available to us suggest that there are no indications that this virus is acting any differently from the known virus circulating in some regions of the world,” Andreas Hoefer of the European Centre for Disease Prevention and Control (ECDC) told journalists.
Hoefer, a microbiologist and molecular epidemiologist at the Stockholm-based agency, said all virus sequences analysed so far were “virtually identical”.
“That means that there is likely only a single transmission event from an infected animal to a human,” he added.
Hantavirus is typically spread through exposure to infected rodents, particularly via urine, saliva and droppings.
Laboratory testing conducted in South Africa and Switzerland confirmed the infections involved the Andes strain of hantavirus, the only known hantavirus strain capable of spreading between humans.
There are currently no vaccines or specific treatments available for the disease.
The ECDC and the World Health Organization recommend a 42-day quarantine and close monitoring of high-risk contacts because the virus can incubate for up to six weeks.
“Due to the long incubation period, it is still possible that more cases among the passengers who are now actually in quarantine will occur,” ECDC Director Pamela Rendi-Wagner said.
“This cannot be excluded,” she added.
Gianfranco Spiteri, head of global epidemic intelligence and health security at the ECDC, said the risk of transmission was highest among symptomatic individuals.
However, he cautioned that infected people might still be contagious during the early stages before symptoms appear.
“So in terms of taking a preventive and highly precautionary approach, we recommend, for example, that contact tracing should be done for two days before the onset of symptoms as well,” Spiteri said.
