An outbreak of a rare but potentially deadly virus on a cruise ship in the South Atlantic is being closely monitored but poses a low risk to the Gulf and is unlikely to develop into a Covid-style pandemic, experts say.
Eight cases have been reported so far, according to the World Health Organisation (WHO), including three deaths, on the MV Hondius, which set sail from Argentina a month ago. Five of the eight cases have been confirmed as hantavirus. The hantavirus involved is the Andes virus, the only strain known to be capable of limited transmission between humans, linked to close and prolonged contact.
The vessel, carrying roughly 150 people, is now en route to Europe and is expected to arrive in Spain on Saturday or Sunday.
WHO said the outbreak was not the start of a pandemic. But it and national authorities are taking the situation seriously. How concerned should we be?
What is the hantavirus?
Hantaviruses are a collection of viruses that cause serious illnesses and, in some cases, can be fatal, according to the Centres for Disease Control and Prevention in the US.
Infection typically occurs through inhalation of air that is contaminated with particles from rodent urine and droppings.
If infected, patients can develop fever, fatigue, muscle aches and respiratory illnesses. In rare cases those affected can develop haemorrhagic fever and kidney failure requiring hospital treatment. Symptoms usually appear after between two and four weeks, but it can take longer.
Hantavirus can have a case fatality rate of about 1 to 15 per cent in Asia and Europe and up to 50 per cent in the Americas, WHO data shows.
Dr Yazeed El Khaleq, a consultant pulmonologist specialising in the diagnosis and treatment of complex respiratory and lung conditions at Burjeel Hospital in Abu Dhabi, told The National the risk remains low as it is not easily transmitted between people.
“Human-to-human transmission is limited to one strain,” he said. “And only after prolonged exposure to anyone infected.”
How did this outbreak start, and are cruises particularly susceptible?
It is still not clear how this outbreak started, but authorities are investigating.
The cruise ship had been travelling to remote areas, so there is a possibility this is how someone encountered it. Conditions onboard may also have played a role, as passengers share common areas, lifts and dining halls, meaning infections can spread rapidly.
For example, during Covid-19 the Diamond Princess had an outbreak in which more than 600 passengers and crew caught the virus. Norovirus, the vomiting bug, is also linked to cruises. Age also matters. Cruises are popular with older people who can have pre-existing conditions, making infections more deadly.
People can take regular prevention measures, such as washing hands, and avoid shared areas if feeling unwell. “The important thing is to detect, isolate and contact trace,” said Dr El Khaleq. “Hospitals will usually admit anyone who has the virus, as it is rare.”
Could this become a pandemic like Covid-19?
The WHO on Thursday said the outbreak is not the start of a pandemic.
“We believe this will be a limited outbreak if the public health measures are implemented and solidarity is shown across all countries,” said Dr Abdirahman Mahamud, WHO’s alert and response director. Dr El Khaleq agreed, saying the risk to public health in the UAE and wider Gulf region is “extremely low”.
“There was an outbreak in Argentina in 2018 which was limited and controlled quickly. After this, the UAE tested rodent species as a precautionary measure and all came back negative. The UAE is always very responsive," he said. “I don’t think we are at risk of a pandemic such as Covid-19."
Dr El Khaleq said there is “very good resilience in the Gulf” and that lessons were learnt from Covid-19, "but as WHO said, this is not like Covid-19”.
“With Covid-19, human-to-human is the root transmission. Even a sneeze does the job, and it occurs a short time after coming into contact,” he said. “Only one strain of the hantavirus causes human-to-human transmission, and you need to be in close contact for a long time to get enough of the viral load.”
Can the virus be treated?
There is no cure or specific vaccine for the virus but medics can offer supportive treatment.
According to Dr El Khaleq, these treatments can vary as patients can experience different health complications. “If a patient develops kidney issues, there is dialysis,” he said. “Or, if there are heart issues, there is medication to support the heart muscle and decrease inflammation.”
Anyone with symptoms should consult a doctor, self-isolate and wear a medical mask if they have respiratory symptoms. Dr El Khaleq said the most important advice was for travellers going to South America or places where the virus appears.
“People should avoid contact with rodents and, if camping, should not walk barefoot. They should practise strong personal hygiene,” he said. "If respiratory symptoms are present, practice respiratory etiquette and wear a medical mask. If symptoms develop, consult a doctor and get tested.”
What happens next?
The MV Hondius is expected in Tenerife, Spain, at the weekend. Medical teams are on standby for its arrival and passengers will be assessed onboard. WHO said it was prepared to offer support.
"The ship is now sailing for the Canary Islands, and we are confident in the capacity of Spain to manage this risk, and we are supporting them to do so," WHO director general Dr Tedros Adhanom Ghebreyesus said on Thursday. "We assess the risk to the people of the Canary Islands as low."
WHO has taken a number of actions since it was notified of the situation on May 2 including deploying an expert on board the ship.
