Questions and answers on the hantavirus outbreak in a cruise ship

What is hantavirus and the Andes strain?

Hantaviruses are a group of viruses that people usually catch through particles from infected rodents. It can cause serious illness, and the symptoms depend on the type of hantavirus involved. The Andes virus, which is involved in this outbreak, is a hantavirus primarily found in South America that can lead to a severe lung infection called Hantavirus Pulmonary Syndrome, which can worsen quickly and become life-threatening.

How do you catch hantavirus, and how infectious is it?

Hantavirus mainly spreads via inhalation of contaminated particles from the urine, faeces or saliva of infected rodents. Only one strain, Andes – the one involved in this outbreak – can spread between people. However, it only does so in very specific, close contact situations. Hantavirus can be very dangerous for the person who gets sick, but does not pose the same broad outbreak risk as SARS, or COVID‑19.

Can Andes hantavirus spread between people?

Andes hantavirus, which is involved in this outbreak, is found mainly in South America and is the only hantavirus that is known to spread between people. Nevertheless, such transmission is considered rare and typically requires close or prolonged contact with an infected person.

How many people have been infected in this outbreak?

For the latest figures, check ECDC's page for this outbreak.

How were people infected?

The current hypothesis is that at least one passenger was exposed to Andes virus while spending time in Argentina or Chile, where Andes virus is endemic, before boarding the ship, and may subsequently have transmitted the virus to other passengers onboard. 

What is the risk to the general public in Europe?

The risk to the general population in Europe is very low. 

The Andes virus does not spread easily between people, and the types of contact needed for transmission are uncommon outside very close personal settings. In addition, the rodents that normally carries this virus do not live in Europe, so ongoing spread through animals is not expected.

Is it likely that the virus spread beyond the cruise?

At least 26 passengers are known to have disembarked in St. Helena and travelled back home or to other destinations. The World Health Organization (WHO) has shared details with the relevant countries, and they are being recommended to contact their local public health teams for advice.  Contact tracing is being carried out to ensure follow-up with those who may have been exposed.

Even if transmission of Andes virus were to occur from passengers leaving the ship, the virus does not spread easily between people. It is therefore unlikely that the infection will spread more widely, particularly if authorities act to prevent and control the outbreak. The rodent that carries Andes virus is native to South America and not found in Europe, so it is unlikely the virus would spread to local rodents. 

What is the current situation on board the ship?

According to the ECDC expert on the ship, there are currently no people with symptoms on board. Passengers are wearing masks and the ship is operating at around half capacity, allowing space for social distancing. 

How do I handle misinformation and how do I know what information on the outbreak is accurate? 

When disease outbreaks happen, like the hantavirus outbreak on the cruise ship, people may feel worried or scared. There are often many unknowns during an outbreak, and the situation can change quickly. It is natural that people look for answers to their questions and concerns, and may develop their own theories about why an outbreak is happening. 

Along with an outbreak, you will often see a surge of misinformation. Believing in misinformation depends on many factors, such as whether people trust the source or if it fits with their prior knowledge or beliefs. Our information environment, steered by algorithms, also plays a large role in what kind of misinformation and correct information we encounter. 

When it comes to outbreak information, it is always best to consult the websites and social media channels of official verified health authorities in your country, or international ones like ECDC and WHO.

Is there a vaccine or specific treatment?

There is no vaccine for hantavirus and treatment focuses on relieving symptoms and supportive care. 

What will happen now that the ship will be allowed to dock in Tenerife?

People who develop symptoms will be assessed quickly and, if needed, evacuated to hospitals that can provide intensive care. Anyone with symptoms will be tested after leaving the ship, but a negative test doesn’t always rule out infection, so follow-up is still important. 

While on board, passengers and crew should be asked to wash hands often, wear masks, keep distance, and monitor themselves for any signs of illness. Healthcare workers caring for sick passengers should use protective gear to prevent close contact transmission, and stronger precautions are used if procedures could create airborne particles. Passengers and crew who leave the ship should receive clear instructions on what to do and what symptoms to watch for until doctors can confirm whether they are infected. 

ECDC is working with Spanish authorities and the World Health Organization (WHO) to develop protocols for safe disembarkation, repatriation and public health follow-up of passengers and crew leaving the ship.

Why are public health authorities concerned about this outbreak?

This outbreak is concerning for the following reasons:

• While humans can usually only get a hantavirus infection from contact with contaminated particles from rodents, this outbreak involves the Andes strain, which can spread between humans, although this happens rarely.
• Infection with Andes virus has a high fatality rate, as it can cause a life-threatening condition called Hantavirus Pulmonary Syndrome.
• People can spread the virus before they start showing symptoms, and it can take up to two to eight weeks for symptoms to appear. This can make it challenging to control the outbreak.
• There is no treatment to tackle the infection or vaccine for the Andes virus, and treatment focuses on addressing symptoms.

What is ECDC doing to help control the outbreak?

ECDC is supporting the response operations through the EU Health Task Force – an EU rapid-response team coordinated by ECDC that helps countries prepare for and respond to cross-border health threats and outbreaks – both remotely and on the cruise ship in coordination with the affected countries. 

There is also ongoing collaboration with partners and relevant countries on protocol for management of cases and contacts of cases, and ECDC is producing epidemiological updates with the latest data.