WHO sees Hantavirus outbreak after cruise as nearing its end

A total of 13 cases have been recorded during the course of the outbreak, including three deaths. According to the WHO, this number has not changed since the last update. „Die Gesamtzahl der Fälle liege weiter bei 13, darunter drei Todesfälle“, heißt es in der Mitteilung.

Cases in South Africa contained

In addition to the known cases on board the cruise ship, two further infections had been identified in South Africa, the WHO reported. All contacts of these two cases have since completed their monitoring period, with no further illnesses reported. This strand of the outbreak is therefore considered contained.

In Spain and in the Netherlands as well, the quarantine and observation periods for affected contacts have expired. The WHO interprets this as a further sign that the virus has not spread beyond the known clusters. The health authorities in the affected countries had provided medical support to those affected during the incubation period.

Monitoring continues

30 contacts would still be monitored, Tedros Adhanom Ghebreyesus wrote. Such monitoring is standard for hantaviruses because the time between infection and onset of illness can be several weeks. Only after the full observation period has elapsed without new cases does the WHO typically classify an outbreak as over.

Weeks earlier, the WHO had assessed the risk for the general population as low and affirmed that there was no danger of a major wave of infection or a pandemic. The current update also emphasizes that the outbreak remains limited to the documented cases and their closest contacts. There is no elevated risk of infection for the general public.

Special features of the Andes virus

The Andes virus is considered the only hantavirus for which limited human-to-human transmission can occasionally occur. This characteristic distinguishes the pathogen from most other hantaviruses, which are usually transmitted to humans by rodents. The WHO has taken this transmission route into particular account when tracing contacts.

Hantaviruses are typically transmitted from rodents to humans, for example through dust stirred up that contains fecal particles from the animals. Travelers to endemic areas are advised to avoid contact with rodents and their droppings. The cases on the "Hondius" show that outbreaks can occur even when travelers are not moving through rural regions but are staying on board a ship.

Transmission by rodents

The shipping company Oceanwide Expeditions had cooperated with the authorities of the affected countries and with the WHO after the infections became known, in order to bring the passengers safely to their home countries. The evacuation via Tenerife was carried out under special safety precautions to prevent any possible spread of the pathogen during transport.

The WHO monitors hantavirus outbreaks worldwide and exchanges information with national health authorities. In the current case, information from Argentina, Spain, the Netherlands, and South Africa was incorporated into the assessment. The authorities in these countries each conducted their own investigations into infection chains and contacts, according to the report.

With the expiration of the observation periods in Spain, the Netherlands, and South Africa, the outbreak is approaching its end in the WHO's assessment. Should no new cases occur in the coming weeks, the WHO is expected to officially declare the outbreak over. The organization announced that it would continue to monitor the situation and publish new information if necessary.

Previous deaths and effectiveness of measures

The WHO also pointed out that hantaviruses are widespread in many parts of the world and that travelers should inform themselves about the risks in their destination regions. This includes guidance on accommodations, campsites, and rural areas where rodents may be present. Prevention remains the most effective tool against infection.

Overall, the WHO assesses the outbreak as spatially and temporally limited. The deaths to date underscored the seriousness of the disease, but spread outside the documented contact chains did not occur. The authority sees this as confirmation that the measures introduced — quarantine, contact tracing, and safe repatriation — were effective.

The case illustrates how quickly cross-border health events are perceived today. Even though the risk for the general population is classified as low, the example shows how important a coordinated response is between shipping companies, national authorities, and international organizations such as the WHO. (dpa)