WHO Announces Hantavirus Outbreak Is Over

The World Health Organization (WHO) has officially declared the international hantavirus outbreak linked to the expedition cruise ship MV Hondius over, marking the end of a weeks-long public health response that involved authorities across more than 30 countries.

The announcement came after the final identified contact of an infected passenger completed the recommended quarantine period, tested negative for the virus and was cleared by health officials. No additional cases have been reported since 25 May, allowing the WHO to conclude that the outbreak has been successfully contained.

The outbreak attracted global attention earlier this year after several passengers and crew members aboard the MV Hondius developed severe illness during an expedition voyage that began in Argentina. Investigations later confirmed that the infections were caused by the Andes virus, a rare strain of hantavirus known to circulate mainly in Argentina and Chile. Unlike most hantaviruses, the Andes strain has the unusual ability to spread between people through prolonged close contact, although such transmission remains uncommon.

The #hantavirus outbreak is over.

However, @WHO will continue working with governments and partners to advance our understanding of the cause of this outbreak and of hantavirus more generally.

My thanks to all countries that supported the response, in line with the… pic.twitter.com/FMGHA7QOe5

— Tedros Adhanom Ghebreyesus (@DrTedros) July 2, 2026

In total, health authorities recorded 13 cases, including three deaths, during the outbreak. More than 650 contacts were identified and monitored in 33 countries and territories, making it one of the largest international contact-tracing operations involving hantavirus in recent years.

Throughout the response, the WHO repeatedly stressed that the overall risk to the wider public remained low. Experts explained that hantaviruses are typically transmitted through contact with the urine, droppings or saliva of infected rodents rather than through casual contact between people. The Andes virus is the only known hantavirus capable of limited human-to-human transmission, and even then, infections generally require prolonged close exposure to someone who is already showing symptoms.

The cruise ship outbreak prompted an extensive international effort involving public health agencies, laboratories and governments to trace passengers after they returned to their home countries. Those identified as close contacts were monitored for several weeks because the virus can have a relatively long incubation period before symptoms appear. The coordinated response helped health officials detect additional cases quickly while preventing further spread.

Today, the final contact of a person exposed to #hantavirus on the cruise ship MV Hondius completed their quarantine period, tested negative and returned home. No further cases have been reported since the 25th of May. Therefore, @WHO considers the hantavirus outbreak over. pic.twitter.com/ePQnylyo0k

— Tedros Adhanom Ghebreyesus (@DrTedros) July 2, 2026

Despite declaring the outbreak over, the WHO has emphasised that its work is far from finished. The organisation says it will continue collaborating with governments and scientific partners to improve understanding of the virus, particularly the rare person-to-person transmission associated with the Andes strain.

The agency is also coordinating an international research project involving 21 countries to better understand how the disease develops and to support the future development of improved diagnostic tests, treatments and vaccines. At present, there is no specific antiviral treatment or licensed vaccine for hantavirus infection, making early diagnosis and supportive medical care particularly important.

Health experts say the outbreak also highlights the importance of international cooperation in responding to infectious diseases that cross borders. Rapid communication between countries, efficient contact tracing and coordinated laboratory testing played a central role in bringing the outbreak under control.

For travellers, the WHO has not introduced any new travel restrictions linked to hantavirus. Instead, officials continue to recommend simple preventive measures, particularly for people visiting rural or wilderness areas where infected rodents may be present. These include avoiding contact with rodent droppings, ensuring accommodation is clean and well ventilated, and following local public health guidance when travelling in affected regions.

While the conclusion of the outbreak is welcome news, public health specialists caution that hantavirus remains a naturally occurring disease in parts of the Americas. Continued surveillance and scientific research will therefore remain essential to ensure that future cases are identified quickly and managed effectively.

The successful containment of the MV Hondius outbreak demonstrates how coordinated international public health measures can prevent isolated incidents from developing into wider global health emergencies, offering reassurance while reinforcing the importance of ongoing vigilance against emerging infectious diseases.