In May 2026, the World Health Organization reported an outbreak of Andes hantavirus linked to a cruise ship, with cases confirmed across multiple countries. While the risk to the general public remains low, the outbreak has brought renewed attention to hantavirus — a zoonotic disease transmitted primarily through contact with infected rodents.
Below, we explain what hantavirus is, how the 2026 outbreak unfolded, the role that rodent populations play in disease transmission, why the WHO has identified environmental management as a key prevention measure, and how proper waste disposal (including the safe destruction of infectious materials) supports both outbreak response and longer-term disease prevention.
What Is Hantavirus?
Hantavirus disease is a zoonotic viral disease caused by hantaviruses of the genus Orthohantavirus, family Hantaviridae, order Bunyavirales. More than 20 viral species have been identified within this genus. Human hantavirus infection is primarily acquired through contact with the urine, faeces, or saliva of certain species of infected rodents, or by touching contaminated surfaces. Exposure typically occurs during activities such as cleaning buildings with rodent infestations, though it may also occur during routine activities in heavily infested areas.
Human cases are most commonly reported in rural settings where rodent populations are present and opportunities for exposure are greater. Of particular concern is Andes virus (ANDV), which is endemic in South America with confirmed circulation and human cases reported primarily in Argentina and Chile, and additional cases identified in Uruguay, southern Brazil, and Paraguay. ANDV is the only hantavirus for which human-to-human transmission has been reported.
What Happened on the MV Hondius?
On 2 May 2026, the WHO received notification from the United Kingdom’s IHR National Focal Point regarding a cluster of severe acute respiratory illness aboard MV Hondius, a Netherlands-flagged expedition cruise ship carrying passengers and crew from 23 countries, including nine EU/EEA nations. As of 27 May, a total of 13 cases (11 laboratory-confirmed and two probable) had been reported, with three deaths, representing a case fatality ratio of 23%.
Contact tracing has identified more than 600 contacts across 32 countries, with approximately 53% classified as high risk and 47% as low risk. High-risk contacts are being quarantined and monitored by local health authorities, with the WHO recommending a quarantine period of 42 days following last exposure.
Based on currently available information, the working hypothesis is that the first case acquired the infection prior to boarding the cruise, through exposure on land. Investigations suggest possible exposure to rodents during recreational activities. Preliminary sequencing analysis shows a high degree of genetic similarity among cases, strongly indicating that the outbreak likely arose from a single zoonotic spillover event.
Current evidence suggests subsequent human-to-human transmission occurred onboard the ship, facilitated by close living quarters, shared indoor spaces, and prolonged interpersonal interactions.
How Does Hantavirus Spread?
Understanding how hantavirus is transmitted is essential to effective prevention and response.
Rodent-to-human transmission
The primary route of human hantavirus infection is through contact with infected rodents. This includes direct contact with rodent urine, faeces, or saliva, as well as touching contaminated surfaces. Exposure typically occurs during activities such as cleaning buildings with rodent infestations or during routine activities in heavily infested areas. Human cases are most commonly reported in rural settings where rodent populations are established.
Human-to-human transmission
Human-to-human transmission has currently only been reported for hantavirus pulmonary syndrome (HPS) associated with Andes virus infection. Based on available evidence, this transmission has typically been associated with close and prolonged interactions, often in shared indoor environments such as households. The largest previously reported ANDV outbreak occurred in Argentina in 2018–2019, where high viral titres combined with attendance at large social gatherings were associated with higher transmission.
The WHO estimates the effective reproduction number for the cruise ship outbreak at 0.7 as of 22 May — anything below 1.0 indicates that the spread of disease is declining. The virus does not exhibit transmission dynamics consistent with highly transmissible airborne pathogens.
What Are the Symptoms and How Serious Is Hantavirus?
Hantavirus pulmonary syndrome can present with fever (38°C or above), myalgia, chills, and acute gastrointestinal symptoms such as nausea, vomiting, diarrhoea, and abdominal pain, as well as acute respiratory symptoms including cough, shortness of breath, chest pain, and difficulty breathing. HPS caused by hantaviruses in the Americas, including Andes virus, can carry a case fatality ratio reaching 40–50%, particularly among elderly individuals and those with co-morbidities. The average age of passengers aboard the MV Hondius was 65 years.
There is currently no approved specific antiviral treatment for HPS. Clinical management is primarily supportive and may include fluid management, respiratory support, and escalation to advanced interventions for severe cases. The European Commission has supported emergency delivery of Favipiravir, an experimental antiviral identified by the European Medicines Agency as a potential treatment for use under clinical trial or compassionate use protocols.
What Is the Risk to the General Public?
The WHO has assessed the risk posed by this event to the global population as low. The European Centre for Disease Prevention and Control has also assessed the risk to the EU/EEA general population as very low.
For people not exposed onboard the ship or through close contact with a confirmed case, the overall probability of infection remains low. Current evidence indicates that human-to-human transmission of ANDV occurs through close and prolonged contact and can be effectively limited through early detection, isolation of cases, and contact tracing. The WHO has advised against the application of any travel or trade restrictions beyond the restriction of movement of identified high-risk contacts.
Why Does Waste Management Matter in Hantavirus Prevention?
The connection between hantavirus and waste management operates on two levels: managing the environmental conditions that the WHO has identified as relevant to rodent control, and safely disposing of infectious materials generated during outbreak response.
Environmental management and rodent control
The WHO has identified environmental management strategies, including rodent control, as a key component of hantavirus prevention efforts. Human cases are most commonly reported in settings where rodent populations are present and opportunities for exposure are greater. Effective waste disposal (reducing the volume of organic waste through proper treatment rather than allowing it to accumulate) contributes directly to these environmental management efforts by limiting the conditions that support rodent habitation.
Sites where waste is poorly managed or left to accumulate in open environments present greater opportunities for rodent populations to establish, increasing the potential for human exposure to hantavirus.
Safe disposal of infectious waste
The WHO’s infection prevention and control guidance for the 2026 outbreak states that waste from suspected or confirmed hantavirus cases should be managed as infectious waste. Standard precautions include appropriate waste management alongside hand hygiene and environmental cleaning. In outbreak settings, particularly in remote locations, aboard vessels, or in areas with limited infrastructure, access to reliable waste disposal cannot be taken for granted.
High-temperature disease outbreak incinerators destroy pathogenic material and reduce waste volume, providing a dependable solution for the safe elimination of contaminated clinical waste in both permanent healthcare facilities and temporary or mobile settings.
How Inciner8 Supports Safe Waste Management and Outbreak Preparedness
Inciner8 has over 20 years of experience providing incineration solutions to healthcare providers, humanitarian organisations, and governments operating in demanding environments across more than 190+ countries. Our systems have been deployed during public health emergencies including Ebola and Covid-19, supplied to the World Health Organization, the United Nations, and the Red Cross.
Our medical waste incinerators safely dispose of infectious clinical waste, contaminated PPE, sharps, and biological materials. Mobile and containerised units are engineered for rapid deployment to remote or infrastructure-limited locations, arriving pre-installed and operational with minimal setup.
Effective waste management serves both as a frontline infection prevention measure during outbreaks and as a longer-term strategy for reducing the environmental conditions that the WHO has linked to rodent-borne disease prevention. From consultation and system design through to installation, and ongoing technical support, we work closely with organisations to deliver reliable, compliant waste management wherever it is needed.
Contact our specialist team to discuss your requirements.
