A contained hantavirus outbreak, and lessons for the world

As of last week, the World Health Organization (WHO) confirmed five hantavirus infections, including three deaths, linked to the Dutch-flagged cruise ship MV Hondius, which sailed from Argentina on April 1 en route to Cabo Verde in West Africa. The WHO was first notified of the suspected cases on May 2.

Noting that the incubation period for hantavirus infection typically ranges from one to eight weeks, the agency said additional cases may still be reported. The virus involved has been identified as the Andes variant, the only hantavirus species known to be capable of limited person-to-person transmission, usually associated with close and prolonged contact.

While acknowledging the cluster of cases as a serious incident, global health authorities assured the public that the outbreak is unlikely to spark a pandemic and that the overall public health risk remains low. “This is not coronavirus, and not the start of a COVID pandemic,” said Dr. Maria Van Kerkhove, director of the WHO’s Department of Epidemic and Pandemic Threat Management.

The WHO has deployed an expert on board the ship to support a comprehensive medical assessment of passengers and crew, while gathering critical information to evaluate potential exposure risks. The mission is being supported by physicians from the Netherlands and an expert from the European Centre for Disease Prevention and Control. Meanwhile, the Philippines’ Department of Health (DoH) has likewise reported that none of the 38 Filipino crew members aboard the ship is exhibiting symptoms of hantavirus infection.

The WHO also arranged the shipment of 2,500 diagnostic kits from Argentina to laboratories in five countries to strengthen their testing capacity. It is developing operational guidance for the safe and respectful disembarkation and onward travel of passengers and crew upon arrival. The priorities are clear, and these are to ensure that affected patients receive appropriate care, protect remaining passengers and crew, and prevent any further spread of infection.

Although the outbreak appears contained, the incident serves as a reminder that infectious disease threats can emerge unexpectedly and spread rapidly across borders in an interconnected world.

Hantaviruses are rodent-borne viruses that can cause severe and sometimes fatal disease in humans. People usually become infected through contact with infected rodents or exposure to their urine, droppings, or saliva. In Asia, hantaviruses are commonly associated with hemorrhagic fever with renal syndrome (HFRS), which may initially present with fever, headache, muscle pain, and gastrointestinal symptoms such as abdominal pain, nausea, or vomiting. In severe cases, patients may develop low blood pressure, bleeding disorders, and kidney failure.

While there is no specific cure for hantavirus diseases, early supportive medical care significantly improves survival. This includes close monitoring and management of respiratory, cardiac, and kidney complications.

Preventing infection largely depends on reducing contact between people and infected rodents. Homes and workplaces should be kept clean, openings that allow rodents to enter buildings should be sealed, and food should be stored securely. Safe cleaning practices in rodent-contaminated areas are likewise important. Wet contaminated surfaces with disinfectant before cleaning to avoid stirring virus particles into the air.

The swift and coordinated response to the cruise ship incident underscores the importance of global cooperation, preparedness, and innovation. In particular, the International Health Regulations (IHR) enabled close coordination among the WHO and multiple countries involved in the response. The IHR serves as a global early warning framework that requires countries to report certain outbreaks while helping minimize unnecessary disruptions to international travel and trade.

The IHR was amended in 2022 and 2024 to strengthen global emergency response mechanisms. The innovative pharmaceutical industry, represented by the International Federation of Pharmaceutical Manufacturers and Associations (IFPMA), actively participates in discussions surrounding the implementation of these amendments, with the shared goal of improving surveillance, preparedness, and the timely declaration and management of public health emergencies.

While the hantavirus outbreak aboard the cruise ship is unlikely to become a pandemic, many health experts continue to warn that pandemics will remain a persistent global threat as pathogens can spread rapidly across countries. According to risk modeling estimates from data and analytics company Airfinity, there is a 27.5% chance of a pandemic similar to COVID-19 occurring within the next 10 years.

The COVID-19 pandemic demonstrated the importance of preparedness and collaboration among governments, regulators, healthcare systems, scientists, and the biopharmaceutical industry. Medicines and vaccines developed through these partnerships were essential in cushioning the impact of the pandemic and saving millions of lives worldwide.

The innovative biopharmaceutical industry has since translated lessons learned from COVID-19 into concrete commitments. Vaccine innovators and manufacturers jointly endorsed the Berlin Declaration, pledging to reserve a portion of real-time production of vaccines, treatments, and diagnostics for priority populations in lower-income countries. The industry has also proposed additional measures to strengthen equitable access to essential medical countermeasures before and during future pandemics.

The biopharmaceutical industry remains committed to supporting stronger pandemic preparedness. One important goal is the development of safe and effective pandemic products within 100 days of a new pandemic declaration. Another is continued collaboration with governments, regulators, multilateral institutions, and healthcare stakeholders to help ensure equitable access to medicines and vaccines, particularly for vulnerable populations.

In an increasingly interconnected world, preparedness, cooperation, and innovation will remain among our strongest defenses against future health emergencies.

Teodoro B. Padilla is the executive director of Pharmaceutical and Healthcare Association of the Philippines, which represents the biopharmaceutical medicines and vaccines industry in the country. Its members are at the forefront of developing, investing and delivering innovative medicines, vaccines, and diagnostics for Filipinos to live healthier and more productive lives.