26
May
Hantavirus-Caused Cruise Ship Deaths Raise Disease Transmission, Prevention, and Global Alliance Issues
(Beyond Pesticides, May 26, 2026) Earlier this month, with global attention focused on 12 known or suspected cases of hantavirus, including three deaths, on a cruise ship expedition in the South Atlantic, issues of rodent management, vector control, and disease transmission have made headlines around the world. The incident raises important questions about rodent biology, identification of virus location, method of disease transmission, cleaning practices, and ultimately control and prevention measures that are not harmful to people, wildlife, and ecosystems. The incident also shines a spotlight on the critical importance of the United States’ collaboration in international organizations, particularly the World Health Organization (WHO), in a world of international travel (18 on the ship live in the U.S.), where transmissible diseases extend beyond countries’ borders. With the Trump Administration defunding international programs and withdrawing from WHO, most medical experts agree that the world and U.S. residents are at heightened threat from transmissible diseases that move throughout the world. (See U.S. Abandons International Collaboration on Existential Health Challenges at Time When Most Needed.)
In this context, Beyond Pesticides has launched a local campaign to Tell local officials to use good sanitation and management to prevent rodent problems and not use hazardous rodenticides.
In the cases of this M/V Hondius cruise incident, the first important issue is to identify the virus, where it is found, and how it is transmitted. According to WHO, “It is a rare but severe disease that can be deadly. Although uncommon, limited human-to-human transmission has been reported in previous outbreaks of Andes virus (a specific species of hantavirus).” Moreover, “Andes virus, found in South America [primarily Argentina and Chile], is a currently known hantavirus for which limited human‑to‑human transmission among contacts has been documented,” according to WHO’s Hantavirus “Key fact” factsheet. The individual, who boarded the ship on April 1 from its port of departure in Ushuaia, Argentina, after three months of travel in Argentina, Chile, and Uruguay, was the first to show symptoms on April 6 and died on April 11. On May 2, a cluster of patients showed symptoms, which are expressed as severe respiratory distress.
The European Centre for Disease Prevention and Control (ECDC) set the following protocol: “ECDC has classified all people on board the ship and for the purpose of disembarkation and repatriation to be high-risk contacts; Monitoring/quarantine up to six weeks (42 days); Day 0 = 10 May 2026. [Please note: this follows discussions between ECDC and Member States on 12 May. This text previously stated that Day 0 was 6 May.]; High-risk contacts: self-quarantine, daily symptom monitoring, test if symptomatic; Low-risk contacts: passive monitoring; isolate and test if symptoms develop.” News outlets are reporting passengers have returned to several states, including, including Arizona, California, Georgia, Texas, and Virginia.
From the Centers of Disease Control and Prevention (CDC) in the U.S.: “On May 18, 2026, the Centers for Disease Control and Prevention (CDC) confirmed that 18 recently repatriated U.S. passengers from the M/V Hondius cruise ship were requested to remain at the Nebraska Quarantine Facility through May 31, 2026, which would be the 21-day mark of their monitoring period. Since the passengers disembarked from the ship, three additional cases of hantavirus have been identified — one each in France, Spain, and recently, Canada.” Two passengers who had chosen to leave quarantine were issues mandatory order signed by CDC’s Acting Director and issued under the Public Health Service Act and implementing regulations (42 CFR parts 70 and 71). According to CDC, “Quarantine is a public health measure, available at the federal, state, and county level, and used as necessary to protect communities.”
In the U.S. since 1993, people in the Four Corners area of the U.S. Southwest—the area where Arizona, Colorado, New Mexico, and Utah meet— have faced periodic outbreaks of a different species from the hantavirus on the cruise ship and is not transmitted by people, known as the “New World” hantaviruses. According to CDC, “They are most commonly transmitted (spread) to humans [only] through contact with infected rodents (e.g., urine, droppings, saliva). Rarely, infection can occur from rodent bites or scratches.” 890 cases have been recorded nationwide since 1993, when surveillance began under the Nationally Notifiable Disease Surveillance System (NNDSS). Although the virus is found outside the Southwest, the ecology of the rural areas of the region—including geography, climate, housing patterns, and close human contact with deer mice, the vector—produces ideal conditions for the disease to flourish. Understanding this ecology can help prevent hantavirus outbreaks in humans, as well as other rodent-borne diseases.
Much of the rural American Southwest offers ideal habitat for deer mice (Peromyscus maniculatus), who do well in semi-arid environments, grasslands, woodpiles, sheds, cabins, and outbuildings, and carry the virus without becoming sick themselves. Weather patterns of abundant moisture following drought lead to increased rodent activity. Climate change may also affect risk. The American Southwest has experienced sharper shifts between drought and heavy rainfall. These conditions may periodically boost rodent populations. Wildfires and habitat disturbance may also affect how rodents interact with human communities.
Because people typically become infected by inhaling viral particles from these rodents’ urine, feces, or saliva, it is critical that precautionary steps are taken while cleaning a remote cabin infested with wild rodents—ways to avoid infection. Vacuuming or sweeping up areas that may have been contaminated by live or dead rodents is discouraged because the activity releases viral particles into the air.
Instead, while cleaning:
*Wear gloves.
*Spray the contaminated area with the disinfectant or bleach solution until very wet, and let it soak for at least 5 minutes.
*Use paper towels, a sponge, or a mop to clean up the contaminated area.
*Wear an N95 mask to provide another level of protection.
While deer mice may be mostly a rural problem, other rodents—including rats and house mice—affect urban dwellers. Rats and mice contribute to approximately 55 different diseases, including a diverse range of pathogens from viruses to parasitic worms. Unfortunately, facility managers often choose to deal with rodent infestations by primarily setting out poison (rodenticide) baits. Rodenticides are hazardous and pose a very dangerous threat to children and animals, making them either very sick or causing death if ingested. A significant number of peer-reviewed studies document the toxic nature of rodenticides. Second-generation anticoagulant rodenticides (SGARs) have been found in the tissue of various aquatic and terrestrial organisms, leading researchers and conservationists to increasingly scrutinize the role of toxic pesticide drift from bait stations to streams, forests, and other habitats.
An ecological approach to urban rat management begins by considering the reasons that rats are in an area in the first place. Such an approach would focus on improving the quality of life in low-income areas of degraded housing and other public amenities. Thus, an ecological approach to urban rodent management involves solving social problems as well as scientific problems. It also requires accepting that mice and rat problems can be a symptom of another problem. Rodents in structures are symptoms of other problems because they are always a factor of “upstream determinants” like weak building codes, disrepair resulting in entry points, or inadequate landscaping practices. Municipal rodent problems are also always unique, with different outbreak sources, conditions, and goals, making clear best practices for rat management a function of conditions on the site.
A review outlines a new paradigm in rodent management. It begins with mapping out the rat problem in the region, “to highlight, for example, where rats are considered problematic, who is vulnerable, who is resilient, what policies are in place to address them and do they work better in some areas, and which municipal departments and sectors of the urban environment are affected.” This new approach emphasizes the improvement of overall community health, rather than focusing on rodents as symptoms of a problem that occurs in a vacuum. In doing so, a community may be able to successfully use different intervening actions—such as proper waste disposal, keeping livestock out of water bodies, and alterations to butchering practices.
Beyond Pesticides advises the following: Tell local officials to use good sanitation and management to prevent rodent problems. In the event that your local mayor is not in the system, we invite you to email this message (included below) to them personally.
[Also, see commentary from Beyond Pesticides, January 2026: On Public and Environmental Health and Worldwide Collaboration. You can take action and tell Congress to support and fund international organizations critical to the global health of humans and the biosphere, AND Tell Governors/Lieutenant Governors to join (as well as thank them for joining) the Governors Public Health Alliance and to expand their support for international agencies that protect biodiversity and mitigate the climate crisis (IUCN, IPBES, and IPCC).]
Mayor or Local Official
Recent news concerning the hantavirus highlights the importance of addressing rodent problems with a socio-ecological approach.
Since 1993, people in the Four Corners area of the U.S. Southwest have faced periodic outbreaks of hantavirus. Although the virus is found elsewhere, the ecology of the rural Southwest—including geography, climate, housing patterns, and close human contact with deer mice—produces ideal conditions for the disease to flourish. Understanding this ecology can help prevent hantavirus in humans, as well as other rodent-borne diseases. The problem raises issues of rodent management in our community and ensuring that we adopt practices that offer control, but do not harm human health and the environment.
Hantavirus is mostly carried by wild rodents—unlike the Andes strain infecting people on the cruise ship MV Hondius. People typically become infected by inhaling viral particles from these rodents’ urine, feces, or saliva—for instance, while cleaning a remote cabin infested with wild rodents. Vacuuming or sweeping up areas that may have been contaminated by live or dead rodents is discouraged because the activity releases viral particles into the air.
Instead, community education is needed to ensure that basic protective practices are followed, such as:
*Wear gloves.
*Spray the contaminated area with the disinfectant or bleach solution until very wet, and let it soak for at least 5 minutes.
*Use paper towels, a sponge, or a mop to clean up the contaminated area.
*Wear an N95 mask to provide another level of protection.
While deer mice may be mostly a rural problem, other rodents—including rats and house mice—affect urban dwellers. Rats and mice contribute to approximately 55 different diseases, including a diverse range of pathogens from viruses to parasitic worms. Unfortunately, facility managers often set out poison (rodenticide) baits. Rodenticides are hazardous and pose a dangerous threat to children and animals, possibly resulting in illness or death. A significant number of peer-reviewed studies document the toxic nature of rodenticides. Second-generation anticoagulant rodenticides (SGARs) have been found in various aquatic and terrestrial organisms, leading researchers and conservationists to increasingly scrutinize the role of toxic pesticide drift from bait stations to streams, forests, and other habitats.
An ecological approach to urban rat management begins by considering the reasons that rodents are in an area in the first place. Such an approach would focus on improving the quality of life in low-income areas of degraded housing and other public amenities—thus addressing social problems as well as scientific problems and accepting that rat problems can be a symptom of another problem, such as weak building codes or inadequate landscaping practices. This approach begins by mapping out the rat problem in the region, to highlight where rats are considered problematic, who is vulnerable, who is resilient, what policies are in place to address them, and with what success. Affected municipal departments and sectors of the urban environment need to be identified. This approach emphasizes the improvement of overall community health, rather than focusing on rodents as a problem that occurs in a vacuum. In doing so, a community may be able to successfully use different intervening actions—such as improved building codes, making needed repairs that seal entry points, and proper waste disposal and sanitation practices—to prevent rodent problems.
I urge you to adopt an ecological approach to preventing rodent problems.
Thank you.
All unattributed positions and opinions in this piece are those of Beyond Pesticides.
