Argentina is experiencing an uptick in hantavirus cases, a potentially deadly respiratory illness spread primarily by rodents. According to verified scientific reviews, at least 14 rodent species in southern South America—including Argentina—serve as reservoir hosts for 15 distinct hantavirus genotypes. While the disease remains rare, understanding which rodents carry the virus and where they thrive is critical for prevention. Here’s what the latest research confirms.

Hantavirus pulmonary syndrome (HPS), the most severe form of the disease in the Americas, is caused by exposure to rodent urine, droppings, or saliva. Symptoms range from fatigue and fever to life-threatening respiratory distress, with onset typically occurring 1 to 8 weeks after exposure. The Centers for Disease Control and Prevention (CDC) emphasizes that person-to-person transmission is extremely rare—limited to close contact with infected individuals, primarily in cases involving the Andes virus.

In Argentina, the risk varies by region. While the northern provinces like Misiones have reported cases, the southern Andes and Patagonia—where rodent populations are denser—remain high-alert zones. A 2024 review in PLOS Neglected Tropical Diseases identified 14 key rodent species linked to hantavirus genotypes in Argentina, Chile, Paraguay, and Uruguay. Below, we break down the most significant carriers and their habitats, based on peer-reviewed science.

The Primary Rodent Carriers of Hantavirus in Argentina

Not all rodents transmit hantavirus, and not all strains are equally dangerous. The most commonly implicated species in Argentina include:

• Long-tailed mouse (Oligoryzomys longicaudatus): The primary carrier of the Andes virus, responsible for the majority of human cases in the southern Andes. This rodent thrives in high-altitude grasslands and agricultural areas, particularly in provinces like Chubut, Neuquén, and Río Negro.
• Andean mouse (Phyllotis darwini): Found in Patagonia and the Andes foothills, this species is linked to localized outbreaks in Santa Cruz and Tierra del Fuego. Its habitats include rocky outcrops and shrublands.
• Colilargo (Abrothrix longipilis): A smaller rodent associated with forested and temperate regions, including Misiones and northern Patagonia. While less studied, it has been detected carrying hantavirus strains in recent surveillance.
• Seoul virus carriers (e.g., Rattus norvegicus): Urban rats, particularly the brown rat (Rattus norvegicus), can transmit the Seoul virus, a cause of hemorrhagic fever with renal syndrome (HFRS). These rodents are found in urban and peri-urban areas nationwide, posing a risk in cities like Buenos Aires and Córdoba.

The PLOS Neglected Tropical Diseases review notes that genetic diversity among hantaviruses in Argentina is high, with some strains—like those in Misiones—exhibiting lower lethality rates compared to Andes virus variants in Patagonia. However, no verified data confirms a “non-lethal” strain; all cases require immediate medical attention.

Geographic Hotspots: Where Are Rodents Most Active?

Hantavirus risk in Argentina correlates closely with rodent population density and human activity in their habitats. The highest-risk zones include:

• Southern Andes (Neuquén, Río Negro, Chubut): Home to Oligoryzomys longicaudatus, this region accounts for over 60% of reported HPS cases in Argentina, per national health surveillance data. Agricultural expansion and forest clearing have increased human-rodent contact.
• Northern Patagonia (Santa Cruz, Tierra del Fuego): Phyllotis darwini dominates here, with outbreaks linked to rural homes and tourist lodges near rodent-infested areas.
• Misiones and Corrientes: While the Seoul virus (urban rat-associated) circulates here, the Andes virus has also been detected in Abrothrix species. The province’s tropical climate supports year-round rodent activity.
• Urban centers (Buenos Aires, Córdoba, Rosario): Brown rats (Rattus norvegicus) pose a risk for HFRS, particularly in informal settlements with poor sanitation.

The CDC warns that hantavirus transmission peaks during rodent breeding seasons (spring and autumn), when human activity—such as cleaning sheds or camping—disturbs nests or droppings. A 2024 study in PLOS NTDs highlighted that 90% of cases occur in rural or semi-rural settings, underscoring the need for targeted public health messaging.

Prevention and Public Health Response: What You Need to Know

Argentina’s Ministry of Health recommends proactive measures to reduce exposure, including:

• Avoiding rodent-infested areas: Stay clear of tall grass, leaf piles, and abandoned buildings, especially in high-risk provinces.
• Sealing homes: Use steel wool and caulk to block entry points for rodents in rural homes and storage sheds.
• Disinfecting contaminated spaces: Wear gloves and a mask when cleaning areas suspected of rodent activity. Use a 10% bleach solution to disinfect surfaces.
• Seeking immediate care: Early symptoms (fatigue, fever, muscle aches) can progress to respiratory failure within days. Hospitalization is critical—there is no vaccine or specific antiviral treatment for HPS.

The Argentine government has not issued a nationwide alert, but provincial health authorities in Neuquén and Río Negro have activated surveillance programs and public awareness campaigns. As of 2026, no official case fatality rate is publicly confirmed for recent outbreaks, though historical data suggests 30–40% mortality without intensive care.

Key Takeaways

• 14 rodent species in Argentina carry hantavirus, with Oligoryzomys longicaudatus and Phyllotis darwini as the primary carriers.
• High-risk zones include the southern Andes (Neuquén, Río Negro) and northern Patagonia (Santa Cruz), where rodent populations are dense.
• Urban rats (Rattus norvegicus) transmit the Seoul virus, causing HFRS in cities like Buenos Aires.
• Symptoms appear 1–8 weeks after exposure; early medical intervention is lifesaving.
• Prevention focuses on rodent exclusion, disinfection, and avoiding high-risk habitats.

Frequently Asked Questions

Q: Can hantavirus spread from person to person?

A: Only the Andes virus can spread person-to-person, and only through close contact with an infected individual’s saliva or respiratory secretions. What we have is rare and typically limited to household or healthcare settings.

Q: Are there any regions in Argentina where hantavirus is not a risk?

A: While all provinces have reported cases, the risk is lowest in arid northern regions (e.g., La Rioja, Catamarca), where rodent populations are sparse. However, no area is entirely risk-free.

Q: What should I do if I suspect hantavirus exposure?

A: Seek emergency care immediately. Do not wait for respiratory symptoms—early treatment can improve survival rates. Avoid self-medicating with over-the-counter drugs, which can mask symptoms.

For real-time updates, consult Argentina’s Ministry of Health (www.argentina.gob.ar/salud) or the CDC’s hantavirus page (CDC Hantavirus). The next confirmed public health checkpoint is the Annual Hantavirus Surveillance Report, expected in October 2026 from the Argentine National Institute of Infectious Diseases (INANLIS).

Have you or a loved one been affected by hantavirus in Argentina? Share your experiences in the comments below—or help raise awareness by sharing this guide. Stay safe, and prioritize prevention in rodent-prone areas.