A spray developed in one crisis, now tested against another
En los laboratorios del Instituto Carlos Malbrán de Buenos Aires, científicos argentinos están redirigiendo una herramienta nacida de la pandemia hacia una amenaza más antigua y silenciosa: el hantavirus. El spray nasal con carragenina, derivada de algas rojas, ya demostró eficacia contra resfríos, influenza y COVID-19, y ahora se somete a pruebas clínicas con trabajadores de salud expuestos al virus. En un mundo donde las enfermedades zoonóticas siguen cruzando fronteras —como lo demostró el brote en un crucero holandés— este trabajo encarna la capacidad humana de convertir las lecciones de una crisis en escudo para la siguiente.
- El hantavirus Andes, capaz de transmitirse entre personas, generó alarma internacional al infectar pasajeros de múltiples nacionalidades a bordo del crucero MV Hondius.
- Los trabajadores de salud que atienden pacientes con hantavirus enfrentan una exposición real y documentada, sin más defensa que el cuidado y la distancia.
- El equipo del Laboratorio Nacional de Referencia para Hantavirus lleva desde 2020 escalando pruebas: de tubos de ensayo a ensayos clínicos con personas en riesgo directo.
- La carragenina mostró capacidad para interferir con la replicación viral en laboratorio y resultados prometedores en el entorno clínico, aunque las pruebas específicas contra hantavirus aún están en curso.
- Si el spray funciona, transformaría la prevención: de medidas de higiene difíciles de sostener a una herramienta simple, accesible y desplegable a gran escala en comunidades vulnerables.
En un laboratorio de Buenos Aires, un equipo de científicos argentinos trabaja con una pregunta que podría cambiar la prevención de una enfermedad que lleva décadas acechando la región: ¿puede un spray nasal proteger contra el hantavirus? La herramienta que están probando no surgió de esta crisis, sino de la anterior. Durante el caos inicial de la pandemia de COVID-19, investigadores formularon un spray con carragenina —un compuesto extraído de algas rojas— que ya había demostrado eficacia contra resfríos, influenza y el coronavirus. La pregunta ahora es si esa misma defensa puede sostenerse frente a un virus que opera con una lógica molecular completamente distinta.
El trabajo se desarrolla en el Laboratorio Nacional de Referencia para Hantavirus, dentro del Instituto Nacional de Enfermedades Infecciosas Carlos Malbrán. Comenzó en 2020 con pruebas en tubos de ensayo y placas de Petri, observando si la carragenina podía interferir con la replicación del virus. Pudo. Ese resultado abrió la puerta a la siguiente etapa: ensayos con enfermeras y trabajadores de salud cuya exposición al hantavirus es real y cotidiana. Allí también el spray mostró resultados prometedores.
Lo que le da urgencia particular a esta investigación es la naturaleza del hantavirus Andes. A diferencia de otras variantes, puede transmitirse de persona a persona, una capacidad que quedó en evidencia cuando infectó a pasajeros de múltiples nacionalidades a bordo del crucero holandés MV Hondius. Esa posibilidad de propagación respiratoria convierte al Andes en una amenaza de otra escala.
Hoy, la única defensa real contra el hantavirus es la evitación del contacto con roedores y una higiene rigurosa —medidas difíciles de sostener en comunidades rurales o en entornos clínicos de alta exposición. Un spray nasal sería más simple, más accesible y potencialmente desplegable a gran escala. La investigación aún está en sus primeras fases, pero su trayectoria es clara: de una pandemia a la siguiente, del laboratorio a la práctica clínica.
In a laboratory in Buenos Aires, a team of Argentine scientists is testing a nasal spray that might do something unexpected: protect people from hantavirus, a disease spread by wild rodents that gained sudden international attention when it infected passengers aboard a Dutch cruise ship. The spray itself is not new. It was developed during the COVID-19 pandemic, formulated with carrageenan, a compound derived from red algae that had already shown it could ward off colds, influenza, and the coronavirus itself. Now researchers are asking whether it might work against a virus that kills through a different route entirely.
The work is happening at the National Reference Laboratory for Hantavirus, housed within the Molecular Biology Service at Argentina's National Institute of Infectious Diseases, known as the Carlos Malbrán Institute. It is methodical work, the kind that does not make headlines until it does. The team began this particular project in 2020, during the pandemic's early chaos, when the world was desperate for any tool that might slow viral transmission. They started with laboratory tests in petri dishes and test tubes, watching to see whether carrageenan could interfere with the virus's ability to replicate. It could. That small success gave them permission to move forward.
Hantavirus itself is a zoonotic disease, meaning it jumps from animals to humans. Wild rodents carry it in their feces, urine, and saliva. Most of the time, infection happens when a person breathes in contaminated dust or comes into contact with infected material. But the Andes variant—the strain that caused the outbreak aboard the MV Hondius, a Dutch-flagged cruise ship—is different. It can spread from one human to another. That capacity for person-to-person transmission is what made the cruise ship outbreak so alarming, infecting passengers of multiple nationalities and raising the specter of a virus that could move through a population the way respiratory viruses do.
Andrea Vanesa Dugour, one of the researchers leading the effort, described the progression to a news agency. The team had moved beyond the petri dish phase. They had begun testing the spray with healthcare workers and nurses—people whose jobs put them in direct contact with hantavirus patients. These were not theoretical trials. They were working with people whose exposure was real and documented. The spray showed promise in that setting too, suggesting that it might actually protect the people most at risk.
Now the work has entered a new phase. The scientists are conducting the tests needed to determine whether carrageenan can prevent hantavirus infection specifically. It is a logical next step, but also a necessary one. A compound that works against one virus does not automatically work against another. The molecular mechanisms are different. The way the virus enters cells, replicates, and spreads through the body follows its own logic. The researchers are asking whether carrageenan's defenses hold up against this particular threat.
What makes this work significant is not just the potential of the spray itself, but what it represents: a tool developed in response to one pandemic being repurposed for a disease that has haunted Argentina and neighboring countries for decades. Hantavirus outbreaks are not new, but they are unpredictable and often severe. The Andes variant, in particular, carries a high mortality rate. If a nasal spray could reduce transmission, especially among healthcare workers and in communities where rodent contact is common, it would change the calculus of prevention. Right now, the only real defense is avoidance and careful hygiene. A spray would be simpler, more accessible, and deployable at scale. The research is still in its early stages, but the direction is clear: from laboratory to clinical use, from one crisis to the next.
Citas Notables
We started with laboratory tests to evaluate it and saw that it inhibits the virus's ability to replicate, which allowed us to move forward toward clinical trials with healthcare workers and nurses exposed to the virus.— Andrea Vanesa Dugour, researcher at the Carlos Malbrán Institute
La Conversación del Hearth Otra perspectiva de la historia
Why does a spray developed for COVID-19 matter for hantavirus? They seem like completely different problems.
They are different viruses, yes, but carrageenan works on a basic level—it seems to interfere with how viruses attach to and enter cells. That mechanism doesn't care which virus it is. The researchers tested it in the lab and saw it actually inhibit the virus's ability to replicate. That's the proof of concept.
And the cruise ship outbreak—that's what made people suddenly care about hantavirus?
Exactly. Hantavirus had been circulating in rodent populations for a long time, but the Andes variant can spread between humans. When it got onto that ship, it moved through the passenger population like any respiratory disease would. That's when the world noticed.
So healthcare workers are already testing this spray?
They are. The researchers moved from lab tests to trials with nurses and doctors who are actually exposed to hantavirus patients. That's a big step—it means they're confident enough to put it in front of real people in real conditions.
What happens if it works?
Then you have a preventive tool that's simple to use, easy to distribute, and doesn't require people to avoid their jobs or their communities. For a disease with no vaccine and no cure, that changes everything.
And if it doesn't?
Then they've learned something about how carrageenan interacts with this particular virus, and they keep looking for other approaches. But the fact that it worked in the lab and showed promise with healthcare workers suggests they're on to something real.