causes Lassa fever<\/a> in parts of Africa \u2014 are another. These viruses can trigger severe hemorrhagic fevers with mortality rates ranging from 5 to 30 percent. <\/p>\n\n\n\nAmong the arenaviruses that have caused sporadic outbreaks across South America are Guanarito virus, Junin virus and Machupo virus. There are no approved treatments. A vaccine for Junin virus that may also provide some protection against Machupo virus is licensed in Argentina.<\/p>\n\n\n\n
Farmworkers working in areas with infected rodents are typically at highest risk, Kulkarni says. But as Earth\u2019s climate changes, the critters could move to new areas, bringing the viruses with them. \u201cIf there is going to be a high-impact outbreak of arenaviruses,\u201d Kulkarni says, \u201cthese might be the candidates.\u201d <\/p>\n\n\n\n
Kulkarni and colleagues ran computer simulations incorporating habitat suitability for six rodent species known to carry one of the three viruses. The calculations also took future climate projections and population density into account. The team found that the risk of viral transmission from rodents to people goes up over the next 20 years in parts of the continent that aren\u2019t currently at risk.<\/p>\n\n\n\n
Guanarito virus, for instance, is currently found in central Venezuela. But by 2060, the virus could spread to parts of Colombia, Guyana, Suriname and Brazil. Junin virus risk could move from grasslands in Argentina to other parts of the country as well as Paraguay and Bolivia. And Machupo virus, currently found in Bolivia, could in the future also infect people in Brazil, Paraguay and Peru. <\/p>\n\n\n\n
The resulting risk maps \u201cset the stage,\u201d says Greg Glass, a disease ecologist at the University of Florida in Gainesville, who was not involved with the work. \u201cIt allows folks going forward to use these maps to set up studies to go see if these species are there or not.\u201d <\/p>\n\n\n\n
For Glass, verifying the current maps should be the next step. It\u2019s possible the simulations suggest circulation in regions where rodents aren\u2019t truly carrying the viruses. But if the simulations \u201csay it shouldn\u2019t be there, but you find it \u2026 that\u2019s a bigger mistake\u201d that could cost lives, he says.<\/p>\n\n\n\n
Temperature shifts and changes in precipitation were among the climate factors driving shifts in rodent populations in the simulations. Human activities such as agriculture and urbanization also played a role. But the simulations focused on long-term changes, Kulkarni says. \u201cWhat we would really like to do is look at short-term changes in weather, short-term changes in certain climate disruptions and how that affects risk from week to week or month to month.\u201d<\/p>\n\n\n\n
Some changes could already be happening. Hantavirus cases are on the rise in Argentina, said Carlos del Rio, a virologist and infectious diseases physician at Emory University in Atlanta, during a May 7 news briefing<\/a>. \u201cThe main cause of that is climate change. Argentina is becoming more tropical.\u201d <\/p>\n\n\n\nSome of the rodents included in the study can also transmit hantaviruses, Kulkarni says. The yellow pygmy rice rat (Oligoryzomys flavescens<\/em>), for instance, transmits not only Junin virus but also some hantavirus strains. Although the yellow pygmy rice rat is not a known reservoir of the Andes hantavirus strain that is responsible for the cruise ship outbreak, it\u2019s possible that other rodents and pathogens will also expand their ranges as the climate changes.<\/p>\n\n\n\n\u201cClimate change is a reality,\u201d del Rio said. \u201cAnd it has a significant impact in infectious diseases.\u201d <\/p>","sn_app_related":[3170780,3170578,3170542,3170587,3170525,3170383,3170418,3170271],"sn_featured_video":null,"sn_mobile_render_webview":false,"sn_noa_audio":null,"parsely":{"version":"1.1.0","canonical_url":"https:\/\/sciencenews.org\/article\/rodent-arenaviruses-hantavirus-climate","smart_links":{"inbound":0,"outbound":0},"traffic_boost_suggestions_count":0,"meta":{"@context":"https:\/\/schema.org","@type":"NewsArticle","headline":"Some South American rodent-borne viruses may spread as climate warms","url":"http:\/\/www.sciencenews.org\/article\/rodent-arenaviruses-hantavirus-climate","mainEntityOfPage":{"@type":"WebPage","@id":"http:\/\/www.sciencenews.org\/article\/rodent-arenaviruses-hantavirus-climate"},"thumbnailUrl":"https:\/\/www.sciencenews.org\/wp-content\/uploads\/sites\/2\/2026\/05\/050826_EGJ_arenavirus_main.jpg?w=330","image":{"@type":"ImageObject","url":"https:\/\/www.sciencenews.org\/wp-content\/uploads\/sites\/2\/2026\/05\/050826_EGJ_arenavirus_main.jpg"},"articleSection":"Uncategorized","author":[{"@type":"Person","name":"Erin Garcia de Jes\u00fas"}],"creator":["Erin Garcia de Jes\u00fas"],"publisher":{"@type":"Organization","name":"Science News","logo":"https:\/\/www.sciencenews.org\/wp-content\/uploads\/sites\/2\/2025\/01\/cropped-favicon.jpg"},"keywords":["ash","on trend","science in the news"],"dateCreated":"2026-05-11T15:30:00Z","datePublished":"2026-05-11T15:30:00Z","dateModified":"2026-05-11T15:30:00Z"},"rendered":"