How Wet Weather in Argentina Helped Fuel the Cruise Ship Hantavirus Outbreak
How Wet Weather in Argentina Helped Fuel the Cruise Ship Hantavirus Outbreak
阿根廷的潮湿天气如何助长了游轮汉坦病毒的爆发
The hantavirus outbreak aboard the MV Hondius cruise ship has created a global public health crisis. But the driver of it is a rodent that weighs about an ounce, and climate shifts this year that have helped increase the odds of transmission. MV Hondius号游轮上的汉坦病毒爆发引发了一场全球公共卫生危机。但其背后的推手是一种体重仅约一盎司（约28克）的啮齿动物，以及今年气候的变化，这些因素共同增加了病毒传播的几率。
Across the Southern Cone, researchers have long associated wetter years with explosive rodent population booms—known locally as ratadas—that can amplify hantavirus transmission. This year’s boom reflects a broader pattern of disease outbreaks shaped by climate change, environmental disruption, and a hyperconnected world. 在南锥体地区（Southern Cone），研究人员长期以来一直将潮湿年份与啮齿动物数量的爆发式增长联系在一起——当地称之为“ratadas”——这种现象会加剧汉坦病毒的传播。今年的爆发反映了一种更广泛的疾病流行模式，即由气候变化、环境破坏和高度互联的世界共同塑造的模式。
“These are emerging diseases because the distribution of both the reservoirs and the viruses is expanding,” says Karina Hodara, a researcher at the Faculty of Agronomy at the University of Buenos Aires who studies hantavirus ecology. “Humans travel across continents in a matter of hours.” “这些属于新兴疾病，因为宿主和病毒的分布范围都在扩大，”布宜诺斯艾利斯大学农学院研究汉坦病毒生态学的研究员卡琳娜·霍达拉（Karina Hodara）表示，“人类在几小时内就能跨越各大洲。”
The long-tailed pygmy rice rat is the common name for several species that live in Chile and Argentina that can harbor hantavirus. Each species is associated with different hantaviruses depending on geography. 长尾侏儒稻鼠（long-tailed pygmy rice rat）是生活在智利和阿根廷、且能携带汉坦病毒的几种物种的统称。根据地理位置的不同，每个物种都与不同的汉坦病毒相关联。
It’s still unclear where the first passengers that got sick with the Andes virus contracted it. But the Patagonian long-tailed pygmy rice rat (Oligoryzomys longicaudatus), which inhabits southern Argentina and the woods and shrublands in Chile and weighs about one ounce, is the main reservoir of the only known hantavirus capable of spreading from rodents to humans and between humans. This person-to-person transmission “is precisely what makes outbreaks possible,” adds Raúl González Ittig, an expert in population genetics and evolution at the National University of Córdoba. 目前尚不清楚首批感染安第斯病毒（Andes virus）的乘客是在哪里感染的。但栖息于阿根廷南部以及智利森林和灌木丛中、体重约一盎司的巴塔哥尼亚长尾侏儒稻鼠（Oligoryzomys longicaudatus），是目前已知唯一能实现从啮齿动物传给人、以及人与人之间传播的汉坦病毒的主要宿主。科尔多瓦国立大学的群体遗传学与进化专家劳尔·冈萨雷斯·伊蒂格（Raúl González Ittig）补充说，这种人与人之间的传播“正是导致疫情爆发的原因”。
But other rodents, including the Pampas long-tailed pygmy rice rat (Oligoryzomys flavescens), can transmit the virus to humans. The virus’s spread is driven in part by changing ecological conditions. When food becomes abundant—following events such as the mass flowering of Patagonian bamboo (Chusquea culeou) or periods of increased fruit production from shrubs such as rosehip and blackberry—rodent populations can expand rapidly. “They eat without limits,” Hodara says. “And then they begin reproducing very quickly.” 但其他啮齿动物，包括潘帕斯长尾侏儒稻鼠（Oligoryzomys flavescens），也能将病毒传播给人类。病毒的传播在一定程度上是由生态条件的变化所驱动的。当食物变得充足时——例如在巴塔哥尼亚竹（Chusquea culeou）大规模开花，或蔷薇果和黑莓等灌木果实产量增加之后——啮齿动物的数量就会迅速膨胀。“它们无节制地进食，”霍达拉说，“然后开始非常迅速地繁殖。”
As more rodents compete more intensely for territory, food, and reproductive access, aggressive encounters between males increase. That, in turn, can increase transmission of the virus through bites or saliva. Once infected, rodents shed the virus into the environment through urine, feces, and saliva. 随着越来越多的啮齿动物为领地、食物和交配权展开更激烈的竞争，雄性之间的攻击性行为也会增加。这反过来又会通过咬伤或唾液增加病毒的传播。一旦感染，啮齿动物就会通过尿液、粪便和唾液将病毒排入环境中。
“Long-tailed pygmy rice rats are climbers and can move more than 2 meters high in trees. That has both positive and negative effects,” explains Isabel Gómez Villafañe, a researcher at the Institute of Ecology, Genetics and Evolution at the University of Buenos Aires. On one hand, contaminated urine or feces deposited higher up are more exposed to ultraviolet radiation, which deactivates the virus. On the other hand, in enclosed environments—such as sheds, cabins, or houses—the virus may persist longer. And as people move through these landscapes, especially during warmer months, contact with contaminated surfaces becomes more likely. “长尾侏儒稻鼠善于攀爬，能在树上移动超过2米的高度。这既有积极影响也有消极影响，”布宜诺斯艾利斯大学生态、遗传与进化研究所的研究员伊莎贝尔·戈麦斯·维拉法涅（Isabel Gómez Villafañe）解释道。一方面，沉积在高处的受污染尿液或粪便更容易受到紫外线照射，从而使病毒失活。另一方面，在封闭的环境中——如棚屋、小屋或住宅——病毒可能会存活更长时间。随着人们在这些环境中活动，特别是在温暖的月份，接触受污染表面的可能性就会增加。
Climate variability is one of the main factors shaping the population dynamics of Oligoryzomys species. During dry years, there’s less food available for rodents, which can lower the population, while the opposite is true in wetter years, upping the odds for more viral transmission. 气候变化是影响稻鼠属（Oligoryzomys）种群动态的主要因素之一。在干旱年份，啮齿动物的食物来源减少，这会降低其种群数量；而在潮湿年份则相反，这增加了病毒传播的几率。
According to González Ittig, this is the factor that best explains the increase in hantavirus cases recorded since last June. 据冈萨雷斯·伊蒂格称，这是解释自去年6月以来汉坦病毒病例增加的最主要因素。
Health officials have reported 101 confirmed cases, most concentrated in central Argentina and associated with the Lechiguanas strain of the virus transmitted by Oligoryzomys flavescens—double the amount of the previous 12-month period. 卫生官员已报告了101例确诊病例，大部分集中在阿根廷中部，并与由潘帕斯长尾侏儒稻鼠传播的Lechiguanas病毒株有关——这一数字是此前12个月期间的两倍。
“We had been coming from years of intense drought, and then in 2025 a wetter cycle began with the arrival of El Niño,” González Ittig says. Central Argentina saw above-average rainfall, according to the nation’s weather service, after years of drought. Patagonia, however, experienced a more uneven pattern, with wetter conditions in some Andean areas but persistent precipitation deficits elsewhere. Researchers say those shifts likely boosted vegetation growth and expanded food availability for rodents. “我们经历了多年的严重干旱，随后在2025年，随着厄尔尼诺现象的到来，一个更潮湿的周期开始了，”冈萨雷斯·伊蒂格说。据阿根廷国家气象局称，阿根廷中部在经历了多年干旱后，降雨量高于平均水平。然而，巴塔哥尼亚的情况则更为不均衡，一些安第斯地区变得更加潮湿，而其他地区则持续降水不足。研究人员表示，这些变化很可能促进了植被生长，并增加了啮齿动物的食物供应。
Scientists say these changes are part of a broader climate trend already reshaping rainfall patterns across the Southern Cone, making some regions wetter and others drier. In the Pampas region—including central Argentina and parts of Uruguay—rising humidity, milder winters, longer warm seasons, and heavier rainfall are creating conditions that favor rodent survival, reproduction, and the spread of hantavirus. 科学家们表示，这些变化是更广泛气候趋势的一部分，该趋势正在重塑整个南锥体的降雨模式，使一些地区变得更潮湿，而另一些地区则更干燥。在潘帕斯地区——包括阿根廷中部和乌拉圭部分地区——湿度上升、冬季变暖、暖季延长以及降雨量增加，正在创造有利于啮齿动物生存、繁殖和汉坦病毒传播的条件。
At the same time, the geography of risk also appears to be changing. In recent years, cases have begun to emerge in new parts of Argentina, including some fatal infections. Researchers believe this may reflect a broader reconfiguration of hantavirus risk, linked to environmental transformation and expanding human activity. 与此同时，风险的地理分布似乎也在发生变化。近年来，阿根廷的一些新地区开始出现病例，包括一些致命感染。研究人员认为，这可能反映了汉坦病毒风险的更广泛重组，这与环境转型和人类活动的扩张有关。
“We are constantly invading natural environments,” Hodara says. “We move into forests and mountains, lakes and wetlands, we build gated communities. And that increases the chances of contact for us.” “我们不断地侵入自然环境，”霍达拉说，“我们搬进森林、山区、湖泊和湿地，我们建造封闭式社区。这增加了我们与它们接触的机会。”
Land-use change and the rodents’ remarkable adaptability may also be playing a role. Scientists are increasingly finding Oligoryzomys rodents in landscapes heavily altered by agriculture and human activity. “I captured Oligoryzomys right in the middle of a wheat field in Córdoba, a province in central Argentina,” González Ittig says. “These rodents tolerate modifications of the natural environment surprisingly well, and that may explain why cases are appearing outside traditional areas.” 土地利用的变化和啮齿动物惊人的适应能力也可能在其中发挥了作用。科学家们越来越多地在受农业和人类活动严重改变的景观中发现稻鼠属啮齿动物。“我在阿根廷中部科尔多瓦省的一个麦田中央捕获过稻鼠，”冈萨雷斯·伊蒂格说，“这些啮齿动物对自然环境改变的耐受力出奇地好，这或许能解释为什么病例会出现在传统区域之外。”
Gómez Villafañe also notes that researchers in recent years have identified hantavirus variants in Argentina that had previously only been documented in neighboring countries, including the Alto Paraguay strain, associated not with Oligoryzomys rodents but with the Chacoan marsh rat (Holo… 戈麦斯·维拉法涅还指出，研究人员近年来在阿根廷发现了以前仅在邻国记录过的汉坦病毒变种，包括Alto Paraguay病毒株，它并非与稻鼠属啮齿动物有关，而是与查科沼泽鼠（Holo…有关。