Hantavirus history and outbreaks
Hantaviruses have shaped public health responses for nearly a century, from Korean War-era hemorrhagic fever among UN troops, to the 1993 emergence of Sin Nombre virus in the Four Corners region, to the 2018-2019 Epuyén person-to-person ANDV outbreak, to the 2026 MV Hondius cruise-ship event.
Pre-history and Korean War
Chinese physicians described an illness consistent with HFRS as early as the 10th century, and Russian and Japanese reports from the 1930s in Manchuria documented thousands of cases. Western awareness exploded during the Korean War (1950-1953), when more than 3,000 UN soldiers — mainly American — developed what was called 'Korean hemorrhagic fever' along the 38th parallel. Identification of the causative agent had to wait until 1976, when Karl Johnson and Ho-Wang Lee isolated Hantaan virus from the striped field mouse (Apodemus agrarius) near the Hantan River.
Four Corners 1993
In May 1993, a cluster of previously healthy young adults in the Four Corners region of the southwestern United States died of acute respiratory failure within days of a flu-like illness. The Navajo (Diné) community recognized the pattern and connected it to a pinyon-mast year and rodent population boom. Within weeks, CDC and university investigators identified a novel hantavirus — initially called Muerto Canyon virus and later renamed Sin Nombre virus ('no-name virus') — with the deer mouse (Peromyscus maniculatus) as its reservoir. The outbreak revealed an entirely new clinical syndrome, HPS, and re-cast hantaviruses as a New World threat.
Andes virus emerges
Andes virus was isolated in 1995 from cases in southern Argentina. The El Bolsón cluster of 1996 — 20 cases including a physician treating index patients — was the first to suggest person-to-person transmission. Genomic studies in subsequent years confirmed the linkage. Outbreaks in Los Antiguos (Argentina, 2003), Bariloche, and across Chilean Patagonia established ANDV as a regional priority pathogen.
Epuyén 2018-2019
Between November 2018 and March 2019, an outbreak in Epuyén, Argentina (Chubut province) infected at least 34 people and killed 11. Genomic and contact tracing showed up to four generations of person-to-person transmission, with an index case linked to a birthday gathering. Argentine authorities imposed targeted quarantine — among the first uses of focused public-health containment for hantavirus — and the outbreak was contained within months. Epuyén became the template for ANDV response planning, including the protocols later activated for MV Hondius.
MV Hondius 2026
In late March 2026, an outbreak emerged on the expedition cruise MV Hondius during a South Atlantic voyage. By mid-April more than 60 confirmed and suspected cases had been linked to the vessel and the subsequent St Helena evacuation, with cases tracked in Argentina, Chile, the Netherlands, Switzerland, Spain, Germany, the United Kingdom, South Africa and Singapore — the most geographically dispersed hantavirus event ever recorded. WHO Disease Outbreak News covered the event in three updates between April and June 2026.
- •Hantaan virus identified 1976 by Karl Johnson and Ho-Wang Lee
- •Sin Nombre virus identified 1993 after Four Corners outbreak
- •Andes virus identified 1995, person-to-person confirmed 1996
- •Epuyén 2018-2019: 34 cases, 4 generations of transmission
- •MV Hondius 2026: most geographically dispersed hantavirus event