𝗣𝘂𝗯𝗹𝗶𝗰 𝗛𝗲𝗮𝗹𝘁𝗵 𝗔𝗹𝗲𝗿𝘁𝘀 𝗥𝗲𝗽𝗼𝗿𝘁: On April 27, 2026, a man (later classified as Patient 3 in the outbreak) was medically evacuated to Ascension Island from the Dutch-flagged expedition cruise ship 𝘔𝘝 𝘏𝘰𝘯𝘥𝘪𝘶𝘴; he had severe acute respiratory infection (SARI) and reported shortness of breath and fever that had begun on April 21. He had signs of pneumonia, although findings on chest radiography were unremarkable. While he was on Ascension Island, his condition worsened, and he was transferred to Johannesburg, South Africa, for ventilator support and intensive care. He was in shock and had acute respiratory distress syndrome; findings on chest radiography were consistent with atypical pneumonia. The differential diagnosis in this clinical context is very broad and includes atypical pneumonias, bacterial or fungal sepsis, and vectorborne diseases such as malaria or dengue. The diagnostic evaluation, including respiratory pathogen panels, malaria smear and antigen, fungal biomarkers, blood cultures, and legionella urinary antigen, was unrevealing. On May 2, the cruise ship had a total of 147 persons on board, including 88 passengers and 59 crew members, from 23 countries. As of May 13, 2026, a total of 10 cases had been identified (an 11th was subsequently reclassified as not a case), including 3 resulting in death (seen in figure). However, because not everyone on board was tested, 3 deaths among 10 cases may represent an overestimation of the case fatality ratio. All cases to date have been among passengers or crew on board the ship. Beyond the first 3 cases, 7 additional confirmed or probable cases have been identified. A German national (Patient 4) died from a SARI on May 2, and later testing in the Netherlands confirmed Andes virus (ANDV). Two crew members — the doctor on the ship (Patient 5) and an expedition guide (Patient 6) — were medically evacuated to the Netherlands, tested positive by PCR and sequencing for ANDV on May 7 and 8, respectively, and were in stable condition at the time of this report. Read “Andes Hantavirus Outbreak on a Cruise Ship, 2026,” which includes clinical details, case timeline, genetic sequencing of the virus, and unresolved transmission questions, by the Andes Virus Outbreak Working Group: nej.md/4uQDeMQ