90-Second Read: CDC Alerts Clinicians About Potential for Imported Hantavirus Cases

About 30 passengers disembarked the ship on April 24, returning to their home countries, including several Americans. From 1993 through 2023, there have been a total of 890 lab-confirmed cases of Hantavirus in the U.S., with a case fatality rate of 35%. As of May 8, WHO reported six confirmed cases, two suspected cases, and three deaths. Several state health departments -- including Arizona, California, Georgia, Texas, and Virgina -- confirmed to MedPage Today that they are monitoring individuals in their respective states.

People with Hantavirus disease are generally only infectious while symptomatic, the agency said. Andes virus is the only type of Hantavirus that has documented human-to-human transmission. The HAN provided a disease timeline, beginning with the May 2 notification to the World Health Organization (WHO) of a cluster of severe acute respiratory illness among passengers and crew of the ship. In addition, the virus may not be accurately detected in body secretions and excretions within the first 72 hours of symptom onset, so testing should be repeated after that window, the agency warned.

The CDC said that symptoms typically appear 4 to 42 days after exposure -- though some reports have suggested up to 8 weeks -- and early symptoms can include fever, headache, muscle aches, nausea, and fatigue. About half of patients experience headaches, dizziness, chills, and gastrointestinal symptoms including nausea, vomiting, diarrhea and abdominal pain, the agency said. Late symptoms appear about 4 to 10 days after the initial phase of the illness and can include coughing, shortness of breath, and chest tightness. The agency also recommended that healthcare providers follow its guidance for Andes virus infection control in healthcare settings when patients are suspected to have the disease.

Maryland also announced it is monitoring two people who were on that flight. A Dutch flight attendant from that flight who had symptoms and was being treated recently tested negative for the virus. It recommends placing them in an airborne infection isolation room, as well as use of a gown, gloves, eye protection, and an N95 or higher-level respirator when entering the patient's room.