90-Second Read: What is Hantavirus and why were patients brought to Emory Hospital?

The outbreak, linked to multiple infections and several deaths, has raised questions about how Hantavirus spreads and why some patients are being transported to hospitals such as Emory Hospital. ATLANTA, Health officials around the world are continuing to monitor passengers from the MV Hondius cruise ship after a deadly outbreak involving the rare Andes strain of Hantavirus. The outbreak, which has been linked to multiple infections and several deaths, has raised questions about how Hantavirus spreads, how passengers may have become infected and why some patients are being transported to highly specialized hospitals such as Emory University Hospital. The Andes strain connected to the cruise ship outbreak is different because it is the only known Hantavirus capable of spreading from person to person, although experts stress this type of transmission.

PREVIOUS STORY: Hantavirus latest: Americans disembark cruise and head home for quarantine Because Hantavirus has a long incubation period, infected travelers may not have shown symptoms until days or weeks after boarding the ship. The World Health Organization has called it the first known Hantavirus outbreak associated with a cruise ship. Some patients tied to the outbreak are being sent to highly specialized infectious disease centers, including Emory University Hospital, because the hospital operates one of the world's leading containment and treatment units for dangerous infectious diseases. The viruses are typically carried by rodents such as rats and mice, which often do not become sick themselves. As the illness worsens, patients can develop coughing, chest tightness, breathing problems and fluid buildup in the lungs.

Hantavirus is not a single virus but a group of related viruses found around the world. In North and South America, Hantavirus infections can lead to Hantavirus pulmonary syndrome, a severe respiratory illness that affects the lungs and can become life-threatening. Health officials estimate severe cases can carry a fatality rate of roughly 40%. Most Hantavirus infections occur when people inhale virus particles from rodent urine, droppings or saliva that have become airborne. Symptoms often begin with flu-like signs including fever, fatigue, muscle aches, headaches and nausea.

Officials said some passengers had participated in bird-watching trips and visited areas where rodents known to carry the Andes virus were present. Since then, the facility has continued conducting national preparedness exercises and treating patients with serious infectious diseases. The Centers for Disease Control and Prevention says symptoms can appear anywhere from four days to six weeks after exposure. According to the CDC and the World Health Organization, person-to-person spread generally requires prolonged, close contact with a symptomatic patient in enclosed settings. Health officials continue to stress that the overall risk to the general public remains very low.