California is now included as a part of a frantic global search to locate passengers who left a cruise ship linked to a deadly outbreak of hantavirus.

Three passengers — including a Dutch couple and a German national — died and at least eight others fell ill aboard the MV Hondius after contracting the virus during an expedition run by Netherlands-based Oceanwide Expeditions.

Nearly two weeks after the first death onboard, more than two dozen passengers had already disembarked the ship without full contact tracing, according to officials.

Those individuals are now being actively tracked as health agencies work to determine whether any secondary spread has occurred.

State health officials confirmed residents of California were aboard the vessel and are being monitored as a precaution.

None of the Californians have tested positive or developed symptoms, but they remain under observation as part of ongoing surveillance efforts.

Investigators believe the outbreak may have originated before the cruise, with Argentine health authorities focusing on a southern region where a Dutch couple reportedly contracted the virus during a bird-watching trip before boarding the ship.

The World Health Organization says the overall public risk remains low, noting that hantavirus is usually transmitted through inhalation of particles from infected rodent droppings, and is not easily spread between people.

However, concern has increased because the Andes strain found in South America is the only variant known to allow limited person-to-person transmission.

In the United States, hantavirus remains rare but highly dangerous.

---

Download The California Post App, follow us on social, and subscribe to our newsletters

Since the Centers for Disease Control and Prevention began tracking cases in 1993, more than 300 people have died. There were 890 confirmed cases nationwide between 1993 and 2023, with a mortality rate of more than 34%.

The most affected states have included New Mexico, Colorado, Arizona, California, and Washington.

California has recorded about 80 to 90 cases in history, with 24 deaths reported. The state averages about three cases per year. Most infections in the state are linked to rural and mountainous regions such as the Sierra Nevada, where deer mice carry the Sin Nombre virus.

That strain accounts for most US infections and is not known to spread between people, unlike the suspected South American variant now under investigation in the cruise outbreak.

As authorities continue tracing passengers who returned home across multiple continents, including the US, the priority remains identifying any new infections and determining whether the virus spread beyond the ship.

Officials say there is still no evidence of widespread transmission, even as the international search effort continues.