Four Californians exposed to the deadly Hantavirus outbreak linked to a Dutch cruise ship are being monitored by health officials — including one Bay Area resident who was aboard the vessel before the illness was detected.

The California Department of Public Health said on Monday it is coordinating with the CDC and local health officials after three California residents were identified as passengers on the MV Hondius, where an outbreak of Andes Hantavirus has killed three people.

A fourth Californian was exposed while sitting near a returning cruise passenger on an international flight, CDPH said.

State officials stressed the risk to the public remains “extremely low.”

Two of the Californians have already returned home and are being monitored by local public health officials, according to CDPH.

The other two were transported by federal authorities to a secure medical facility in Nebraska and are expected to return to California once health assessments are completed and safety arrangements are in place.

“We understand public concern about this unusual outbreak,” Dr. Erica Pan, California’s state public health officer and CDPH director, said in a statement.

“Decades of experience in South America have shown that this Andes Hantavirus rarely spreads between people. We continue to work with federal health officials to monitor the health of potentially exposed individuals and prepare for our Californians to come home.”

One of the exposed Californians is a Santa Clara County resident who has been aboard the MV Hondius but got off the ship before the outbreak was detected, NBC Bay Area reported.

The South Bay Area resident is at home, feeling well and showing no symptoms, according to Santa Clara County health officials. The person is being closely monitored and has had their activities restricted under CDC recommendations, the outlet reported.

“I want to reassure the public that the risk of contracting Andes Hantavirus in Santa Clara County remains extremely low,” Dr. Sarah Rudman, Santa Clara County’s public health officer, said, according to NBC Bay Area.

Another exposed Californian is a Sacramento County resident who was not on the cruise ship but was exposed on an international flight, FOX40 reported.

---

Here’s the latest on the deadly hantavirus outbreak on the Dutch cruise ship:

• Contagious hantavirus strain may stay in human sperm for six years — and turn into an STI
• CDC monitoring 41 people for hantavirus after deadly cruise infection
• 6 passengers from hantavirus-hit ship arrive in Australia for 3-week quarantine
• How prepared is the US for another pandemic? New rankings show how we compare to other countries

---

That resident is also not showing symptoms and is under home quarantine while being monitored by local, state and federal agencies, Sacramento County Public Health officials told the outlet.

“The risk to the public remains very low, but we are taking this situation seriously and following all recommended monitoring protocols out of an abundance of caution,” Dr. Olivia Kasirye, Sacramento County’s public health officer, said in a statement obtained by FOX40.

“At this time, the individual is not sick and has not been diagnosed with Hantavirus.”

The MV Hondius was carrying 147 people from 23 countries — 86 passengers and 61 crew members — when the outbreak emerged.

The ship departed Ushuaia, Argentina, on April 1 and traveled across the South Atlantic, which stops including Antartica, South Georgia Island, Tristan de Cunha, Saint Helena and Ascension Island.

The World Health Organization was notified May 2 of severe respiratory illness among passengers and crew, according to NBC Bay Area.

The remaining passengers on the cruise ship disembarked Monday and boarded flights to more than 20 countries to begin quarantine.

Hantaviruses are spread through the urine, droppings and saliva of wild rodents, CDPH said.

The Andes strain identified in the cruise ship outbreak is found in the southern Andes region of Argentina and Chile and has been associated with rare person-to-person spread after close, prolonged contact with an infected person, according to CDPH.

That is different from the Sin Nombre Hantavirus, which is native to California and North America and has not been linked to person-to-person transmission, state officials said.

From 1980 to 2025, 99 California residents have been diagnosed with Sin Nombre Hantavirus infection, according to CDPH.

Hantavirus Pulmonary Syndrome is a rare but severe respiratory illness that can start with flu-like symptoms, sometimes including stomach problems, before rapidly progressing to life-threatening respiratory distress, the state said.

The fatality rate is about 30% to 40%, and there is no antiviral treatment for Hantavirus, according to CDPH. Severe cases usually require aggressive critical care.

Pan said during a Monday media briefing that all four exposed Californians are currently asymptomatic, NBC Bay Area reported.

CDPH said its monitoring protocols include daily temperature checks, symptom checks and directions for exposed people to modify their activities.

The state also said its Viral Rickettsial Disease laboratory was the only public health lab in the US with a validated diagnostic Hantavirus PCR test before the outbreak response — meaning California can test exposed residents in-state if they develop symptoms.

CDPH said it is also working with hospitals that could care for potential Hantavirus cases and has issued clinical health advisories to doctors.

“The risk to the public remains extremely low,” the department said.

---

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