At least five Americans on both US coasts are being monitored for hantavirus symptoms, even though they never set foot on board the ill-fated MV Hondius cruise ship.

Two New Jersey residents, two Marylanders, and one Californian are in isolation under the strict supervision of health department officials after they all took international flights that included passengers from the virus-stricken cruise.

None has exhibited any symptoms, and it’s unclear if they contracted the virus.

Seventeen Americans were aboard the Dutch expedition cruise ship at the center of the hantavirus outbreak. The rare Andes strain of hantavirus that is communicable between people ran rampant on the ship, killing three passengers and putting dozens of others at risk for infection.

Other hantavirus strains are typically spread through contact with an infected rodent or its excrement.

Only one of the 17 Americans tested positive for the virus after the evacuation. That individual and another who was showing symptoms were transferred to Emory University for further evaluation, while the other 15 are quarantining at a world-class medical center in Nebraska.

Health officials have repeatedly assured that the virus poses no real threat to the public at this time.

“Such transmission is rare and generally requires close, prolonged contact with an infected individual or their bodily fluids,” officials said.

Hantavirus symptoms generally show between four and 42 days after contact, while people who are asymptomatic are generally not considered contagious.

The cruise ship first departed from Argentina on March 20 and worked its way up the Atlantic Ocean as the outbreak spread onboard.

Patient zero was identified as ornithologist Leo Schilperoord, who likely contracted the virus while birdwatching in a landfill in Argentina. He and his wife both died during the voyage.

A group of passengers left the boat between April 22 and 26 — more than a week after the Schilperoord died — prompting fears they could spread the strain across the world.