Passengers on flight from South Korea to New York quarantined over ‘highly infectious’ mystery contagion

Passengers on a flight from South Korea to New York were put into quarantine over fears of a ‘highly infectious’ contagion on board.

The plane, from Korean airline Asiana Airlines, was reportedly en route from Seoul to New York when flight radar showed it was diverted to Winnipeg, Canada, at 6:30am local time Wednesday. 

After landing, one passenger was removed and sent to St Boniface Hospital and temporarily placed in a social containment unit, a government spokesperson told Canadian media. 

The passenger has since been taken out of the unit. 

The plane with the rest of the passengers remained parked on the tarmac at Winnipeg Richardson International Airport for nearly four hours before departing for New York. 

It landed at John F Kennedy International airport at 2:35pm eastern time.

The spokesperson said the quarantine was a precaution for a ‘very contagious’ disease, though the contagion has not been revealed. 

All necessary precautions were taken and there is no threat to anyone on board the plane, according to the spokesperson. 

Officials did not reveal details about the passenger’s condition or the contagion they were investigating. 

According to the CDC, the US authorizes isolation and quarantine at ports of entry for cholera, diphtheria, active tuberculosis (TB), plague, smallpox, yellow fever, viral hemorrhagic fevers like Ebola and Marburg viruses, severe acute respiratory syndromes (SARS), influenza A and measles. 

Passengers bringing viruses aboard US-bound flights for the past several months have mainly carried measles, a respiratory virus and the most infectious disease in the world.

It spreads via airborne droplets released in coughs and sneezes, which can hang in the air for up to two hours after a patient passes. 

Symptoms usually begin seven to 21 days after exposure, so many patients don’t know they have been infected until they have already exposed dozens, if not hundreds, of others. 

In the current US measles outbreak, 21 of the 1,454 total cases reported in 2025 are from international visitors traveling to the US. 

Ebola is another concern for international travel, especially amid an outbreak in the Democratic Republic of the Congo (DRC) that has infected 68 people.  

In February of this year, for example, New York City suspected two cases of Ebola in patients who had recently traveled to Uganda, where an outbreak was occurring at the time. 

It was later confirmed that they did not have Ebola, but it was not revealed what illness they were suffering from.

Ebola is spread by contact with the blood or body fluids of an infected person, as well as contact with contaminated objects or infected animals such as bats or primates.

Symptoms include fever, headache, muscle pain and weakness, diarrhea, vomiting, abdominal pain and unexplained bleeding or bruising. It has a mortality rate as high as 90 percent without treatment.

In South Korea, where the flight this week originated from, there are higher incidences of illnesses like tuberculosis and hepatitis, which could also trigger a quarantine. 

Tuberculosis, the world’s deadliest disease, is a respiratory disease caused by Mycobacterium tuberculosis. Though rare in the US, it kills 1.25million people worldwide every year.

It causes persistent and unexplained cough, coughing up blood, unexplained weight loss, fever and severe breathing issues. 

Though deadly, tuberculosis generally only infects those who have spent a significant amount of time exposed to it. 

Viral hepatitis, meanwhile, inflames the liver and can be spread through contaminated food or water, sharing needles or contact with another person’s bodily fluids, depending on the type. 

The CDC estimates there are 3,300, 14,400 and 69,000 infections every year of hepatitis A, B and C, respectively.