VANCOUVER (CBC) - The death of a woman on a Via Rail train Friday and the flu-like symptoms experienced by a group of passengers were not caused by an infectious disease and likely weren't connected, Ontario's acting chief medical officer said.

Dr. David Williams spoke at a news conference in Toronto, hours after a woman fell ill and died on the train, which was travelling from Vancouver to Toronto. It was placed under quarantine in the small northern Ontario town of Foleyet.

"While the cause of death continues to be under investigation, it has been determined that the deceased did most likely not have an infectious disease," said Williams.

He said he didn't yet know what caused her death, but he has consulted with a doctor on the train who treated the woman, who was in her 60s. It's believed she had some symptoms of illness when she got on the train in Jasper, Alta., as part of a tour group.

The doctor on the train was alerted to the victim's deteriorating health, found her in a washroom and determined she had died minutes earlier.

Sick passengers not infectious

Williams said five other passengers who reported flu-like symptoms and were quarantined on the train do not have infectious diseases and are in stable condition. Their symptoms were mild and they weren't taken to hospital.

The sick passengers, who were also part of the tour group, had some symptoms before getting on the train and likely had mild viral illnesses. One had sought medical treatment in Alberta for a sinus infection, he said.

Another passenger who was airlifted to a hospital in Timmins, about 100 kilometres northeast of Foleyet, has no fever and no cough and doesn't have an infectious disease, said Williams. The symptoms were likely connected to an existing condition, he said.

"It happened to be confluence of three [separate events] at the same time," he said.

The train, carrying 264 passengers and 30 crew members, left Foleyet just before 7 p.m. ET and is expected to arrive in Toronto later in the night.

Two Ontario Provincial Police officers were aboard the train to keep an eye on the situation and continue their investigation into the death.

'Lots of action' in town

Earlier in the day, Carol Woodhouse, who works in the town, told CBCNews.ca that a medical helicopter, five ambulances and emergency workers were at the railway station. OPP and CN vehicles had blocked off the road leading to the station.

"There's lots of action going on," she said.

The air ambulance landed in a local baseball field, and workers dressed in white suits and face masks removed someone from the train, Woodhouse said.

"For a little town that usually has only two police officers, it's been very busy here," she said.

Town chairwoman Deborah DesRochers said people in the town were anxious to find out what caused the illnesses.

"It's the not knowing. That's what everybody is up in the air about," she said. "The quicker they can put that to rest, it'll make everyone feel happier."

DesRochers said the tiny town - which has one restaurant and no cellphone service - was "overrun" with emergency workers and news media.

Dr. Allison McGeer, the director of infection control at Toronto's Mount Sinai Hospital, said there could be many explanations for such symptoms, including influenza, food poisoning or environmental exposure.

While influenza has decreased in Western Canada, it is still active in Ontario, she said.

"There's bound to be a few of those people [on the train] who are ill," said McGeer.

With files from the Canadian Press

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