Saint John Regional Police Staff Sgt. Mike King said the woman did not have Ebola, but had recently travelled to Africa, and that initially set off alarm bells.
"In the context of the world environment right now, we needed to ensure that we didn't have that type of environment here," said King on Sunday. "We found that it was in the best interest of the folks in the hotel and the folks that might come in the hotel, to lock down until we had a chance to reach out to public health."
King said officers were called to the Hilton around 11:15 a.m. because the woman needed medical attention. The lock down was lifted around 5 p.m.
However King stressed it was not a quarantine, saying police were only restricting movement in and out of the hotel.
A medical health officer for the region, Dr. Scott Giffin, said although the woman had travelled to Africa, she did not travel to an area affected by Ebola.
"The definition of the area in which you acquire Ebola was not on this person's itinerary," said Giffin, mentioning she had travelled to Cameroon. "There's four countries in Africa that have established an outbreak, this person did not go into those countries."
Giffin said the initial fear is that the woman had contracted Ebola.
"You see so much coverage over the Internet with international press, of course it's going to be the first thing that pops into your mind," said Giffin. "But I think if it wasn't for the Ebola outbreak, physicians could be thinking this could be cholera... this could be malaria."
He also said that it's not uncommon for someone to become sick after travelling abroad.
Giffin wouldn't comment on the woman's condition only saying she is now in hospital.
It's not the first time that Canadian health officials have acted with caution in recent weeks. A number of individuals have been placed in quarantine until it was determined they weren't suffering from the virus.
Last Sunday, public health officials in Quebec confirmed a girl who developed a fever after returning from a trip to West Africa did not have Ebola.
A week before that, a patient at a Montreal hospital tested negative for the virus, and earlier in August, testing confirmed a patient in Ontario did not have Ebola.
Fever is a common symptom of the often deadly virus which has killed more than 1,800 people in the largest Ebola outbreak on record.
Transmission of Ebola from person to person is made through direct contact with blood and body fluids of a sick person.
— By Aly Thomson in Halifax
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