A serious bacterial outbreak has forced the neonatal intensive care ward at Women's College Hospital to close, posing a potential problem for Ontario hospitals.

The program, which is run by Sunnybrook Health Sciences Centre but operates out of Women's College Hospital, will no longer take high-risk pregnant mothers or transfers of premature babies born at other regional hospitals.

Those babies might have to be cared for outside Toronto, in Hamilton or London in Ontario, or even across the U.S. border in Buffalo, N.Y.

"It is difficult, it's a tough call," said Dr. Michael Dunn, who heads Sunnybrook's department of newborn and developmental pediatrics.

"The problem was we weren't really successful in containing [the infection], so to close the unit down does mean that many women and babies that need neonatal intensive care … will need to be diverted to other centres," he said.

Moving the babies worries Dr. Keith Barrington of the Canadian Pediatrics Society.

"When you transfer unstable, critically ill babies, it increases the risk of a poor outcome of the baby," he said. "In fact, transportation of the baby increases mortality rates."

The closure of the Toronto ward while it is disinfected could last weeks. It will not reopen until there are no new transmissions of the bacteria, a press release said.

The neonatal intensive care unit being operated at Women's College is Toronto's largest, and health officials say there's no extra space in the rest of Ontario, as the system is already operating at full capacity at all times.

Dunn attributed the spread of the infection to an organism called methicillin-sensitive Staphylococcus aureus, a common bacterium present on the skin of many people.

"Many people live with it quite peacefully, and in fact many of our babies became colonized with this bacteria and don't have problems."

Infected babies have been treated

Several infants had earlier developed abscesses, pneumonia and infections of the eye and blood, but no deaths have been reported. Dunn told CBC News that most of the babies only had minor infections, and those babies have been separated from the other babies in the ward. 

"All the babies who developed infections have been successfully treated, but we were not able to completely prevent the spread of the organism from one baby to another."

One of the babies who has been treated is Mandy Martin's one-month-old daughter, one of her triplets. 

Martin, who's from Lethbridge, Alta., said her daughter appears to be recovering from her infection. "She's on medication, so the medication's helping a lot," the mother said Friday. "She is getting better."

The Alberta government had flown Martin to Women's College Hospital when she was pregnant last month because there was no space in Calgary's crowded neonatal units.

One of the triplets, a son, died soon after birth, but the death is unrelated to the bacterial outbreak.

The neonatal unit has 41 beds, each in about 30 square feet of space, making for extremely crowded conditions that likely helped the infection spread easily, the hospital said.

The unit cares for one in five of all babies born in Ontario weighing less than three pounds, according to a news release.