Health officials in Halifax have suspended the licence of a pediatrician accused of improperly mixing vaccinations for about 500 children under the age of two.
The vaccinations in question were allegedly administered by Dr. William Vitale, a private physician in the Halifax area, between 1992 and 1994, and between 2003 and the present, said Dr. Robin Taylor, medical officer of health for the Capital District Health Authority.
Taylor stressed that this unusual case did not represent a health emergency.
"It's an incredibly rare situation," she told a news conference. "When vaccines that aren't meant to be mixed are mixed, it can compromise their effectiveness ... [But] it's an issue we can fix."
Taylor said health authorities are trying to contact patients and their parents to have the patients re-vaccinated to protect them from a long list of preventable diseases, including measles, mumps, tetanus, whooping cough, diphtheria, polio and rubella.
Vitale has had a licence to practise medicine in Nova Scotia since 1983. He could not be reached for comment at either his office or home.
The provincial Health and Wellness Department confirmed it started an investigation after it received a complaint from a member of the public Dec. 3.
The College of Physicians and Surgeons of Nova Scotia, which regulates the medical profession, was soon told of the complaint and suspended Vitale's medical licence Dec. 13.
Dr. Gus Grant, registrar and CEO of the regulatory body, said Vitale could face further sanctions.
The young patients involved were supposed to get two or three separate vaccinations during each visit to their doctor, but they received only one mixed dose instead, Grant said. Various vaccines are typically administered at two months, four months, six months, 12 months and 18 months of age.
Prior to 1992, and between 1995 and 2002, Nova Scotians couldn't get more than one vaccination during a single visit to the doctor.
Grant said that based on an interview he conducted with Vitale on Dec. 12, it appears the doctor wanted to reduce the pain caused by multiple injections.
"Part of it was rooted, perhaps, in the sense that this would be one less shot for each baby," Grant said.
But it's not the first time Vitale has been accused of improperly mixing vaccinations.
Taylor said the province's Public Health Department learned of a similar incident in 2006, when health officials accused Vitale of mixing vaccines for seven patients.
"His inappropriate practice was corrected," Taylor said. "It was not seen to be a bigger issue at that point in time. The seven patients involved were re-immunized, and Dr. Vitale was explicitly told to stop this practice."
The College of Physicians and Surgeons was not told of what happened in 2006, in keeping with the procedures in place at the time, Taylor said, adding she was not aware of any follow-up by provincial health officials.
Taylor said the mixing of vaccines was so rare that its impact on human health is unknown.
"We don't have the medical literature to explain what happens when you do this," she said.
Grant said there was no evidence that anyone has been made ill.
"To my knowledge ... there's been no change in the incidence of serious responses to vaccinations," he said. "If [the question] is whether anyone has been harmed by this, we know of none."
He said health authorities in Ireland dealt with a similar problem in 2011-12 involving about 300 patients who were given mixed vaccinations.
"They didn't find any case of vaccine-preventable diseases," Grant said.
In the latest case in Nova Scotia, those affected will be notified by mail, Taylor said. However, health officials may not be able to reach those who have changed their address, she said.
Affected patients are being encouraged to immediately contact their family physician or to call 811, the province's helpline for health matters. Those in the Halifax area who don't have a family doctor are being encouraged to get their shots at a clinic beginning Jan. 8 at the QEII Health Sciences Centre.