Measles outbreaks spark concern over rare 'horrific' neurological disorder

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Dr. Michelle Barton has been working at the heart of Ontario's measles outbreak for months, trying to contain the damage the highly-infectious disease can wreak on children hospitalized with the virus. 

Barton heads up the pediatric infectious disease team at London Health Sciences Centre children's hospital in the province's southwest, the region with the highest rate of the illness. 

"We offer the best treatment that we can under the circumstances," Barton said. "If the child proceeds to deterioration, that is difficult to watch because you know that you probably wouldn't be here if they had had vaccines."

Barton and other doctors are worried that outbreaks in Canada will follow the same trajectory as those in the U.S., where two unvaccinated children have died of measles. Pediatricians and immunologists say they are also watching for extremely rare neurological conditions that can occur even years after children who've had measles recover from it. 

As of Friday, provincial health authorities across the country had reported 914 cases of measles, surpassing the 751 infections for all of 2011. The total is the highest since measles was eradicated in Canada more than 25 years ago. 

The bulk of the cases in the country have been reported in Ontario, with Public Health Ontario detailing 804 confirmed and probable cases of measles this year so far.

In March, the province's chief public health officer said the rise in measles cases in southwestern Ontario linked back to a travel-related case in New Brunswick last fall, which sparked what the Public Health Agency of Canada has called a multi-jurisdictional outbreak. 

P.E.I.'s Chief Public Health Office said two adults who tested positive for measles on the island had travelled together to an area in Canada where outbreaks continue. On the Prairies, provincial figures show measles cases are climbing in Alberta. 

Barton is particularly concerned about children with suppressed immune systems, such as those receiving chemotherapy. If they contract measles and "don't get to the hospital fast enough, we could end up losing patients."

In Alberta, every zone in the province now has measles. Dr. Cora Constantinescu, a pediatrician and infectious diseases specialist at Alberta Children's Hospital in Calgary, is watching the cases mount and spread, calling her worry about a death from measles "incredibly distressing." 

"We're probably looking at the beginning of a significant measles outbreak," she said.

South of the border, two unvaccinated children with no underlying health conditions have died of measles in Texas, including an eight-year-old girl last week.

On Friday the U.S. Centers for Disease Control and Prevention reported 712 cases of measles so far this year in 25 jurisdictions, including Texas and New Mexico. Gaines County, Texas, the centre of the outbreak, measles counts on Friday rose to 355, up from the 328 reported on Tuesday, the Texas Department of State Health Services said.