Local public health authorities are trying to figure out how the little girl, who is under two years of age, contracted the virus.
Neither she nor members of her family had recently been in Toronto, where measles cases have been occurring, said Jon Bouma, acting director of clinical services for the Algoma Public Health Unit.
The child lives in Elliot Lake, a city of about 11,000 people which is halfway between Sudbury and Sault Ste. Marie on the north shore of Lake Huron.
She is the 19th measles case recorded in Ontario since late January. The other cases have been diagnosed in the greater Toronto area and in the Niagara region. The cases from Niagara are believed to be linked to the Toronto outbreak.
Meanwhile, a separate outbreak in Quebec continues to grow, with 26 cases reported as of Tuesday, Pascale Lamy, a spokesperson for the Lanaudiere health region, said via email.
The Quebec cases are linked to the large Disneyland outbreak in California, which to date has sparked 133 infections in seven U.S. states. Lamy said 25 of the Quebec cases are known to be linked to the California outbreak. The source of the infection for the 26th person is currently not known.
Measles symptoms include a high fever, a bright red rash, a cough, a runny nose and red, watery eyes. Most people who contract it recover fully, though the virus can make some — especially young children — very sick.
The U.S. Centers for Disease Control says one in 20 children with measles will develop pneumonia. Permanent brain damage and deafness are also complications of measles. And for every 1,000 children who contract measles, between one and three children will die.
On Tuesday, authorities in Germany announced that an 18-month-old boy in Berlin died from measles. Berlin has recorded 570 cases in an outbreak that started last October.
The family of the little girl from Elliot Lake did travel to Sudbury during the time before the child became sick, Bouma said. But no cases of measles have been reported there, so that does not shed any light on the mystery of how she contracted the virus.
Likewise, there does not appear to be a link between a large religious rally held in Toronto in early February and the Elliot Lake case. Someone who later came down with measles attended the Acquire the Fire event, which drew about 1,300 people from around the province. But Bouma said it is not believed anyone from the Algoma health region was in attendance.
"We have not found the proverbial smoking gun yet," he admitted.
The health unit hopes to receive information from the National Microbiology Laboratory in Winnipeg on Wednesday that should at least indicate whether this case is linked to the southern Ontario outbreak.
The Elliot Lake case may not be the last for the region.
The little girl attended a daycare that also looked after 103 other children. The girl also went to the emergency department of her local hospital on four occasions before her illness was recognized as measles.
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