A Canadian individual who recently returned home from Beijing has died from H5N1 avian flu — marking not only the first human fatality from the virus in North America, but the first reported case at all.

Health officials confirmed the case on Wednesday, while reinforcing that the death was most likely an isolated incident. While H5N1 is what's known as a zoonotic avian flu virus — meaning it can cause illness in humans — the vast majority of human H5N1 cases have occurred when individuals interact closely with poultry. Transmission of H5N1 between humans is also exceedingly rare, meaning that even those who travelled or lived alongside this particular patient don't face much risk of contracting the illness.

"I want to reassure the public this is an isolated case," Rona Ambrose, Canada's Health Minister, told reporters. "The risk of H5N1 to Canadians is very low. There is no evidence of sustained human-to-human transmission."

Since 2003, according to the World Health Organization, some 648 cases of H5N1 have been confirmed in human patients. Of those, 384 patients have succumbed to the illness — around a 60 percent fatality rate. Given the virus' severity, health experts have expressed concerns that any mutations making it more readily transmissible would be a major public health concern. In that vein, ongoing research efforts — some of them controversial — continue to study the virus in the hopes of devising more effective prevention and treatment strategies.