Nosema ceranae is an emerging microsporidian parasite of European honey bees, 
Apis mellifera, but its distribution is not well known. Six Nosema-positive 
samples (determined from light microscopy of spores) of adult worker bees from 
Canada (two each from Nova Scotia, New Brunswick, and Prince Edward Island) and 
two from USA (Minnesota) were tested to determine Nosema species using 
previously-developed PCR primers of the 16S rRNA gene. We detected for the first 
time N. ceranae in Canada and central USA. One haplotype of N. ceranae was 
identified; its virulence may differ from that of other haplotypes.