Although it is a rare illness, infant botulism is incredibly serious. For this reason, parents of newborns are being reminded to refrain from feeding honey, even the smallest amount, to any child under the age of 1.
If the botulism spores are ingested, they begin to multiply in the infant’s gastrointestinal tract, producing a toxin. The toxin interferes with muscle control and nerve pathways, and can lead to paralysis and possible death.
Why risk it? Be safe, and just wait until your child is over the age 1 and has developed sufficient "good" bacteria in his or her gastrointestinal tract to fight off the potentially lethal toxin.