How is cjd transmitted?

Various: There are at least 2 forms. Classic and new variant. Classic includes sporatic and familial) sporadic - which it is unknown but usually occurs later in life. Familial- which is passed genetically. Variant- mostly contamination (small percentage- ie contaminated medical instruments or eating contaminated foods).

Usually by eating : Contaminated meat (human or animal), through contaminated surgical instruments, pituitary derived growth hormone, very rarely through blood transfusion. Most cases are sporadic. See this site for more information. http://www.ncbi.nlm.nih.gov/pubmedhealth/pmh0001792/.