Iatrogenic CJD occurs when the infection is accidentally spread from someone with CJD through medical or surgical treatment.
In the past, a common cause of iatrogenic CJD was growth hormone treatment that used human pituitary growth hormones extracted from deceased individuals, some of whom were infected with CJD.
Since 1985, synthetic versions of human growth hormone have been used, eliminating the risk of iatrogenic CJD.
Iatrogenic CJD can also occur due to the use of contaminated surgical instruments. If instruments used during brain surgery on a person with CJD are not correctly cleaned before use on another person, the CJD can be transmitted.
Increased awareness of both the risks mentioned above means that iatrogenic CJD is now very rare. In 2017 there were 0 deaths from iatrogenic CJD.