Prion Infection Control

Prions exist predominantly in the central nervous system which is made up of your brain, spinal cord and cerebral spinal fluid (the watery solution that bathes the brain and spinal cord). Therefore, normal interaction with people who have CJD should not put you at risk of getting it too.

Social Contact

There is no evidence to suggest that you can catch CJD through normal social contact – touching, sharing utensils, kissing or sexual contact. You don’t need to wear gloves when touching a loved one with CJD or when handling their belongings. As a general rule, you should always wash your hands thoroughly with soap and water after touching anyone with any illness, but spouses and other household members of sporadic CJD patients have no higher risk of contracting the disease than the general population.

Universal Precautions

Prions are very stable molecules that do not break down easily. Normal sterilization procedures such as cooking, washing and boiling do not destroy them. Caregivers should use “universal precautions” if they are providing any type of medical care beyond social contact. These precautions include:

  • Washing your hands and exposed skin before eating, drinking or smoking.
  • Covering any cuts or abrasions you might have with waterproof dressings.
  • Wearing surgical gloves if you are dressing any wounds on the person with prion disease.
  • Avoiding cutting or sticking yourself with instruments that have also come into contact with the person with prion disease’s blood, spinal fluid or other tissues.

Tissue Infectivity for Health Care Providers

The central nervous system tissues, specifically brain, dura mater, spinal cord and eye are highly infectious. In vCJD, lymphoreticular tissues are also highly infectious. Cerebrospinal fluid (CSF) and several organs outside the CNS (lung, liver, kidney, spleen and placenta) are considered less infectious but should still be treated with caution.

Only vCJD has been shown to be transmissible by blood transfusion from human to human. Although transmission from blood in other human prion diseases (not vCJD) has not been shown, there is a theoretical risk. Therefore, any exposure with confirmed or suspected prion disease (or with a relative with CJD) must be considered exposure to prion disease.

It is not clear how cautious one needs to be in performing non-neurosurgical invasive procedures on patients with prion disease. Most medical centers treat such procedures and equipment with universal precautions. At our center, due to the high number of patients seen with prion disease, we are more cautious with invasive medical procedures.

When working or caring for patients with prion disease, casual, and even intimate, contact is not considered a risk factor. When dealing with bodily fluids and excretions, such as blood, urine or feces, we recommend universal precautions (disposable gloves and disposing of material that comes in contact with such fluids).

Route of Exposure for Health Care Providers

Human prion diseases are not known to spread by social contact, but transmission can occur during invasive medical interventions, exposure to infected human cadaveric-derived pituitary hormones, dural and cornea grafts, and contaminated neurosurgical instruments.

While there is no evidence of occupational transmission of CJD to healthcare workers, it is prudent to be cautious. The highest potential risk is from transcutaneous exposure to high infectivity tissues (CNS) through needle-sticks, puncture wounds, “sharps” injuries, or contamination of broken skin. Exposure by splashing of the mucous membranes (notably the conjunctiva) must also be avoided. Healthcare personnel who work with patients with confirmed or suspected prion disease, or with their tissues, should be appropriately informed about the nature of the hazard and relevant safety procedures.

Needle-Stick Procedure

  1. Wash the affected area with 1N sodium hydroxide (NaOH) solution for 2–3 minutes.
    1. 1N NaOH = 40 grams of NaOH per liter of water.
    2. Another option is to combine two parts 5.25% household bleach (sodium hypochlorite) with three parts water to make a 2% solution.
    3. Working solutions should be prepared daily.
  2. Rinse well afterward with soap and water to neutralize the base.
    1. Sodium hydroxide is caustic but relatively slow-acting at room temperature and can be removed from skin or clothing by thorough rinsing with water for 15–30 minutes.
    2. DO NOT use sodium hydroxide or bleach in eyes or mouth, or on any other mucous membrane. For a splash to the eye or mucous membrane exposure, rinse well with saline or tap water.
  3. Cover wound with waterproof dressing to prevent secondary contamination.
  4. Report your exposure.

 

For detailed guidelines, please read