SOPs

Procedures to Reduce Human Exposure to Orf and Q Fever

Unit for Laboratory Animal Medicine
Dec 14, 2018 12:00 am

To clarify procedures necessary to safely handle sheep to decrease the risk of human exposure to contagious ecthyma (the causative agent of orf) and Coxiella burnetii (the causative agent of Q fever).

  • Responsibility

    1. Husbandry Personnel
    2. Veterinary Personnel
    3. Investigative Personnel
  • Glossary Definitions

    Orf

    Contagious ecthyma, also known as orf or contagious pustular dermatitis, can cause crusting scabs anywhere on the body. Lesions are most frequently seen on the lips, nose, eyelids, tongue, ear, udder, and mucous membranes of sheep. In humans, the disease usually causes a firm, painful nodule on the hands or fingers. This localized lesion usually persists for 1-4 weeks.

    Contagious ecthyma is transmissible to humans by direct contact with a lesion or with a contaminated fomite (e.g., bedding, equipment, manure, feed).

    Q Fever

    Most herds and flocks in the USA are infected with Coxiella burnetii, the bacterium that causes Q fever.

    • While there is a low risk of exposure from healthy cattle, sheep or goats, the highest risk of exposure to Q fever is from placental membranes, birthing fluids, and fetuses from infected sheep, goats, and cattle.
      • The bacteria can become airborne, particularly during births and cleaning of birthing areas.
    • In most individuals, the disease manifests itself as a flu-like illness that resolves in 10-14 days.
    • Women of child-bearing age or who are pregnant should be aware that this bacterium may cause miscarriage or other problems with the human fetus.
    • Employees should report occupational exposure to their physician if clinical signs of illness are noted.
    • Rarely, a person may develop a chronic infection with the Q fever organism. This can cause endocarditis - an infection on the valves of the heart that can be fatal.
    • Individuals with the following conditions should be advised of the risk of serious illness that may result from Q fever and should be discouraged from working with sheep, cattle, and goats at the time of parturition.
      • Congenital heart disease
      • Prior valvular heart disease
      • Chronically compromised or impaired immune system
      • Pregnancy

    Decontaminate

    To remove a known contaminant.

  • Procedures

    1. Personal Protective Equipment (PPE) When Entering a Room Housing Sheep

    1. The minimum required PPE for working with sheep, sheep-exposed equipment, and sheep environment is detailed on the EHS website, Protective Equipment for Working with Animals.
      1. The amount of PPE that is required is directly related to the risk of exposure to Q fever-infected substances and Orf.
    2. Don and doff appropriate PPE according to room entry sign.

    2. Sheep with Orf Lesions

    1. The following applies if a sheep in a housing room has been diagnosed with orf lesions:
      1. The husbandry supervisor designates the areas as biohazardous and posts a biohazard sign incorporating both the name "orf" and the universal biohazard warning symbol (available from ULAM or EHS).
      2. House sheep with orf lesions as far away as possible from the other animals in the housing room.
        1. Clean/spray down pens with orf-positive sheep last.
        2. Enter orf-positive rooms last in the workday.
      3. Thoroughly spray sheep cage cards with Clidox and allow to dry prior to returning to the ULAM barcode team for deactivation.
      4. Place waste and contaminated disposable materials, including acetates used in sheep housing rooms in a leak-proof bag.
        1. Seal the bag and place in a secondary container labeled as biohazardous directly outside of each sheep housing room to prevent contamination of other animals and rooms.
        2. Contact EHS HazMat for collection of biohazardous waste for disposal (3-4568).
      5. Decontaminate enrichment items and room items (e.g., buckets, feeders) with an appropriate disinfectant (see Appendix A).
        1. Place items in a leak-proof bag labeled with a biohazard sticker and seal the bag.
        2. Transport the items to cage wash for prompt processing.
    2. The following applies if a sheep in a farm setting has been diagnosed with orf lesions:
      1. Individuals working with sheep are notified by signage in the farm office
      2. Stalls or indoor housing areas that are amenable to decontamination are cleaned after animals are removed from the housing setting
        1. Environmental decontamination may not be possible or necessary in barn or pasture settings.
      3. Appropriately decontaminate materials that leave the farm or housing setting after exposure to animals with orf.
    3. Report all accidents, overt or potential exposures, or suspected cases of orf to the ULAM supervisor immediately. The ULAM supervisor immediately conveys this information to EHS (647-1143) and the area faculty veterinarian.

    3. Sheep with Increased Risk for Q Fever Transmission

    1. The following applies if a housing room contains an ewe during parturitionfetal tissuesplacenta or other birth products; a newborn lamb less than 48 hours old; or an aborted fetus:
      1. The husbandry supervisor designates the area as biohazardous and posts a biohazard sign incorporating both the name “Q-fever” and the universal biohazard warning symbol (available from ULAM or EHS).
      2. House pregnant ewes or ewes that have recently given birth separately from other animals when possible.
      3. Thoroughly spray sheep cage cards with Clidox and allow to dry prior to returning to the ULAM barcode team for deactivation.
      4. Discard any acetates used in sheep housing rooms after use.
      5. Dispose as biohazardous or decontaminate all waste (e.g. used PPE) and contaminated disposable materials (e.g. bedding, food) after the ewe, lamb, or potentially contaminated tissues have been removed from the room.
        1. Place waste and contaminated disposable materials in a leak-proof bag.
          1. Seal the bag and place in a secondary container labeled as biohazardous directly outside of each sheep housing.
          2. Contact EHS HazMat (3-4568) for collection of biohazardous waste disposal.
        2. Decontaminate all areas that held pregnant ewes with a hospital-grade disinfectant immediately after the animal has been permanently removed from the room.
          1. Decontaminate surfaces in surgical and laboratory areas with an appropriate disinfectant (see Appendix A).
        3. Decontaminate enrichment items and room items (e.g., buckets, feeders) with an appropriate disinfectant (see Appendix A).
          1. Place items in a leak-proof bag labeled with a biohazard sticker and seal the bag.
          2. Transport the items to cage wash for prompt processing (see Sheep Husbandry SOP).
      6. Transport animals at a high risk for shedding the bacteria in a solid walled, fully enclosed transport cage to minimize exposure to aerosol contamination and to prevent the spillage of potentially contaminated materials (i.e. urine, feces, bedding).
        1. Immediately clean and decontaminate the surrounding area in the event that a spill does occur.
      7. Transport all animals in transport cages (obtained from ULAM) through public corridors, on the receiving dock, and on elevators. Animals should not be allowed to remain in these areas except when being transported directly to a housing or procedure room.
        1. Spray both the interior and exterior of the transport cage with an appropriate disinfectant (see Appendix A) after the animal is unloaded at its final destination and before the cage is left in a ULAM cage wash facility.
        2. Place transport cages directly inside the cage wash facility.
        3. ULAM cage wash personnel process and wash the transport cage as soon as possible.
      8. Report all accidents, overt or potential exposures, or suspected cases of Q fever to the ULAM supervisor immediately.
        1. The ULAM supervisor immediately conveys this information to EHS (647-1143) and the area faculty veterinarian.
    2. The following applies if a sheep in a farm setting has an increased risk of Q fever transmission:
      1. Personnel working with sheep are notified by signage in the farm office.
      2. Personnel with conditions listed in the Q fever definition above should wear full PPE throughout the period of late pregnancy, parturition, and lactation while in the corrals or barns, whether in direct contact with the animals or not.
      3. Decontaminate stalls or indoor housing areas after the ewe, lamb, or potentially contaminated tissues have been removed.
      4. All waste materials from animals, including bedding contaminated with placental material, are handled as biohazardous.
        1. Dispose as hazardous waste or decontaminate all used PPE and disposable materials.
      5. Rinse off and spray dedicated farm shoes with bleach or Lysol solution while outside following use, and then placed back in the storage area inside the designated area.
        1. Wear respiratory protection while rinsing dedicated farm shoes.
        2. Never reuse disposable shoe covers.
      6. Attire worn during the period when ewes are giving birth at the farm.
        1. Dispose of water-resistant jumpsuit/coveralls as biohazardous waste.
        2. Launder attire worn underneath water-resistant jumpsuit/coveralls in washing machine with no additional precautions required.
  • Appendix A: Hospital-Grade Disinfectant Information

    1. A fresh 1:10 dilution of household chlorine bleach, a 1:100 dilution of Lysol or other approved disinfectant.
      1. Labsan, 256CPQ is not an approved disinfectant.
    2. Contact time should be 30 minutes.
    3. Bleach solutions should be used within 48 hours of mixing.
  • Appendix B: Orf Biohazard Sign

  • Appendix C: Q Fever Biohazard Sign

Species: Sheep
Questions?

If you have questions or comments about this document, contact ULAM Veterinary Staff (email ULAM-vets@umich.edu or call 734-936-1696).