Orf - Medtick
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Orf

What is it?

Orf is a viral skin infection you can get from infected sheep or goats (it is usually presents as a scabs around the animal’s nose and mouth, which may spread to their legs and teats).

The animals are usually vaccinated against this virus however it is possible to pass to humans if the animal has been recently vaccinated and it the vaccine is yet to work effectively or on unvaccinated animals.

  • On humans it most often affects the fingers, hands, forearms or face.
  • After exposure the incubation period of 5–6 days.
  • Orf virus lesions typically progress through six stages each lasting approximately one week.
  • It usually clears up without treatment in about 6 weeks.
Person of a weak immune system are very vulnerable to this condition and may develop large lesions and or unusual lesions. Do not wait see a medical healthcare professional.
Diagnosis Tests
  • Electron microscopy
  • Skin biopsy
  • Vesicular fluid by polymerase chain reaction (PCR)
  • Viral swab

Cause

  • Virus: Parapoxvirus genus in the Poxvirus family
  • Touching an infected animal on open skin, exposed open skin such as  sore, cut or scratch.
  • Occupation at risk:
    • Regular contact with sheep or goats:
      • Farmer
      • Shepherds
      • Bottle feed a lamb
      • Wool shearers
      • Butchers
      • Veterinarians
  • Petting or having casual contact with infected animals (and one’s human skin is exposed)
  • Handling infected equipment such as a harness
  • Being bitten by an infected animal.
  • Rare: To be passed from one person to another

Symptoms

(Normally on fingers, hands, forearms or face)

Initially:

  • The affected area of skin is small and of round appearance (like a patch) and may look a reddish-blue colour (patch of skin may look darker if you have black or brown skin)?
  • Itchy and/or tender?

Over a few weeks later:

  • The affected area of skin gets bigger and turns into a blister?
  • It is of usually 2 to 3cm, but it can grow up to 5cm?
  • It may leak fluid and/or pus before crusting over?
  • Underneath the fluid and/or pus , it is firm, red tissue underneath?

Other symptoms:

  • High temperature greater than 38°C (100°F) or over and/or chills and sweats longer than 72 hours?
  • General discomfort (muscle weakness), uneasiness or ill feeling (malaise) and/or fatigue (tiredness)?
  • Swollen lymph glands (lumps on side of neck, armpits, and groin) and/or reoccurring mouth ulcers?
  • Swollen glands on the inside of your elbow or under your arm (Any unknown lumps or swellings on any part of body)?

Complications /Information to beware of/General tips:

Do not wait, phone for ambulance if have or develop:

A secondary rash may appear 10-14 days later:

General Tips

Practice:

  • Good hand hygiene
  • Wear non-porous rubber or latex gloves and dispose if you know animal has been recent vaccinated or not yet vaccinated especially especially when you have an open cut or sore and are handling the animals mouth/muzzle area.
  • Vaccinated animals should be kept separate from unvaccinated animals until the scab has healed.
  • Sheds where lambs and goat stay should be thoroughly cleaned and disinfected.

This condition may show similar symptoms to:

Please talk to your healthcare professional (i.e. Medical Doctor/Pharmacist) for further advice

Detailed Information

Please copy and paste any key words from the title: Orf in the following respective 'Medtick References and/or Sources' to find out more about the disease (this also may include diagnosis tests and generic medical treatments).

References

https://www.cdc.gov/poxvirus/orf-virus/references.html

Orf Virus Infection in Humans—New York, Illinois, California, and Tennessee, 2004–2005
Source: MMWR. Vol. 55, No. 3; 65-68 January 27, 2006.

Compendium of Measures To Prevent Disease Associated with Animals in Public Settings, 2005

https://dermnetnz.org/topics/orf

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