Orf (disease)
Orf ( ecthyma contagiosum , Contagious Pustular Dermatitis , lip Grind petits ruminants , foot-and-Fußgrind ) is a skin disease and general infection of sheep , goats , chamois , reindeer and musk ox , and is through the Orf virus (Parapoxvirus ovis) , that the genus Parapoxvirus ( PPV) belongs to the family Poxviridae .
General
The disease has a cyclical course. In addition to the general infection, local and latent infections also occur.
Epidemiology
| Classification according to ICD-10 | |
|---|---|
| B08.0 | Other infections caused by orthopox viruses |
| ICD-10 online (WHO version 2019) | |
Orf is spread around the world and is highly contagious . It is transmitted through contact, through the air, and through fallen crusts and crusts. The infection can also take place via fur , wool and meat . Lambs are infected at birth or later. The morbidity is very high, the mortality is only 1%, even if in lambs sometimes 20 to 50%. Virus reservoirs are latently infected older animals.
Humans and monkeys are receptive. People who are in close contact with the ruminants become infected. However, the virus only causes small skin rashes in humans.
Pathogenesis, pathology
The virus is absorbed through mucous membranes and small skin injuries. Then there is a local virus multiplication with subsequent flushing into the blood and lymphatic system in the lymphatic organs and the liver , where the virus multiplies. This is usually followed by another washout and the viruses settle in the typical areas of the skin . This cycle can also be interrupted at any time.
clinic
The incubation period is 3 to 8 days.
The labial shape ("lip grind", "mouth grind") shows itself in the form of pea-sized vesicles and pustules on the lips , which can extend to the nose , eyelids and ears . When it dries out, dark crusts appear, which heal after 3 weeks.
The podal shape ("foot grind") manifests itself through pustules on the coronet and between the claws, which are very painful.
The genital form shows up in pustules on the udder (partly with mastitis ), inside of the thighs, pubic area and foreskin .
The malignant (malignant) form is characterized by a multiplication of pathogens in the internal organs and manifests itself in fever, fatigue, swelling of the lymph nodes , pneumonia and edema . Recovery takes weeks. Lambs in particular can starve to death because growths in the mouth, throat , esophagus and stomach lead to an unwillingness to eat.
immunology
Animals that have recovered are immune. However, the immunity is not stable depending on the severity.
diagnosis
The diagnosis can be made by electron microscopic detection of the viruses in the crusts. An ELISA is also possible. Cultivation in cultures takes longer . Indirect detection using PPV antibodies is also possible three weeks after infection .
Combat
It can be combated by vaccination with a live vaccine. Lambs must also be vaccinated, as the mother animal vaccination is not sufficient. However, no vaccine is approved in Germany.
Legal provisions
Orf can also be transmitted to humans, so it belongs to the zoonoses . However, the disease is not one of the notifiable infections listed under the German Infection Protection Act (2000) or the European Zoonoses Monitoring Directive (2003/99 / EC). The previously existing reporting obligation under the Ordinance for Reportable Animal Diseases has been repealed.
literature
- Michael Rolle, Anton Mayr: Medical microbiology, infection and disease theory . Enke, Stuttgart 2002, ISBN 3-7773-1795-0 .
Web links
Individual evidence
- ^ Ordinance on notifiable animal diseases. Status 2011 (accessed December 30, 2016)
