Lumpy skin disease is a viral disease of cattle caused by biting insects. The virus, which is closely related to sheep and goat pox viruses, causes nodular skin lesions on the body of the animal. Lumpy skin disease usually occurs in Africa; however, outbreaks have occurred in parts of the Middle East.
Clinical signs
- Nodular skin lesions on the body of the animal, muzzle, nose, head, neck , back, legs, scrotum, perineum, udder, eyelid, tail and teeth.
- Nodules can also develop internally, particularly in the respiratory and gastrointestinal tract.
- Fever;
- Listlessness and inability to eat
- Ocular and nasal discharge;
- Milk drop with loss of weight
Causes
The transmission of the LSD virus is not well known.
The key route of transmission between animals is thought to be the mechanical transmission of arthropod vectors, for example:
- biting flies
- ticks
- mosquitoes
The prevalence of insect vectors may affect the rate of transmission of the virus, which could account for a large difference in recorded morbidity (death rates) abroad.
Direct communication between infected animals is considered to play a minor or negligible role in the transmission of the virus.
Infected bulls may excrete the virus in semen, and experimental transmission has been demonstrated.
The role of fomites in transmission is uncertain, although it is thought that some may contribute to the spread of the virus.
Treatment and Control
There is no particular antiviral treatment available for infected cattle with LSD. Sick animals can be separated from the herd and protected by local wound dressing to deter fly agitation and prevent secondary infections. Systemic antibiotics may be used for skin infections, cellulitis or pneumonia, and food and water should be readily available. Local applications of insecticides to infected cattle have been made in an effort to minimize further spread, but without any obvious benefit. In addition, the LSDV RPA test is a responsive and rapid test that could be conducted on the field or at quarantine stations for the identification of the infected LSDV case.