Staying alert to lumpy skin disease
08 Apr 2022
Australia’s animal health system relies on veterinarians reporting any suspicion of an emergency animal disease. Lumpy skin disease has never occurred in Australia, but it is an emerging threat as it continues its spread through Asia and most recently into Indonesia and Singapore.
Lumpy skin disease is caused by a virus from the Poxviridae family. It is a serious disease that primarily affects cattle and water buffalo, although it has also been seen in other bovids and giraffes. There is no reliable evidence that the virus causes disease in humans. It is vital that veterinarians stay alert to this disease so that early detection of an outbreak can be made. The disease would have significant and far-reaching impacts should there be an incursion in Australia. There is currently no vaccine available for use in Australia.
Infection with lumpy skin disease virus typically causes painful characteristic skin nodules which cover the body of the animal. Cattle with lumpy skin disease may show firm, raised nodules up to 50 mm in diameter which develop on the skin around the head, neck, genitals and limbs. Scabs develop in the centre of the nodules. When the scabs fall off, large holes are left which may become infected. The limbs, brisket and genitals can become swollen. The virus can persist in scabs for up to four months after the animal is infected and can persist in the environment for extended periods. Other disease symptoms include fever, watery eyes, loss of appetite, and a reluctance to move. There may also be a marked reduction in milk yield, damaged hides, and abortion in pregnant animals. While some infected animals may not show signs of disease, it can kill some animals.
The disease is highly infectious and is primarily spread through biting insects such as flies and mosquitoes, and also ticks. The movement of infected animals is another cause of spread, enabling new populations of biting insects to become mechanical vectors of the disease. The disease can also be spread by fomites such as contaminated equipment (for example, used vaccine or antibiotic needles) and in some cases, directly from animal to animal. The Emergency Animal Diseases Field Guide for Veterinarians (Department of Agriculture & CSIRO 2019)1 has more specific information about lumpy skin disease, including differential diagnoses, and is free to download.
Lumpy skin disease is a nationally notifiable disease; veterinarians should be aware of what the disease looks like and report any suspected cases of the disease immediately to the Emergency Animal Disease Watch Hotline on 1800 675 888. This number will connect you with your state or territory’s department of primary industries or agriculture.
Further information about lumpy skin disease can also be found on the department’s lumpy skin disease webpage (Department of Agriculture 4 March 2022)2.
References
1. Department of Agriculture & CSIRO 2019, Emergency animal diseases: A field guide for Australian veterinarians, Canberra, available at https://www.outbreak.gov.au/for-vets-and-scientists/emergency-animal-diseases-guide
2. Department of Agriculture, Water and the Environment, 4 March 2022, ‘Lumpy skin disease’, Canberra, available at https://www.awe.gov.au/biosecurity-trade/pests-diseases-weeds/animal/lumpy-skin-disease accessed 5 April 2022.