LUMPY SKIN : An Emerging transboundary disease
Dr. Srishti Soni1, Dr. Babul Rudra Paul1, Dr. Jitender Gandhar1, Dr. Varun Sarkar2 and Dr. Ujjwal Kumar De3
1Ph.D. Scholar, Indian Veterinary Research Institute, Izzatnagar, Bareilly (U.P)
2M.V.Sc. Scholar, Indian Veterinary Research Institute, Izzatnagar, Bareilly (U.P.)
3 Senior Scientist, Indian Veterinary Research Institute, Izzatnagar, Bareilly (U.P.)
Lumpy skin disease, first reported in Zambia in 1929 and the epidemic spread to neighbouring African countries and eventually reached the Middle East. (Tuppurainen and Oura, 2012) is an important infectious transboundary viral disease of cattle caused by Lumpy skin disease virus genus capripox of Family Poxviridae and this virus is antigenically closely related to goatpox and sheeppox viruses (OIE, 2010). This is economically devastating due to significant milk yield loss, infertility, abortion and death. Animal become infected via bite of blood-feeding arthropods including Hard ticks, biting flies and mosquitoes (Chihota et al., 2001), direct contact between infected and susceptible animal, drinking water and ingestion. Drinking is the most common mode of transmission. In Africa, African buffalo are regarded as maintenance hosts while Other wildlife species, however, may be involved (Radostits et al., 2007).
Animals that are clinically diseased are the most frequent cause of infection in healthy animals. However, the LSD virus can be found in blood, skin lesions, saliva, nasal discharge, lachrymal secretions, milk, sperm, and feeding and drinking troughs, all of which potentially be transmission sites (Abera et al., 2015).
The disease’s morbidity is highest during wet, warm weather and drops throughout the dry season. Depending on the immunological condition of the hosts and the amount of mechanical arthropod vectors, the morbidity rate varies greatly. Morbidity of disease varies according to immune status of the animal and ranges from 3% to 85%.(OIE, 2008). Moreover, in natural epidemics, it can reach 100%, while the fatality rate seldom exceed 5% but can occasionally reach 40%.
The disease has incubation period of 2-4week. The virus causes febrile reaction due to viraemia and localizes in skin and regional lymph node causes development of inflammatory nodules in the skin and lymphadenopathy. There is lacrimation, nasal discharge, salivation and lameness. The skin lesion first appears on the skin In severe cases, due to vasculitis there is thrombosis. The skin lesion is seen first in perineum as round firm 1-4cm in diameter as grey-pink flattened circular painless nodules restricted to intradermal region. These nodules in later course of disease changes to caseous necrotic cores.
Epidemiology, clinical indicators, necropsy evidence, and laboratory interpretations can all be used to diagnose lumpy skin condition. Multiple skin nodules with limited areas of raised hair, nodules around nostrils, turbinate, mouth, vulva, and prepuce that can survive as hard lumps or become moist, necrotic, and slough are pathognomic nodular lesions. There is also leg oedema and superficial lymph node swelling.
Despite a preliminary clinical diagnosis of LSD, traditional PCR is used to confirm the diagnosis ( Zheng et al., 2007) or real-time PCR techniques (Balinsky et al., 2008)
LSD is diagnosed during postmortem by examining for nodules on the skin, in the mouth, nostrils, vulva, and prepuce, as well as swelling of the superficial lymph nodes and systemic signs. Laboratory diagnosis of LSD can be made by transmission electro microscopic isolation and identification of the agent, Serological tests, routine histopathological examination and immune histological staining (Amenu et al., 2018).
There is no specific antiviral treatment available for LSD infected cattle. Sick animals may be removed from the herd and given supportive treatment consisting of local wound dressing to discourage fly from worry and prevent secondary infections.
Lumpy skin disease (LSD) is a monetarily devastating viral illness that affects cattle and is marked by distinctive nodular lesions mostly on the skin, lowering hide quality. In endemic areas, the mainstay of LSD control and prevention is annual immunisation of cattle older than six months. Consequently calves born to immunized cows will have a six-month period of passive immunity. Also restriction of animal movements, isolation and slaughter of affected animals, proper disposal of carcasses, cleaning and disinfection of the premises and insect control are include control measures for LSD.
Reference
Abera, Z., Degefu, H., Gari, G. and Ayana, Z., 2015. Review on epidemiology and economic importance of lumpy skin disease. International Journal of Basic and Applied Virology, 4(1), pp.8-21.
Amenu, A., Bekuma, F., Abafaji, G. and Abera, D., 2018. Review on epidemiological aspects and economic impact of lumpy skin disease. J Dairy Vet Sci, 7(4), p.555716.
Balinsky, C. A., Delhon, G., Smoliga, G., Prarat, M., French, R. A., Geary, S. J., Rock, D. L., & Rodriguez, L. L. (2008). Rapid preclinical detection of Sheeppox virus by a real-time PCRassay. Journal of Clinical Microbiology, 46, 438–442. https://doi.org/10.1128/JCM.01953-07
Chihota, C.M., Rennie, L.F., Kitching, R.P. and Mellor, P.S., 2001. Mechanical transmission of lumpy skin disease virus by Aedes aegypti (Diptera: Culicidae). Epidemiology & Infection, 126(2), pp.317-321.
OIE (2008) Lumpy Skin Disease (Neethling, Knopvelsiekte): A technical Report. The Centre for Food Security and Public Health, Iowa State University.
OIE (2010) OIE Manual of Diagnostic Tests and Vaccines for Terrestrial Animals. Lumpy skin disease. pp. 768-778.
Radostits OM, Gay CC, Hinchcliff KW, Constable PD (2007) Veterinary Medicine: A textbook of diseases of cattle, horses, sheep, pigs and goat. (10th edn), WB Saunders Co, Philadelphia, USA.
Tuppurainen, E.S.M. and Oura, C.A.L., 2012. lumpy skin disease: an emerging threat to Europe, the Middle East and Asia. Transboundary and emerging diseases, 59(1), pp.40-48.
Zheng, M., Liu, Q., Jin, N. Y., Guo, J. G., Huang, X., Li, H. M., Zhu, W., & Xiong, Y. (2007). A duplex PCR assay for simultaneous detection and differentiation of Capripoxvirus and Orf virus. Molecular and Cellular Probes, 21, 276–281. https://doi.org/10.1016/j.mcp.2007.01.005
