LSD is a viral disease of cattle and buffalo caused by a virus closely related to sheep-pox virus and goat-pox virus. LSD is a notifiable disease according to the World Animal Health Organization (OIE) due to its potential of rapid spread and severe economic consequences. The death rate is usually around 5 % to 10%, whereas the morbidity rate ranges 5% to 45%. Although the disease is not contagious to humans, it can jeopardize the livelihoods of dairy farmers. Affected nations have suffered significant economic losses as a result of the LSD. Due to a high fever and subsequent mastitis, the disease dramatically reduces milk production by 10% to 85%. Other consequences of the disease include damaged hides, a decline in the growth rate of beef cattle, temporary or permanent infertility, abortion, treatment and vaccination costs, and the death of infected animals.
LSD was first detected in Zambia in 1929 and since then the disease spread to other sub-Saharan Africa countries. Outside Africa the disease has been gradually spreading since 1990. In Asia and the Pacific the disease was first reported in 2019 and has since spread across the region including India. Skin lesions are considered to be the primary sources of infection because the virus can survive for a long time in lesions or scabs. The virus is also excreted through the blood, milk, saliva, semen, nasal, and lachrymal discharges. The virus spread mainly occurs through mechanical transmission by insect vectors such as flies, mosquitoes, and ticks. Also, communal grazing and watering have been linked to higher rates of LSD, most likely as a result of the increased likelihood of mosquitoes and other insects transmitting the virus. Transhumance and other reasons for animal movements have also been associated with an increased risk of the outbreaks. Other risk factors associated with the spread of LSD include a warm and humid climate, a condition supporting an abundance of vector populations, such as those seen after seasonal rains. LSDV can persist in the environment for extended periods of time at room temperature, particularly in dried scabs. The virus reportedly survives in dried crusts for up to 35 days, and in air-dried hides for at least 18 days. The virus can be destroyed by disinfectants like Phenol, Chloroform, Detergents, and Bleach.
