Lumpy skin disease (LSD) is a viral illness that affects cattle, causing fever, swollen lymph nodes, and firm, raised nodules across the skin. It does not infect humans. The disease is caused by the lumpy skin disease virus, a member of the same virus family that causes sheep pox and goat pox. While rarely fatal, it can devastate cattle herds economically through lost milk production, permanent hide damage, and long recovery times.
What Causes It
The virus behind lumpy skin disease belongs to a group called capripoxviruses. These are large, sturdy DNA viruses that primarily target the skin and internal organs of hoofed animals. Cattle and water buffalo are the main species affected. The virus spreads primarily through biting insects, particularly mosquitoes, flies, and ticks that feed on an infected animal and then bite a healthy one. This insect-driven transmission means outbreaks tend to spike during warm, wet seasons when vector populations are highest.
Direct contact between animals can also spread the virus, especially through shared water troughs, feeding equipment, or contaminated bedding. Infected animals shed the virus in saliva, nasal discharge, and skin lesions. The virus is notably resilient in the environment, surviving in dried scabs and shed skin for extended periods.
Incubation and Timeline
After exposure, cattle typically develop symptoms within 2 to 5 weeks, though the World Organisation for Animal Health (WOAH) formally lists the incubation period as 28 days. In experimental settings, some animals have developed fevers as early as 6 to 9 days after infection, with skin lesions appearing around the inoculation site within 4 to 20 days. Recovery is slow, and scarring on the hide is common even after the animal improves clinically.
Signs and Symptoms in Cattle
The hallmark of lumpy skin disease is the appearance of firm, round nodules scattered across the animal’s body. These nodules can range from small bumps to large, raised masses several centimeters wide, and they tend to appear on the head, neck, limbs, udder, and genital area. The nodules often extend deep into the tissue, sometimes involving the underlying muscle.
Before or alongside the nodules, infected cattle usually develop a high fever, lose their appetite, and show visibly swollen lymph nodes. Milk production drops sharply, sometimes falling by as much as 50% in affected herds. In severe cases, cows stop producing milk altogether. Eyes and nose may discharge fluid, and the animal often appears depressed and reluctant to move. Some cattle develop swelling in the legs and along the chest or belly.
Not every animal in a herd shows the full range of symptoms. Some develop only a few nodules and recover quickly, while others become severely ill with widespread skin involvement and secondary bacterial infections in the damaged skin.
Economic Impact on Farmers
Even though mortality rates are generally low, lumpy skin disease hits farmers hard financially. The steep drop in milk production is one of the biggest losses, particularly for dairy operations. Hide damage is another significant cost. The deep scarring left by skin nodules permanently reduces the commercial value of cattle hides, which also hurts the downstream leather and tannery industries.
Beyond these direct losses, affected herds face trade restrictions. Countries with active outbreaks often lose access to international livestock and beef markets, compounding the economic damage well beyond individual farms. The cost of vaccination campaigns, movement controls, and quarantine measures adds up quickly at both the farm and national level.
How It’s Diagnosed
Veterinarians can often suspect lumpy skin disease based on the characteristic combination of widespread skin nodules and swollen lymph nodes. But laboratory testing is needed to confirm it, since other conditions can look similar.
The fastest and most reliable confirmation comes from PCR testing, which detects the virus’s genetic material in skin biopsies, blood samples, or tissue from the nodules. PCR can identify the virus even after the animal has started producing antibodies, and viral DNA remains detectable in samples for up to 3 months after infection. For direct virus isolation, samples are best collected within the first week of symptoms, though the virus can be recovered from skin nodules for up to 35 days. A blood-based neutralization test is the only validated method for detecting antibodies, which can help confirm past infection in a herd.
Vaccination and Prevention
Vaccination is the primary tool for preventing lumpy skin disease. The most widely used vaccine is based on a weakened (attenuated) form of the virus called the Neethling strain. In a large randomized field trial of nearly 4,700 cows, the Neethling vaccine proved significantly more effective than an alternative sheep pox-based vaccine. Cattle given the sheep pox vaccine were roughly 2.6 times more likely to develop the disease and over 11 times more likely to develop severe illness compared to those vaccinated with the Neethling strain.
The Neethling vaccine does carry a small trade-off: about 0.38% of vaccinated cows in the trial developed mild vaccine-associated disease. This is a very low rate, and the protection it offers far outweighs that risk, especially in regions where outbreaks are active or expected.
Beyond vaccination, controlling insect populations through insecticides and repellents helps reduce transmission. Quarantining new or sick animals, disinfecting equipment, and restricting cattle movement during outbreaks are all standard parts of a prevention strategy.
No Risk to Humans
Lumpy skin disease is not zoonotic. There is no evidence that the virus can infect people, whether through direct contact with sick animals, handling raw hides, or consuming milk or meat from infected cattle. WOAH states plainly that the disease poses no threat to human health. The concern is entirely economic and animal welfare-related.
Where the Disease Occurs
Lumpy skin disease was historically confined to sub-Saharan Africa, where it was first identified in the 1920s. Over the past two decades, it has spread dramatically. The virus moved through the Middle East and into southeastern Europe during the 2010s, prompting emergency vaccination campaigns across the Balkans and Turkey. More recently, outbreaks have swept through South and Southeast Asia, affecting countries including India, Bangladesh, China, Vietnam, and Thailand. The rapid geographic expansion is driven by international cattle trade, movement of animals across borders, and the wide range of insect species that can carry the virus.