This article is part of a series of informative animal health articles. The series goes hand in hand with the #VideoVet video series – watch the video below.

Lumpy skin disease (LSD) – also known as Marokoroko in Sesotho or Isifo sama qhuqhuva in isiZulu – is a viral disease transmitted by biting insects such as stable flies, midges and mosquitoes. LSD affects farmers through its negative effects on animal productivity and profit margins, but is often ignored until it is too late for successful prevention and recovery.

All you need to know about LSD

Due to the mobility of the vector, the disease can spread over a large area via a single infected animal. Most cases of LSD occur in late summer and early autumn, usually after seasons of above-average rainfall. Within herds, the disease tends to spread where animals share drinking and feeding troughs, due to the saliva of infected animals often ending up in these troughs.

Cows secrete the virus in their milk and in this way infect their calves. People can also spread the disease by using contaminated equipment (such as re-using needles on cattle during outbreaks), or by artificially inseminating cows with infected semen.

LSD can be identified on the animals in the form of skin nodules or bumps of about 1 to 5cm. However, before these nodules become visible the animal may show other clinical signs of the disease, such as fever, increased saliva production and increased eye and nasal discharge.

Pseudo-lumpy skin disease

LSD can be confused with pseudolumpy skin disease, which is caused by Bovine herpesvirus 2. These diseases may be clinically similar, although in some parts of the world Bovine herpesvirus 2 lesions are localised to the teats and udders of cows and the disease is known as bovine herpes mammillitis.

Pseudo-lumpy skin disease is milder than true LSD, but differentiation depends essentially on isolation and identification of the virus.

Susceptible animals

All unvaccinated animals are susceptible to LSD and between 3 to 85% of a herd may be affected. Calves of vaccinated cows are protected until they are about six months old, but calves of unvaccinated cows are susceptible.

The disease has a profoundly negative impact on fertility and causes a drop in milk production. In addition, due to the severe lesions caused by LSD, the hide may be rendered unsellable. Animals can die from LSD as the nodules can also form in the lungs and throat, causing severe breathing difficulties.

As the disease is caused by a virus, it cannot be cured by antibiotics or any other medicine. Treatment is symptomatic and aimed at decreasing the fever and treating the infected nodules with antibiotics.

Vaccination

The clinical signs and economic losses of LSD can be prevented when farmers use Lumpyvax® from MSD Animal Health to vaccinate their herds.

Lumpyvax® is a live attenuated (weakened) vaccine for the prevention of LSD. The vaccine is injected under the skin at a dose of 1ml per animal and needs to be repeated every year for adequate herd protection. The best time to vaccinate is before the start of the rainy season.

Although vaccination is the most effective means of preventing LSD, control of biting insects such as flies helps to limit the spread of the disease. Susceptible animals should be vaccinated annually, preferably in spring before insect populations increase.

Because it is an attenuated live vaccine, there may be a temporary reduction in milk production in dairy cattle. Calves younger than six months, born to vaccinated cows, should not be vaccinated. The calves of unvaccinated cows should be vaccinated as soon as possible. It is safe to vaccinate pregnant cows with Lumpyvax®.

Lumpyvax®
Contains: Each 1 ml (1 dose) of vaccine
contains 10⁴ TCID50 of freeze-dried, live,
attenuated virus (SIS Neethling-type).

Indications: For the prophylactic immunisation (vaccination) of cattle against lumpy skin disease.

Dose: 1 ml per animal subcutaneously. For full details, please read product insert or visit www.msd-animal-health.co.za.

For more information, contact your MSD Animal Health representative or visit www.msd-animal-health.co.za. To watch more videos in this series, click here.