Lumpy Skin Disease

Lumpy skin disease (LSD) is a highly infectious viral

disease of cattle that is characterized by fever and

the appearance of various–sized lumps, or nodules,

in the skin covering all parts of the body.

The death rate from LSD generally is low, but the

economic impact often is high because of export

restrictions. The infected cattle become lame, lose

weight, and drop in condition rapidly. In addition, milk

production in cows with LSD decreases or stops

completely, and there is significant damage to hides.

This foreign animal disease does not affect

humans or other species besides cattle. It has never

occurred in the United States. The disease has

spread over most of Africa and has affected Kuwait,

Egypt, and Israel.

How it Spreads

LSD spreads between herds in an irregular 

pattern. It may even seem to bypass cattle housed

close to the original outbreak and appear in cattle in

a herd several miles away. LSD is spread by biting

insects and direct contact with an infected animal. It

is possible that LSD is passed to calves through the

milk of an infected dam.

There are great variations in infection rates

among herds. In an endemic area, 5 to 50 percent of

the cattle in naturally exposed herds normally show

signs of the disease. However, in experiments, 40 to

50 percent of the cattle inoculated with LSD virus

develop the disease. In a susceptible population,

infection rates occasionally rise above 50 percent.

Clinical Signs

LSD may affect cattle of any age, but young

calves may be the most severely affected.

Characteristic lumps, or nodules, appear in the skin

of the cattle suddenly 2 to 4 weeks after susceptible

cattle are exposed. These lumps, which give the 

disease its name, vary in size from somewhat smaller

than a dime to about the size of a silver dollar. They

are painful, firm, well–defined, raised areas that 

usually have a flattened surface.

Lumps may spread over the entire skin surface of

the body and may extend into the respiratory and

genital tracts. Frequently, the center of the lump dies,

becomes dry, forms a deep scab, and falls out, 

leaving a raw area that may become infected. The

lumps may also disappear without treatment within a

few days or become hard and persist for more than a

year.

Most deaths in cattle with LSD are a result of

secondary infections. When lumps become infected,

large areas of dead tissue and skin slough away. The

bacterial infection may become generalized with the

animal losing condition quickly. In severe cases, 

cattle usually die about 10 days after lumps first

appear. Some cattle with large, raw, open sores will

remain alive beyond this period; usually it is advisable

to euthanize them for humane purposes.

Swellings usually develop as a result of fluid

accumulation in the tissues. These swellings, or 

edemas, usually are found in the front legs, brisket,

lower neck, udder, or lymph nodes.

Other LSD signs include a rough hair coat and a

stiff gait. Occasionally, affected cattle have 

discharges from the eyes, nose, and mouth.

In native African cattle, death losses generally

are low (1 to 3 percent). In European breeds, 

10 percent or more of the infected cattle may die.

Tentative diagnosis of LSD is based on a careful

examination of suspect cattle by a veterinarian. The

diagnosis must be confirmed by laboratory tests.

Prevention and Control

In most affected countries, control of LSD has

been only partially successful. Wide–scale eradication has not been attempted in areas where the 

disease is entrenched, but control programs have

been able to limit outbreaks and restrict the spread of

disease. Usually, cattle affected with LSD recover.

Full recovery may take 3 to 6 months, depending on

the severity of the illness.

The following disease–fighting measures have

been used against LSD:

• quarantines

• slaughter of infected and exposed cattle with 

proper disposal of animals and contaminated 

material

• extensive cleaning and disinfection of the infected

premises, equipment, and facilities

• restrictions on the movement of all livestock in 

the affected area

• restrictions on the movement of contaminated 

hides from the affected area

• regular vaccination of cattle with attenuated LSD 

virus, in the affected areas has been successful

• intensive insect control, including widespread use

of insecticides.

Factsheet

Veterinary Services October 2003

APHIS
The Animal and Plant Health Inspection

Service’s Role

Many precautions are taken by the U.S.

Department of Agriculture’s (USDA) Animal and Plant

Health Inspection Service (APHIS) to prevent the

introduction of foreign animal diseases, such as LSD,

into this country.

APHIS prohibits the importation of cattle from

countries with either foot–and–mouth disease or

rinderpest. Because these diseases occur throughout

the regions where LSD exists, it has not been necessary to impose import restrictions related specifically

to LSD. As a further precaution, the United States

requires that every imported animal have an official

veterinary certificate of health from its native country.

Imported cattle are inspected at U.S. ports of entry,

where they are further treated and quarantined, as

necessary.

In cooperation with the U.S. Department of

Homeland Security, APHIS maintains a constant alert

status to protect American livestock from foreign 

animal diseases such as LSD.

What the U.S. Livestock Owner Can Do

Livestock owners are the first line of defense

against the introduction of LSD into the United States.

To help prevent any such introduction, livestock owners should inspect their flocks and herds frequently for

lumps characteristic of LSD in their cattle and report

any suspicious, conditions to their local veterinarian or

to their State or Federal animal health officials immediately.

Additional Information

For more information contact

USDA–APHIS–Veterinary Services 

Emergency Programs

4700 River Road, Unit 41

Riverdale, MD 20737

Phone: (301) 734–8073

Fax: (301) 734–7817 

or visit the APHIS Web site at 

www.aphis.usda.gov.

The U.S. Department of Agriculture (USDA) prohibits discrimination

in all its programs and activities on the basis of race, color, national

origin, sex, religion, age, disability, political beliefs, sexual orientation, or marital or family status. (Not all prohibited bases apply to

all programs.) Persons with disabilities who require alternative

means for communication of program information (Braille, large

print, audiotape, etc.) should contact USDA’s TARGET Center at

(202) 720–2600 (voice and TDD).

To file a complaint of discrimination, write USDA, Director, Office of

Civil Rights, Room 326–W, Whitten Building, 14th and

Independence Avenue, SW, Washington, DC 20250–9410 or call

(202) 720–5964 (voice and TDD). USDA is an equal opportunity

provider and employer.

United States Department of Agriculture • Animal and Plant Health Inspection Service • Safeguarding American Agriculture