Epizootic lymphangitis is a contagious

lymphangitis Lymphangitis is an inflammation or an infection of the lymphatic channels that occurs as a result of infection at a site distal to the channel. The most common cause of lymphangitis in humans is ''Streptococcus pyogenes'' (Group A strep), hemolyti ...

disease of horses and mules caused by the fungus '' Histoplasma farciminosum''. Cattle are also susceptible, but more resistant to the disease than

equids Equidae (sometimes known as the horse family) is the taxonomic family of horses and related animals, including the extant horses, asses, and zebras, and many other species known only from fossils. All extant species are in the genus '' Equus'', w ...

. See also glanders and equine lymphangitis.

Classification

In the

United Kingdom The United Kingdom of Great Britain and Northern Ireland, commonly known as the United Kingdom (UK) or Britain, is a country in Europe, off the north-western coast of the continental mainland. It comprises England, Scotland, Wales and North ...

it is a notifiable disease; the OIE no longer classifies it as a Listed Disease.

Symptoms

Epizootic lymphangitis usually presents with the following symptoms: * Skin eruption, usually on legs, occasionally head or neck, rarely other body parts. * The

lymph vessels The lymphatic vessels (or lymph vessels or lymphatics) are thin-walled vessels (tubes), structured like blood vessels, that carry lymph. As part of the lymphatic system, lymph vessels are complementary to the cardiovascular system. Lymph vessel ...

in the skin stand out prominently, and small hard nodules approximately 1 cm (1/2") in diameter appear on their course. * The nodules suppurate forming abscesses and discharge a thick yellow

pus Pus is an exudate, typically white-yellow, yellow, or yellow-brown, formed at the site of inflammation during bacterial or fungal infection. An accumulation of pus in an enclosed tissue space is known as an abscess, whereas a visible collection ...

Proud flesh Granulation tissue is new connective tissue and microscopic blood vessels that form on the surfaces of a wound during the healing process. Granulation tissue typically grows from the base of a wound and is able to fill wounds of almost any size ...

grows from the wounds, the lymph vessels around being

inflamed Inflammation (from la, inflammatio) is part of the complex biological response of body tissues to harmful stimuli, such as pathogens, damaged cells, or irritants, and is a protective response involving immune cells, blood vessels, and molecu ...

, and the eruption gradually extends. * The neighbouring glands are swollen and hard. The ulcers heal with difficulty, even under treatment, and they may break out again after an apparent cure had been effected.

Diagnosis

This disease is distinguished from glanders/farcy by the presence of the ''

Histoplasma ''Histoplasma'' is a genus of dimorphic fungi commonly found in bird and bat fecal material. ''Histoplasma'' contains a few species, including—''Histoplasma capsulatum''—the causative agent of histoplasmosis; and ''Histoplasma capsulatum var ...

'' organisms in the pus, and failure of the

mallein test The mallein test is a sensitive and specific clinical test for glanders, a common bacterial disease of equids (horses, donkeys, mules). This test is an allergic hypersensitivity test used as a diagnosis for glanders. It is caused by a bacterium c ...

to produce a reaction. Both Glanders and epizootic lymphangitis may be present in the same animal.

Serology Serology is the scientific study of Serum (blood), serum and other body fluids. In practice, the term usually refers to the medical diagnosis, diagnostic identification of Antibody, antibodies in the serum. Such antibodies are typically formed in r ...

can be used to assist diagnosis.

Control

Control of the disease is usually through elimination of the infection. This is achieved by

culling In biology, culling is the process of segregating organisms from a group according to desired or undesired characteristics. In animal breeding, it is the process of removing or segregating animals from a breeding stock based on a specific tr ...

infected horses and application of strict hygiene practices to prevent spread of the organism. Vaccination has been used on a limited scale in areas where enzootic lymphangitis is

endemic Endemism is the state of a species being found in a single defined geographic location, such as an island, state, nation, country or other defined zone; organisms that are indigenous to a place are not endemic to it if they are also found elsew ...

, e.g.

Iraq Iraq,; ku, عێراق, translit=Êraq officially the Republic of Iraq, '; ku, کۆماری عێراق, translit=Komarî Êraq is a country in Western Asia. It is bordered by Turkey to Iraq–Turkey border, the north, Iran to Iran–Iraq ...

, but is not authorised for widespread use.OIE ''Manual of Diagnostic Tests and Vaccines for Terrestrial Animals'' (2004), Chapter 2.5.13 {{cite web , url=http://www.oie.int/eng/normes/mmanual/A_00091.htm , title=Archived copy , accessdate=2007-06-14 , url-status=dead , archiveurl=https://web.archive.org/web/20070804182644/http://www.oie.int/eng/normes/MMANUAL/A_00091.htm , archivedate=2007-08-04

References

Animal fungal diseases Horse diseases