Glanders (Farcy) Disease

Glanders (Farcy) Disease is a highly contagious and chronic disease of solipedes and is characterized by the development of nodules, ulcers in upper respiratory tract, lungs, and cutaneous tissues.

The disease is transmissible to human beings.

Etiology

Glanders is caused by Burkholderia mallei (Pseudomonas mallei). Burkholderia pseudomallei causes Melioidiosis.

Pseudomonas mallei is a medium sized 0.5-1.0 x 1.5-5.0 µm in length. It is a gram negative, rod shaped, strict aerobic organism. B. mallei is a non motile organism.

Some species produce soluble pigments. Most will grow on MacConkey Agar. It is an opportunistic pathogen.

Epidemiology

Prevalence of infection

The disease is prevalent in horse rearing countries. Glanders has been reported from Eastern Europe, India and Africa. North America and Thailand are almost free from glanders. Through strict isolation, adequate sanitation and mallein test, the disease problem has been reduced.

Sources of infection

Sources of infection are soil, infected secretions, carrier animals.

Transmission

• Ingestion through oral
• Inoculation through skin invasion
• Inhalation via air ways
• Direct contact
• In man via broken skin contact with exudates

Host affected

It causes glanders or farcy (the skin form) in equines. Occasional infection in dogs, goats, sheep and camels occurs.

Cattle, pigs, rats infected through contaminated food and water, less commonly by aerosols and through wounds.

Pathogensis

The organism gains access through intestinal mucosa leads to septicemia in acute and bacterimia in chronic phase.

It invades the regional lymph nodes through pharyngeal mucosa and undergo proliferation.

From the skin wound the organism reaches the blood stream and localized in various organs and forms nodules and ulcers in the skin.

Involvement of lungs via inhalation leads to severe broncho-pneumonia.

P. aeurugenosa produces a number of proteins exotoxins, entero toxins causes diarrhoea during initial infections. Endotoxin and numerous extracellular products such as proteases and haemolysin play an important role in pathogenesis.

This organism possess pile which facilitates adherence to epithelial cells. Some strains have a capsule that is antigphagocytic in characters.

Bacteriosins (pyocins) and pigments exhibits antimicrobial actions. Blue green pigment is pyocyanin can stain wool greenish blue.

It is an opportunistic organism involves in primary disease very rarely.

Clinical Signs

• Incubation period varies few days to several months.
• Chronic nasal discharge in or both nostrils grey in colour and catarrhal in nature.
• Formation of small, grey or yellowish nodules about the millet seed size on the mucosa of the upper respiratory tract.
• Submaxillary lymph nodes are edematous in nature.
• Nodules and ulcers formed along the lymphatic channels of the skin.
• Skin of the lower limbs and abdomen are mostly affected.
• The skin affection is ascribed as Farcy. 
• High temperature with ocular and nasal discharge, dyspnoea due to swelling of nasal mucosa and edema of glottis.
• Ulcers formed due to the infection is little resistant to healing Chronic form Persists for few months or even a year.
• Intermittent fever, cough, respiratory distress, lymph node of the mandible turn firm and nodular.
• Edema of the hind limbs down upto hock region accompanied with discharges from lymph nodes.
• Ulcers gradually heals up leaving irregular star shaped scars.

Zoonosis

• High temperature, swelling and pain usually on the hands, lips, eyes, accompanies with swelling of neighbouring lymph nodes.
• Ulcers develop on nose, mouth in some cases.
• Abscess development and pustules in the skin are the important features of the disease.

Necropsy Findings

• Nodules and ulcers in nasal septum turbinate bones.
• Small nodules observed throughout the lips varying in size from millet to pea size.
• Catarrhal bronchopneumonia and purulent lymph adenitis.

Diagnosis

• Based on clinical signs and necropsy findings.
• Identification of organism: Gram negative, rod shaped organism can be seen in Gram staining of pus smears.
• Isolation of organism.
• Fluorescent Antibody Technique: May be useful for detection antibody, Both cell mediated and antibody mediated complement fixation test, agglutination test, haemagglutination test and counter immune electrophoresis. False positive reaction of glanders occurs where melioidosis is endemic as serological tests may detect antibodies that cross react with those of P. pseudomallei.
• Mallein test: Demonstrate hypersensitivity reaction with P.mallei. Mallein is a glycoprotein extracted from bacteria and injected s/c route in infected animals results in swelling at the injection site.
• Conjunctival Mallein Test: (ophthalmic) In 6-12 hours an inflammatory and purulent reaction in eye develops.
• Intrapalpebral Test: In lower eyelid mallein is injected and produce localized edematous swelling, purulent conjunctivitis.
• Strauss reaction: Male guinea pigs are injected intra peritoneally with mallein antigen 0.5ml shows peritonitis, purulent inflammation of testicular tunica vaginalis in 2-3 days followed by orchitis.

Sample Collection

• Pus material
• Lymph node discharge
• Swabs

Differential Diagnosis

• Epizootic lymphangitis
• Ulcerative lymphangitis
• Sporotrichosis
• Melioidosis
• Others cases of pneumonia

Treatment

Treatment with Sodium sulphadiazine has been found to be effective in experimental cases. It is highly effective.

Combination of formalized preparation of mallein and sulfadiazine or mallein and sufadimidine can be given.

Prevention

Glanders is a notifiable disease under the glander or farcy act. As per the act animals declared positive must be destroyed and safely disposed.

Glanders is a notifiable disease in many countries around the worldwide. Confirmed infection may be indicated by restrictions on international trading and local movement of animals.

The appropriate Ministry Agency must be informed of all suspected or confirmed cases as it is a biological weapon in the warfare.

Control

• Carcass buried and incinerated.
• All incontact, suspected, imported animals must be isolated and tested.
• Positive reactors must be slaughtered.
• Manure, bedding materials and residuals must be burnt and buried.
• Complete quarantine of affected animals.
• Remaining animals must be subjected to mallein test at an intervals of 3 weeks.
• Disinfection of premises.
• Readily destroyed by direct sunlight and by common disinfectants.
• The organism survive for 20 days and in contaminated stable for 6 weeks.