- Caused by Burkholderia (Pseudomonas) mallei
- Exists in eastern Europe and Asia
- Notifiable in UK
- Characterised by multiple small submucosal nasal nodules which liquefy and ulcerate
- Cores of neutrophils surrounded by a rim of macrophages and granulation tissue
- In addition may have similar nodules in lungs, lymph nodes and cutaneous lymphatics
- Clinical signs: fever and head/ neck lymphadenitis, rhinitis
- Largely eradicated but sporadic cases in Middle East, India, China
- Pathogenesis:
- Transmited by ingestion of food/water contaminated by nasal discharge of infected Equidae; occasionally via inhalation or skin wounds
- Organism invades nasopharyngeal mucosa and spreads to other tissues via lymphatics
- Presence of B. mallei in host causes hypersensitivity reaction
- Clinical infections:
- Acute septicaemic form with fever, mucopurulent nasal discharge and respiratory signs; death within weeks
- Chronic disease more common:
- Nasal form: rhinitis; ulcerative nodules develop on mucosa of nasal septum and lower part of turbinates; purulent blood-stained nasal discharge; regional lymphadenitis
- Respiratory form: respiratory distress; granulomatous lesions throughout lungs
- Cutaneous form (farcy): lymphangitis; nodules along lymphatic vesselsof limbs; ulcers develop and discharge pus
- May die after several months or recover and shed organisms from respiratory tract or skin
- Carnivores may contract disease by eating infected carcasses
- Diagnosis:
- Specimens include discharges from lesions and blood for serology
- Grows on media containing 1% glycerol; most strains are non-lactose fermenters on MacConkey agar
- Complement fixation and agglutination
- Serology
- Mallein test: mallein injected intradermally below lower eyelid; local swelling and discharge indicates positive reation
- Treatment/control:
- Test and slaughter policy where disease exotic
- Disinfection of contaminated areas using formalin or an iodophor