National case definition: Leprosy

Date of last revision/review: May 2008

National notification

Both confirmed and probable cases of disease should be notified.

Type of surveillance

Routine case-by-case notification to the federal level

Case classification

Confirmed case

Clinical evidence of illness with laboratory confirmation:  

• positive acid fast stain with typical morphology for Mycobacterium leprae

  or

• histopathological report from skin or nerve biopsy compatible with leprosy

Probable case

Clinical illness in a person who is epidemiologically linked to a confirmed case

Laboratory comments

Positive detection for M. leprae DNA is considered presumptive.

Clinical evidence

Tuberculoid or paucibacillary disease: one or a few well-demarcated, hypopigmented and anesthetic skin lesions, frequently with active, spreading edges and a clearing centre; peripheral nerve swelling or thickening may also occur.

Lepromatous or multibacillary disease:  erythematous papules and nodules or an infiltration of the face, hands and feet with lesions in a bilateral and symmetrical distribution that progress to thickening of the skin and loss of normal hair distribution, particularly on the face (madarosis).

Borderline (dimorphous):  skin lesions characteristic of both the tuberculoid and lepromatous forms.

Indeterminate: early lesions, usually hypopigmented macules, without developed tuberculoid or lepromatous features.

ICD code(s)

• ICD-10 Code(s) A30, Leprosy (Hansen’s disease)
• ICD-9 Code(s): 030, Leprosy (Hansen’s disease)

Type of international reporting

Elimination or eradication efforts should be reported.

Quarterly and annual reporting of aggregated data to the WHO

References

Case definitions for diseases under national surveillance. CCDR 2000;26(S3): 47.

Centers for Disease Control and Prevention. Case definitions for infectious conditions under public health surveillance. MMWR 1997;46(No. RR-10):15.

World Health Organization. Department of Communicable Disease Surveillance and Response (October 1999). WHO Recommended Surveillance Standards. 2^nd ed. WHO/CDS/CSR/ISR/99.2. Retrieved May 29, 2007 from www.who.int/csr/resources/publications/surveillance/whocdscsrisr992.pdf