RATIONALE FOR SURVEILLANCE

Dracunculiasis is the subject of a global eradication programme (9GPW, target 6.1). Surveillance is therefore essential to identify and contain all individual cases in endemic countries as well as in countries where environmental conditions are appropriate for local transmission of the disease.

RECOMMENDED CASE DEFINITION

Clinical case definition

A case of dracunculiasis is defined as an individual exhibiting or having a history of a skin lesion with the emergence of a Guinea worm. A recent history (within one year) of a skin lesion with emergence of a Guinea worm (Dracunculus medinensis) is the only time-frame which must be used in surveillance programmes.

RECOMMENDED TYPES OF SURVEILLANCE

Peripheral level: In all endemic and formerly endemic countries, village-based surveillance aims to detect cases while the worm is pre-emergent or at latest 24 hours after the beginning of worm emergence, even in the most remote local villages. Community-oriented case-containment interventions are combined with surveillance to interrupt further transmission of the disease. The lack of previously trained health workers in very remote localities and the needs of health workers in newly identified endemic villages continue to make training an important activity.

Intermediate/central level: Reports (aggregated data) are gathered from all villages to intermediate level and channelled towards the central level on a monthly basis. This is generally combined with supervision activities at all levels of the national dracunculiasis eradication programmes. When the annual incidence is close to zero, cases should be reported on a weekly or even daily basis.

International level: Reports from endemic countries are aggregated and reported to the international level on a monthly basis, and used as a policy basis and for managerial decisions by central programmes, as well as by external supporting agencies.

RECOMMENDED MINIMUM DATA ELEMENTS

Case-based data:

Unique identifier, sex, age, geographical coordinates of the village involved, date of diagnosis, case isolation measures taken.

Aggregated data:

For every village, number of cases by month and year.

RECOMMENDED DATA ANALYSIS, PRESENTATION, REPORTS

Monthly and yearly incidence by village, geographic origin of imported cases.

Analysis of monthly and yearly changes in the distribution of infected villages.

Mapping of data including the matching of endemic villages with water distribution data, using geographical information system (GIS).

PRINCIPAL USES OF DATA FOR DECISION-MAKING

 

• Plan interventions and supervision at all levels of the programme
• Monitor progress and the need for resources of various types
• Identify variations in case-containment efficacy
• Identify technical and operational difficulties at all levels
• Identify areas needing special interventions, training and supervision
• Evaluate the impact of programme activities

SPECIAL ASPECTS

None.

CONTACT INFORMATION

Regional Offices

See Regional Communicable Disease contacts on section "Communicable disease contacts in Regional Offices".

Headquarters: 20 Avenue Appia, CH-1211 Geneva 27, Switzerland

Eradication and Elimination of Diseases (CEE/CDS)

 

Email zagarian@who.ch / Surveillancekit@who.ch
Tel: (4122) 791 2574/4373
Fax: (4122) 791 4777/0746 attn CEE