Table IV.

Threat Assessment Indicators Used in the World Health Organization Measles Programmatic Risk Assessment

Threat Assessment Indicators (Information Source(s))	Rationale	Cut-Off Criteria (Risk Points)	Comments
≥1 measles case reported among children less than five years (case-based surveillance data)	Signifies risk for further transmission	No (+0) Yes (+4)	Assign risk point using annual measles case-based surveillance data from most recent year. Include confirmed, epidemiologically linked, and clinically compatible cases and exclude discarded cases.
≥1 measles case reported among persons 5–14 years (case-based surveillance data)	Signifies risk for further transmission	No (+0) Yes (+3)	Assign risk point using annual measles case-based surveillance data from most recent year. Include confirmed, epidemiologically linked, and clinically compatible cases and exclude discarded cases.
≥1 measles case reported among persons ≥15 years (case-based surveillance data)	Signifies risk for further transmission	No (+0) Yes (+3)	Assign risk point using annual measles case-based surveillance data from most recent year. Include confirmed, epidemiologically linked, and clinically compatible cases and exclude discarded cases.
Population density (population census data)	Higher risk for transmission in densely populated areas	0–50/km2 (+0) 51–100/km2 (+1) 101–300/km2 (+2) 301–1,000/km2 (+3) >1,000/km2 (+4)	Assign risk point using population census data from most recent year and divided by district area (extracted from shape files used for mapping).
≥1 measles case reported in a bordering district within the past 12 months (case-based surveillance data)	Cross-border transmission has greatest risk for importation	No (+0) Yes (+2)	Assign risk point using annual measles case-based surveillance data from most recent year. Include confirmed, epidemiologically linked, and clinically compatible cases and exclude discarded cases. Consider all land borders; for island borders, refer to local knowledge whether frequent population movement occurs with neighboring district. Consider cross-country borders if data are available.
Presence of vulnerable groups (local knowledge from national EPI manager)	Groups that are often undervaccinated or play a role in transmission	No vulnerable groups (+0) One risk point for each vulnerable group present (up to maximum of +8)	Assign one risk point for the presence of each of the following: (1) migrant population, internally displaced population, slums, or tribal communities; (2) communities resistant to vaccination (i.e., religious, cultural, and philosophical reasons); (3) security and safety concerns; (4) areas frequented by calamities/disasters; (5) poor access to health services because of terrain/transportation issues; (6) lack of local political support; (7) high-traffic transportation hubs/major roads or bordering large urban areas (within and across countries); (8) areas with mass gatherings (i.e., trade/commerce, fairs, markets, sporting events, and high density of tourists)