Table 2. Benefit Cohort Population: Individuals and person-years.

Population Group	Population Subgroup	Benefit Cohort Population Size (2000–2007) (millions)	Average Age of MDA Treatment1	Average Years of Economic Benefit2	Person-Years (Lifetime) (millions)3
1. Protected from acquiring infection (and subsequent disease)	a) Newborns	2.2	-	43	83.8
	b) Protected from infection	0.5	20	43	15.7
	Subtotal	2.7	-	-	99.5
2. Protected from disease progression	a) Subclinical morbidity	9.4	20	43	388.6
	b) Clinical morbidity	19.3	30	33	626.6
	Subtotal	28.7	-	-	1,015.3
Total		31.4	-	-	1,114.8

¹Newborns, although not actually treated with MDA, are assumed protected from infection at the time of birth and protected from clinical disease from 20 years of age.

²Based on average life expectancy of 63 years, weighted by country-specific rates and Benefit Cohort Population in each country.

³Sum of each year lived by each individual in the Benefit Cohort Population. Equal to (Benefit Cohort Population)×(Average Years of Economic Benefit), adjusted for annual mortality.