The county has a population of 554,622 with 262,716 males and 291,906 females (2009 census). It covers an area of 563 km2 with a population density of 1047 people per square kilometre which is the third in Kenya with an average household size of 4.5 people.

Vihiga County has 2 referral hospitals with a total of 136 health facilities and 89 community health units. The county has a doctor to population ration of 1:11800 and a nurse to population ratio of 1:1900. The average distance to the nearest health facility is 5 km. The County has a 10.8% teenage pregnancy rate with a HIV prevalence of 5.4%. Family planning services access is at 13%. The maternal mortality rate is 531 per 100,000 which the infant mortality rate is at 121 per 1000 birth.

WADADIA implements the Action on Fistula and youth empowerment programs in Vihiga County.