Distribution, burden, and impact of acute gastroenteritis in Dominica, 2009-2010.

Acute gastroenteritis (AGE) is an important public-health issue in Dominica. To determine the burden of AGE in Dominica, a retrospective, cross-sectional population survey was conducted in March-April 2009 and October 2010 (low- and-high-AGE seasons) and a laboratory survey from April 2009 to March 2010. The overall monthly prevalence of self-reported AGE was 8.6 % (95% CI 7.0-10.6); the incidence rate was 1.1 episodes/person-year and 79,157.1 episodes of AGE for the total population/year. Monthly prevalence of AGE was the highest in the 1-4 year(s) age-group (25.0%), higher in females (10.8%) and also varied by health district, with the highest monthly prevalence of AGE being reported in the Portsmouth district (13.1%). This difference in gender and across the health region was statistically significant. The estimated underreporting of syndromic AGE to the Ministry of Health was 83.3%. Furthermore, for every reported laboratory-confirmed case of AGE and foodbome disease (FBD), there was an estimated underreporting factor of 280. Overall, 47% of AGE specimens tested were positive for FBD pathogens. The predominant pathogens isolated were norovirus, followed by Giardia, Salmonella, and Shigella. The total annual estimated cost of AGE was US$ 1,371,852.92, and the total cost per capita due to AGE was US$ 19.06, indicating an economic burden of AGE-related illness on a small island of Dominica.