Dengue surveillance system: are we capturing all cases?


Background: Dengue is the most important arthropod borne viral diseases causing morbidity and mortality. In Malaysia, dengue trend increases each year from 44.3/100,000 populations in 1999 to 181/100,000 populations in 2007. Notification of dengue is mandatory by Law and surveillance activities are an important component in the National Dengue Strategic Plan. This study was to evaluate the dengue surveillance system in an urbanized district in Malaysia. Methods: Dengue surveillance system was reviewed using usefulness, timeliness, completeness and coverage attributes. The CDC Surveillance Guidelines for Evaluating Public Health Surveillance Systems was used as guide. Officers from 3 levels; State, District and Clinics were interviewed using structured questionnaire. Results: During a 2 week study period, 500 cases were notified to the district health office (DHO); 58% notified within 24 hours of diagnosis; 23% diagnosed within 3 days of onset. However, only 2.3% fogging activities were done within 5 days of o