Effective surveillance of dengue cases is essential:
- To detect outbreaks in order to initiate timely and effective control measures;
- Monitor the trends of incidence including temporal and geographic distribution of cases;
- To monitor number of severe dengue cases and deaths;
- To assess and confirm possibility of outbreaks based on serological evidence;
- To monitor the impact of control interventions.
Epidemiological surveillance requires the report on the following indicators
- Suspected (clinical) cases of dengue and severe dengue;
- Confirmed (laboratory-tested) cases of dengue and severe dengue;
- Circulating serotypes (DEN-1,-2,-3 or -4);
- Number of deaths from dengue or severe dengue;
- Number of deaths among severe dengue cases, suspected or confirmed.
The effective prevention and control of epidemic dengue requires an active laboratory-based disease surveillance programme (using serological and virological diagnosis) that can provide early warning of impending epidemic transmission. However, for early detection of suspected cases, routine monitoring of fever cases in sentinel sites should be considered.