Table 1 Overview of findings on dengue disease surveillance, vector control, epidemic preparedness and outbreak response

National guidelines, obligatory notification

All study countries had guidelines for surveillance and obligatory notification of suspected and confirmed cases of dengue (in Asia only the severe forms of the disease). No private sector reporting except Brazil and parts of Vietnam

Laboratory confirmation

All Latin American countries attempted 100% confirmation (IgM/IgG); in Asia < 10%

Data transmission

Mainly electronic: Brazil, , Colombia, Dominican Republic, Mexico, Malaysia, Maldives, Sri Lanka (partly) Mainly paper based, partly electronic: Peru, Indonesia, Vietnam, Sri Lanka

Data analysis

At sub-national (state, department, province) and national level. Dominican Republic mainly at national level.

Case classification

Revised WHO classification [5] for clinical management throughout Latin America, Indonesia (partly), Malaysia (partly), Vietnam the others used the dengue fever/dengue haemorrhagic fever/dengue shock syndrome classification.

Active surveillance in sentinel sites

All countries (Maldives only during outbreaks)

Use of alert signals

Most countries collected information on different signals without using it for response (see below)

Routine evaluation of the surveillance system

Weak in all countries except for Brazil, Colombia and Sri Lanka

Organisation of vector surveillance including community involvement

Larval surveys and outbreak alert

Conducted in all countries (Maldives and Vietnam only in sentinel sites). Some indices used for outbreak alert (Peru, Indonesia, Sri Lanka,)

Routine vector control

Larviciding with temephos or Bti (all countries except Indonesia, Maldives, Vietnam)

Vector control issues

Lack of resources, supervision and local involvement in decision making. Vector resistance. Difficult interpretation of entomological indices.

Social mobilisation

All countries use IEC materials, some use the COMBI method

Epidemic preparedness and outbreak response

Outbreak response plans

All countries (except Maldives, Sri Lanka) with varying quality and details

Outbreak response committee

Defined in all countries (except Maldives)

Outbreak definition

Variable definition across countries and in some cases within countries. Some countries with no clear distinction between outbreak and seasonal peak. Several countries use the 2SD of weekly cases above the historical mean or the “moving average” (see text)

Delay of outbreak response

Difficult to assess in most countries due to lack of outbreak definition and delayed reporting. Time lag seems to be usually above 2 weeks but often much longer.

Alert signals and early response

Signals used: entomological indices, increased virus positivity rate, change of serotype, increased case numbers, increased number of fever cases, increased population movement. Information on several signals is collected in some countries but not used for early response because of uncertainty about the validity of the trigger (particularly entomological indices), budget limitations, staff shortage and delay in analysis.

Successful response activities

To a certain extent satisfactory vector control (all countries), improved clinical management, improved coordination (intra-and inter-sectoral) and better information systems (selected countries)

Room for improvement

Improved planning, training, involvement of local staff, enhanced community participation, faster solution of budget constraints, and better cooperation among neighbouring municipalities.

Coping with dengue outbreaks in hospitals (surge capacity)

Positive experiences: Epidemic response plans (in about half of study hospitals); establishing special dengue treatment units; stock-out management (in a few hospitals).

Issues were: getting additional beds and staff, timely resource allocation, stock-out management (particularly intravenous fluids and blood products) and clinical management by untrained staff.