Dengue Sentinel Surveillance System in Countries Without Efficient Local Epidemiological Surveillance


To the Editor-in-Chief

The surveillance of travel-acquired dengue infections in French military personnel[1] or others could be strengthened through an inclusion of a local laboratory (civilian or military)-based surveillance for dengue-associated laboratory parameters. The laboratory personnel could be on the lookout for any suspected dengue infections in the samples received for performing complete blood counts. They could select those with platelet counts less than 100 × 103/μL (100 × 109/L) and/or circulating anti-dengue virus IgM and IgG and offer valuable information to clinicians and public health agencies.

Such a strategy would be an asset even in remote locations because facilities for carrying out complete blood counts are readily available in every clinical laboratory. Moreover, a confirmation would be feasible even in cases with a primary or secondary infection by employing a point-of-care assay format for simultaneous detection of dengue nonstructural protein 1 (NS1) antigen, IgM and IgG. Such a testing was useful during the 2010 outbreak of dengue in Delhi. There were 86 NS1-positive cases and 89 NS1-negative cases. NS1 positives included 57 that were negative for IgM and 4 that were positive for IgG. Of these 61 patients, 57 with a primary infection and 4 with a secondary infection would otherwise be labeled as negative.[2]

  • Subhash C. Arya and Nirmala Agarwal

  • Sant Parmanand Hospital, Delhi, India