Dengue surveillance in Metro Manila.

In a one-year surveillance of dengue infection in four hospitals in Metro Manila, Philippines, 143 patients were enrolled. Sixty seven were diagnosed by virus isolation and serology. Majority of patients had secondary antibody response. Only 5 patients developed dengue shock syndrome. Only dengue types 1 and type 2 were isolated. Highest incidence occurred among older children and young adults. Thrombocytopenia and hemoconcentration were observed in 37% and 77% of patients, respectively. There was no fatality. Several problems were identified in the course of the study which need to be corrected in order to have good quality surveillance data in future undertakings.