Fig 1.

Clinical course of dengue hemorrhagic fever. Clinical events and laboratory findings during phases of illness from the febrile phase through the critical phase and into the recovery phase is shown. Hemoconcentration (an increase in hematocrit) occurs during the critical phase and is an indication of plasma leakage. Platelet counts decline during the illness reaching the lowest point around the time when plasma leakage occurs. Shaded areas represent the normal ranges for temperature, hematocrit, and platelet count.