Enhanced severity of secondary dengue-2 infections: death rates in 1981 and 1997 Cuban outbreaks

Abstract

We found a marked increase in severity with the longer of the two intervals (20 years) between an initial DEN-1 infection and a secondary DEN-2 infection. Such a difference may be due to subtle shifts in causative dengue strains or to changes with the passage of time in the circulating population of human dengue antibodies. These observations have important implications for dengue control, pathogenic mechanisms, and vaccine development.