Dengue virus replication in mosquito cell cultures was observed by
electron microscopy in one fatal and 40 classical isolates from a dengue
type 2 outbreak in Rio de Janeiro and compared with the prototype New Guinea
C strain. All the Brazilian isolates presented, beside the classical
structured dengue virus particles, fuzzy coated virus-like particles, never
observed in the referencial New Guinea C virus strain. More numerous DEN-2
virus particles, fuzzy coated virus-like particles, defective virus particles
and smooth membrane structures inside the rough endoplasmic reticulum
characterized the unique fatal isolate examined.