In studies performed in Thailand incidence of DHF/DSS was observed to present mostly in two groups of children: the first group constituted by neonates between 6-9 months of age, infected by a different serotype than the one that infected their mothers, and those in which the maternal antibodies had descended to subneutralizing levels; and the other group formed by children that were previously infected by a DENV serotype and then by a different one.
En estudios realizados en Tailandia se observó que la incidencia de FHD/SSD se presenta mayormente en dos grupos de niños: el primero constituido por neonatos entre 6-9 meses de edad, infectados con un serotipo diferente al que había infectado a sus madres, y en quienes los anticuerpos maternos ya habían descendido a niveles subneutralizantes; y otro grupo compuesto por niños que habían estado previamente infectados con un serotipo de DENV y luego con uno diferente.