Detection and preliminary studies of small double capsid virus

This article reports the detection of small double capsid virus and results of preliminary studies on its morphology, serology and relationship to gastroenteritis. A kind of small virus particles with morphological characteristics was found in fecal samples of 3 of 23 infants with autumn gastroenteritis. The average diameter of this virus particles is 34.1 +/- 1.1 nm, possessing core, double capsids and spoke-like capsomers. It can be differentiated from other viruses in morphology. Correlated antigenicity exists among 3 strains of the virus but not among other studied viruses and this virus. The titer of the antibody to small double capsid virus in convalescent phase-sera of 2 patients was more than 4-fold as high as that in control sera. This virus was absent in fecal samples of recovered patients as well as in those of normal infants. These show that small "double layer like" capsid virus might be one of the etiological agents of acute gastroenteritis.