Introduction
They are medium-sized (70 – 90nm), non-enveloped, icosahedral (252 capsomeres, 240 hexameres, 12 pentameres)
viruses with a linear double-stranded DNA. Each pentamere of the virus has a protein fiber with a knob on it. This fiber
determines the tropism of that adenovirus and determines what kinds of cells will be affected because this fiber has
attachment proteins for different organs in our body systems.
There are many serotypes and groups of adenoviruses with a broad spectrum of clinical manifestations. In the
adenovirus family we are concerned with the genus Mastadenovirus which cause human infections. This virus has been
accidentally isolated from adenoid tissue in 1953. The family of adenoviridae has been divided into six subgroups (A-F)
according to the hemagglutination characteristic feature of the virus. In every subgroup we have different serotypes
according to the antigenic determinant of the virus. The subgroup F (serotypes 40, 41) is called enteric adenoviruses that
cause gastroenteritis.