chapter  7
6 Pages

Viral Infections of Circulating Blood Cells

Inclusions in the erythrocytes of Tarentola mauritanica, consisting of reddish dots about 1 µm in diameter that increased to 3-4 µm, circular in shape, and accompanied by globular albuminoid bodies, were designated Pirhemocyton tarentolae by Chatton and Blanc (1914b). Another species, P. lacertae, was recognized by Brumpt and Lavier (1935) in Lacerta viridis. This infection was similar to P. tarentolae, but the albuminoid bodies were not present. Pirhemocyton species designations continued thereafter until 1966, with perhaps the most egregious example that of Rousselot (1953), who assigned seven specific names to infections in West African lizards, apparently on the basis of “different host, therefore different parasite.” Pirhemocyton was generally considered to be a protozoan parasite, perhaps a piroplasm, but Blanc and Ascione (1958) suggested that it might be a type of virus. Stehbens and Johnston (1966) demonstrated that the ultrastructure of a Pirhemocyton in the Australia gecko Gehyra variegata was that of a DNA-type icosahedral virus, similar morphologically to Sericesthis and Tipula iridescent viruses. Even after this clear resolution of its identity, some workers continued to treat Pirhemocyton as a protozoan, notably Arcay de Peraza and de La Roca (1971), whose cytochemical analysis of “Pirhemocyton iguanae” found both RNA and DNA present as well as respiratory activity.