Fig. 25.—Prowazekia urinaria. Flagellate emerging from cyst. (After Sinton.)
In cultures Prowazekia urinaria was always found in association with bacteria. The cultures died at a temperature of 37° C., but grew well at 20° C. Various media were useful at the lower temperature, such as urine, salt agar, nutrient agar, serum agar, blood agar, peptone salt solution, and diluted blood serum. The flagellate was, then, considered to be an accidental contamination and not a true parasite of human urine.
Prowazekia asiatica, Castellani and Chalmers, 1910.
The flagellate was found by the discoverers in the stools of patients suffering from ankylostomiasis and diarrhœa in Ceylon. It was referred by them to the genus Bodo, but in 1911 Whitmore[49] further studied it and placed it in the genus Prowazekia. In the stools the flagellate is found either as a long, slender form measuring 10 µ to 16 µ by 5 µ to 8 µ or as a rounded form 8 µ to 10 µ in diameter. Its cytoplasm is alveolar. A rhizoplast connects the basal granules to the kinetic nucleus. There is multiplication and cyst formation as before. The organism is easily cultivated, especially in the condensation water of nutrose agar and maltose agar. The pathogenicity is stated to be nil.
Prowazekia javanensis, Flu, 1912.
Found in agar cultures from the motions of patients at Weltevreden, Dutch East Indies.[50] The flagellates are 12 µ long and 5 µ broad. The lateral flagellum is stated to be attached to the cell body for a short distance. Regarding the karyosome in the nucleus, the author states that the smaller the karyosome the more chromatin is deposited on the nuclear membrane. Flu mentions that the specific name javanensis is a temporary one, as in the course of time it may be shown that there is only one species of Prowazekia.
Prowazekia cruzi, Hartmann and Chagas, 1910.
Found in a culture from human fæces on an agar plate in Brazil, and considered to be a free-living form.[51] The organism is oval or pear-shaped, 8 µ to 12 µ long and 5 µ to 6 µ broad. In human stools at Tsingtau, China, a Prowazekia has been found by Martini which he thinks is the same as Prowazekia cruzi. He considers it to be a cause of human diarrhœa and intestinal catarrh.