Organisms exclusively extracellular in the gut of, and non-pathogenic for, the human- body louse, which acts as the vector of this agent of trench fever. The type species of the subgenus is Rickettsia quintana Schmincke. 8. Rickettsia quintana Schmincke, 1917. (Schmincke, Miinch. med. Wochnschr., 64, 1917, 961; Rickettsia pediculi Munk and da Rocha-Lima, Miinch. med. Wochnschr., 64, 1917, 1423; Rickettsia wolhynica Jungmann and Kuczynski, Ztschr. f. klin. Med., 85, 1918, 261; Rickettsia weigh Mosing, Arch. Inst. Past., Tunis, 25, 1936, 380; Burnetia (Rocha-Ldmae) wolhijnicaMeLCchiaveWo, Prim. Reunion Interamer. del Tifo, Mexico, 1947, 410; Burnetia (Rocha-Limae) weigli Macchia- vello, loc. cit.; Wolhynia quintanae (sic) Zhdanov and Korenblit, Jour Microbiol., Epidemiol, and Immunobiol. (Russian), No. 9, 1950, 42.) quin.ta'na. M.L. adj. quintanus fifth; referring to five-day fever, one of the collo- quial names of the fever caused by this species. Coccoid or ellipsoidal organisms, often occurring in pairs. More plump and stain more deeply with Giemsa's stain than does R. prowazekii. 0.2 to 0.4 micron (da Rocha- Lima). In lice, appear as short rods, fre- quently occurring in pairs and often bi- polarly stained. Occur extracellularly in the . region of the epithelial lining of the lumen of the gut of the louse. Non-motile. Stain reddish violet with Giemsa's stain. Gram- negative. Cultivation: Has not been cultivated in tissue culture, yolk sacs of chick embryos or any other cell-free medium (report of cultivation of Rickettsia pediculi and R. rochalimae, which are regarded as identical with this species, on cell-free media remains to be confirmed). Grows in body lice in- jected intrarectally or fed on patients, but unlike most other Rickettsia spp., it was not found to grow in living meal-worm larvae (Weyer, Acta Tropica, 11, 1954, 207). Serology: Possesses no common antigenic factor with Proteus strains. No practical serological procedure has been developed, though louse guts and louse feces have been reported to provide antigens for agglutina- tion tests. Laboratory diagnosis, therefore, additional to clinical and epidemiological data, is largely dependent for confirmation on the demonstration of extracellular rickettsiae in carefully selected louse stocks fed either during the human febrile episode or later. Pathogenic for man, causing rash and re- current fever. Blood of cases has been shown to be infectious on transfer to volunteers as long as 4, 5 and even 8 years following clini- cal recovery. Mooser and his colleagues, among others, have repeatedly infected lice fed during such periods of latency in ap- parently healthy persons. Man, therefore, is the obvious reservoir of the infection. Codeleoncini infected the baboon, and Mooser and Weyer found rhesus monkeys susceptible. Immunology: Partial immunity is pro- duced after an attack of the disease. The disease is characterized by relapses which may occur as long as 2 to 3 years after the initial attack. Distinctive characters : Resists a tempera- ture of 60° C. moist heat for 30 minutes or a dry heat of 80° C. for 20 minutes. Resists desiccation in simlight for 4 months. Has been filtered under certain conditions but not when in plasma or serum. Present in filtrates of infected vaccine sediments and for long periods in the feces of infected lice. Intracutaneous injection of living organisms from lice produces skin lesions in the rabbit which can be inhibited by the use of conva- lescent serum. Source: Observed in lice fed on trench- fever patients by Topfer (Miinch. med. Wochnschr., ei, 1916, 1495). Habitat: Found in the epithelial lining of the gut of the body louse (Pediculus hu- manus var. humanus) where the rickettsiae occur extracellularly; also found in P. humanus var. capitis. Not transmissible through the ova. The etiological agent of trench fever (Wolhynian fever, shin-bone fever, five-day fever). Addendum: Two pathogenic agents of importance in the U. S. S. R. have come to attention since this section was prepared:
