152 KEVIEW — TROPICAL MEDICINE, ETC. 



Bovine It sometimes happens, however, that animals in an infected area die before Piroplasma parvum has developed 



piro- to any extent, and in such cases the diagnosis must remain doubtful. Bubertson has found that East Coast fever 



I • may run its course with a total absence of P. parvum in the peripheral blood, or perhaps only with the presence 



" . of a very small number of these parasites. In such cases a post mortem examination is the only way of enabling 



contmuM Qjjg jQ iorm a correct diagnosis. Since, however, P. parvum does not always produce the typical lesions (infarcts 

 in the liver, etc.), even this procedure may be useless. 



It will be remembered that, in the case of East Coast fever, transmission by the bite of the progeny of ticks 

 fed on sick animals, always failed to infect ; but infection taken in by the larvfe was transmitted by the nymph, 

 and that taken in by the nymph was transmitted by the adult (Lounsbury and Theiler). 



Quite recently Fulleborn^* has found cross-shaped divisional forms in P. hovis, so that 

 these can no longer be regarded as characteristic of F. parvum and allied species. 



A condition likely to be of interest to veterinarians in the Sudan, is that ascribed 

 by Kowalewski- to an atypical form of piroplasmosis, which seems really to be the latter 

 disease complicated with rinderpest, as is evidenced by the post mortem findings. In 

 endeavouring to differentiate the disease from others, the following points should be 

 borne in mind : — 



1. The epithelium surrounding the erosions and small swellings on the under lip is firmer, and cannot so 

 easily be rubbed off as in rinderpest. 



2. In jjiroplasmosis the small swellings are firmer, white in colour, isolated, and are not covered with a 

 caseous material as in rinderpest. 



3. In piroplasmosis cases are observed where no swellings whatever exist, but only numerous little erosions. 



4. The enlargement and softening of the spleen, which only occurs exceptionally in rinderpest. 

 6. Very characteristic ochre-like coloration of the liver. 



6. Haemorrhagic processes in the kidneys ; and 



7. In a few cases, blood-stained urine. 



Of very considerable importance, if it be confirmed, is the announcement by Miyajima' 

 that he has succeeded in cultivating a bovine piroplasm found in Japanese cattle, and 

 apparently identical with P. parvum, because in vitro the parasites took on the trypanosome 

 form. The simple method employed is as follows :— 



The blood containing intracellular parasites is drawn from the jugular vein and then quickly dcfibrinated 

 under strict precautions so as to avoid bacterial contamination ; it is then directly mixed with ordinary nutrient 

 bouillon, in proportions varying from one-fifth to one-tenth, and placed aseptically in sterile test-tubes, which 

 thereafter are maintained at a temperature of 20° C. to 30" C. The development of the parasites in a successful 

 culture takes place in the following manner ; On the first day no motile form is seen ; on the second, there can be 

 observed a certain number of peculiar cells, which occupy the upper layer of sedimeuted corpuscles and which 

 macroscopically appear as a series of whitish dots. Very few motile forms resembling typical trypauosomata are 

 visible in these cells on the third day after incubation, but thereafter the trypanosomata multiply vigorously and 

 reach the maximum number between the tenth and fourteenth days. 



In a culture kept at room temperature, the trypanosomata remain motile until forty-five days later ; at this 

 time most of them have undergone degeneration and globular cells with irregular granulations result. In a culture 

 preserved at a lower temperature, ranging fi-om 10° C. to 20° C, the organism on the contrary remains alive until 

 three months after the maximum number has been reached. It is noteworthy that subcultures are also readily 

 obtained by inoculating from the original strain into a new blood bouillon, as in the case of Tryjmnosoma Icwisi. 



The most important factor in securing the multiplication of the parasites essentially consists in great 

 precautions in avoiding the slightest contamination with bacteria, as is the case with other cultures of ijrotozoa. 



With reference to preventive measures, Captain Olver kindly furnished me with the 

 following particulars regarding the rationale and carrying out of Stockmann's method, 

 which, associated with the paying of appropriate indemnities, has proved very successful in 

 South Africa : — ■ 



1. East Coast Fever is conveyed by ticks only, and no other animals except cattle appear to be susceptible. 



2. Cattle which have recovered from an attack do not harbour the parasite, and consequently are incapable 

 of acting as permanent centres of infection. 



3. Infected ticks clean themselves and are incapable of infecting susceptible cattle afterwards, by feeding on 

 non-susceptible animals. 



Consequently, if a farm is kept free of all cattle for a sufficiently long period to allow all existing ticks to go 

 through a complete life-cycle the disease dies out and will not re-appear unless re-introduced from outside. 

 Fortunately ticks do not travel far unless carried. 



In South Africa, where the system was successfully applied in practice, the period was arbitrarily fixed at 

 14 months, but it is probable that even less would be sufficient. 



» Fiilleborn (1908). Arch.fiir Schiffs. und Tropin. Hyg., Bd. XII. 



' Kowalewski.I. M. (June, 1907), "Clinical and Anatomical Appearances of the Atypical Form of Piroplasmosis." 

 Quoted in Journal of Comparative Palholoyy and Therapeutics, Vol. XX. 



■■' Miy<ajima, M. (May, 1907), "On the Cultivation of a Bovine Piroplasma." Philippine Jom-nal of Science, 

 Vol. II., B. Med. Sc. 



• Article not consulted in the original. 



