African Mammalian Trypanosomiasis

Human trypanosomiasis (Trypanosoma brucei gambiense), EATRO, Uganda

Haematocrit Centrifuge Technique, trypanosomiasis survey (human), SRI, Tanzania

Bovine trypanosomiasis (Trypanosoma congolense), EATRO, Uganda

His first research program was on trypanosomes and trypanosomiasis in animals including humans, and a major component of his research in Africa was on the diagnosis of human trypanosomiasis. He successfully used the Haematocrit Centrifuge Technique (HCT; Woo, 1969) to detect trypanosomes in the blood and cerebral spinal fluid of patients suffering from Rhodesian and Gambian trypanosomiases. The study was conducted in the hospital attached to the East African Trypanosomiasis Research Organization (EATRO), Uganda(Woo, 1970). He then adapted HCT for use under field conditions and conducted a survey in the Lugala area, Uganda; 413 people were examined in a single day, and trypanosomes were detected in one person (with no clinical signs of the disease) and microfilariae in 17 other people (Woo, 1971). Feasibility of HCT as a field technique was confirmed in a much larger survey on human trypanosomiasis in Musoma district, Tanzania (Onyango & Woo, 1971).

"The . . . technique of Woo is the most suitable for rural hospitals" (Foulkes, 1981). It " . . . is still in use in many HAT [Human African Trypanosomiasis] control programs" in Africa (Chappuis et al., 2005), and " . . . is the test of choice since it concentrates trypanosomes at the buffy coat area where they can be located by microscopy" (Matovu E. et al. 2012). HCT is also used to diagnose human African trypanosomisis outside of Africa (e.g. Lejon et al., 2003), for the detection of congenital Trypanosoma cruzi infection in Argentina (Moretti et al. 2005), and it is ". . . recommended for the parasitological diagnosis of acute Chagas' disease and malaria" in rural Bolivia (Fuente et al., 1985).

Woo & Kauffmann (1971) showed that HCT could also be used as a field technique to detect low virulent strains of Trypanosoma congolense in wild animals (e.g. lions); this was part of a field study to determine the epidemiology of trypanosomiasis in the Serengeti National Park. Tanzania. HCT is a rapid and sensitive technique for the detection of trypanosomes (Trypanosoma brucei brucei, T. brucei rhodesiense, T. evansi, T. congolense) under laboratory conditions (Woo & Rogers, 1974) and it is " . . . most commonly used for the diagnosis of animal trypanosomiasis . . . " (Desqquesnes & Tresse 1996). It is recommended by the‘International Office of Epizootics' (OIE 2013 - Table 1), and Moti et al. (2014) confirms that "HCT remains a robust field method as it will be more efficient than PCR to detect clinical cases that have to be treated". The technique can also be used to determine the effectiveness of chemotherapy against trypanosomiasis (e.g. Sekoni & Rekwot 2003).

The Haematocrit Centrifuge Technique is frequently used/cited in studies on trypanosomes and trypanosomiasis (e.g. in Google Scholar, Semantic Scholar), and it is sometimes also called the:
"Woo test", e.g. (i) Chappuis F et al. 2005,Options for field diagnosis of human African trypanosomiasis. Clinical Microbiol. Reviews 18: 133-146
    (ii) Desquesnes M & Tresse L1999, Sensitivity of the Woo test for detection of Trypanosoma vivax. Proceedings of First Symposium o New World Trypanosomes, pp. 76-81.
"Woo technique", e.g.(i) Quispe AP et al. 2003, Prevalencia de Trypanosoma vivax en bovinos de cuatro distritos de la provincia de Coronel Portillo, Ucayali. Rev investig. vet. Peru 14: 161-165
    (ii) Cadioli FA et al. 2012First report of Trypanosoma vivax outbreak in dairy cattle in Sao Paulo, Brazil. Rev. Bras. Parasitol. Vet. Sao Paulo 21: 118-124
"Woo method", e.g. (i) Uilenberg G 1998, Chapter 3 - Diagnosis. In: A field guide for the diagnosis, treatment and prevention of African animal trypanosomosis, FAO, UN, 158 pages
    (ii) OIE 2013, Chapter 2.4.17 - Trypanosomosis (tsetse-transmitted). In: OIE Terrestrial Manual, pp. 1-11.

33. Woo, P.T.K. 2004. The pathophysiology of salmonid cryptobiosis and Glossina-transmitted mammalian trypanosomiasis in livestock. Symp. Soc. Exp. Biol. 55: 91-105.

32. Woo, P.T.K. 1991. Piscine cryptobiosis and mammalian trypanosomiasis in North America. Bull. Soc. Vector Ecology 16: 25-42.

31. Otigbuo, I.N. & Woo, P.T.K. 1988.The in vitro and in vivo effects of metronidazole and chloroquine on Trypanosoma brucei brucei. J. Parasit.74: 201-206.

30. Otigbuo, I.N. & Woo, P.T.K. 1987.Trypanosoma b. brucei: A culture medium reverting a monomorphic to a pleomorphic strain. Trans. R. Soc. Trop. Med. Hyg. 81:408-410.

29.Soltys, M.A. &Woo, P.T.K. 1977. Trypanosomes producing disease in livestock in Africa. In: Parasitic Protozoa, Volume 1 (ed. J.P. Kreier), Academic Press, New York, U.S.A., pp.239-268.

28.Woo, P.T.K. 1977. Salivarian trypanosomes producing disease in livestock outside subsaharan Africa. In: Parasitic Protozoa, Volume 1 (ed. J.P. Kreier), AcademicPress, U.S.A., pp. 269-296.

27. Kobayashi, A., Soltys, M.A. &Woo, P.T.K. 1976. Comparative studies on the laboratory diagnosis of experimental Trypanosoma congolense in sheep. Ann. Trop. Med.Parasit. 70: 53-59.

26. Kobayashi, A., Tizard, I. & Woo, P.T.K. 1975. Studies on the anaemia in experimental African trypanosomiasis. II. The pathogenesis of the anaemia in calves infected with Trypanosoma congolense. Amer. J. Trop. Med. Hyg. 25: 401-407.

25. Woo, P.T.K. & Hawkings, J.D.1975. Trypanosomes and experimental trypanosomiasis in East African bats. Acta Tropica 32: 57-64.

24. Woo, P.T.K. & Kobayashi, A. 1975.Studies on the anaemia in experimental African trypanaosomiasis. I. A prliminary communication of the mechanism of the anaemia. Ann. Soc. Belg. Med.Trop. 55: 37-45.

23. Woo, P.T.K. 1974. A review of studies on the immunization against the pathogenic protozoan diseases of man. Acta Tropica 31: 1-27.

22. Woo, P.T.K. & Rogers, D. 1974. A statistical study on the sensitivity of the haematocrit centrifuge technique inthe detection of trypanosomes. Trans. R. Soc. Trop. Med. Hyg. 68: 319-326.

21. Soltys, M.A. & Woo, P.T.K. 1973.Indirect charcoal agglutination test in the diagnosis of Sleeping Sickness in West Africa. Z. Tropenmed. Parasit. 24: 143-145.

20. Soltys, M.A., Thomson, S.M.R. &Woo, P.T.K. 1972. Experimental transmission of Trypanosoma bruceiand T. congolense in rats and guinea pigs through intact mucous membrane and skin. Ann. Trop. Med. Parasit. 67: 399-402.

19.Soltys, M.A. &Woo, P.T.K. 1972. Immunological methods in diagnosis of protozoan diseases in man and domestic aniamls. Z. Tropenmed. Parasit. 23: 173-187.

18.Tizard, I.R., Woo,P.T.K. & Soltys, M.A. 1972. Immunological techniques in the diagnosis of protozoan diseases in domestic animals. In: 76th Annual Meeting, U.S. Animal Health Association, pp. 758-768.

17.Woo, P.T.K. &Soltys, M.A. 1972a. The indirect haemagglutination and charcoal aggultination tests in the diagnosis of African sleeping sickness. Z. Tropenmed. Parasit. 23:324-327.

16. Woo, P.T.K. & Soltys, M.A. 1972b.Indirect haemagglutination test with sera of animals experimentally infected with Trypanosoma brucei and Trypanosoma rhodesiense.Z. Tropenmed. Parasit. 23: 166-172.

15. Onyango, R.J. & Woo, P.T.K. 1971.Sleeping Sickness survey in Musoma District, Tanzania. I. Investigation of the incidence of sleeping sickness in the human population. Acta Tropica 28: 181-189.

14.Soltys, M.A., Woo,P.T.K. & Gillick, A.C. 1971. Differences in size between forms of trypanosomes in blood and in organs. In: Pathology of Parasitic Diseases (eds. S.M. Gaafar, G.M. Urquhart, J. Euzeby, E.J.L. Soulsby &G. Lammler), Purdue University Press, Indiana, U.S.A., pp. 15-18.

13. Woo, P.T.K. 1971a. Evaluation of the haemataocrit centrifuge and other techniques for the field diagnosis of human trypanosomiasis and filariasis. Acta Tropica 28: 298-303.

12. Woo, P.T.K. 1971b. A technique for the parasitological diagnosis of African trypanosomiasis. Trans. R. Soc. Trop. Med. Hyg. 65: 249- 250.

11. Woo, P.T.K. & Kauffman, M. 1971.The haematocrit centrifuge technique for the detection of low virulent strains of trypanosomes of the Trypanosoma congolense sub-group. Acta Tropica 28: 304-308.

10.Woo, P.T.K. &Soltys, M.A. 1971. The effects of suramin on blood and tissue stages of Trypanosomabrucei and T. rhodesiense. Ann. Trop. Med. Parasit. 65:465-469.

9.Soltys, M.A. &Woo, P.T.K. 1970a. Further studies on tissue forms of Trypanosoma bruceiin a vertebrate host. Trans. R. Soc. Trop. Med. Hyg. 64: 692-694.

8.Soltys, M.A. &Woo, P.T.K. 1970b. Biological differences of two sub- strains of Trypanosomabrucei maintained by syringe passage in two different hosts. Ann. Trop.Med. Parasit. 64: 249-254.

7.Woo, P.T.K. &Soltys, M.A. 1970. Animals as reservoir host of human trypanosomes. In:Annual Wildlife Disease Association Annual Conference (eds. L. Karstad, J.Budd, P.F. Olsen & G. Hoffman) 6: 313-322.

6. Woo, P.T.K. 1970a. Origin of mammalian trypanosomes which develop in the anterior-station of blood-sucking arthropods. Nature 228: 1059-1062.

5. Woo, P.T.K. 1970b. The haematocrit centrifuge technique for the diagnosis of African trypanosomiasis. Acta Tropica27: 384-387.

4. Soltys, M.A., Woo, P.T.K. &Gillick, A.C. 1969. A preliminary note on the separation and infectivity oftissue forms T. brucei. Trans. R. Soc. Trop. Med. Hyg. 63:495-496.

3. Soltys, M.A. & Woo, P.T.K. 1969a.Multiplication of Trypanosoma brucei and Trypanosoma congolensein vertebrate hosts. Trans. R. Soc. Trop. Med. Hyg. 63: 480-485.

2. Woo, P.T.K., & Soltys, M.A.1969b. The experimental infection of reptiles with Trypanosoma brucei. Ann. Trop. Med. Parasit. 63: 35-38.

1. Soltys, M.A. & Woo, P.T.K. 1968. Leeches as possible vectors for mammalian trypanosomes. Trans. R. Soc. Trop.Med. Hyg. 62: 154- 156.