Why are protozoan infections hard to treat

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Medchemcomm 6, — World Health Organization Control and surveillance of human African trypanosomiasis. World Health Organ. However, drug resistance is not an all-or-nothing proposition, and the answer to the Sphinx's riddle is that the parasites remain sensitive but that the parasite clearance time is significantly increased in the adapted strains [ 42 ].

The K13 mutations have the effect of shortening the duration of the trophozoite stage, during which the parasite is particularly susceptible to artemisinin, and lengthening the duration of the ring stage that is relatively insensitive due its low haem content [ 47 ]. This adaptation of intra-erythrocyte development is yet another unimagined way by which parasites can develop clinical resistance, but the clinical resistance would probably not have taken hold if the ACT partner drugs had not suffered from resistance first.

This is not a trivial concern, as we truly cannot lose any of the main anti-protozoal drugs, and should feature in current discussions about the potential introduction of combinations against visceral leishmaniasis. Resistance against all the major anti-leishmanial drugs has been reported [ 16 , 48 , 49 ] and, alarmingly, resistance against several combinations can be induced readily in vitro [ 50 ].

In conclusion, we see that it is extremely difficult to prevent the onset, or spread of drug resistance and that, therefore, the reality is that we are and will continue to lose life-saving treatments.

While more can be done on the side of prevention, vector control, sanitation, etc. For that, genuine, long-term partners with very deep pockets are eagerly sought. Sign In or Create an Account. Advanced Search. Sign In. Skip Nav Destination Article Navigation. Close mobile search navigation Article navigation. Volume 1, Issue 6. Issue Editors. Roberto Docampo Roberto Docampo. This Site. Google Scholar. Previous Article Next Article.

All Issues. Cover Image Cover Image. Competing Interests. Article Navigation. Perspective December 22 Drug resistance in protozoan parasites Harry P. Correspondence: Harry P. Emerg Top Life Sci 1 6 : — Article history Received:. Revision Received:. Get Permissions. The Author declares that there are no competing interests associated with this manuscript. Search ADS. Field evaluation of two different treatment approaches and their ability to control fleas and prevent canine leishmaniosis in a highly endemic area.

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