Pharma to farmer: field challenges of optimizing trypanocide use in African animal trypanosomiasis

Control of African animal trypanosomiasis (AAT) is hampered by limited diagnostics, inappropriate trypanocide use, poor drug quality, and resistance.The scope quality current literature on AAT incidence, control, resistance does not allow for robust comparisons or assessment the validity extrapolating to other populations.A united effort needed address at local, national, international settings ensure a greater chance success.AAT control programmes must be sustainable through funding, cross-sectoral engagement, fostering behavioural change incentives accountability. Trypanocides are key component in tsetse-infested areas sub-Saharan Africa. While farmers dependent upon trypanocides, recent research highlights their ineffective problems with treatment failure. There currently gaps knowledge investment inexpensive understanding resistance, effective use trypanocides field. Without this important it difficult develop best practice policy existing drugs inform development new drugs. needs better drivers practices around so that they can incorporated into solutions AAT. (see Glossary) an constraint livestock production parts Africa (SSA) where tsetse fly vector found. Improving food security, whilst potential impacts risk human (HAT) highlight its value as One Health intervention [1.Fyfe J. et al.Impact mass chemotherapy domestic zoonotic T. b. rhodesiense Eastern Uganda.Acta Trop. 2017; 165: 216-229Crossref PubMed Scopus (11) Google Scholar, 2.Lord J.S. al.Assessing effect insecticide treated cattle abundance trypanosome transmission wildlife-livestock interface Serengeti, Tanzania.PLoS Negl. Dis. 2020; 14e0008288Crossref (3) 3.Informal Expert Group Gambiense HAT Reservoirs Do cryptic reservoirs threaten Gambiense-sleeping sickness elimination?.Trends Parasitol. 2018; 34: 197-207Abstract Full Text PDF (71) Scholar]. (Box 1) Whilst review [4.Giordani F. al.The trypanosomiases chemotherapy: review.Parasitology. 2016; 143: 1862-1889Crossref (172) Scholar] described antitrypanosomal chemotherapy, there urgent need consider our how these widely available used This improve drugs; timely because issues relevant implementation under development. paper reviews usage, effectiveness, identifies barriers optimal order make recommendations regarding future use.Box 1Trypanocides treat prevent ruminantsThere three ruminants: diminazene aceturate (DZ), isometamidium chloride (ISM), homidium salts (HM – also known ethidium bromide). range doses medications, packaging retail sale typically only one dose listed.DZ was introduced 1955 curative therapy. It administered intramuscular (IM) subcutaneous (SC) route 3–5 mg/kg DZ usually sold single-dose sachets powder diluted sterile water.ISM 1960s given via deep IM injection prophylaxis 0.25–1 labelled Administration associated lesions site injection, especially long-term use. If IV, prophylactic effects negated, whereas administration results 2–6 month period. ISM multi- sachet water.HM 1952 IV small ruminants 1 proven mutagenic possible carcinogenic discouraged HM have some properties but less than ISM. tablet form ground water.Quinapyramine between 1950 1970 removed from market due toxicity Despite this, several species, including cattleiii,iv, although extent clear. listed. water. Quinapyramine The direct indirect options summarized Meyer al. 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