Tsetse Control and Gambian Sleeping Sickness; Implications for Control Strategy.
BACKGROUND:Gambian sleeping sickness (human African trypanosomiasis, HAT) outbreaks are brought under control by case detection and treatment although it is recognised that this typically only reaches about 75% of the population. Vector control is capable of completely interrupting HAT transmission...
| Main Authors: | , , , , , , , , |
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| Format: | Article |
| Language: | English |
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Public Library of Science (PLoS)
2015-01-01
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| Series: | PLoS Neglected Tropical Diseases |
| Online Access: | http://europepmc.org/articles/PMC4580652?pdf=render |
| _version_ | 1819041241892913152 |
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| author | Inaki Tirados Johan Esterhuizen Vanja Kovacic T N Clement Mangwiro Glyn A Vale Ian Hastings Philippe Solano Michael J Lehane Steve J Torr |
| author_facet | Inaki Tirados Johan Esterhuizen Vanja Kovacic T N Clement Mangwiro Glyn A Vale Ian Hastings Philippe Solano Michael J Lehane Steve J Torr |
| author_sort | Inaki Tirados |
| collection | DOAJ |
| description | BACKGROUND:Gambian sleeping sickness (human African trypanosomiasis, HAT) outbreaks are brought under control by case detection and treatment although it is recognised that this typically only reaches about 75% of the population. Vector control is capable of completely interrupting HAT transmission but is not used because it is considered too expensive and difficult to organise in resource-poor settings. We conducted a full scale field trial of a refined vector control technology to determine its utility in control of Gambian HAT. METHODS AND FINDINGS:The major vector of Gambian HAT is the tsetse fly Glossina fuscipes which lives in the humid zone immediately adjacent to water bodies. From a series of preliminary trials we determined the number of tiny targets required to reduce G. fuscipes populations by more than 90%. Using these data for model calibration we predicted we needed a target density of 20 per linear km of river in riverine savannah to achieve >90% tsetse control. We then carried out a full scale, 500 km2 field trial covering two HAT foci in Northern Uganda to determine the efficacy of tiny targets (overall target density 5.7/km2). In 12 months, tsetse populations declined by more than 90%. As a guide we used a published HAT transmission model and calculated that a 72% reduction in tsetse population is required to stop transmission in those settings. INTERPRETATION:The Ugandan census suggests population density in the HAT foci is approximately 500 per km2. The estimated cost for a single round of active case detection (excluding treatment), covering 80% of the population, is US$433,333 (WHO figures). One year of vector control organised within the country, which can completely stop HAT transmission, would cost US$42,700. The case for adding this method of vector control to case detection and treatment is strong. We outline how such a component could be organised. |
| first_indexed | 2024-12-21T09:21:52Z |
| format | Article |
| id | doaj.art-37f83d10d8b341dfba55bac038e47f6c |
| institution | Directory Open Access Journal |
| issn | 1935-2727 1935-2735 |
| language | English |
| last_indexed | 2024-12-21T09:21:52Z |
| publishDate | 2015-01-01 |
| publisher | Public Library of Science (PLoS) |
| record_format | Article |
| series | PLoS Neglected Tropical Diseases |
| spelling | doaj.art-37f83d10d8b341dfba55bac038e47f6c2022-12-21T19:08:59ZengPublic Library of Science (PLoS)PLoS Neglected Tropical Diseases1935-27271935-27352015-01-0198e000382210.1371/journal.pntd.0003822Tsetse Control and Gambian Sleeping Sickness; Implications for Control Strategy.Inaki TiradosJohan EsterhuizenVanja KovacicT N Clement MangwiroGlyn A ValeIan HastingsPhilippe SolanoMichael J LehaneSteve J TorrBACKGROUND:Gambian sleeping sickness (human African trypanosomiasis, HAT) outbreaks are brought under control by case detection and treatment although it is recognised that this typically only reaches about 75% of the population. Vector control is capable of completely interrupting HAT transmission but is not used because it is considered too expensive and difficult to organise in resource-poor settings. We conducted a full scale field trial of a refined vector control technology to determine its utility in control of Gambian HAT. METHODS AND FINDINGS:The major vector of Gambian HAT is the tsetse fly Glossina fuscipes which lives in the humid zone immediately adjacent to water bodies. From a series of preliminary trials we determined the number of tiny targets required to reduce G. fuscipes populations by more than 90%. Using these data for model calibration we predicted we needed a target density of 20 per linear km of river in riverine savannah to achieve >90% tsetse control. We then carried out a full scale, 500 km2 field trial covering two HAT foci in Northern Uganda to determine the efficacy of tiny targets (overall target density 5.7/km2). In 12 months, tsetse populations declined by more than 90%. As a guide we used a published HAT transmission model and calculated that a 72% reduction in tsetse population is required to stop transmission in those settings. INTERPRETATION:The Ugandan census suggests population density in the HAT foci is approximately 500 per km2. The estimated cost for a single round of active case detection (excluding treatment), covering 80% of the population, is US$433,333 (WHO figures). One year of vector control organised within the country, which can completely stop HAT transmission, would cost US$42,700. The case for adding this method of vector control to case detection and treatment is strong. We outline how such a component could be organised.http://europepmc.org/articles/PMC4580652?pdf=render |
| spellingShingle | Inaki Tirados Johan Esterhuizen Vanja Kovacic T N Clement Mangwiro Glyn A Vale Ian Hastings Philippe Solano Michael J Lehane Steve J Torr Tsetse Control and Gambian Sleeping Sickness; Implications for Control Strategy. PLoS Neglected Tropical Diseases |
| title | Tsetse Control and Gambian Sleeping Sickness; Implications for Control Strategy. |
| title_full | Tsetse Control and Gambian Sleeping Sickness; Implications for Control Strategy. |
| title_fullStr | Tsetse Control and Gambian Sleeping Sickness; Implications for Control Strategy. |
| title_full_unstemmed | Tsetse Control and Gambian Sleeping Sickness; Implications for Control Strategy. |
| title_short | Tsetse Control and Gambian Sleeping Sickness; Implications for Control Strategy. |
| title_sort | tsetse control and gambian sleeping sickness implications for control strategy |
| url | http://europepmc.org/articles/PMC4580652?pdf=render |
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