Infection of malaria (<it>Anopheles gambiae s.s.</it>) and filariasis (<it>Culex quinquefasciatus</it>) vectors with the entomopathogenic fungus <it>Metarhizium anisopliae</it>
<p>Abstract</p> <p>Background</p> <p>Current intra-domiciliary vector control depends on the application of residual insecticides and/or repellents. Although biological control agents have been developed against aquatic mosquito stages, none are available for adults. Fo...
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| Format: | Article |
| Language: | English |
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BMC
2003-09-01
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| Series: | Malaria Journal |
| Online Access: | http://www.malariajournal.com/content/2/1/29 |
| _version_ | 1818496524944932864 |
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| author | Smallegange Renate C Njiru Basilio N Scholte Ernst-Jan Takken Willem Knols Bart GJ |
| author_facet | Smallegange Renate C Njiru Basilio N Scholte Ernst-Jan Takken Willem Knols Bart GJ |
| author_sort | Smallegange Renate C |
| collection | DOAJ |
| description | <p>Abstract</p> <p>Background</p> <p>Current intra-domiciliary vector control depends on the application of residual insecticides and/or repellents. Although biological control agents have been developed against aquatic mosquito stages, none are available for adults. Following successful use of an entomopathogenic fungus against tsetse flies (Diptera: Glossinidae) we investigated the potency of this fungus as a biological control agent for adult malaria and filariasis vector mosquitoes.</p> <p>Methods</p> <p>In the laboratory, both sexes of <it>Anopheles gambiae sensu stricto </it>and <it>Culex quinquefasciatus </it>were passively contaminated with dry conidia of <it>Metarhizium anisopliae</it>. Pathogenicity of this fungus for <it>An. gambiae </it>was further tested for varying exposure times and different doses of oil-formulated conidia.</p> <p>Results</p> <p>Comparison of Gompertz survival curves and LT<sub>50 </sub>values for treated and untreated specimens showed that, for both species, infected mosquitoes died significantly earlier (p < 0.0001) than uninfected control groups. No differences in LT<sub>50 </sub>values were found for different exposure times (24, 48 hrs or continuous exposure) of <it>An. gambiae </it>to dry conidia. Exposure to oil-formulated conidia (doses ranging from 1.6 × 10<sup>7 </sup>to 1.6 × 10<sup>10 </sup>conidia/m<sup>2</sup>) gave LT<sub>50 </sub>values of 9.69 ± 1.24 (lowest dose) to 5.89 ± 0.35 days (highest dose), with infection percentages ranging from 4.4–83.7%.</p> <p>Conclusion</p> <p>Our study marks the first to use an entomopathogenic fungus against adult Afrotropical disease vectors. Given its high pathogenicity for both adult <it>Anopheles </it>and <it>Culex </it>mosquitoes we recommend development of novel targeted indoor application methods for the control of endophagic host-seeking females.</p> |
| first_indexed | 2024-12-10T18:34:00Z |
| format | Article |
| id | doaj.art-ecab8483fcd44d608317e36d020513f0 |
| institution | Directory Open Access Journal |
| issn | 1475-2875 |
| language | English |
| last_indexed | 2024-12-10T18:34:00Z |
| publishDate | 2003-09-01 |
| publisher | BMC |
| record_format | Article |
| series | Malaria Journal |
| spelling | doaj.art-ecab8483fcd44d608317e36d020513f02022-12-22T01:37:52ZengBMCMalaria Journal1475-28752003-09-01212910.1186/1475-2875-2-29Infection of malaria (<it>Anopheles gambiae s.s.</it>) and filariasis (<it>Culex quinquefasciatus</it>) vectors with the entomopathogenic fungus <it>Metarhizium anisopliae</it>Smallegange Renate CNjiru Basilio NScholte Ernst-JanTakken WillemKnols Bart GJ<p>Abstract</p> <p>Background</p> <p>Current intra-domiciliary vector control depends on the application of residual insecticides and/or repellents. Although biological control agents have been developed against aquatic mosquito stages, none are available for adults. Following successful use of an entomopathogenic fungus against tsetse flies (Diptera: Glossinidae) we investigated the potency of this fungus as a biological control agent for adult malaria and filariasis vector mosquitoes.</p> <p>Methods</p> <p>In the laboratory, both sexes of <it>Anopheles gambiae sensu stricto </it>and <it>Culex quinquefasciatus </it>were passively contaminated with dry conidia of <it>Metarhizium anisopliae</it>. Pathogenicity of this fungus for <it>An. gambiae </it>was further tested for varying exposure times and different doses of oil-formulated conidia.</p> <p>Results</p> <p>Comparison of Gompertz survival curves and LT<sub>50 </sub>values for treated and untreated specimens showed that, for both species, infected mosquitoes died significantly earlier (p < 0.0001) than uninfected control groups. No differences in LT<sub>50 </sub>values were found for different exposure times (24, 48 hrs or continuous exposure) of <it>An. gambiae </it>to dry conidia. Exposure to oil-formulated conidia (doses ranging from 1.6 × 10<sup>7 </sup>to 1.6 × 10<sup>10 </sup>conidia/m<sup>2</sup>) gave LT<sub>50 </sub>values of 9.69 ± 1.24 (lowest dose) to 5.89 ± 0.35 days (highest dose), with infection percentages ranging from 4.4–83.7%.</p> <p>Conclusion</p> <p>Our study marks the first to use an entomopathogenic fungus against adult Afrotropical disease vectors. Given its high pathogenicity for both adult <it>Anopheles </it>and <it>Culex </it>mosquitoes we recommend development of novel targeted indoor application methods for the control of endophagic host-seeking females.</p>http://www.malariajournal.com/content/2/1/29 |
| spellingShingle | Smallegange Renate C Njiru Basilio N Scholte Ernst-Jan Takken Willem Knols Bart GJ Infection of malaria (<it>Anopheles gambiae s.s.</it>) and filariasis (<it>Culex quinquefasciatus</it>) vectors with the entomopathogenic fungus <it>Metarhizium anisopliae</it> Malaria Journal |
| title | Infection of malaria (<it>Anopheles gambiae s.s.</it>) and filariasis (<it>Culex quinquefasciatus</it>) vectors with the entomopathogenic fungus <it>Metarhizium anisopliae</it> |
| title_full | Infection of malaria (<it>Anopheles gambiae s.s.</it>) and filariasis (<it>Culex quinquefasciatus</it>) vectors with the entomopathogenic fungus <it>Metarhizium anisopliae</it> |
| title_fullStr | Infection of malaria (<it>Anopheles gambiae s.s.</it>) and filariasis (<it>Culex quinquefasciatus</it>) vectors with the entomopathogenic fungus <it>Metarhizium anisopliae</it> |
| title_full_unstemmed | Infection of malaria (<it>Anopheles gambiae s.s.</it>) and filariasis (<it>Culex quinquefasciatus</it>) vectors with the entomopathogenic fungus <it>Metarhizium anisopliae</it> |
| title_short | Infection of malaria (<it>Anopheles gambiae s.s.</it>) and filariasis (<it>Culex quinquefasciatus</it>) vectors with the entomopathogenic fungus <it>Metarhizium anisopliae</it> |
| title_sort | infection of malaria it anopheles gambiae s s it and filariasis it culex quinquefasciatus it vectors with the entomopathogenic fungus it metarhizium anisopliae it |
| url | http://www.malariajournal.com/content/2/1/29 |
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