Status of insecticide resistance in malaria vectors in Kwale County, Coastal Kenya
Abstract Background The strategy for malaria vector control in the context of reducing malaria morbidity and mortality has been the scale-up of long-lasting insecticidal nets to universal coverage and indoor residual spraying. This has led to significant decline in malaria transmission. However, the...
| Main Authors: | , , , , , |
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| Format: | Article |
| Language: | English |
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BMC
2018-01-01
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| Series: | Malaria Journal |
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| Online Access: | http://link.springer.com/article/10.1186/s12936-017-2156-6 |
| _version_ | 1818839778731229184 |
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| author | Caroline W. Kiuru Florence Awino Oyieke Wolfgang Richard Mukabana Joseph Mwangangi Luna Kamau Damaris Muhia-Matoke |
| author_facet | Caroline W. Kiuru Florence Awino Oyieke Wolfgang Richard Mukabana Joseph Mwangangi Luna Kamau Damaris Muhia-Matoke |
| author_sort | Caroline W. Kiuru |
| collection | DOAJ |
| description | Abstract Background The strategy for malaria vector control in the context of reducing malaria morbidity and mortality has been the scale-up of long-lasting insecticidal nets to universal coverage and indoor residual spraying. This has led to significant decline in malaria transmission. However, these vector control strategies rely on insecticides which are threatened by insecticide resistance. In this study the status of pyrethroid resistance in malaria vectors and it’s implication in malaria transmission at the Kenyan Coast was investigated. Results Using World Health Organization diagnostic bioassay, levels of phenotypic resistance to permethrin and deltamethrin was determined. Anopheles arabiensis showed high resistance to pyrethroids while Anopheles gambiae sensu stricto (s.s.) and Anopheles funestus showed low resistance and susceptibility, respectively. Anopheles gambiae sensu lato (s.l.) mosquitoes were further genotyped for L1014S and L1014F kdr mutation by real time PCR. An allele frequency of 1.33% for L1014S with no L1014F was detected. To evaluate the implication of pyrethroid resistance on malaria transmission, Plasmodium falciparum infection rates in field collected adult mosquitoes was determined using enzyme linked immunosorbent assay and further, the behaviour of the vectors was assessed by comparing indoor and outdoor proportions of mosquitoes collected. Sporozoite infection rate was observed at 4.94 and 2.60% in An. funestus s.l. and An. gambiae s.l., respectively. A higher density of malaria vectors was collected outdoor and this also corresponded with high Plasmodium infection rates outdoor. Conclusions This study showed phenotypic resistance to pyrethroids and low frequency of L1014S kdr mutation in An. gambiae s.l. The occurrence of phenotypic resistance with low levels of kdr frequencies highlights the need to investigate other mechanisms of resistance. Despite being susceptible to pyrethroids An. funestus s.l. could be driving malaria infections in the area. |
| first_indexed | 2024-12-19T03:59:42Z |
| format | Article |
| id | doaj.art-3b73af621a1f4cc786cb742f0ed90e9d |
| institution | Directory Open Access Journal |
| issn | 1475-2875 |
| language | English |
| last_indexed | 2024-12-19T03:59:42Z |
| publishDate | 2018-01-01 |
| publisher | BMC |
| record_format | Article |
| series | Malaria Journal |
| spelling | doaj.art-3b73af621a1f4cc786cb742f0ed90e9d2022-12-21T20:36:42ZengBMCMalaria Journal1475-28752018-01-011711910.1186/s12936-017-2156-6Status of insecticide resistance in malaria vectors in Kwale County, Coastal KenyaCaroline W. Kiuru0Florence Awino Oyieke1Wolfgang Richard Mukabana2Joseph Mwangangi3Luna Kamau4Damaris Muhia-Matoke5School of Biological Sciences, University of NairobiSchool of Biological Sciences, University of NairobiSchool of Biological Sciences, University of NairobiDepartment of Biological Sciences, Pwani UniversityKEMRI-Centre for Biotechnology Research and DevelopmentKEMRI-Centre for Biotechnology Research and DevelopmentAbstract Background The strategy for malaria vector control in the context of reducing malaria morbidity and mortality has been the scale-up of long-lasting insecticidal nets to universal coverage and indoor residual spraying. This has led to significant decline in malaria transmission. However, these vector control strategies rely on insecticides which are threatened by insecticide resistance. In this study the status of pyrethroid resistance in malaria vectors and it’s implication in malaria transmission at the Kenyan Coast was investigated. Results Using World Health Organization diagnostic bioassay, levels of phenotypic resistance to permethrin and deltamethrin was determined. Anopheles arabiensis showed high resistance to pyrethroids while Anopheles gambiae sensu stricto (s.s.) and Anopheles funestus showed low resistance and susceptibility, respectively. Anopheles gambiae sensu lato (s.l.) mosquitoes were further genotyped for L1014S and L1014F kdr mutation by real time PCR. An allele frequency of 1.33% for L1014S with no L1014F was detected. To evaluate the implication of pyrethroid resistance on malaria transmission, Plasmodium falciparum infection rates in field collected adult mosquitoes was determined using enzyme linked immunosorbent assay and further, the behaviour of the vectors was assessed by comparing indoor and outdoor proportions of mosquitoes collected. Sporozoite infection rate was observed at 4.94 and 2.60% in An. funestus s.l. and An. gambiae s.l., respectively. A higher density of malaria vectors was collected outdoor and this also corresponded with high Plasmodium infection rates outdoor. Conclusions This study showed phenotypic resistance to pyrethroids and low frequency of L1014S kdr mutation in An. gambiae s.l. The occurrence of phenotypic resistance with low levels of kdr frequencies highlights the need to investigate other mechanisms of resistance. Despite being susceptible to pyrethroids An. funestus s.l. could be driving malaria infections in the area.http://link.springer.com/article/10.1186/s12936-017-2156-6Malaria vectorsInsecticide resistancekdr |
| spellingShingle | Caroline W. Kiuru Florence Awino Oyieke Wolfgang Richard Mukabana Joseph Mwangangi Luna Kamau Damaris Muhia-Matoke Status of insecticide resistance in malaria vectors in Kwale County, Coastal Kenya Malaria Journal Malaria vectors Insecticide resistance kdr |
| title | Status of insecticide resistance in malaria vectors in Kwale County, Coastal Kenya |
| title_full | Status of insecticide resistance in malaria vectors in Kwale County, Coastal Kenya |
| title_fullStr | Status of insecticide resistance in malaria vectors in Kwale County, Coastal Kenya |
| title_full_unstemmed | Status of insecticide resistance in malaria vectors in Kwale County, Coastal Kenya |
| title_short | Status of insecticide resistance in malaria vectors in Kwale County, Coastal Kenya |
| title_sort | status of insecticide resistance in malaria vectors in kwale county coastal kenya |
| topic | Malaria vectors Insecticide resistance kdr |
| url | http://link.springer.com/article/10.1186/s12936-017-2156-6 |
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