Ovary Dissection Is a Sensitive Measure of Sterility in <i>Anopheles gambiae</i> Exposed to the Insect Growth Regulator Pyriproxyfen
Pyriproxyfen (PPF) is an insect growth regulator used in the co-treatment of long-lasting insecticidal nets for its ability to sterilize female mosquitoes. To evaluate the efficacy of PPF-treated nets on mosquito reproductivity, most studies observe oviposition (egg-laying) rates in the laboratory....
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| Format: | Article |
| Language: | English |
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MDPI AG
2023-06-01
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| Series: | Insects |
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| Online Access: | https://www.mdpi.com/2075-4450/14/6/552 |
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| author | Alina Soto Mark Rowland Louisa A. Messenger Mathew Kirby Franklin W. Mosha Alphaxard Manjurano Natacha Protopopoff |
| author_facet | Alina Soto Mark Rowland Louisa A. Messenger Mathew Kirby Franklin W. Mosha Alphaxard Manjurano Natacha Protopopoff |
| author_sort | Alina Soto |
| collection | DOAJ |
| description | Pyriproxyfen (PPF) is an insect growth regulator used in the co-treatment of long-lasting insecticidal nets for its ability to sterilize female mosquitoes. To evaluate the efficacy of PPF-treated nets on mosquito reproductivity, most studies observe oviposition (egg-laying) rates in the laboratory. This technique has several technical disadvantages. Our study assessed if ovarial dissection could serve as an effective proxy for evaluating sterility in <i>Anopheles gambiae</i> mosquitoes. Blood-fed females were exposed to untreated or PPF-treated nets in cylinder assays and followed over several days to observe oviposition rates or egg development by dissection. For identifying PPF-exposed mosquitoes, both techniques demonstrated high sensitivity (oviposition: 99.1%; dissection: 100.0%), but for identifying non-exposed mosquitoes, specificity was significantly higher in the dissection group (52.5% vs. 18.9%). To assess whether dissection could be applied to nets treated with a pyrethroid or co-treated with a pyrethroid and PPF in tunnel tests, a blinded investigator performed dissections to predict the PPF exposure status across different treatment groups. The exposure status of dissected females was predicted with >90% accuracy. We report that dissection is a sensitive technique to assess sterility in female Anopheles gambiae mosquitoes and can be used as a predictor of PPF exposure. |
| first_indexed | 2024-03-11T02:19:25Z |
| format | Article |
| id | doaj.art-6f6f961a0efb413882c9f22a4dad3e33 |
| institution | Directory Open Access Journal |
| issn | 2075-4450 |
| language | English |
| last_indexed | 2024-03-11T02:19:25Z |
| publishDate | 2023-06-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Insects |
| spelling | doaj.art-6f6f961a0efb413882c9f22a4dad3e332023-11-18T10:56:23ZengMDPI AGInsects2075-44502023-06-0114655210.3390/insects14060552Ovary Dissection Is a Sensitive Measure of Sterility in <i>Anopheles gambiae</i> Exposed to the Insect Growth Regulator PyriproxyfenAlina Soto0Mark Rowland1Louisa A. Messenger2Mathew Kirby3Franklin W. Mosha4Alphaxard Manjurano5Natacha Protopopoff6Department of Disease Control, London School of Hygiene & Tropical Medicine, London WC1E 7HT, UKDepartment of Disease Control, London School of Hygiene & Tropical Medicine, London WC1E 7HT, UKDepartment of Disease Control, London School of Hygiene & Tropical Medicine, London WC1E 7HT, UKPMI VectorLink Project, Abt Associates, 6130 Executive Blvd., Rockville, MD 20852, USAPan African Malaria Vector Research Consortium, Kilimanjaro Christian Medical University College, Moshi P.O. Box 2240, TanzaniaNational Institute for Medical Research Tanzania, Mwanza P.O. Box 9653, TanzaniaDepartment of Disease Control, London School of Hygiene & Tropical Medicine, London WC1E 7HT, UKPyriproxyfen (PPF) is an insect growth regulator used in the co-treatment of long-lasting insecticidal nets for its ability to sterilize female mosquitoes. To evaluate the efficacy of PPF-treated nets on mosquito reproductivity, most studies observe oviposition (egg-laying) rates in the laboratory. This technique has several technical disadvantages. Our study assessed if ovarial dissection could serve as an effective proxy for evaluating sterility in <i>Anopheles gambiae</i> mosquitoes. Blood-fed females were exposed to untreated or PPF-treated nets in cylinder assays and followed over several days to observe oviposition rates or egg development by dissection. For identifying PPF-exposed mosquitoes, both techniques demonstrated high sensitivity (oviposition: 99.1%; dissection: 100.0%), but for identifying non-exposed mosquitoes, specificity was significantly higher in the dissection group (52.5% vs. 18.9%). To assess whether dissection could be applied to nets treated with a pyrethroid or co-treated with a pyrethroid and PPF in tunnel tests, a blinded investigator performed dissections to predict the PPF exposure status across different treatment groups. The exposure status of dissected females was predicted with >90% accuracy. We report that dissection is a sensitive technique to assess sterility in female Anopheles gambiae mosquitoes and can be used as a predictor of PPF exposure.https://www.mdpi.com/2075-4450/14/6/552pyriproxyfeninsect growth regulator<i>Anopheles gambiae</i>malaria controllong-lasting insecticidal netspyrethroid resistance |
| spellingShingle | Alina Soto Mark Rowland Louisa A. Messenger Mathew Kirby Franklin W. Mosha Alphaxard Manjurano Natacha Protopopoff Ovary Dissection Is a Sensitive Measure of Sterility in <i>Anopheles gambiae</i> Exposed to the Insect Growth Regulator Pyriproxyfen Insects pyriproxyfen insect growth regulator <i>Anopheles gambiae</i> malaria control long-lasting insecticidal nets pyrethroid resistance |
| title | Ovary Dissection Is a Sensitive Measure of Sterility in <i>Anopheles gambiae</i> Exposed to the Insect Growth Regulator Pyriproxyfen |
| title_full | Ovary Dissection Is a Sensitive Measure of Sterility in <i>Anopheles gambiae</i> Exposed to the Insect Growth Regulator Pyriproxyfen |
| title_fullStr | Ovary Dissection Is a Sensitive Measure of Sterility in <i>Anopheles gambiae</i> Exposed to the Insect Growth Regulator Pyriproxyfen |
| title_full_unstemmed | Ovary Dissection Is a Sensitive Measure of Sterility in <i>Anopheles gambiae</i> Exposed to the Insect Growth Regulator Pyriproxyfen |
| title_short | Ovary Dissection Is a Sensitive Measure of Sterility in <i>Anopheles gambiae</i> Exposed to the Insect Growth Regulator Pyriproxyfen |
| title_sort | ovary dissection is a sensitive measure of sterility in i anopheles gambiae i exposed to the insect growth regulator pyriproxyfen |
| topic | pyriproxyfen insect growth regulator <i>Anopheles gambiae</i> malaria control long-lasting insecticidal nets pyrethroid resistance |
| url | https://www.mdpi.com/2075-4450/14/6/552 |
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