Surveillance for knock downresistant kdr Anopheles gambiae Diptera

Surveillance for knock down-resistant (kdr) Anopheles gambiae (Diptera: Culicidae) in Zimbabwe. Authors: Aramu Makuwaza 1, Nobert Mudare 1, Wietske Mushonga 1, Joel Mouatcho 4, David Nyasvisvo 4, Shadreck Sande 4, Noe Rakotondrajaona 4, Joseph Mberikunashe 3, Susan L. Mutambu 2, Adeline Chan 6, Hieronymo T. Masendu 4, Sungano Mharakurwa. 1 1 Africa University, Mutare, Zimbabwe 2 National Institute of Health Research (NIHR), Harare, Zimbabwe, 3 National Malaria Control Programme, Harare, Zimbabwe, 4. President’s Malaria Initiative Africa Indoor Residual Spraying Project, Zimbabwe, 5 President’s Malaria Initiative, Zimbabwe Assistance Programme in Malaria, Zimbabwe, 6 Centers for Disease Control and prevention Entomology Branch, Atlanta, USA. BACKGROUND v Malaria transmission in Zimbabwe is generally unstable and affects at RESULTS & DISCUSSION Composition of An. gambiae complex sibling species were high in both adults collected mosquitos as least 50% of the country’s population which resides in rural areas well as adults raised from larval collection. Anopheles quadriannulatus on average were (80. 7%), An. (MOHCW, 2012). arabiensis (11. 1%), An. gambiae ss (3. 3%) and An. merus (5. 1%). There is scarcity of expertise for v Control of malaria is conducted by the MOHCC through the NMCP. The NMCP coordinate IRS, Insecticide Treated materials (ITMs), larviciding and insecticides resistance monitoring. v Insecticide resistance monitoring is done on yearly basis in malaria rigorous morphological identification of mosquito to complex level. Kdr mutations were detected in An. arabiensis and An. quadriannulatus in Manicaland province. Adults Anopheles mosquito raised from larvae and exposed to insecticide resistance papers. . prone parts of the country to assessment insecticide susceptibility status. Regular surveillance allows detection of resistance much earlier and replaces it with other effective insecticides. v Insecticide resistance is an immediate threat and might already be contributing to the increase in malaria cases making it a serious and 216 Qs 216 Du 216 b 34 Qs 34 Cu 34 b M 210 Qs Figure 4: Distribution of kdr mutation forms on An. gambiae complex mosquitoes in Zimbabwe. 210 Qu 210 b Qs- Cu- b- 3 D 7 current public health problem. GENERAL OBJECTIVE To collect base line information on distribution of knock down resistance (kdr), mutations on Anopheles gambiae complex Figure 1 : Adults An. mosquito raised from larvae submitted sibling species by molecular means. . by site after exposure to insecticide resistance papers. . METHODS v An entomological surveillance was conducted on larvae and adults in 8 provinces of Zimbabwe, ( Manicaland, Midlands, Masvingo, Anopheles mosquitoes submitted by sentinel site for species identification. by PCR Mashonaland East, Mashonaland West, Mashonaland Central, Figure 5 : Distribution of kdr mutation forms within sibling species per sentinel site Matabeleland North and Matabeleland South). CONCLUSIONS & RECOMMENDATION v 301 An. gambiae adults raised from larvae and 424 collected as Emerging Kdr mutation forms, east and west detected in all An. gambiae sibling species. High proportion of An. adult mosquito ( CDC in/out, PSC, HLC proxy). The 724 An. quadriannulators (80. 7 %) as compared to other sibling species An. arabiensis (11. 1%), An. gambiae ss (3. 3%) with An. merus gambiae sibling species were subjected to the kdr assay (5. 1%) therefor need to adapt below mentioned framework. This study recommends that assays for resistance to be based on v DNA extraction was carried out by using the Bender buffer method F 1 or F 2 generation after identifying the sibling species first by PCR as it is cost effective. as described by Collins et al, (1987). v Mosquito specimens belonging to the An. funestus group were removed after a multiplex PCR assay protocol developed by Koekemoer and others (Koekemoer, et al. , 2002). Mosquito Figure 2: Species from sentinel site submitted for identification by PCR. specimens belonging to the An. gambiae group were analysed by a An. gambiae L 1014 F (kdr west) mutation and L 1014 S (kdr east) mutation were detected in multiplex PCR assay protocol developed by Wilkins and others Chakohwa and Burma Valley. (Wilkins et al. , 2006). v The kdr west African form results from leucine to phenylalanine substitution (TTA/TTT) (Martinez-Torres et al. 1998). The kdr east African form results from a leucine to serine substitution (TTA/TCA) (Ranson et al. 2000). Figur 6 : Proposed insecticide resistance monitoring framework REFERENCES 1. Kwang S Choi, Riann Christian, Luisa Nardini, Oliver R Wood, Eunice Agubuzo, Mbanga Muleba, Shungu Munyati, Aramu Makuwaza, Lizette L Koekemoer, Basil D Brooke, Richard H Hunt and Maureen Coetzee, (2014). Insecticide resistance and role in malaria transmission of Anopheles funestus populations from Zambia and Zimbabwe. Parasites & Vectors, 7: 464 2. Shadreck Sande, Moses Zimba, Peter Chinwada Hieronymo Takudzwa Masendu, Sungai Mazando and Aramu Makuwaza (2015). The emergence of insecticide resistance in the major malaria vector Anopheles funestus (Diptera: Culicidae) from sentinel sites in Mutare and Mutasa Districts, Zimbabwe. Malaria Journal, 14: 466 Figure 3: Proportion of An. gambiae complex mosquitoes collected as larvae compared to adults from living structures. . doi: 10. 1186/s 12936 -015 -0993.