Zaim M

References (5)

Title : Evolution of insecticide resistance and its mechanisms in Anopheles stephensi in the WHO Eastern Mediterranean Region - Enayati_2020_Malar.J_19_258
Author(s) : Enayati A , Hanafi-Bojd AA , Sedaghat MM , Zaim M , Hemingway J
Ref : Malar J , 19 :258 , 2020
Abstract : BACKGROUND: While Iran is on the path to eliminating malaria, the disease with 4.9 million estimated cases and 9300 estimated deaths in 2018 remains a serious health problem in the World Health Organization (WHO) Eastern Mediterranean Region. Anopheles stephensi is the main malaria vector in Iran and its range extends from Iraq to western China. Recently, the vector invaded new territories in Sri Lanka and countries in the Horn of Africa. Insecticide resistance in An. stephensi is a potential issue in controlling the spread of this vector. METHODS: Data were collated from national and international databases, including PubMed, Google Scholar, Scopus, ScienceDirect, SID, and IranMedex using appropriate search terms. RESULTS: Indoor residual spaying (IRS) with DDT was piloted in Iran in 1945 and subsequently used in the malaria eradication programme. Resistance to DDT in An. stephensi was detected in Iran, Iraq, Pakistan, and Saudi Arabia in the late 1960s. Malathion was used for malaria control in Iran in 1967, then propoxur in 1978, followed by pirimiphos-methyl from 1992 to 1994. The pyrethroid insecticide lambda-cyhalothrin was used from 1994 to 2003 followed by deltamethrin IRS and long-lasting insecticidal nets (LLINs). Some of these insecticides with the same sequence were used in other malaria-endemic countries of the region. Pyrethroid resistance was detected in An. stephensi in Afghanistan in 2010, in 2011 in India and in 2012 in Iran. The newly invaded population of An. stephensi in Ethiopia was resistant to insecticides of all four major insecticide classes. Different mechanisms of insecticide resistance, including metabolic and insecticide target site insensitivity, have been developed in An. stephensi. Resistance to DDT was initially glutathione S-transferase based. Target site knockdown resistance was later selected by pyrethroids. Esterases and altered acetylcholinesterase are the underlying cause of organophosphate resistance and cytochrome p450s were involved in pyrethroid metabolic resistance. CONCLUSIONS: Anopheles stephensi is a major malaria vector in Iran and many countries in the region and beyond. The species is leading in terms of development of insecticide resistance as well as developing a variety of resistance mechanisms. Knowledge of the evolution of insecticide resistance and their underlying mechanisms, in particular, are important to Iran, considering the final steps the country is taking towards malaria elimination, but also to other countries in the region for their battle against malaria. This systematic review may also be of value to countries and territories newly invaded by this species, especially in the Horn of Africa, where the malaria situation is already dire.
ESTHER : Enayati_2020_Malar.J_19_258
PubMedSearch : Enayati_2020_Malar.J_19_258
PubMedID: 32680514

Title : Laboratory evaluation of cyromazine against insecticide-susceptible and -resistant mosquito larvae - Darriet_2008_J.Am.Mosq.Control.Assoc_24_123
Author(s) : Darriet F , Zaim M , Corbel V
Ref : J Am Mosq Control Assoc , 24 :123 , 2008
Abstract : In this study, the activity of cyromazine was evaluated following WHO standard procedures against susceptible and resistant mosquito strains of Anopheles gambiae, Culex quinquefasciatus, and Aedes aegypti. The dose for 50% and 90% inhibition of adult emergence (IE50 and IE90) ranged from 0.028 mg/liter to 0.17 mg/liter and from 0.075 mg/liter to 0.42 mg/liter, respectively. The effects of cyromazine were closer to that of chitin synthesis inhibitors rather than that of juvenile hormone analogues, with only 10-20% pupal mortality. The toxicity of cyromazine was not strongly affected by the presence of common resistance mechanism, i.e., Kdr mutation and Ace.1(R) (resistance ratio from 0.5 to 2.3). The absence of cross resistance with common insecticides (pyrethroids, carbamates, organophosphates) makes cyromazine a potential candidate for disease vector control, especially for the management of insecticide resistance.
ESTHER : Darriet_2008_J.Am.Mosq.Control.Assoc_24_123
PubMedSearch : Darriet_2008_J.Am.Mosq.Control.Assoc_24_123
PubMedID: 18437826

Title : Experimental hut evaluation of bednets treated with an organophosphate (chlorpyrifos-methyl) or a pyrethroid (lambdacyhalothrin) alone and in combination against insecticide-resistant Anopheles gambiae and Culex quinquefasciatus mosquitoes - Asidi_2005_Malar.J_4_25
Author(s) : Asidi AN , N'Guessan R , Koffi AA , Curtis CF , Hougard JM , Chandre F , Corbel V , Darriet F , Zaim M , Rowland MW
Ref : Malar J , 4 :25 , 2005
Abstract : BACKGROUND: Pyrethroid resistant mosquitoes are becoming increasingly common in parts of Africa. It is important to identify alternative insecticides which, if necessary, could be used to replace or supplement the pyrethroids for use on treated nets. Certain compounds of an earlier generation of insecticides, the organophosphates may have potential as net treatments.
METHODS: Comparative studies of chlorpyrifos-methyl (CM), an organophosphate with low mammalian toxicity, and lambdacyhalothrin (L), a pyrethroid, were conducted in experimental huts in Cote d'Ivoire, West Africa. Anopheles gambiae and Culex quinquefasciatus mosquitoes from the area are resistant to pyrethroids and organophosphates (kdr and insensitive acetylcholinesterase Ace.1R). Several treatments and application rates on intact or holed nets were evaluated, including single treatments, mixtures, and differential wall/ceiling treatments. RESULTS AND CONCLUSION: All of the treatments were effective in reducing blood feeding from sleepers under the nets and in killing both species of mosquito, despite the presence of the kdr and Ace.1R genes at high frequency. In most cases, the effects of the various treatments did not differ significantly. Five washes of the nets in soap solution did not reduce the impact of the insecticides on A. gambiae mortality, but did lead to an increase in blood feeding. The three combinations performed no differently from the single insecticide treatments, but the low dose mixture performed encouragingly well indicating that such combinations might be used for controlling insecticide resistant mosquitoes. Mortality of mosquitoes that carried both Ace.1R and Ace.1S genes did not differ significantly from mosquitoes that carried only Ace.1S genes on any of the treated nets, indicating that the Ace.1R allele does not confer effective resistance to chlorpyrifos-methyl under the realistic conditions of an experimental hut.
ESTHER : Asidi_2005_Malar.J_4_25
PubMedSearch : Asidi_2005_Malar.J_4_25
PubMedID: 15918909

Title : Dinotefuran: a potential neonicotinoid insecticide against resistant mosquitoes - Corbel_2004_J.Med.Entomol_41_712
Author(s) : Corbel V , Duchon S , Zaim M , Hougard JM
Ref : Journal of Medical Entomology , 41 :712 , 2004
Abstract : Because pyrethroid, organophosphate, and carbamate resistance is more and more developed in mosquitoes of medical importance, there is an urgent need for alternative insecticides for vector control. Dinotefuran, a new neonicotinoid insecticide commercialized by Mitsui Chemicals (Tokyo, Japan), could be a useful candidate in public health because it shows low mammalian toxicity and great insecticidal activity against a broad range of pests. In this study, the intrinsic toxicity of dinotefuran was evaluated by larval bioassay and topical application against different mosquito strains of Anopheles gambiae Giles, Culex quinquefasciatus Say, and Aedes aegypti L. having none, one, or several resistance mechanisms, respectively, to insecticides. The results showed that dinotefuran was less toxic than most of the commonly used insecticides (e.g., deltamethrin, carbosulfan, and temephos) against the susceptible mosquitoes tested (between 6- and 100-fold at the LD50 level). However, the toxicity of dinotefuran was not strongly affected by the presence of common resistance mechanism, i.e., kdr mutation and insensitive acetylcholinesterase (resistance ratio [RR] from 1.3 to 2.3). More interestingly, the carbamate-resistant strain of Cx. quinquefasciatus was significantly more affected by dinotefuran than the susceptible strain (RR = 0.70), probably because the insensitive acetylcholinesterase is less efficient to degrade nicotinic substrates than normal acetylcholinesterase. Despite the relatively low toxicity of dinotefuran against susceptible mosquitoes, the absence of cross-resistance with common insecticides (pyrethroids, carbamates, and organophosphates) makes neonicotinoids potential candidates for disease vector control, especially in area where mosquitoes are resistant to insecticides.
ESTHER : Corbel_2004_J.Med.Entomol_41_712
PubMedSearch : Corbel_2004_J.Med.Entomol_41_712
PubMedID: 15311465

Title : Anopheles culicifacies in Baluchistan, Iran - Zaim_1995_Med.Vet.Entomol_9_181
Author(s) : Zaim M , Manouchehri AV , Motabar M , Emadi AM , Nazari M , Pakdad K , Kayedi MH , Mowlaii G
Ref : Med Vet Entomol , 9 :181 , 1995
Abstract : Anopheles culicifacies (probably species A) is the main vector of malaria in Baluchistan, southeastern Iran. Adult mosquitoes were collected during 1990-92 by five methods of sampling: knock-down pyrethrum space-spray indoors, human and animal bait (18.00-05.00 hours), pit shelters and CDC light traps, yielding 62%, 3%, 6%, 4% and 25% of specimens, respectively. Whereas spray-catches comprised c. 70% gravid and semi-gravid females, light trap catches were mostly (c. 60%) unfed females, while females from pit shelters comprised all abdominal stages more equally (13-36%). An.culicifacies populations peaked in April-May and rose again during August-November. Densities of indoor-resting mosquitoes were consistently greater in an unsprayed village than in villages subjected to residual house-spraying with propoxur, malathion or pirimiphos-methyl. Monthly malaria incidence generally followed fluctuations of An.culicifacies density, usually with a peak in May-June.
ESTHER : Zaim_1995_Med.Vet.Entomol_9_181
PubMedSearch : Zaim_1995_Med.Vet.Entomol_9_181
PubMedID: 7787227