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Kdr genotyping and the first report of V410L and V1016I kdr mutations in voltage-gated sodium channel gene in Aedes aegypti (Diptera: Culicidae) from Iran

Abstract

Background

Aedes aegypti is the main vector of arboviral diseases worldwide. The species invaded and became established in southern Iran in 2020. Insecticide-based interventions are primarily used for its control. With insecticide resistance widespread, knowledge of resistance mechanisms is vital for informed deployment of insecticidal interventions, but information from Iranian Ae. aegypti is lacking.

Methods

Fifty-six Ae. aegypti specimens were collected from the port city of Bandar Lengeh in Hormozgan Province in the South of Iran in 2020 and screened for kdr mutations. The most common kdr mutations in Latin America and Asia (V410L, S989P, V1016G/I and F1534C), especially when present in combinations, are highly predictive of DDT and pyrethroid resistance were detected. Phylogenetic analyses based on the diversity of S989P and V1016G/I mutations were undertaken to assess the phylogeography of these kdr mutations.

Results

Genotyping all four kdr positions of V410L, S989P, V1016G/I and F1534C revealed that only 16 out of the 56 (28.57%) specimens were homozygous wild type for all kdr mutation sites. Six haplotypes including VSVF (0.537), VSVC (0.107), LSVF (0.016), LSIF (0.071), VPGC (0.257) and LPGC (0.011) were detected in this study. For the first time, 11 specimens harbouring the V410L mutation, and 8 samples with V1016I mutation were found. V410L and V1016I were coincided in 8 specimens. Also, six specimens contained 1016G/I double mutation which was not reported before.

Conclusions

The relatively high frequency of these kdr mutations in Iranian Ae. aegypti indicates a population exhibiting substantial resistance to pyrethroid insecticides, which are used widely in control operations and household formulations. The detection of the 410L/1016I kdr mutant haplotype in Iranian Ae. aegypti suggests possible convergence of invasive populations from West Africa or Latin America. However, as Iran has very limited maritime/air connections with those African countries, a Latin American origin for the invasive Ae. aegypti in Iran is more plausible.

Graphical abstract

Background

Almost half of the world population lives in dengue-endemic countries [1]. The global distribution of dengue, chikungunya and Zika is expanding, causing severe disease outbreaks in many urban populations [2]. This increase in disease burden is closely tied to changes in the distribution of the main vector, Aedes aegypti, which is in turn largely driven by international trade, travel and climate change [3]. Aedes aegypti has invaded the Middle East in recent decades and most of Iran’s neighbouring countries harbour this vector species [4, 5]. Moreover, dengue, the most-important Aedes-borne arbovirus, is endemic in Pakistan [6, 7], Afghanistan [8], Saudi Arabia [9, 10], Yemen [11] and to a lesser extent Oman [12]. To date, only few imported cases of dengue have been reported from Iran [13].

Insecticide-based mosquito control is an important strategy for outbreak response and epidemic control. However, insecticide resistance in Ae. aegypti is a major threat to effective disease control and may even be a contributing factor to the re-emergence and spread of this species [14]. More than 50 countries have reported resistance to at least one class of insecticide in Ae. aegypti [15]. Mutations in the voltage-gated sodium channel (Vgsc) typically appear to be the main mechanism of pyrethroid insecticide resistance in Ae. aegypti [15, 16]. Multiple Vgsc mutations are known in Ae. aegypti, of which V410L, S989P, V1016G, V1016I and F1534C appear the most widespread and important for resistance-prediction, especially when combined as double or triple mutant haplotypes [15,16,17].

Genotyping Vgsc gene of different populations of Ae. aegypti in Saudi Arabia revealed S989P, V1016G and F1534C mutations causing permethrin and deltamethrin resistance [18, 19]. In Pakistan, India and Sri Lanka, 1534C kdr mutation was detected with different frequencies and involved more in DDT and class I than class II pyrethroid insecticide resistance [20,21,22,23,24]. In Thailand, V1016G (homozygous) and F1534C were involved in deltamethrin and permethrin resistance respectively [25,26,27]. In studies on Ae. aegypti from Malaysia and Indonesia, S989P, F1534C and V1016G were detected causing DDT and pyrethroid insecticide resistance [28,29,30,31,32]. V410L was reported for the first time by Haddi et al. in Brazil [33] followed by reports from other countries in the Americas and Africa [34, 35]. Kdr alleles and haplotypes differ continentally: 989P and 1016G are common in Asia [28, 32, 36,37,38,39,40]; V410L and 1016I are widespread in the Americas, and 1534C is reported worldwide [16, 17, 41,42,43,44,45,46,47,48]. The V410L and V1016I mutations have recently been detected in African populations of Ae. aegypti from Angola, Senegal, Ghana, Cape Verde and Burkina Faso [17, 35, 41, 49,50,51,52] and V1016I in Madeira Island (Portugal) in Europe (near Africa) [53]. The kdr mutations V410L and V1016I in African populations appear to have originated in the Americas [50].

Different kdr mutations exert both qualitatively and quantitatively different effects on the level of insecticide resistance in Ae. aegypti. The V1016G mutant alone can cause resistance to pyrethroids, whereas V1016I alone has no effect and also because of fitness cost never occurs in isolation [48, 54]. However, the V1016I + F1534C double-mutant haplotype is more resistant to deltamethrin and permethrin than F1534C alone [42, 48]. Generally, F1534C confers higher resistance to class I pyrethroid insecticides (e.g. permethrin) than to class II pyrethroids (e.g. deltamethrin; alphacypermethrin) but the latter is elevated when in combination with mutants at the 1016 codon [53, 55]. In Latin America, it has been proposed that F1534C first emerged in response to DDT and/or type I pyrethroid use, providing a platform for the subsequent selection of the V1016I and V410L mutants providing a greater level and broader spectrum of pyrethroid resistance [54]. Asian kdr variants are also more effective in combinations with the 989P + 1016G haplotype conferring operational resistance to pyrethroid sprays especially when homozygous [56], while addition of the 1534C allele reduces Vgsc sensitivity still further [16, 57].

Although Ae. aegypti was historically reported from Iran, in the cities of Khorramshahr in 1920 and Bushehr in the early 1950s [58, 59], there has been no recent report of Ae. aegypti in the country. Nevertheless, Iran’s ecology and climate are able to support the species [4, 60]. As the species is present in almost all neighbouring countries, reinvasion was expected. Aedes aegypti was again detected in Hormozgan Province, southern Iran, in 2020, where the species is now established [13, 61]. Iranian national guidelines for Ae. aegypti control recommend environmental management and source reduction followed by insecticide-based interventions [13]. At this early stage of reinvasion, it is challenging to obtain the high numbers of specimens required to perform standard adult susceptibility bioassays, but resistance information is urgently required to implement effective control measures. Given the high predictive value of kdr mutations, molecular genotyping studies provide a feasible proxy for likely pyrethroid insecticide resistance patterns that might adversely impact control.

Methods

Study area

Lengeh is a port city in Hormozgan Province between 26°33′29″N and 54°52′50″ E. The province is located in southern Iran between 53°41'–59°15'E and 25°24'–28°57'N. It is bounded by Fars and Kerman Provinces in the north, Bushehr Province in the west, the Persian Gulf and the Sea of Oman in the south and Sistan and Baluchestan Provinces in the east (Fig. 1). Hormozgan’s climate is warm and humid and the maximum temperature reaches up to 49 °C in summer, while in the winter the minimum temperature can drop to about 5 °C.

Fig. 1
figure 1

Map of Iran and the study area in the south of the country in Bandar Lengeh

Sample collection

A total of 307 egg, 40 larval, 2 pupal and 5 adult Ae. aegypti specimens were collected from January to December 2020 from different areas of Lengeh port by ovitraps, larval (dippers and droppers) and adult (aspirator) collection based on the national guidelines for prevention and control of Ae. aegypti and Aedes albopictus in Iran [13]. The sampling places were the port as well as inside the city from air conditioner water collection buckets, used tyre piles and broken boats. The coordinates of the exact sampling sites are given in Appendix 1. Immature stages were reared to adults in an insectary with standard conditions of 28 ± 2 °C and 75 ± 5% relative humidity and fed with TetraMin® flakes. Altogether 56 adult Ae. aegypti specimens were available for molecular analysis.

DNA isolation

DNA from individual mosquitoes was extracted using the Livak buffer extraction method [62] with some modifications [63]. In brief, individual mosquitoes were homogenized in 100 μl pre-heated (65 °C) Livak buffer in 1.5-ml Eppendorf tubes using a plastic pestle. Homogenates were incubated at 65 °C for 30 min. Potassium acetate was added to each tube to a final concentration of 1 M before incubating the mixture on ice for 30 min. The tubes were centrifuged at 12,000g for 15 min at 4 °C. Supernatants were transferred to clean tubes and mixed with 200 μl ice-cold ethanol, followed by centrifugation at 12,000g for 15 min at 4 °C. Pellets were rinsed in 100 μl 70% ice-cold ethanol, spun at 12,000g for 5 min at 4 °C and re-suspended in 50 μl pre-heated Tris–EDTA (TE) buffer or nuclease-free water.

Primers

Three different sets of primers were designed/used to amplify three separate fragments of the IS6, IIS6 and IIIS6 of the Vgsc gene of Ae. aegypti in PCR reactions (Table 1). V410fw, L410fm and 410rev primers were used in an allele-specific PCR followed by melting curve analysis to genotype the V410L position [55]. In PCR2, using primers kdrseq-F and kdrseq-R, a flanking region of 633 bp in domain II of the Vgsc gene was amplified followed by sequencing in both directions to detect the S989P and V1016G/I mutations. Two external primers, kdrext-F and kdrext-R, as well as two specific primers, wildint-F and mutant-R, were used in an allele-specific PCR (PCR3) to genotype the F1534C position of the Vgsc gene of Ae. aegypti according to Harris et al. with some modifications [64]. Some of the PCR1 and PCR3 products were also sequenced using the external primer pairs (Table 1) to ensure that the genotyping techniques worked well. A schematic diagram showing the stretch of the IS6, IIS5-6 and IIIS6 of the Vgsc gene where the primers bind is given in Fig. 2.

Table 1 Primers used in different PCR of the Vgsc gene of Aedes aegypti from Iran
Fig. 2
figure 2

Schematic diagram of the stretch of the Vgsc gene of Aedes aegypti depicting where the primers sit in three different PCR reactions for genotyping V410L, S989P, V1016G/I and F1534C kdr mutations. A: PCR1, B: PCR2 and C: PCR3

PCR protocols

In the PCR1, the reaction mixture (25 μl) contained 10 µl RealQ Plus 2 × Master Mix Green (Ampliqon, Denmark), 0.4 µM of each primer and 100 ng of the extracted DNA. The reactions were run on a StepOnePlus™ Real-Time PCR System (Applied Biosystems, USA) by the following protocol: an initial denaturation and hot-start enzyme activation at 95 °C for 10 min, then 37 cycles at 94 °C for 30 s, 60 °C for 30 s and 72 °C for 30 s, and a final extension step at 72 °C for 7 min. Two unequal-sized PCR products produced by the wild-type and mutant alleles were differentiated by melt curve analysis at 65 °C to 95 °C in 0.1 °C increment steps on the device [55]. PCR2 was performed in a reaction mixture (25 μl) that contained 1 × buffer, 1.5 mM of MgCl2, 200 μM of each dNTP, 0.5 μM of each kdrext-F and kdrext-R primer and 0.625 unit of High-Fidelity DNA Polymerase (Ampliqon, Denmark). The PCR protocol was: an initial denaturation at 95 °C for 2 min, followed by 35 cycles at 95 °C for 30 s, 60 °C for 30 s and 72 °C for 45 s, and a final extension step at 72 °C for 7 min. The products of the PCR 2 were run on a 2% agarose gel and the bands were cut and the DNA extracted using a PCR purification kit (Takapozist, Iran); they were sequenced in both directions (Macrogen Inc., South Korea) using BigDye (Applied Biosystem Chemistry). PCR3 protocol was similar to PCR2 except that all four primers were used in each reaction and the products were run on 2% agarose gel to observe different banding patterns of 137 bp (F1534C: mutant), 265 bp (F1534: wild type) and 358 bp (control).

Data analysis

Melting curve analysis of PCR1 was performed using StepOnePlus software (Applied Biosystems, USA) for V410L genotyping. All the sequencing data of the PCR2 products were analysed using CLC Genomics Workbench software v20.0.04 (QIAGEN, Germany) and the mutations at the S989P and V1016G/I positions were identified by aligning them with the reference sequences (gene ID: 5567355). Three different nucleotide sequences containing S909P, V1016G, V1016I and 1016G/I were used as queries to search for similar sequences in GenBank using nucleotide blast (https://blast.ncbi.nlm.nih.gov/Blast.cgi). All the existing sequences containing mutations in the S989P and V1016G/I positions in the database were downloaded and used for the phylogenetic analysis using CLC Genomics Workbench. For PCR3, banding pattern differences on 2% agarose gel were used to analyse the allele-specific PCR products to genotype F1534C kdr mutation. The phylogenetic tree was constructed using the UPGMA method with 1000 bootstrap replicates by CLC Genomics Workbench software v20.0.04. Chi-square statistical test was used to assess the correlation between different genotypes in a SPSS v22 software at the significance level of 5%.

Results

Molecular analyses were successfully performed on all 56 specimens of Ae. aegypti collected from Lengeh Port City. Allele-specific PCR followed by melting curve analysis for genotyping the V410L position of the Vgsc gene of Ae. aegypti from Iran revealed peaks with different melting points (Fig. 3). V410L heterozygotes (in red) produced two peaks at 82.5 °C (410L) and 85.5 °C (V410). V410 susceptible homozygote produced a single peak at 85.5 °C (in black). Some of the PCR products of the V410L position were sequenced to assure the sensitivity of the melting curve analyses (Fig. 4). PCR followed by sequencing (PCR2) and allele-specific PCR (PCR3) revealed several kdr mutations in the Vgsc gene of the mosquitoes including S989P, V1016G, V1016I, 1016G/I and F1534C. Chromatograms of the mutations S989P, V1016G, V1016I and 1016G/I are shown in Figs. 5, 6, 7. Banding patterns showing the detection of the F1534C mutation are depicted in Fig. 8.

Fig. 3
figure 3

Allele-specific melting-curve real-time PCR of the IS6 of the Vgsc gene of Aedes aegypti from Iran. V410L heterozygotes (in red) produced two peaks at about 82.5 °C (410L) and 85.5 °C (V410). V410-susceptible homozygote produced a single peak at about 85.5 °C (in black)

Fig. 4
figure 4

Sequence of a stretch of Vgsc gene of Aedes aegypti from Iran showing the V410L mutation (GG: homozygote wild, GA: heterozygote). GTA and ATA genetic codes for valine and leucine respectively

Fig. 5
figure 5

Sequence of a stretch of Vgsc gene of Aedes aegypti from Iran showing the S989P mutation (CC: homozygote mutant, CT: heterozygote and TT: wild type). TCC and CCC genetic codes for serine and proline respectively

Fig. 6
figure 6

Sequence of a stretch of Vgsc gene of Aedes aegypti from Iran showing the V1016G/I mutations (GG: homozygote mutant, GT: heterozygote and TT: wild type; GA: heterozygote 1016I). GTA, GGA and ATA genetic codes for valine, glycine and isoleucine respectively

Fig. 7
figure 7

Sequence of a stretch of Vgsc gene of Aedes aegypti from Iran showing the F1534C mutation (GG: homozygote mutant, GT: heterozygote and TT: wild type). TTC and TGC genetic codes for phenylalanine and cysteine respectively

Fig. 8
figure 8

Agarose gel electrophoresis of allele specific PCR3 product showing different banding patterns for the F1534C mutation in Vgsc gene of Aedes aegypti from Iran. Lane 1: homozygote mutant; lanes 2 and 3: heterozygote; lane 4: homozygote wild; lane 5: negative control and lane 6: DNA ladder

Based on the kdr genotyping results of 56 Iranian Ae. aegypti, 16 (28.57%) specimens were homozygote wild type at all positions. The frequencies of the genotypes and haplotypes are summarized in the Appendix 2 and Tables 2 and 3. At the V410L position, 11 specimens (19.6%) were heterozygote and no individual homozygous for 410L was found. The frequency of S989, S989P and 989P alleles was 50% (28 specimens), 46.4% (26) and 3.6% (2) respectively. At the V1016G/I position, 26 (46%), 20 (36%), 2 (3.6%), 2 (3.6) and 6 (11%) specimens were wild type, heterozygous for 1016G, homozygous for 1016G, heterozygous for 1016I and heterozygous for 1016G/I respectively. At the F1534C position, 19 (34%), 32 (57%) and 5 (9%) specimens were homozygote wild type, heterozygote and homozygote mutant respectively. All V410L specimens were also heterozygous for V1016I or 1016G/I mutations with statistically significant association (χ2 = 0.001). Six haplotypes with different frequencies including VSVF (0.537), VSVC (0.107), LSVF (0.016), LSIF (0.071), VPGC (0.257) and LPGC (0.011) were detected in this study. About half of the haplotypes contain at least one kdr mutation. A haplotype containing 1016I mutation has never been seen with S989P. The results of genotyping kdr mutations at different domains of the Vgsc gene of Ae. aegypti from Iran indicate relatively strong DDT and pyrethroid insecticide resistance.

Table 2 List and frequency of haplotypes and genotypes of Aedes aegypti from Iran
Table 3 List and frequency of haplotypes and the number of kdr alleles in Aedes aegypti from Iran

In this study, eight specimens were detected harbouring 1016I mutation. All specimens heterozygous for 1016I were also heterozygous for V410L. The detection of V410L and V1016I mutations in Vgsc of Ae. aegypti from Iran is the first such report from Asia. Six of eight individuals heterozygous for mutations at the 1016 position have a double-mutation 1016G/1016I genotype. This genotype has not been reported before. The sequencing results of the flanking region of the Vgsc gene of Iranian Ae. aegypti spanning 989 and 1016 positions (PCR2) are available in GenBank under the accession numbers OK236520, MZ773476 and MZ773475.

The sequencing results of the IIS6 section of the Vgsc gene of Iranian Ae. aegypti also revealed polymorphism in the intron between exons 20 and 21 including intron type A (250 bp) and intron type B (234 bp). The frequency of intron A, B and AB genotypes was 14.3%, 46.4% and 39.3% respectively (Annex 2). In this study, all six 1016G/I individuals were linked with type A intron, an association that is statistically significant (χ2 = 0.001). Intron B was observed in all specimens homozygous wild type for all kdr positions tested (χ2  = 0.001). Phylogenetic analysis was performed on the kdr mutations at S989P and V1016G/I positions of the Vgsc gene. The result of the analysis in the form of the phylogenetic tree is presented in Fig. 9. All sequences harbouring the 989P and 1016G/I kdr mutations fell into the branch containing intron type A. The sequence of 1016I kdr mutation of the Iranian population of Ae. aegypti fell in the clade of sequences available in GenBank all from the Americas.

Fig. 9
figure 9

Phylogenetic tree of the kdr mutations at S989P and V1016G/I positions of the Vgsc gene of Aedes aegypti from Iran

Discussion

Five kdr mutations including V410L, S989P, V1016G, V1016I and F1534C were detected in Iranian Ae. aegypti with different frequencies. For an invasive species that has not been under severe and long enough local selection pressure to generate in situ kdr mutations [50], the overall frequencies of the kdr mutations are considerable, raising concern about the effectiveness of pyrethroid insecticide-based interventions. The relatively high frequency of the S989P + V1016G/I haplotype on its own or in combination with V410L and F1534C confers high pyrethroid insecticide resistance [15, 17], which may lead to operational failure of these insecticides against Ae. aegypti under field conditions. A combination of 989P + 1016G confers about fivefold deltamethrin resistance compared with 1016G alone, and that combination of triple kdr mutation 989P + 1016G/I + 1534C exerts even stronger resistance to pyrethroids (50-fold) in Ae. aegypti. Space spraying when the population is triple heterozygous kdr mutant S989P + V1016G/I + F1534C may also fail [26]. These findings are also backed by studies on Ae. aegypti from other countries [39, 41, 50, 65]. V410L is also a potent kdr mutation which leads to pyrethroid insecticide resistance on its own and even more so when combined with other kdr mutations [33, 34].

The fact that about 70% of the specimens of Ae. aegypti from Iran were either heterozygous or homozygous for all four kdr mutations studied, is a cause for concern regarding the control of Ae. aegypti using pyrethroid insecticides in Iran. This part of the results corroborates with similar studies on Ae. aegypti in the world where about the same frequencies of kdr mutations caused high pyrethroid insecticides resistance [17, 21, 66,67,68]. The frequency of the F1534C mutation was higher than other kdr mutations in our study. Considering the correlation between this kdr mutation and DDT/permethrin resistance, and also noting that the frequencies of F1534C and 1534C were 57% and 9% in this study, it can be concluded that the resistance to permethrin should be high in Iranian Ae. aegypti [16, 17, 21, 24, 53, 69]. On the other hand, apart from 1016G, which is pivotal in pyrethroid resistance on its own [32], haplotypes harbouring triple mutations of S989P, V1016G/I and F1534C showed a frequency of 45% with implication in pyrethroid insecticide resistance. In addition, V410L with a frequency of about 20% exacerbates the pyrethroid insecticide resistance levels [16, 17, 28, 30, 33, 70, 71]. In other words, only < 30% of the specimens were homozygote wild type for all kdr positions studied, which means that the development of pyrethroid insecticide resistance started long ago in Iranian Ae. aegypti. As the species has recently invaded Iran and not been under long local selection pressure, this relatively high frequency of kdr mutations reveals that the evolution of resistance to pyrethroid insecticides might have been started in the ultimate country of origin of the mosquito. Not only the frequency of the F1534C mutation is higher than for the rest of the mutations, but about 9% of the specimens were homozygous for 1534C. These statistics indicate that the development of the F1534C mutation either started earlier or at a faster pace than the rest of the mutations [54]. In India, a new T1520I mutation was recently identified along with F1534C, which might have an enhancing effect on F1534C regarding protection against permethrin [22, 54, 72].

Six different haplotypes, VSVF, VSVC, LSVF, LSIF, VPGC and LPGC, were detected in this study; except for one (VSVF), the rest harbour at least one kdr mutation. The sum of the frequency of the haplotypes containing at least one kdr mutation is about 50%, which is high enough to exert a rather strong pyrethroid insecticide resistance in Iranian Ae. aegypti. Notably, the LPGC haplotype, which was detected in this study with rather high frequency, has not been reported in any kdr studies worldwide [16]. Different haplotypes confer differentially to pyrethroid insecticide resistance. Haplotypes harbouring V410L mutation either alone or in combination with the F1534C were strongly associated with increased resistance to type I and especially II pyrethroids. The order of haplotypes exerting permethrin resistance is 410L + 1534C > 410L > 1534C, and concerning deltamethrin resistance, the order is 410L = 410L + 1534C >  > 1534C [33].

For the first time in Asia, the of V410L and V1016I mutations in Vgsc gene were detected in Ae. aegypti from Iran. Although V410L and V1016I mutations have been reported in multiple African countries [17, 41, 49,50,51,52,53], Iran has limited or no maritime/air connections with those West African countries. Contrarily, in the recent decades, the country has expanded its trade and travel to the Americas. As most of the populations harbouring these mutations have their origin in the Americas, it can cautiously be concluded that the newly established Iranian population of Ae. aegypti might have the same origin. Many believe that V410L and V1016I mutations detected in Africa are due to mosquitoes brought back from Latin America just like the triangular Atlantic trips between Europe, Africa, South America and back to Europe that brought Ae. aegypti to Europe in the 1800s [22, 72]. Nonetheless, an African origin for Iranian Ae. aegypti cannot be confidently ruled out pending further molecular and population genetics studies. Iran and Pakistan have a common border of about 900 km; noting the presence of Ae. aegypti throughout Pakistan makes this country one of the prime places from which the mosquito would be expected to enter Iran. In recent studies in Pakistan, no kdr mutations were identified in sequencing the IS6 and IIS6 regions of the Vgsc gene of Ae. aegypti specimens [20, 73], whereas in our study, a relatively high frequency of mutation in IS6 and IIS6 has been found, results that probably rule out the Pakistani origin of Iranian Ae. aegypti. In a study using COI sequencing, the origin of Iranian Ae. aegypti was claimed to be Kenya or Panama [61]. However, the result is not well supported by a rather short length (310-bp) COI gene amplified from a single mosquito specimen [61].

Another very important observation of this study is that six out of eight heterozygote individuals for mutation at the 1016 position have a double-mutation 1016G/1016I genotype. This genotype has not been reported before. As V1016I has so far been reported mainly from the Americas and V1016G mainly from Asia, this discovery may indicate that the population of Ae. aegypti from Bandar Lengeh is the result of two different introductions, one from Asia and one from the Americas (or less likely from Africa), and the reproduction of the two populations yielded the hybrid genotype form of 1016G/1016I. As the discovery of V410L and V1016I mutations in our study is new to Asia and also because the 1016G/I mutation has not been reported in any Ae. aegypti populations worldwide, more molecular and population genetic studies are required to elucidate their formation.

Apart from the merit of the detection of V410L and V1016I kdr mutations in indicating the origin of the Iranian Ae. aegypti, phylogenetic analysis of the kdr mutations at S989P and V1016G/I positions obtained in our study may also serve the purpose. First, based on the available sequences in GenBank, all the populations with those kdr mutations have type A intron regardless of the geographical origin [17, 39]; second, the clade harbouring 1016I sequences is mostly from Latin America.

Conclusions

The results of this molecular study revealed relatively high frequencies of kdr mutations V410L, S989P, V1016G/I and F1534C in the newly invaded Iranian population of Ae. aegypti. The frequencies as well as the correlation/co-occurrence between these mutations are indicative of a relatively high impact on the effectiveness of pyrethroid-based chemical control interventions against Ae. aegypti in Iran. Therefore, emphasis is as always put on non-chemical interventions like environmental management and source reduction, and where chemical control measures are inevitable, non-pyrethroid insecticides or two-in-one (pyrethroid + non-pyrethroid) formulations are strongly recommended in line with insecticide resistance management principals. Further investigation of the dimensions and operational impact of insecticide resistance in Ae. aegypti from Iran including bioassays for determination of the frequency and intensity of resistance to different insecticides, biochemical and more in-depth molecular studies are recommended. The discovery of 11 specimens with V410L and 8 individuals with 1016I mutations that have so far not been reported in Asia, but are common in the Americas, may provide indications that the Iranian Ae. aegypti might have originated from the Americas; more population genetics studies on a higher number of specimens are recommended to further investigate this hypothesis.

Data availability

The data supporting the findings of the study must be available within the article and/or its supplementary materials, or deposited in a publicly available database.

References

  1. WHO. Global strategy for dengue prevention and control 2012–2020. 2012.

  2. Paixão ES, Teixeira MG, Rodrigues LC. Zika, chikungunya and dengue: the causes and threats of new and re-emerging arboviral diseases. BMJ Glob Health. 2018;3:e000530.

    Article  PubMed  PubMed Central  Google Scholar 

  3. Liu-Helmersson J, Brännström Å, Sewe MO, Semenza JC, Rocklöv J. Estimating past, present, and future trends in the global distribution and abundance of the arbovirus vector Aedes aegypti under climate change scenarios. Front Public Health. 2019;7:148.

    Article  PubMed  PubMed Central  Google Scholar 

  4. Ducheyne E, Minh NNT, Haddad N, Bryssinckx W, Buliva E, Simard F, et al. Current and future distribution of Aedes aegypti and Aedes albopictus (Diptera: Culicidae) in WHO Eastern Mediterranean Region. Int J Health Geogr. 2018;17:4.

    Article  PubMed  PubMed Central  Google Scholar 

  5. ECDC. Aedes albopictus - current known distribution: January 2019. 2019 https://www.ecdc.europa.eu/en/publications-data/aedes-albopictus-current-known-distribution-january-2019. Accessed 17 Dec 2019.

  6. Badar N, Salman M, Ansari J, Ikram A, Qazi J, Alam MM. Epidemiological trend of chikungunya outbreak in Pakistan: 2016–2018. PloS Negl Trop Dis. 2019;13:e0007118.

    Article  PubMed  PubMed Central  Google Scholar 

  7. Khan J, Khan I, Ghaffar A, Khalid B. Epidemiological trends and risk factors associated with dengue disease in Pakistan (1980–2014): a systematic literature search and analysis. BMC Public Health. 2018;18:745.

    Article  PubMed  PubMed Central  Google Scholar 

  8. Sahak MN. Dengue fever as an emerging disease in Afghanistan: epidemiology of the first reported cases. Int J Infect Dis. 2020;99:23–7.

    Article  PubMed  Google Scholar 

  9. Hussain R, Alomar I, Memish Z. Chikungunya virus: emergence of an arthritic arbovirus in Jeddah, Saudi Arabia. East Mediterr Health J. 2013;19:506–8.

    Article  CAS  PubMed  Google Scholar 

  10. Al-Tawfiq JA, Memish ZA. Dengue hemorrhagic fever virus in Saudi Arabia: a review. Vector-Borne Zoonotic Dis. 2018;18:75–81.

    Article  PubMed  Google Scholar 

  11. Alghazali K, Teoh B-T, Loong S-K, Sam S-S, Samsudin N-I, Yaacob C-N, et al. Dengue outbreak during ongoing civil war, Taiz, Yemen. Emerg Infect Dis. 2019;25:1397.

    Article  PubMed  PubMed Central  Google Scholar 

  12. Al-Abri SS, Kurup PJ, Al Manji A, Al Kindi H, Al Wahaibi A, Al Jardani A, et al. Control of the 2018–2019 dengue fever outbreak in Oman: a country previously without local transmission. Int J Infect Dis. 2020;90:97–103.

    Article  PubMed  Google Scholar 

  13. Zaim M, Enayati A, Sedaghat M, Gouya M. Guidelines for prevention and control of Aedes aegypti and Aedes albopictus in Iran. Tehran: Iran Ministry of Health and Medical Education. Virast Pub; 2020. p. 91.

    Google Scholar 

  14. Smith LB, Kasai S, Scott JG. Pyrethroid resistance in Aedes aegypti and Aedes albopictus: important mosquito vectors of human diseases. Pestic Biochem Physiol. 2016;133:1–12.

    Article  CAS  PubMed  Google Scholar 

  15. Moyes CL, Vontas J, Martins AJ, Ng LC, Koou SY, Dusfour I, et al. Contemporary status of insecticide resistance in the major Aedes vectors of arboviruses infecting humans. PLoS Negl Trop Dis. 2017;11:e0005625.

    Article  PubMed  PubMed Central  Google Scholar 

  16. Silva JJ, Kouam CN, Scott JG. Levels of cross-resistance to pyrethroids conferred by the Vssc knockdown resistance allele 410L+ 1016I+ 1534C in Aedes aegypti. PLoS Negl Trop Dis. 2021;15:e0009549.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  17. Fan Y, O’Grady P, Yoshimizu M, Ponlawat A, Kaufman PE, Scott JG. Evidence for both sequential mutations and recombination in the evolution of kdr alleles in Aedes aegypti. PLoS Negl Trop Dis. 2020;14:e0008154.

    Article  PubMed  PubMed Central  Google Scholar 

  18. Dafalla O, Alsheikh A, Mohammed W, Shrwani K, Alsheikh F, Hobani Y, et al. Knockdown resistance mutations contributing to pyrethroid resistance in Aedes aegypti population, Saudi Arabia. East Mediterr Health J. 2019;25:905–13.

    Article  PubMed  Google Scholar 

  19. Al Nazawi AM, Aqili J, Alzahrani M, McCall PJ, Weetman D. Combined target site (kdr) mutations play a primary role in highly pyrethroid resistant phenotypes of Aedes aegypti from Saudi Arabia. Parasit Vectors. 2017;10:1–10.

    Article  Google Scholar 

  20. Rahman RU, Souza B, Uddin I, Carrara L, Brito LP, Costa MM, et al. Insecticide resistance and underlying targets-site and metabolic mechanisms in Aedes aegypti and Aedes albopictus from Lahore. Pakistan Sci Rep. 2021;11:1–15.

    Google Scholar 

  21. Muthusamy R, Shivakumar M. Involvement of metabolic resistance and F1534C kdr mutation in the pyrethroid resistance mechanisms of Aedes aegypti in India. Acta Trop. 2015;148:137–41.

    Article  CAS  PubMed  Google Scholar 

  22. Kushwah RBS, Dykes CL, Kapoor N, Adak T, Singh OP. Pyrethroid-resistance and presence of two knockdown resistance (kdr) mutations, F1534C and a novel mutation T1520I, in Indian Aedes aegypti. PLoS Negl Trop Dis. 2015;9:e3332.

    Article  PubMed  PubMed Central  Google Scholar 

  23. Kushwah RBS, Kaur T, Dykes CL, Kumar RH, Kapoor N, Singh OP. A new knockdown resistance (kdr) mutation F1534L in Aedes aegypti associated with insecticide resistance. bioRxiv. 2019:740829.

  24. Fernando SD, Hapugoda M, Perera R, Saavedra-Rodriguez K, Black WC, De Silva NK. First report of V1016G and S989P knockdown resistant (kdr) mutations in pyrethroid-resistant Sri Lankan Aedes aegypti mosquitoes. Parasit Vectors. 2018;11:1–6.

    Article  Google Scholar 

  25. Saingamsook J, Saeung A, Yanola J, Lumjuan N, Walton C, Somboon P. A multiplex PCR for detection of knockdown resistance mutations, V1016G and F1534C, in pyrethroid-resistant Aedes aegypti. Parasit Vectors. 2017;10:1–9.

    Article  Google Scholar 

  26. Plernsub S, Saingamsook J, Yanola J, Lumjuan N, Tippawangkosol P, Sukontason K, et al. Additive effect of knockdown resistance mutations, S989P, V1016G and F1534C, in a heterozygous genotype conferring pyrethroid resistance in Aedes aegypti in Thailand. ParasitVectors. 2016;9:1–7.

    Google Scholar 

  27. Stenhouse SA, Plernsub S, Yanola J, Lumjuan N, Dantrakool A, Choochote W, et al. Detection of the V1016G mutation in the voltage-gated sodium channel gene of Aedes aegypti (Diptera: Culicidae) by allele-specific PCR assay, and its distribution and effect on deltamethrin resistance in Thailand. Parasit Vectors. 2013;6:1–10.

    Article  Google Scholar 

  28. Ishak IH, Jaal Z, Ranson H, Wondji CS. Contrasting patterns of insecticide resistance and knockdown resistance (kdr) in the dengue vectors Aedes aegypti and Aedes albopictus from Malaysia. Parasit Vectors. 2015;8:1–13.

    Article  Google Scholar 

  29. Abu Bakar A, Ahmad Mokhtar A, Mat Jusoh TNA, Shueb RH. Evaluation of the DDT and pyrethroid resistance status of Aedes aegypti (Linnaeus)(Diptera: Culicidae) in Kota Bharu, Kelantan. Trans Sci Technol. 2021;8:128–36.

    Google Scholar 

  30. Akhir MAM, Wajidi MF, Lavoué S, Azzam G, Jaafar IS, Awang Besar NAU, et al. Knockdown resistance (kdr) gene of Aedes aegypti in Malaysia with the discovery of a novel regional specific point mutation A1007G. Parasit Vectors. 2022;15:1–15.

    Article  Google Scholar 

  31. Amelia-Yap ZH, Sofian-Azirun M, Chen CD, Lau KW, Suana IW, Syahputra E, et al. V1016G point mutation: the key mutation in the voltage-gated sodium channel (Vgsc) gene of pyrethroid-resistant Aedes aegypti (Diptera: Culicidae) in Indonesia. J Med Entomol. 2019;56:953–8.

    CAS  PubMed  Google Scholar 

  32. Hamid PH, Prastowo J, Widyasari A, Taubert A, Hermosilla C. Knockdown resistance (kdr) of the voltage-gated sodium channel gene of Aedes aegypti population in Denpasar, Bali, Indonesia. Parasit Vectors. 2017;10:1–9.

    Article  Google Scholar 

  33. Haddi K, Tomé HVV, Du Y, Valbon WR, Nomura Y, Martins GF, et al. Detection of a new pyrethroid resistance mutation (V410L) in the sodium channel of Aedes aegypti: a potential challenge for mosquito control. Sci Rep. 2017;7:46549.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  34. Hernandez JR, Liu S, Fredregill CL, Pietrantonio PV. Impact of the V410L kdr mutation and co-occurring genotypes at kdr sites 1016 and 1534 in the VGSC on the probability of survival of the mosquito Aedes aegypti (L.) to Permanone in Harris County, TX, USA. PLoS Negl Trop Dis. 2023;17:e0011033. https://doi.org/10.1371/journal.pntd.0011033.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  35. Ayres CF, Seixas G, Borrego S, Marques C, Monteiro I, Marques CS, et al. The V410L knockdown resistance mutation occurs in island and continental populations of Aedes aegypti in West and Central Africa. PLoS Negl Trop Dis. 2020;14:e0008216.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  36. Brengues C, Hawkes NJ, Chandre F, McCarroll L, Duchon S, Guillet P, et al. Pyrethroid and DDT cross-resistance in Aedes aegypti is correlated with novel mutations in the voltage-gated sodium channel gene. Med Vet Entomol. 2003;17:87–94.

    Article  CAS  PubMed  Google Scholar 

  37. Wuliandari JR, Lee SF, White VL, Tantowijoyo W, Hoffmann AA, Endersby-Harshman NM. Association between three mutations, F1565C, V1023G and S996P, in the voltage-sensitive sodium channel gene and knockdown resistance in Aedes aegypti from Yogyakarta. Indonesia Insects. 2015;6:658–85.

    Article  PubMed  Google Scholar 

  38. Kawada H, Oo SZM, Thaung S, Kawashima E, Maung YNM, Thu HM, et al. Co-occurrence of point mutations in the voltage-gated sodium channel of pyrethroid-resistant Aedes aegypti populations in Myanmar. PLoS Negl Trop Dis. 2014;8:e3032.

    Article  PubMed  PubMed Central  Google Scholar 

  39. Chung H-H, Cheng I-C, Chen Y-C, Lin C, Tomita T, Teng H-J. Voltage-gated sodium channel intron polymorphism and four mutations comprise six haplotypes in an Aedes aegypti population in Taiwan. PLoS Negl Trop Dis. 2019;13:e0007291.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  40. Saha P, Chatterjee M, Ballav S, Chowdhury A, Basu N, Maji AK. Prevalence of kdr mutations and insecticide susceptibility among natural population of Aedes aegypti in West Bengal. PLoS One. 2019;14:e0215541.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  41. Kawada H, Higa Y, Futami K, Muranami Y, Kawashima E, Osei JH, et al. Discovery of point mutations in the voltage-gated sodium channel from African Aedes aegypti populations: potential phylogenetic reasons for gene introgression. PLos Negl Trop Dis. 2016;10:e0004780.

    Article  PubMed  PubMed Central  Google Scholar 

  42. Alvarez LC, Ponce G, Saavedra-Rodriguez K, Lopez B, Flores AE. Frequency of V1016I and F1534C mutations in the voltage-gated sodium channel gene in Aedes aegypti in Venezuela. Pest Manag Sci. 2015;71:863–9.

    Article  CAS  PubMed  Google Scholar 

  43. Saavedra-Rodriguez K, Urdaneta-Marquez L, Rajatileka S, Moulton M, Flores A, Fernandez-Salas I, et al. A mutation in the voltage-gated sodium channel gene associated with pyrethroid resistance in Latin American Aedes aegypti. Insect Mol Biol. 2007;16:785–98.

    Article  CAS  PubMed  Google Scholar 

  44. Aguirre-Obando OA, Bona ACD, Duque LJE, Navarro-Silva MA. Insecticide resistance and genetic variability in natural populations of Aedes (Stegomyia) aegypti (Diptera: Culicidae) from Colombia. Zoologia (Curitiba). 2015;32:14–22.

    Article  Google Scholar 

  45. García GP, Flores AE, Fernández-Salas I, Saavedra-Rodríguez K, Reyes-Solis G, Lozano-Fuentes S, et al. Recent rapid rise of a permethrin knock down resistance allele in Aedes aegypti in Mexico. PLoS Negl Trop Dis. 2009;3:e531.

    Article  PubMed  PubMed Central  Google Scholar 

  46. Cornel AJ, Holeman J, Nieman CC, Lee Y, Smith C, Amorino M, et al. Surveillance, insecticide resistance and control of an invasive Aedes aegypti (Diptera: Culicidae) population in California. F1000Research. 2016;5:194.

    Article  PubMed  PubMed Central  Google Scholar 

  47. Vickers NJ. Animal communication: when i’m calling you, will you answer too? Curr Biol. 2017;27:R713–5.

    Article  CAS  PubMed  Google Scholar 

  48. Vera-Maloof FZ, Saavedra-Rodriguez K, Elizondo-Quiroga AE, Lozano-Fuentes S, Black WC IV. Coevolution of the Ile 1, 016 and Cys1, 534 mutations in the voltage gated sodium channel gene of Aedes aegypti in Mexico. PLoS Negl Trop Dis. 2015;9:e0004263.

    Article  PubMed  PubMed Central  Google Scholar 

  49. Campos M, Ward D, Morales RF, Gomes AR, Silva K, Sepúlveda N, et al. Surveillance of Aedes aegypti populations in the city of Praia, Cape Verde: Zika virus infection, insecticide resistance and genetic diversity. Parasit Vectors. 2020;13:1–11.

    Article  Google Scholar 

  50. Cosme LV, Gloria-Soria A, Caccone A, Powell JR, Martins AJ. Evolution of kdr haplotypes in worldwide populations of Aedes aegypti: independent origins of the F1534C kdr mutation. PLoS Negl Trop Dis. 2020;14:e0008219.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  51. Sombié A, Saiki E, Yaméogo F, Sakurai T, Shirozu T, Fukumoto S, et al. High frequencies of F1534C and V1016I kdr mutations and association with pyrethroid resistance in Aedes aegypti from Somgandé (Ouagadougou), Burkina Faso. Trop Med Health. 2019;47:1–8.

    Article  Google Scholar 

  52. Badolo A, Sombié A, Pignatelli PM, Sanon A, Yaméogo F, Wangrawa DW, et al. Insecticide resistance levels and mechanisms in Aedes aegypti populations in and around Ouagadougou, Burkina Faso. PLoS Negl Trop Dis. 2019;13:e0007439.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  53. Seixas G, Grigoraki L, Weetman D, Vicente JL, Silva AC, Pinto J, et al. Insecticide resistance is mediated by multiple mechanisms in recently introduced Aedes aegypti from Madeira Island (Portugal). PLoS Negl Trop Dis. 2017;11:e0005799.

    Article  PubMed  PubMed Central  Google Scholar 

  54. Chen M, Du Y, Wu S, Nomura Y, Zhu G, Zhorov BS, et al. Molecular evidence of sequential evolution of DDT-and pyrethroid-resistant sodium channel in Aedes aegypti. PLOS Negl Trop Dis. 2019;13:e0007432.

    Article  PubMed  PubMed Central  Google Scholar 

  55. Saavedra-Rodriguez K, Maloof FV, Campbell CL, Garcia-Rejon J, Lenhart A, Penilla P, et al. Parallel evolution of vgsc mutations at domains IS6, IIS6 and IIIS6 in pyrethroid resistant Aedes aegypti from Mexico. Sci Rep. 2018;8:1–9.

    Article  Google Scholar 

  56. Plernsub S, Saingamsook J, Yanola J, Lumjuan N, Tippawangkosol P, Walton C, et al. Temporal frequency of knockdown resistance mutations, F1534C and V1016G, in Aedes aegypti in Chiang Mai city, Thailand and the impact of the mutations on the efficiency of thermal fogging spray with pyrethroids. Acta Trop. 2016;162:125–32.

    Article  CAS  PubMed  Google Scholar 

  57. Hirata K, Komagata O, Itokawa K, Yamamoto A, Tomita T, Kasai S. A single crossing-over event in voltage-sensitive Na+ channel genes may cause critical failure of dengue mosquito control by insecticides. PLoS Negl Trop Dis. 2014;8:e3085.

    Article  PubMed  PubMed Central  Google Scholar 

  58. Dow E. Notes on Iranian mosquitoes. Am J Trop Med Hyg. 1953;2:683–95.

    Article  CAS  PubMed  Google Scholar 

  59. Edwards FW. A revision of the mosquitos of the Palaearctic region. Bull Entomol Res. 1921;12:263–351.

    Article  Google Scholar 

  60. Kraemer MU, Sinka ME, Duda KA, Mylne AQ, Shearer FM, Barker CM, et al. The global distribution of the arbovirus vectors Aedes aegypti and Ae. albopictus. Elife. 2015;4:e08347.

    Article  PubMed  PubMed Central  Google Scholar 

  61. Dorzaban H, Soltani A, Alipour H, Hatami J, Jaberhashemi SA, Shahriari-Namadi M, et al. Mosquito surveillance and the first record of morphological and molecular-based identification of invasive species Aedes (Stegomyia) aegypti (Diptera: Culicidae), southern Iran. Exp Parasitol. 2022;236–237:108235. https://doi.org/10.1016/j.exppara.2022.108235.

    Article  CAS  PubMed  Google Scholar 

  62. Livak KJ. Organization and mapping of a sequence on the Drosophila melanogaster X and Y chromosomes that is transcribed during spermatogenesis. Genetics. 1984;107:611–34.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  63. Safi NHZ, Ahmadi AA, Nahzat S, Warusavithana S, Safi N, Valadan R, et al. Status of insecticide resistance and its biochemical and molecular mechanisms in Anopheles stephensi (Diptera: Culicidae) from Afghanistan. Malar J. 2019;18:1–12.

    Article  Google Scholar 

  64. Harris AF, Rajatileka S, Ranson H. Pyrethroid resistance in Aedes aegypti from Grand Cayman. Am J Trop Med Hyg. 2010;83:277.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  65. Martins AJ, Lins RMMA, Linss JGB, Peixoto AA, Valle D. Voltage-gated sodium channel polymorphism and metabolic resistance in pyrethroid-resistant Aedes aegypti from Brazil. Am J Trop Med Hyg. 2009;81:108–15.

    Article  CAS  PubMed  Google Scholar 

  66. Yougang AP, Kamgang B, Bahun TAW, Tedjou AN, Nguiffo-Nguete D, Njiokou F, et al. First detection of F1534C knockdown resistance mutation in Aedes aegypti (Diptera: Culicidae) from Cameroon. Infect Dis Poverty. 2020;9:51–62.

    Article  Google Scholar 

  67. Linss JGB, Brito LP, Garcia GA, Araki AS, Bruno RV, Lima JBP, et al. Distribution and dissemination of the Val1016Ile and Phe1534Cys kdr mutations in Aedes aegypti Brazilian natural populations. Parasit Vectors. 2014;7:1–11.

    Article  Google Scholar 

  68. Kasai S, Caputo B, Tsunoda T, Cuong TC, Maekawa Y, Lam-Phua SG, et al. First detection of a Vssc allele V1016G conferring a high level of insecticide resistance in Aedes albopictus collected from Europe (Italy) and Asia (Vietnam), 2016: a new emerging threat to controlling arboviral diseases. Euro Surveill. 2019;24:1700847.

    Article  PubMed  PubMed Central  Google Scholar 

  69. Pinto J, Palomino M, Mendoza-Uribe L, Sinti C, Liebman KA, Lenhart A. Susceptibility to insecticides and resistance mechanisms in three populations of Aedes aegypti from Peru. Parasit Vectors. 2019;12:1–11.

    Article  CAS  Google Scholar 

  70. Itokawa K, Furutani S, Takaoka A, Maekawa Y, Sawabe K, Komagata O, et al. A first, naturally occurring substitution at the second pyrethroid receptor of voltage-gated sodium channel of Aedes aegypti. Pest Manag Sci. 2021;77:2887–93.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  71. Hernandez JR, Longnecker M, Fredregill CL, Debboun M, Pietrantonio PV. Kdr genotyping (V1016I, F1534C) of the Nav channel of Aedes aegypti (L.) mosquito populations in Harris County (Houston), Texas, USA, after Permanone 31–66 field tests and its influence on probability of survival. PLoS Negl Trop Dis. 2021;15:e0009833.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  72. Powell JR, Gloria-Soria A, Kotsakiozi P. Recent history of Aedes aegypti: vector genomics and epidemiology records. Bioscience. 2018;68:854–60.

    Article  PubMed  PubMed Central  Google Scholar 

  73. Ramzan H, Manzoor F, Oneeb M. Current status of insecticide resistance and its underlying mechanisms in Aedes aegypti (L.) in Punjab, Pakistan. J Vector Borne Dis. 2023;60:57–64.

    CAS  PubMed  Google Scholar 

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Acknowledgements

The authors extend their gratitude to the World Health Organization for supporting this research project. Also, many thanks to the Vector Borne Diseases Control Department, CDC, Ministry of Health and Medical Education, Iran, for the support. Thanks also to the Vice Chancellor for Research and Technology of Mazandaran University of Medical Sciences for partial financial support. We also thank Jafar Hatami, Masoud Yeryan, Abdolrahim Cheshmpoushan, Abdolrasoul Mojahedi, Arash Alvandi, Kaveh Soleimani, Morteza Salemi, Tayebeh Raznahan, Asadollah Ahmadi and Abdoljabbar Zakeri for their role in Aedes aegypti surveillance and sample collection in Hormozgan Province, Iran.

Funding

This work was supported by the Research Vice-Chancellor of Mazandaran University of Medical Sciences (Grant Number 14893) and the the World Health Organization (Grant Number 207243).

Author information

Authors and Affiliations

Authors

Contributions

AE conceptualized the research and wrote the manuscript; MB and MC were involved in the laboratory work; SHN, MFD and NHV were involved in the species identification, laboratory work and data analyses; FS and RSK conducted the molecular laboratory work; AR, FN and AM supported and supervised the field work and sample collection; FB conducted the field work and collected the specimens; MMS and MZ were involved in conceptualizing the research and edited the manuscript; RV supervised the laboratory work and analysed the sequencing and phylogenetic data; DW and JH were involved in the conceptualization of the research and critically reviewed the manuscript.

Corresponding author

Correspondence to Ahmadali Enayati.

Ethics declarations

Ethics approval and consent to participate

Not applicable.

Consent for publication

Not applicable.

Competing interests

The authors declare that they have no conflict of interest.

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Appendices

Appendices

Appendix 1

The coordinates of the sampling places and the number of eggs, larvae, pupae and adults collected during 2020

 

Latitude

Longitude

Egg

Larva

Pupa

Adult

1

26° 33′ 53.07"

54° 53′ 29.57"

0

2

0

0

2

26° 32′ 57.29"

54° 53′ 00.67"

82

0

0

4

3

26° 35′ 35.48"

54° 55′ 59.00"

0

0

0

1

4

26° 32′ 39.29"

54° 52′ 31.16"

25

4

2

0

5

26° 33′ 3.39"

54° 53′ 10.28"

135

3

0

0

6

26° 32′ 36.58"

54° 52′ 27.19"

3

6

0

0

7

26° 35′ 20.41"

54° 56′ 11.04"

33

4

0

0

8

26° 33′ 06.01"

54° 51′ 59.1"

0

4

0

0

9

26° 34′ 21.10"

54° 53′ 33.35"

0

5

0

0

10

26° 32′ 46.65"

54° 52′ 40.74"

29

12

0

0

Sum

  

307

40

2

5

Appendix 2

List of kdr mutations and genotypes in association with the intron type in Vgsc gene of Aedes aegypti from Iran

No.

Specimen code

V410L

F989P

V1016G

V1016I

F1534C

Intron

Genotype

1

1

W

W

W

–

W

B

V410/S989/V1016/F1534

2

7

W

W

W

–

W

B

V410/S989/V1016/F1534

3

L4

W

W

W

–

W

B

V410/S989/V1016/F1534

4

L6

W

W

W

–

W

B

V410/S989/V1016/F1534

5

L9

W

W

W

–

W

B

V410/S989/V1016/F1534

6

L26

W

W

W

–

W

B

V410/S989/V1016/F1534

7

L29

W

W

W

–

W

B

V410/S989/V1016/F1534

8

L30

W

W

W

–

W

B

V410/S989/V1016/F1534

9

L34

W

W

W

–

W

B

V410/S989/V1016/F1534

10

L35

W

W

W

–

W

B

V410/S989/V1016/F1534

11

L36

W

W

W

–

W

B

V410/S989/V1016/F1534

12

L38

W

W

W

–

W

B

V410/S989/V1016/F1534

13

L45

W

W

W

–

W

B

V410/S989/V1016/F1534

14

L47

W

W

W

–

W

B

V410/S989/V1016/F1534

15

L53

W

W

W

–

W

B

V410/S989/V1016/F1534

16

L55

W

W

W

–

W

B

V410/S989/V1016/F1534

17

L18

W

W

W

–

H

B

V410/S989/V1016/F1534C

18

L19

W

W

W

–

H

B

V410/S989/V1016/F1534C

19

L1

W

W

W

–

H

B

V410/S989/V1016/F1534C

20

L5

W

W

W

–

H

B

V410/S989/V1016/F1534C

21

L42

W

W

W

–

H

B

V410/S989/V1016/F1534C

22

L49

W

W

W

–

H

B

V410/S989/V1016/F1534C

23

L52

W

W

W

–

H

B

V410/S989/V1016/F1534C

24

L27

W

W

W

–

M

B

V410/S989/V1016/1534C

25

L54

W

W

W

–

M

B

V410/S989/V1016/1534C

26

L28

W

H

H

–

H

AB

V410/S989P/V1016G/F1534C

27

2

W

H

H

–

H

AB

V410/S989P/V1016G/F1534C

28

8

W

H

H

–

H

AB

V410/S989P/V1016G/F1534C

29

3

W

H

H

–

H

AB

V410/S989P/V1016G/F1534C

30

L31

W

H

H

–

H

AB

V410/S989P/V1016G/F1534C

31

L32

W

H

H

–

H

AB

V410/S989P/V1016G/F1534C

32

L33

W

H

H

–

H

AB

V410/S989P/V1016G/F1534C

33

L40

W

H

H

–

H

AB

V410/S989P/V1016G/F1534C

34

L14

W

H

H

–

H

AB

V410/S989P/V1016G/F1534C

35

L43

W

H

H

–

H

AB

V410/S989P/V1016G/F1534C

36

L44

W

H

H

–

H

AB

V410/S989P/V1016G/F1534C

37

5

W

H

H

–

H

AB

V410/S989P/V1016G/F1534C

38

L15

W

H

H

–

H

AB

V410/S989P/V1016G/F1534C

39

L51

W

H

H

–

H

AB

V410/S989P/V1016G/F1534C

40

L10

W

H

H

–

H

AB

V410/S989P/V1016G/F1534C

41

L11

W

H

H

–

H

AB

V410/S989P/V1016G/F1534C

42

L56

W

H

H

–

H

AB

V410/S989P/V1016G/F1534C

43

L13

W

M

M

–

M

A

V410/989P/1016G/1534C

44

L46

W

M

M

–

M

A

V410/989P/1016G/1534C

45

6

W

H

H

–

M

AB

V410/S989P/V1016G/1534C

46

4

H

W

W

–

W

B

V410L/S989/V1016/F1354

47

L48

H

W

–

H

W

AB

V410L/S989/V1016I/F1534

48

L7

H

W

–

H

W

AB

V410L/S989/V1016I/F1534

49

L41

H

H

M

M

H

A

V410L/S989P/V1016G&I/F1534C

50

L37

H

H

M

M

H

A

V410L/S989P/V1016G&I/F1534C

51

L3

H

H

M

M

H

A

V410L/S989P/V1016G&I/F1534C

52

L2

H

H

M

M

H

A

V410L/S989P/V1016G&I/F1534C

53

L50

H

H

M

M

H

A

V410L/S989P/V1016G&I/F1534C

54

L39

H

H

M

M

H

A

V410L/S989P/V1016G&I/F1534C

55

L16

H

H

H

–

H

AB

V410L/S989P/V1016G/F1534C

56

L17

H

H

H

–

H

AB

V410L/S989P/V1016G/F1534C

  1. W: wild; H: heterozygous; M: mutant

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Enayati, A., Valadan, R., Bagherzadeh, M. et al. Kdr genotyping and the first report of V410L and V1016I kdr mutations in voltage-gated sodium channel gene in Aedes aegypti (Diptera: Culicidae) from Iran. Parasites Vectors 17, 34 (2024). https://doi.org/10.1186/s13071-024-06123-w

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  • DOI: https://doi.org/10.1186/s13071-024-06123-w

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