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For attaining an entrepreneurial development of Mexico, particularly in the state of Michoacán, it is of the utmost importance to know what are the factors and elements that influence in a relevant way to generate a regional, national and international development and the positioning of the MIPYMEs (micro, small and medium enterprises, declared as - MSMEs) in the market. For this reason, in the present work, a study that incorporates the Forgotten Effects Theory (FET) is made. This theory, originally proposed by professors Kaufmann and Gil-Aluja in 1988, studies the sustainability and the good economic development of the enterprise and thus, finds all those factors that employing the classical theory are not possible to know precisely. Once determined with the FET it is possible to design more efficient and effective development plans, which will enable the sustainability of the enterprise and self-sustained development of regions and countries based on entrepreneurial development. [ABSTRACT FROM AUTHOR]

Pyrethroid resistance in Aedes aegypti has become widespread after almost two decades of frequent applications to reduce the transmission of mosquito-borne diseases. Because few insecticide classes are available for public health use, insecticide resistance management (IRM) is proposed as a strategy to retain their use. A key hypothesis of IRM assumes that negative fitness is associated with resistance, and when insecticides are removed from use, susceptibility is restored. In Tapachula, Mexico, pyrethroids (PYRs) were used exclusively by dengue control programs for 15 years, thereby contributing to selection for high PYR resistance in mosquitoes and failure in dengue control. In 2013, PYRs were replaced by organophosphates-insecticides from a class with a different mode of action. To test the hypothesis that PYR resistance is reversed in the absence of PYRs, we monitored Ae. aegypti's PYR resistance from 2016 to 2021 in Tapachula. We observed significant declining rates in the lethal concentration 50 (LC50), for permethrin and deltamethrin. For each month following the discontinuation of PYR use by vector control programs, we observed increases in the odds of mosquitoes dying by 1.5% and 8.4% for permethrin and deltamethrin, respectively. Also, knockdown-resistance mutations (kdr) in the voltage-gated sodium channel explained the variation in the permethrin LC50s, whereas variation in the deltamethrin LC50s was only explained by time. This trend was rapidly offset by application of a mixture of neonicotinoid and PYRs by vector control programs. Our results suggest that IRM strategies can be used to reverse PYR resistance in Ae. aegypti; however, long-term commitment by operational and community programs will be required for success., Competing Interests: The authors have declared that no competing interests exist., (Copyright: This is an open access article, free of all copyright, and may be freely reproduced, distributed, transmitted, modified, built upon, or otherwise used by anyone for any lawful purpose. The work is made available under the Creative Commons CC0 public domain dedication.)

Chiapas State comprises the largest malaria foci from Mexico, and 57% of the autochthonous cases in 2021, all with Plasmodium vivax infections, were reported in this State. Southern Chiapas is at constant risk of cases imported due to migratory human flow. Since chemical control of vector mosquitoes is the main entomological action implemented for the prevention and control of vector-borne diseases, this work aimed to investigate the susceptibility of Anopheles albimanus to insecticides. To this end, mosquitoes were collected in cattle in two villages in southern Chiapas in July-August 2022. Two methods were used to evaluate the susceptibility: the WHO tube bioassay and the CDC bottle bioassay. For the latter, diagnostic concentrations were calculated. The enzymatic resistance mechanisms were also analyzed. CDC diagnostic concentrations were obtained; 0.7 μg/mL deltamethrin, 12 μg/mL permethrin, 14.4 μg/mL malathion, and 2 μg/mL chlorpyrifos. Mosquitoes from Cosalapa and La Victoria were susceptible to organophosphates and to bendiocarb, but resistant to pyrethroids, with mortalities between 89% and 70% (WHO), and 88% and 78% (CDC), for deltamethrin and permethrin, respectively. High esterase levels are suggested as the resistance mechanism involved in the metabolism of pyrethroids in mosquitoes from both villages. Mosquitoes from La Victoria might also involve cytochrome P 450 . Therefore, organophosphates and carbamates are suggested to currently control An. albimanus . Its use might reduce the frequency of resistance genes to pyrethroids and vector abundance and may impede the transmission of malaria parasites.

Objective: To identify the enzyme-mediated insecticide resistance in Aedes aegypti in Tapachula, Mexico., Materials and Methods: Biochemical assays were undertaken to determine the enzyme levels in mosquitoes from 22 sites collected in 2018 and 2020 in Tapachula. Results of 2018 were correlated with the resistance to insecticides pub-lished., Results: Mosquitoes had higher levels than those of the susceptible strain in 2018 and 2020 respectively of α-esterases in 15 and 12 sites; β-esterases in 7 and 6 sites; glutathione-S-transferases in 11 and 19 sites; ρNPA-esterases in 21 and 17 sites; and cytochromes P450 in 20 and 22 sites. In mosquitoes of 2018, there was a moderate correlation between previously documented Malathion resistance ratios and the insensitive acetylcholinesterase (r=0.459, p= 0.03)., Conclusions: The elevated enzyme levels found indicate its contribution to the resistance to pyrethroids and organo-phosphates already published in mosquitoes from Tapachula. Bioassays using enzyme inhibitors resulted in greater mor-tality, confirming that metabolism contributes to resistance.

Background: Insecticide use continues as the main strategy to control Aedes aegypti, the vector of dengue, Zika, chikungunya, and yellow fever. In the city of Tapachula, Mexico, mosquito control programs switched from pyrethroids to organophosphates for outdoor spatial spraying in 2013. Additionally, the spraying scheme switched from total coverage to focused control, prioritizing areas with higher entomological-virological risk. Five years after this strategy had been implemented, we evaluated the status and variability of insecticide resistance among Ae. aegypti collected at 26 sites in Tapachula., Methodology/principal Findings: We determined the lethal concentrations at 50% of the tested populations (LC50) using a bottle bioassay, and then, we calculated the resistance ratio (RR) relative to the susceptible New Orleans strain. Permethrin and deltamethrin (pyrethroids), chlorpyrifos and malathion (organophosphates), and bendiocarb (carbamate) were tested. The frequencies of the substitutions V1016I and F1534C, which are in the voltage-gated sodium channel and confer knockdown-resistance (kdr) to pyrethroid insecticides, were calculated. Despite 5 years having passed since the removal of pyrethroids from the control programs, Ae. aegypti remained highly resistant to permethrin and deltamethrin (RR > 10-fold). In addition, following 5 years of chlorpyrifos use, mosquitoes at 15 of 26 sites showed moderate resistance to chlorpyrifos (5- to 10-fold), and the mosquitoes from one site were highly resistant. All sites had low resistance to malathion (< 5-fold). Resistance to bendiocarb was low at 19 sites, moderate at five, and high at two. Frequencies of the V1016I ranged from 0.16-0.71, while C1534 approached fixation at 23 sites (0.8-1). Resistance profiles and kdr allele frequencies varied across Tapachula. The variability was not associated with a spatial pattern at the scale of the sampling., Conclusion/significance: Mosquito populations respond to selection pressure at a focal scale in the field. Spatial variation across sites highlights the importance of testing multiple sites within geographical regions., Competing Interests: The authors have declared that no competing interests exist. Author Americo D. Rodriguez was unable to confirm their authorship contributions. On their behalf, the corresponding author has reported their contributions to the best of their knowledge.

There are major public health concerns regarding the spread of mosquito-borne diseases such as dengue, Zika, and chikungunya, which are mainly controlled by using insecticides against the vectors, Aedes aegypti (Linnaeus) and Aedes albopictus (Skuse). Pyrethroids are the primary class of insecticides used for vector control, due to their rapid knockdown effect and low toxicity to vertebrates. Unfortunately, continued use of pyrethroids has led to widespread insecticide resistance in Ae. aegypti; however, we lack information for Ae. albopictus-a sympatric species in Chiapas since 2002. In this study, we evaluated the permethrin resistance status of Ae. albopictus collected from Mexico and Texas. We also selected for permethrin resistance in the laboratory and investigated the potential mechanisms conferring resistance in this species. Knockdown resistance mutations, specifically F1534C, in the voltage-gated sodium channel gene, and increased activity of detoxifying enzymes were evaluated. Low levels of permethrin resistance (<2.4-fold) were observed in our field populations of Ae. albopictus and the F1534C mutation was not detected in any of the sites. Low levels of resistance were also observed in the artificially selected strain. There was significantly higher cytochrome P450 activity in our permethrin-selected and nonselected strains from Mexico compared to the control strain. Our results suggest the Ae. albopictus sampled from 2016 are mostly susceptible to pyrethroids. These results contrast with the high levels of permethrin resistance (>58-fold) found in Ae. aegypti from the same sites in Mexico. This research indicates the importance of continued monitoring of Ae. albopictus populations to prevent resistance from developing in the future., (© The Author(s) 2020. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

Objective: To determine the insecticide resistance status of Ae. aegypti and Ae. albopictus from Tapachula, México., Materials and Methods: Mosquito eggs were collected with the use of ovitraps and CDC susceptibility bioassays and biochemical assays were conducted to determine resistance levels and resistance mechanisms, respectively., Results: Ae. aegypti showed resistance to deltamethrin and permethrin (PYRs), malathion, chlorpyrifos and temephos (OP), and to bendiocarb (CARB), while Ae. albopictus showed resistance to malathion and to a lesser intensity to chlorypirifos, temephos, permethrin and deltamethrin. Both species showed high levels of P450 and GSTs, while levels of esterases varied by species and collection site. Altered acethilcholinesterase was detected in both species., Conclusions: In an urban habitat from Tapachula, Chiapas, Mexico where vector control using insecticides takes place, Ae. aegypti and Ae. albopictus are only susceptible to propoxur., Competing Interests: Declaration of conflict of interests. The authors declare that they have no conflict of interests.