Abstract
Dengue is one of the most serious mosquito-borne infectious diseases in the world. Aedes albopictus is the most invasive mosquito and one of the primary vectors of dengue. Vector control using insecticides is the only viable strategy to prevent dengue virus transmission. In Guangzhou, after the 2014 pandemic, massive insecticides have been implemented. Massive insecticide use may lead to the development of resistance, but few reports are available on the status of insecticide resistance in Guangzhou after 2014. In this study, Ae. albopictus were collected from four districts with varied dengue virus transmission intensity in Guangzhou from 2015 to 2017. Adult Ae. albopictus insecticide susceptibility to deltamethrin (0.03%), permethrin(0.25%), DDT(4%), malathion (0.8%) and bendiocarb (0.1%) was determined by the standard WHO tube test, and larval resistance bioassays were conducted using temephos, Bacillus thuringiensis israelensis (Bti), pyriproxyfen (PPF) and hexaflumuron. Mutations at the voltage-gated sodium channel (VGSC) gene and acetylcholinesterase (AChE) gene were analyzed. The effect of cytochrome P450s on the resistance of Ae. albopictus to deltamethrin was tested using the synergistic agent piperonyl butoxide (PBO). The results showed that Ae. albopictus populations have rapidly developed very high resistances to multiple commonly used insecticides at all study areas except malathion, Bti and hexaflumuron. We found 1534 codon mutations in the VGSC gene that were significantly correlated with the resistance to pyrethroids and DDT, and 11 synonymous mutations were also found in the gene. The resistance to deltamethrin can be significantly reduced by PBO but may generated cross-resistance to PPF. Fast emerging resistance in Ae. albopictus may affect mosquito management and threaten the prevention and control of dengue, similar to the resistance in Anopheles mosquitoes has prevented the elimination of malaria and call for timely and guided insecticide management.
Highlights
Dengue is one of the most rapidly spreading mosquito-borne diseases in the world
Regular monitoring of insecticide susceptibility is essential for insecticide resistance management
The results displayed that Ae. albopictus had rapidly generated high resistance to the most commonly used adult insecticide pyrethroid and larvicide organophosphate
Summary
Dengue is one of the most rapidly spreading mosquito-borne diseases in the world. Currently, 3.9 billion people in 128 countries or regions are at risk of dengue fever [1,2,3]. The largest city in southern China and the capital of Guangdong Province, has become the epicenter of dengue outbreaks in China. Due to the lack of effective drugs and vaccines against dengue, vector management is the main strategy to prevent and control mosquito-borne diseases, including dengue [10,11,12,13]. In China, chemical control through the use of insecticides is one of the major tools for the control of vector mosquitoes [14, 15]. During the outbreak of dengue in Guangzhou in 2014, more than 27,000 kg of pyrethroids were used for ultralow-volume (ULV) spraying to control adult Ae. albopictus, and a large amount of temephos, an organophosphate larvicide, was used for larval control.
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
