Virus-transmitting mosquitoes in Asia evolving to grow resistant to insecticides: Study
Researchers say that virus transmitting mosquitoes in Asia are evolving to grow resistant to insecticides now they warn that there is an urgent need for novel ways to control its population the study discovered a series of mutations that made mosquitoes impervious to popular insecticide chemicals now this species variant was.
Found in more than 90 percent of 80s egypti mosquitoes in Cambodia granting them extremely high levels of resistance study ones that commonly employed strategies May no longer be effective in controlling the mosquito population and for more on this we’re joined by Tiki Pang he’s visiting professor at Young lulin School of Medicine good.
Evening Professor pong it appears that aedes aegypti the species of mosquito that we know carries yellow fever Dengue as well as zika it just got more dangerous perhaps How concerned should we be though that this newly identified mutant combination represents a greater threat to communities or or even has greater potential for spread.
Yes of course Don we need to be concerned especially in view of the increasing leggy situation like uh as we all know Singapore has had record cases of dengue but in my view it’s not really surprising that this is happening because you know any living organism faced with an onslaught to exterminate.
It will evolve genetically to escape the threat by introducing mutations in its DNA you know think of antibiotic resistance among bacteria and even those Escape variants of the covid-19 virus in the face of the onslaught of uh vaccines but yes we need to be concerned uh assuming of course that this resistance strains will spread more widely that of.
Course requires more research uh not surprised not surprising uh development as you put it and perhaps almost expected uh Professor pong but let’s look at uh the insecticide that the study involved the use of Permethrin a pyrethroid insecticide that targets the nervous system that’s what’s been in focus in this study uh these super.
Resistant mosquitoes evidently can survive it how far might the overuse of insecticide played a role here does it mean that we have to change the way that we sort of Target mosquitoes with different insecticides will they be effective even yes of course resistance can always be overcome by developing newer.
Insecticides but unfortunately the pipeline for developing this newer insecticides is fairly empty there are not many sort of coming along and of course I think the main issue here is you know why are these mosquitoes so strongly resistant and you know it’s sort of the factor really is that this new uh these mosquitoes can undergo.
Mutation which means they produce certain compounds which actually inactivate the insecticide so that it is uh basically turned into a harmless compound before it can get to the central nervous system of the mosquito and kill them it also these mosquitoes can reduce the capacity of the insecticide to actually penetrate the.
Outer skin the cuticle and interestingly some studies show that these mosquitoes can actually adapt and change their behavior so that they avoid being exposed to these insecticides so what does that mean then for a country like Singapore Professor pong anyone who lives here will know fogging is common and that pyrethrin it.
Permethrin it is the insecticide the synthetic form of it at least that’s what’s being used here in Singapore to control mosquito populations do we have to do things differently does it negate the need for fogging at all no I I don’t think it does uh don’t but I think let me Begin by saying that um many of these insecticide and.
Permethrin the agents cited in the study is highly toxic to both fresh water and as during aquatic organisms so it has potentially very serious uh environmental impact on biological ecosystems so having said that in addition to protecting the communities from mosquitoes which spread Dengue and other viruses such as zika and.
Chikungunya we need additional ways of controlling Dengue so what we need is a more integrated and holistic approach towards controlling uh Dengue now this for example I’m going to give you just seven ways additional ways there is the first option of non-insecticide mosquito control I think you have yourself interviewed or people.
About the world bakia project in Singapore the use of male infected infected with wall back here so that it reduces the mosquito population the eggs that are laid by the females do not hatch okay so that’s non-insect site control and it’s been fantastic thirty percent of hdbs have now been covered about 300 000 household they have seen.
Any EA reported at 98 reduction in mosquito populations in yishun Tampines I think and also in bukit batok towns and importantly when this mosquito wobakia program has been started for more than a year they have seen an 88 reduction in Dengue cases okay so that’s the first alternative way secondly obviously we need to continue.
Surveillance and early detection of the Dengue cases so that we can identify hot spots uh very quickly so that we can do quickly put in control measures thirdly public education and awareness that’s particularly important number four promote personal protection okay mosquitoes phrase even the old-fashioned use of mosquito nets all right fifth.
Very importantly we have to have the hospital capacity to manage the severe cases of dengue including considering some new treatments uh where there’s a lot of research going on actually in Singapore in in us for example uh the sixth and I think this is particularly important enforcement of Regulation and fines to reduce mosquito breeding sites.
You know Finding households that are breeding mosquitoes importantly implementing stop work orders at construction sites if they have been found to be breeding mosquitoes and as you know there are many many construction sites around Singapore especially after the relaxation of some.
Of the coffee restrictions and finally but not less important vaccines there are a couple of new vaccines coming along which are also going to help to protect the community there are certainly developments still to look at in this field Professor pong thank you very much for that uh Professor Tiki Pang there visiting professor at Young.
Lulin School of Medicine