Hi

Mosquito Sterilization Methodology:

The sterile insect technique is a method of biological control, whereby overwhelming numbers of sterile insects are released. The released insects are normally male as it is the female that causes the damage, usually by laying eggs in the crop, or, in the case of mosquitoes, taking blood from humans.

The sterile males compete with the wild males for female insects. If a female mates with a sterile male then it will have no offspring, thus reducing the next generation's population. Repeated release of insects can diminish small populations, though it could be impossible to eradicate it and is not efficient against dense insect populations.

Some articles related to sterile insect technique:

http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2946175/

https://www.ma.utexas.edu/users/davis/375/LECTURES/L10/sterile1.pdf

http://www.malaria.com/questions/sterilizing-mosquitoes

Kindly see the following:

1.  Dyck, V.A.; Hendrichs, J.; Robinson, A.S., eds. (2005). Sterile Insect Technique: Principles and Practice in Area-Wide Integrated Pest Management. Dordrecht, The Netherlands: Springer. ISBN 1-4020-4050-4.

2.  Vreysen , M. J. B. , Robinson , A. S. , and Hendrichs , J. ( 2007 ) . “ Area-wide Control of Insect Pests, From Research to Field Implementation . ” 789 pp. Springer , Dordrecht, The Netherlands.

Dear Sir,

Is it applicable to mosquito. 

I would like to use plant for this purpose.

with regards

K.Sahayaraj

The paper about malaria uses mosquito.

Kitherian Sahayaraj

do you to do this just in the lab or are you asking for the field application

in the lab studies normally chemical sterilizers are used however, for the field use radiological techniques are used successfully for the sterile insect control strategy.

as far as mosquitoes are concern I don't know any successful story.

if some one could give such reference,  it would be adding to my knowledge . 

Personally I am a little skeptical about sterilization in mosquitoes. During the late 80,s radiation was used to sterilize male mosquitoes in some countries (El Salvador is an example). Sterilized male mosquitoes were released in malaria endemic areas. However the sterilized males were less competent than the unsterilized ones to mate with the females, and the impact of the method was very low in the reduction of mosquito populations.

that is right dr.Eduardo Fernandez. this is I mentioned that successful mosquitoes eradication/management through   sterilization technique is not known at least to me

I plan to sterilize the mosquito with bioprincipals of seaweeds

However it is in initial stage proposal 

dear dr. Kitherian Sahayaraj  do you have some reports of your candidate plant species on this respect on other insects?  if not I must recommend you to study it with fruit flies it would facilitate you to compare the results and help you in forecasting the efficacy. if you have done this than before embarking on the sterility studies first study the persistence in the environment in which you are going to use this one.  

you know that sterile insect method had a successful story in fruit fly , for us in Sudan we had a promise project with IAEA in using this in eliminating malaria which is known to be endemic in my country I recently join the SIT team for this issue , we  have a notice story  in breeding the mosquitoes with large quantity in our lab , and we have limited field release until now but as implementation method I can say nothing for this moment .

if any one need information about mosquitoes mass rearing he can ask my help , and I will do my best.my Email is [email protected]

as far as the fruit flies are concerned it story of around 1/2 a century or more, there are less hazards associated with pest however, mosquitoes are dangerous you cant deal them in the way you posted the picture, an extra care is required to prevent the workers from the accidentally released insect's bit.

Dear Kitherian

Your project is an interesting concept, although I must add some words of caution.  Sterile male release can be extremely successful for species that are either low in population density, such as was the case with  screwworm control in the southern states of the USA, where sterile male release flooded the population so that it declined, or for horticultural pests such as tephritid fruit flies that can be attracted to a feeding bait station and thus pick up the chemosterilant from there.

For mosquitoes there are several practical issues that need to be addressed.  

First is the overall population of mosquitoes, which for many problem species is extremely large compared with the population of flies where the method has been successful - sometimes measured in millions per square kilometre rather than thousands.  Consequently, the release must also be measured in millions, or even tens of millions if the problem cited by Eduardo of the males being less competitive is a factor influencing success.

Second is that many anopheline vectors of malaria have widely distributed and often small breeding sites so you will need to release over a wide area in order not to miss any foci, and over a moderately long period of time.  If you are hoping to do this with Culex species you have an even harder job because their populations are often even less focused. 

Third is the fact that in conventional malaria control programmes it has been found in several places that suppression of a major vector species encourages or highlights the activity of a hitherto overlooked minor vector species, which means you need to have extremely good epidemiological data before you start otherwise you will run into opposition from sponsors, politicians, and especially the public who will not understand that the mosquitoes you are releasing are not going to cause a problem.

If, however, you are planning on attacking one species with clearly defined habitats and distribution over a small and restricted geographic zone you could be successful.  So I suggest you try this out on a species that fits these criteria first before embarking upon an ambitious project that will throw up many practical hurdles.  Best wishes for that and I hope it goes well.

Ian

Dear Ian F Burgess 

Thank you very much the elaborate and useful discussion for my clarifications. 

with regards,

K.Sahayaraj

Dear dr. Kitherian Sahayaraj are you thinking to employ any alternate control method simultaneously?

SIT/SMT is not almost sustainable specially with the mosquitoes there are lot of associated problems as well, if you have a low cost effective plant extract

• that could cause sterility at low doses when insects are exposed at larval stage

• has an ability to stay in the open environment longer

• and has no hazardous effects on non target

Then you should adopt to use this directly in the fields that control more mosquitos’ species at a low cost. You could get good achievement.

Dear Dr I saw nothing wrong in my pictures it represent the aquatic stages of anopheles from egg to pupa and according to my knowledge nothing risky with this stages and for the adults we have a special cages with protections tools and in case of fly emergence we have electric trap beside manual one , and away from ethical’s rules there is human exposed their bodies for  fly biting ( human bait), and even in science frequency exposure of biting may enhance our immunity towards getting disease and in my point of view I think it little bite is nothing if it help our community, and accidental hazards is facts in research unless it happened due to carless and I don’t think though about my team.

Dear Dr Ian

I respect your discussion because you say  facts about SIT implementation as control strategy of human disease , for that I say promise project because we began trials in mass rearing of anopheles arabiansis , the laboratory work goes better with developing facilities for mass rearing , we began our trial in semi isolated foci in Dongla so as to measure the efficacy of the SIT, and we hope to shift to wide area distribution for this , but as you mentions we  control and investigate other epidemiological and control methods parameters so as to judge about our result it globally known that its nit an easy task to use SIT for vector borne disease but as it work with tsetse fly ( although it has special habitat and behavior) it need to be investigated for mosquitoes. You can see my email if you want further information about SIT project  for malaria control please send me an email . but iam sure about one thing that we need your advice for better research work

Dear Tahani, Asalaam-u-aleikham

Thanks for your comments.  I am not sure how I can help with your research work but if you contact me directly ([email protected]) I shall see what I can do to help.

Dear Kitherian Sahayaraj,

It clearly depends on species. Sterile insects methods based on the irradiation are not suitable for all of the mosquito species. In fact, the applied doses should assure the full male sterility but also preserve their mating competitiveness. There are just a few species matching sufficiently these requirements. In addition, SIT framework should also require to perfectly separate males from females but contaminant females are always expected among released males if genetic sexing methods are not applied. Coreleased females can be vectors and, if perfect sterilization is not achieved, they could also transmit unpredictable mutations to the progeny. In addition, we also observed that irradiated females increase their stinging behaviour because the damage to the ovaries which compromise the egg productions also cause the failure of the mechanism which stop the stinging behaviour of the engorged females. To achieve the sterilization of certain mosquito species, I suggest you to read something about the use of the bacterium Wolbachia instead. There are a lot of projects already ongoing and base on the transinfection of this bacterium.