Mozzies facing aerial chemical attack

| 24/10/2011

(CNS): The Mosquito Research and Control Unit (MRCU) will be commencing a new low-level aerial operation this week in order to launch a full frontal attack on the pesky local mosquito as it comes towards the end of the insect’s season. The MRCU will be dispersing larvicidal Altosid pellets into stagnant water, the prime breeding sites for certain mosquitoes throughout Grand Cayman’s swamp areas. The pellets once wet will release a chemical for several months at a time which will kill mosquito larvae emerging from hatched eggs. Government officials said the larvicide is EPA approved and doesn’t present a threat to humans, pets or wildlife.

The MRCU’s custom designed Ayers Turbo Thrush aircraft, fitted with precise equipment and on-board navigational system will provide accurate placement of the pellets into the swamps

“This type of application provides long-term control,” the MRCU unit stated. “The amount of mosquitoes hatching will be significantly reduced which means there will be fewer mosquitoes to lay eggs back into the swamp, reducing the subsequent number of eggs in those areas. This type of control not only lessens the nuisance of biting mosquitoes, but also reduces the need for adulticiding spray chemicals to be applied later.”

The daytime campaign in Grand Cayman should be completed within a couple of weeks and officials stated that the  operation will then shift to Cayman Brac and Little Cayman where a similar campaign last year proved highly successful.

MRCU scientists will monitor the application’s effectiveness on the ground throughout the operations.

For further information or enquiries please contact the MRCU Main Office on 949-2557.


Print Friendly, PDF & Email

Category: Science and Nature

About the Author ()

Comments (25)

Trackback URL | Comments RSS Feed

  1. Anonymous says:

    Why isn't DOE concerned about the use of insecticides in our beloved swamps. Doesn't this then leach into our ground water and get into our food chain?

    To be a mosquito er fly on the wall at the dinner table…

    • Anonymous says:

      Did you actually ask DoE this question and they replied "DoE is not concerned", or did you just go ahead and write your post?

  2. Anonymous says:


    Most of the Caymanians that worked with MRCU in the 'old days' had also worked previously for many years in the engine rooms of merchant ships. There is a likelihood that lung cancers could have developed from prolonged exposure to asbestos at that time.

    There is talk that Cayman has an 'unusually' high rate of cancer. Perhaps not true. Cayman's cancer rate is in line with most of the rest of the Caribbean which, as a whole, is slightly higher than the rest of North America. The types of cancer that are at the top of the list are digestive cancers and breast cancers. Cayman also has a 'snow bird' and retired expatriate population who come and go but will also enter the island's health statistics.

    The Caribbean has a notoriously bad diet ……. full of starch and fatty foods which might be akin to high rates of diabetes and digestive cancers in the region. A pattie and soda for breakfast, oxtail plus rice n beans for lunch etc etc …There are also plenty of cancer-forming agents out there on the island that have hidden potential …. how about diesel and car emissions? ……. how about leachate from the landfill? How about solvents and oils that are not used and/or disposed of correctly? I would imagine that someone with a domestic aerosol (roach killer) is far less regulated than an MRCU application. How many times have you followed a roach and emptied a quarter of a can?!

    I MRCU's defence they apply chemicals in a very precise manner. Adulticides and larvicides are applied according to labels regulated by the EPA studies for chemical registration. The applications equipment controls droplet size and drift of adulticides ensuring minimal dosage rates are applied to target the flying mosquito (not humans). Most of those formulations are now water-based and have very low persistence in the environment. The solid (pelletized) larvicides spoken of in this news article target the mosquitoes in the swamps and release chemicals specific to controlling the mosquito. One of the main larvicides used releases a 'hormone analog' which substitues for the mosquitoes' developmental hormone thus preventing progression of the larvae into the adult phase. We do not posess this hormone or  biochemistry and thus this approach is ineffectual towards us.

    Toxicity is a function of dose and exposure. If you absorb or are exposed to anything (including sugar, coffee and even patties) at an ill-advised dosage and for a long period of time then that substance has the potential to be toxic. You might also be surprised at the high volume or weight of mosquito specific pesticides that need to be ingested to have a lethal or long term oncological effect when compared to various everyday products utilised or consumed by the public.

    My point being ……let MRCU do their job. They have scientists who don't intend to harm the environment and will contribute to improving technologies and….. good applicators who are trained and know what they are doing. If you decide that MRCU is not necessarily doing a good job and is causing cancer then feel free to make some suggestions as to 1) how to control nuisance biting and 2) how to control diseases such as malaria and dengue on the island. Cayman is unique in its proactive approach in the Caribbean.This ensures the health of the public and  maintains the formula wherby tourists will keep coming here to spend money. Cayman is one of the only Caribbean islands that does not have high rates of dengue at present.

    Interestingly I know several 'old school' folk on the island who suggest that 'diesel into the swamp' will get rid of mosquitoes the good ole fashioned way! I would rather take my chances and have too many patties in the morning ………..

  3. Whodatis says:

    Considering that the origin of the most deadly disease facing the world today (HIV / AIDS) was during the process of a "harmless" scientific experiment in the Belgian Congo (1957-1960), I think there should have been much more disclosure of this program beforehand.


    Do the research, ignore the politically / regionally / racially  perversed "official findings" for a moment – then examine the facts surrounding the regions of the earliest discovered cases of HIV / AIDS – then compare that information to the "official" explanation for said initial cases … and finally share with us your thoughts.

    Some may consider the above as irrelevant however I find the fundamentals of both situations to be quite similar in nature.

    Furthermore, we have seen how catastrophic the outcome can be if "science" gets it wrong. (Add to that the good ol' modern day international politics and we are left with a globe-sweeping disease killing people by the millions annually that is allegedly mysterious in origin.)

    How does that relate to us in the Cayman Islands?

    Had the world / Cayman been better informed as to ALL potential theories of the origin of HIV / AIDS I am quite certain that there would have been far greater hurdles to overcome locally.

    Who could argue against that?

    • Anonymous says:

      Now I know for sure you're nuts..

      • Whodatis says:

        Sorry, you are going to have to elaborate on that point – otherwise you will be rightly dismissed as a typical lemming.

        I await your reply.

        (Yeah … start Googling.)

        • Anonymous says:

          Easy to do. You apparently believe that white men in Belgium caused AIDS. Do you wear a tin-foil hat?

          • Whodatis says:

            Your choice of words and area of focus clearly demonstrates to me that I ought not to engage in further discussion with you.

            Thanks for replying though.

          • Anonymous says:

            A lot of things was caused by same, but people today profited from these things so no one wants to admit it, the truth will come out someday, may god help you, but you may not want to accept that because he would tell you that raceism is wrong.

        • Dirk says:

          Not the original replier, but AIDS is not "the most deadly disease facing the world today". By number of deaths annually that would be heart disease. Then cancer. Then cerebrovascular disease. Then lower respiratory infections. Then HIV/AIDS. <a href="">Yes, Google is our friend</a>.

          I assume you are in general referring to the <a href="">OPV AIDS hypothesis</a> (no lectures on Wikipedia as a source, please, it is an easy and comprehensive overview which links to many peer-reviewed scientific journals), which theorises that HIV was transmitted to humans 1957 – 1960 through the oral polio vaccine that had been developed in chimpanzee tissues contaminated with SIV (the simian version of the disease which mutated into HIV through zoonosis). Those who push this theory believe that an extensive experimental vaccination programme in the Belgian territories (now DRC but also Rwanda and Burundi) using a different type of polio vaccine than that used throughout the US introduced the virus into the human population there.

          This theory, and especially the fringe group that takes it farther to believe that colonialists were intentionally propagating biological warfare, has been refuted. HIV was present in human populations for well over a decade before that "experiment" happened, potentially as early as 1915 but most certainly by 1941. Additionally, the vaccine was made from monkey tissue, not chimpanzee tissue; there are phylogenetic differences between SIVin that region and all types of HIV; and tests of the remaining stocks of the vaccine found no evidence of SIV or HIV contamination. Any reputable scientist will tell you bushmeat practices most likely gave rise to HIV. There is no systematic coverup by the colonialists and neo-colonialists. By the way, that was based on me considering "the facts" as you suggested.

          Beyond that, I've read your post multiple times and to be honest I'm still not exactly sure where your conspiracy theory is going this time. Are you being deliberately cryptic or is the whole thing just not that well thought out? Or did you just want to ruminate on how the man loves to lie to us and decided this was close enough to start yapping about OPV and AIDS? You seem to be insinuating that people have lied and continue to lie about the origins of HIV and that, as you believe "the fundamentals of [MRCU activities and the OPV administration] to be quite similar in nature", it is possible that there may be a similarly "catastrophic" outcome in the case of local attempts to control mosquitoes as well. I am seriously hoping you do not mean the development of a mutateddeadly virus that will spread across the globe and kill millions anually, so I will assume you simply mean unintended and terrible consequences, potentially on a global scale and which could include the development of a mutated deadly virus that will kill millions annually.

          Firstly, science in the 1950s was light years behind science today and considering the strict regulations and developments in methods to control pests we should all trust the MRCU has thought this one through. Anonymous at Tue, 10/25/2011 – 15:30 has written a very enlightening comment that includes further information on this current approach, which I for one very much appreciate. The MRCU could probably improve how their work is perceived in the community if they did some PR (sorry, "disclosure"). However, there would still be loonies like you, Whodatis, so sometimes just doing your work well and not sweating the conspiracy theorists is best.

          • Whodatis says:

            Ok, that was quite a meaty post there – I see someone did their homework, albeit sloppily.

            Couple of things…

            1. Nowhere in my post did I suggest an intentional act on the part of the scientists. (However, that is not to say it was not possible – regardless such an act would only ever be proven by way of confession.)

            2. Re: "Additionally, the vaccine was made from monkey tissue, not chimpanzee tissue" – This has not been proven. The investigation that led to this conclusion was in no way exhaustive. (The scientists at the core of the scandal were the ones making this claim.) Furthermore, eyewitness accounts of the actual staff members contradict that finding altogether.

            3. Re: "Any reputable scientist will tell you bushmeat practices most likely gave rise to HIV."

             – Africans were indulging in "bushmeat practices" for literally THOUSANDS of years prior to these experiments. However, we are still meant to ignore the evidence of the first instances of HIV being traced within the same area within ONE YEAR after the fact?

            4. The primary objective of my post was to highlight the issue that this mosquito experiment was frankly forced upon the people of the Cayman Islands, which is something that I am completely against – regardless of the jurisdiction. (I raised the HIV / AIDS as a colorful example. Otherwise we wouldn't be having this wonderful debate right now, would we?)


            Are you comfortable that you have been properly educated to the issues surrounding this theory?

            Do you outrightly reject this theory?

            Do you believe that the enitre scientific community has outrightly rejected this theory?

            What in your opinion accounted for the sudden and concentrated outbreak of HIV / AIDS within the same region?

            Do you believe that such an outbreak in that very region would have occured had the experiments not been carried out?

            Are you wiling to disregard the timing of the outbreak in the region, the eyewitness accounts of the workers, the biased investigations and debates within the UK / USA, the inconclusive "conclusive" evidence of the offical reports etc. – and thereafter accept the explanation of the very people who stand to lose their credibility and reputation if the mountain of circumstantial evidence proves otherwise?

            Lastly, and you can ignore all previous questions and only respond to this one if you like; What do you believe is the origin of HIV / AIDS?

            • Dirk says:

              1. I distinguished between AIDS OPV believers and the extreme fringe group of AIDS OPV believers. You did not clarify to which group you belonged in your original post; thank you for doing so now.

              2. Yes it was. In 2000 at a meeting of the Royal Society THREE INDEPENDENT LABS released results of tests which proved the vaccine was made from monkey kidney and there was no evidence of HIV or SIV infection.

              3. A lot was happening in equitorial Africa during this time period that could have promoted zoonosis and widespread infection. Rapid urbanisation and colonialism brought many social and medical changes, including increased migration, population concentration, labour camps, numerous other colonial abuses, new medical practices (including antibiotics introduced ~1950), widespread and mostly unsafe injection campaigns (to be clear, as OPV is an oral vaccination it should not be considered here), promiscuity, prostitution, more guns = more bushmeat, more people to feed = more bushmeat, etc, etc. Many of these factors would also stress the population, and stress makes people more susceptible to infections (particularly acute ones). Additionally, rapid spread of a disease – particularly a zoonotic one – increases its ability to biologically adapt to the host and take hold in a population.

              4. How do you propose the MRCU (or any Government agency) realistically carry out its work without "[forcing] it upon the people of the Cayman Islands"? I'm believe in consensus, engagement and meaningful public participation in democracy. But at some point the details must be left to those we elect and hire for practical reasons and efficiency.


              – Yes. One could say I dabble in science.

              – Yes. I think it required investigation when it was first proposed and (despite initial hesitation because of the potential impact if it was correct) I believe the scientists have adequately investigated and refuted it.

              – "Entire scientific community" is not something that anyone can actually speak to and it's not something that really matters. There are still some in the "scientific community" that reject evolution and/or climate change. The vast majority of the scientific community is good enough for me.

              – See #3 above.

              – If you refer to only the OPV campaign as "the experiment" then yes. If you include all injection campaigns then I am not sure.

              – Yes, because a) correlation does not equal causation, b) eyewitness accounts have been refuted by other eyewitness accounts and also by science, c) just because the UK/USA are biased does not mean this conclusion is wrong, d) "conclusive" evidence is a big standard of proof to demand; we don't have that for evolution, dark matter, and many other commonly accepted theories, particularly in experimental physics. Occam's Razor, my friend, the OPV AIDS theory didn't hold up. I'm fine with what we currently have, which is consensus on the most likely explanation and consensus on one that is almost certainly not the case, e) yes, just because people have much to gain (or conversely much to not lose) from being right doesn't mean there is an elaborate conspiracy to prove themselves right when they are in fact wrong.

              – Bushmeat practices and zoonosis. However, I think what is more important is how it spread, and I believe changes brought by rapid urbanisation and colonialism nursed a pandemic (see also #3 above).


              A couple of questions for you:

              1. Coincidence of timing seems to be the biggest reason for you to infer causation. How do you explain the development of HIV-2 strains in western Africa (completely unrelated to HIV-1 that originated in the Congo) at the same time?

              2. Do you believe HIV only developed after 1957? How do you explain the scientific consensus that SIV developed into HIV in the late 19th or early 20th century, almost certainly by 1941? Koprowski's vaccine was first administered in 1950 and the batches made from African simian tissue years later.

            • Dan (not the ex-AG) says:

              I ran upon this "debate" and decided to weigh in. I know, three's a crowd, but I can't help myself. I'm going to respond to the questions you posted at the end of your post in particular.

              Are you comfortable that you have been properly educated to the issues surrounding this theory?

              Yes, and evidently moreso than yourself. At least within the realm of rational thought.

              Do you outrightly reject this theory?

              Yes. It's beyond the point of probable, and is furthermore based on false premises. In particular the specific occurance of a biological process that in this particular interest has no evidentiary backing as well as a complete misunderstanding of the principles of correlation and causation. Also, the timeline the theory relies upon is wrong.

              Do you believe that the enitre scientific community has outrightly rejected this theory?

              I think, like any segment of the population, that there are always fringe beliefs. In particular, there are members of the entire scientific community who do not subscribe to the theory of evolution, to the general ideas behind the origin of the current universe, or that human actions have caused an alteration in the Earth's atmosphere such that it affects climatic conditions. Despite a lack of total consensus (if only scientists could also be Quakers, eh?), such fringe beliefs do not actually add weight to fallacious arguments,even if a minority of proponents hold degrees in the natural sciences.

              Also, the common and most proper usage would be "outright."

              What in your opinion accounted for thesudden and concentrated outbreak of HIV / AIDS within the same region?

              Simply, infrastructural developments. Less simply, colonisation and a trend towards concentrations of urban populations, ease of transportation amongst widespread populations in a previously tribal and rural area and the actual documentation of HIV/AIDS made possible by the influx of Western medical practitioners in conjunction with above changes. It's like the whole tree falling in a forest with nobody around – HIV/AIDS certainly existed prior to the "outburst." However, it was unable to become widespread in any sense due to the lack of common mobility within infected communities. In a sense, any occurances of the virus would largely be self-quarantined. That barrier was removed in a micro-sense with the changes wrought by colonisation, and in a macro-sense by the improvement to rapid travel over long distances (access and cost of commercial flights, in particular).

              Do you believe that such an outbreak in that very region would have occured had the experiments not been carried out?

              Yes, because the experiments had nothing to do with the outbreak. Also, the outbreak had already been occuring, it just wasn't facilitated in reaching more geographically concentrated populations and therefore would have been harder to detect.


              Are you wiling to disregard the timing of the outbreak in the region, the eyewitness accounts of the workers, the biased investigations and debates within the UK / USA, the inconclusive "conclusive" evidence of the offical reports etc. – and thereafter accept the explanation of the very people who stand to lose their credibility and reputation if the mountain of circumstantial evidence proves otherwise?

              It's funny the way you frame your questions in order to try and add legitimacy to your arguments. You attempt to make it sound as if your premises are fact rather misguided opinion. Along the same lines, one could pose the question to you:

              Are you willing to disregard the dearth of evidence regarding the process through which OPV could induce the exact changes in SIV in order to make it communicable to humans? Further along that line, you would have to then assume that it was ONLY through this process by which HIV was mutated from SIV and therefore preclude all other possible explanations. Are you also willing to discount any other studies that have indicated the existence of HIV well before your catalystic moment?

              In regards to your circumstantial evidence (in which the circumstances are already beyond the point of tenuous), I believe the term you wanted was molehill, not mountain.

              Lastly, and you can ignore all previous questions and only respond to this one if you like; What do you believe is the origin of HIV / AIDS?

              I would have to go with a retrovirus that utilises the ability to target human cells responsible for the detection of foreign and "malicious" agents in the body in order to safely and effectively propagate inside a host. Unfortunately, the origin of viruses in general remains a rather murky topic, particularly as ultimate timelines are concerned. In fact, the whole subject of viruses is contentious, as the scientific community even has trouble defining whether viruses can be classified as living or not. I wouldn't really know where to start in defining any virus's origin. That being said, in regards to HIV, it was 100% before the OPV experiments, as tracing the evolutionary changes in the modern form of HIV indicate that at a minimum it was communicable and expressed in the very early 1900's.

              I will even go a step further and posit that it has existed for hundreds (note that would imply prior to the 1900's) ofyears but given the nature of societal organisation and migration in that region was undocumented and contained. Keep in mind as well that it's not AIDS that kills people, it's opportunistic ailments. Prior torecognising markers for HIV, people in that region would simply be dying of the very same diseases that had always killed people in that region (and been mostly indistinguishable given the lack of modern medical practices at the time). The biggest reason HIV was recognised first in the Western world was that normal illnesses, which the majority of the population had become immune to, or been very capable of fighting off without medical aid, were killing individuals. Without the ability to fight such common illnesses, or the widespread knowledge regarding the commonality of said illnesses, how would an "outburst" of HIV ever be defined to a specific time period without a particularly trained group of individual on hand to document it?

              My last question is just a bit of a personal attack on your credibility out of sheer spite for the outlandishness of your opinions on HIV/AIDS – do you think somehow the introduction of HIV to the US community by Gaeten Dugas was a conspiracy by Quebec seperatists in order to destabilise their southern neighbors in the hopes that the US wouldn't get involved if Canada were to have had a civil war? (In case you were unfamiliar, Mr. Dugas, a Quebecois airline steward, had been traced by epidemiologists as Patient 0 for the first expressions of HIV within the US borders.)

            • Whodatis says:

              @ Dan and Dirk,


              Excuse my language but the CNS automatic refresher just did away with my entire post!

              Anyway, I was essentially thanking both of you for your replies and saying that at the end of the day we are all forwarding and hanging on to personal opinions on the matter.

              Nothing has been proven or disproven, and some issues have been suspiciously injected (in my opinion). I am not one of those individuals that trust or respect all "official" findings forwarded by institutions. There have been many instances of interference of the actual scientific findings throughout history all in the name of geo-political efforts. As difficult or outlandish a claim that is for some people it is simply a fact.

              Thanks to both of you again – it has been interesting to say the least.


               – Whodatis

              • Dirk says:

                Right back atcha. I have a lot more respect for people who have knowledge and reasoning to back up their opinions, even if I disagree with the conclusion.

          • Anonymous says:

            Who do you work for ? .


  4. Anonymous says:

    It's about time! After we've been eaten alive for most of the rainy season already! I was wondering WTH was going on with MRCU – thought maybe their budget had been diverted to more important things like the Nation Building Fund or the Premier's travel expenses….

  5. Simple days says:

    I had an uncle who worked for MRCU and drove the Mosquito truck many moons ago. He died of lung cancer…. in the time that i knew my uncle and saw him he never smoked one day. But he work with the chemicals used to spray mosquitos…

    Cancer is unusually high in cayman and i have always wondered why… it could be due to outdated practice in the types of chemical used. 

    • Anonymous says:

      Hey, just about every former MRCU employee has died of cancer.  Look it up.

  6. Anonymous says:

    Isn't this a good reason to fill in the swamp or add a new development.

  7. Anonymous says:

    Many people believe that the high rate of Cancer in Cayman is due to the mosquito plane/truck spraying sporadically around the island.  What I have read above is that the pellets will release a chemical for months at a time.  I have translated that to mean that exposure to the suspected cancer cause went from sporadic exposure to contact exposure.


    I am not conviced that long term studies have been conducted on any of these chemicals to rule out whether the long term exposure can contribute to or cause the mutation ofcells developing into cancer cells. 

    • Cowitch says:

      What "many people believe" does not have any influence on the facts. Many people used to believe that the sun orbited the earth. Your "translation" seems to ignore that the chemical will be slowly released into stagnant water where it seems unlikely to be ingested by humans, rather than airborne.

      • Anonymous says:

        I assume you don't let your children play outside…

        • Anonymous says:

          Glad to hear that they are back out  only one problem the people that live in Smith Road Villas dont get any spraying the mosquito is killing us    so please remember us MRCU

    • Anonymous says:

      contact exposure is meant to say constant exposure