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Altruistic 'cure' for malaria - Comments

VrijVlinder's Avatar Comment 1 by VrijVlinder

What this suggests is that people become walking insecticides? I can see the logic but not the incentive if the insecticide does not also protect from the parasite the mosquito may carry.

Why not focus on sterilizing the mosquitos so they will not reproduce eventually dying off. All insects become immune to insecticides eventually and new ones must be created. If this experiment on living insecticides is to go forth I would prefer to start with cattle. How about treating the water where they breed?

I know people who got malaria. I do not think people are altruistic with their bodies past donating blood or other fluids. I think this project is only dealing with the delivery method (mosquito) and not with the parasites they carry. Not directly anyway.

If they can include a malaria vaccine along with the insecticide it would make more sense and people would be willing to become a human mosquito killer.

Mon, 07 May 2012 20:06:48 UTC | #940382

Alan4discussion's Avatar Comment 2 by Alan4discussion

Comment 1 by VrijVlinder

How about treating the water where they breed?

The problem with trying insecticides in the water is, that insecticides kill the fish and invertebrates which eat the mosquito larvae. Many mosquitoes breed in isolated or temporary pools where fish do not have access to eat them.

This is one of the problems of reckless mining creating such pools in abandoned workings in the Amazon.

Introducing fish can greatly reduce the mosquitoes in stable acquatic ecosystems, but there have been some very poor attempts at biological control, which have introduced the "Mosquitofish" pest, and made matters worse.

http://en.wikipedia.org/wiki/Mosquitofish_in_Australia -Many ichthyologists believe native species are more effective in population control than mosquitofish.[5] These include species such as the western minnow and pygmy perches.[6] Unfortunately, gambusia may have exacerbated the mosquito problem in many areas by outcompeting native invertebrate predators of mosquito larvae. Because of their aggressive nature and high birthrate, mosquitofish can overtake most native species in an area, drastically harming local populations.

Control of the pools and ponds where mosquitoes breed, and the introduction of sterile males, could help more than this "Altruistic Cure" which at best can only affect a few insects while risking human health. http://www.bbc.co.uk/news/science-environment-14422440 - Scientists have created spermless mosquitoes in an effort to curb the spread of malaria. - Experts say that this is an important first step toward releasing sterile males into the wild to reduce the size of mosquito populations.

Tue, 08 May 2012 18:07:35 UTC | #940583

GerhardW's Avatar Comment 3 by GerhardW

Useless, unless you can poison the blood of any Mammal (including all Humans), any Bird and many Repiles and Amphibians every 24 hours....

Tue, 08 May 2012 18:51:14 UTC | #940589

Peter Grant's Avatar Comment 4 by Peter Grant

So he's patenting an 'altruistic' cure?

Tue, 08 May 2012 21:14:02 UTC | #940614

Sinister Weasel's Avatar Comment 5 by Sinister Weasel

There are already projects where hundreds of millions of sterile mosquitos are released, so every other mosquito they mate with does not reproduce. The problem with the flea treatment ideas is the staggering cost it would involved for enough people to take the medicine every 24 hours, considering the wealth of the countries that suffer most heavily from malaria. Few people can afford a mosquito net or otherwise, so how would they afford this? Or a better question would be why would anyone fund this when cheaper alternatives exist?

Fri, 11 May 2012 10:34:56 UTC | #941004

Sjoerd Westenborg's Avatar Comment 6 by Sjoerd Westenborg

All valid points, and I agree it is not a perfect solution. Alan4Discussion already explained the downsides of poisoning a water source, and offered a viable alternative.

The downsides of vaccinations and mosquito-nets are that they are individual and temporary solutions. The upside of this medicine is it could wipe out the parasite and it's carrier in fairly isolated ecosystems such as islands and far away regions. Yes, mosquitoes prey on other mammals too, but killing off the mosquitoes that target humans is of course the most effective way of prevent humans to get bitten.

My question was rather whether this medicine, if proven to be effective, would still fail due to our rather ego-centric nature and short-term thinking.

Wed, 16 May 2012 11:26:44 UTC | #941808

VrijVlinder's Avatar Comment 7 by VrijVlinder

There has been interesting genetic studies about Plasmodium vivax aka malaria parasite. In southern Mexico. These are a bit dated but the results are what counts.Does circumsporozoite protein variation affect P. vivax survival in mosquitoes? It is a fact that every organism has or is susceptible to parasites. We are this planet's parasites, and have our own microscopic parasites and life size ones. It would seem that being that parasites affect the host adversely, they are unwanted and unnecessary. I consider the existence of parasitic life forms, proof that no one intelligent could have come up with such a cruel outcome . Cruel of course only to the host, the parasite likes the way things are and if it could think it would argue that's evolution folks!!

If that is evolution then we can alter the path for plasmodium to become extinct. In less time that it took to find a suitable long term host.

I think all parasites adapt to any evolutionary variant that may occur affecting it's host. If we can find a protein which makes them die or alter a specific process, a vaccine. Or with the use of genetic manipulation to express the desired results and cause the parasite to find a new host. It would eventually evolve to find another host or to invade humans again.Potentially.

In southern Mexico P. vivax malaria parasites carrying different circumsporozoite (CS) protein variants exhibit differences in development success in two local mosquitoes, An. albimanus and An. pseudopunctipennis [Gonzalez-Ceron et al., 1999; Rodriguez et al., 2000]. The geographical ranges of the two mosquitoes do not overlap extensively, with An. pseudopunctipennis found primarily at higher altitudes (above 600 m) [Manguin et al. 1995] and An. albimanus at altitudes < 100m [Rubio-Palis et al., 1997]. The two CS protein variants, termed VK210 and VK247, differ in the amino acid composition of the central repetitive region of the gene: ANGA(G/D)(N/D)QPG in VK247 and GDRA(D/A)GQPA in VK210 [Rosenberg et al., 1989; Kain et al., 1992]. In general, An. pseudopunctipennis is more susceptible to VK247 variants and An. albimanus is more susceptible to VK210 variants [Gonzalez-Ceron et al., 1999]. However, subsequent studies of the fate of parasites carrying the two CS variants revealed that the destruction of parasites in the incompatible mosquito occurs prior to the expression of CS, probably during the ookinete and/or early oocyst stages [Gonzalez-Ceron et al., 2006; 2001]. Further, in Columbia the opposite pattern was observed, with VK210 parasites more prevalent in An. pseudopunctipennis [Gonzalez et al., 2001].

Microsatellite typing of P. vivax in southern Mexico has revealed population structure and restricted gene flow in an area of less than 100 square kilometers [Joy et al. 2008]. Re-analysis of laboratory mosquito feeding experiments has confirmed that these populations differ in their ability to infect An. albimanus and An. pseudopunctipennis, suggesting that parasite population structure results from the adaptation of malaria parasites to their vectors.

Underlying genetic structure appears to have led to a spurious association between CS variants and mosquito infectivity. Therefore, despite the observed association between CS repeat variant and mosquito compatibility, it seems unlikely that CS is directly involved

Thu, 17 May 2012 22:41:26 UTC | #942108

Alan4discussion's Avatar Comment 8 by Alan4discussion

Comment 6 by Sjoerd Westenborg

The downsides of vaccinations and mosquito-nets are that they are individual and temporary solutions. The upside of this medicine is it could wipe out the parasite and it's carrier in fairly isolated ecosystems such as islands and far away regions. Yes, mosquitoes prey on other mammals too, but killing off the mosquitoes that target humans is of course the most effective way of prevent humans to get bitten.

I believe that some Scottish inventor discovered that their vicious midges would go for buffalo sweat in preference to humans, so set up some to attract them along with a vacuum cleaner and a bag to collect them. Very popular with golf courses and hotels! - http://richarddawkins.net/comments/530037

In terms of individual temporary solutions, a variation on these ones would seem to be much more effective than the the one in the OP !

http://www.midge-terminator.co.uk/RunScript.asp?page=78&article_id=14&ar=ar&nar=NewsArticleDetail.asp&ap=

...and/or the use of repellents:

Certain chemicals, found in greater amounts in extracts that cause low attractiveness to midges, elicit a repellent effect in laboratory assays and repellency trials in the field. Differences in the production of these natural human-derived compounds could help to explain differential “attractiveness” between different human hosts. - http://www.bioone.org/doi/abs/10.1603/033.046.0205

Sat, 19 May 2012 11:40:47 UTC | #942280

clodhopper's Avatar Comment 9 by clodhopper

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Tue, 22 May 2012 08:11:54 UTC | #942768

clodhopper's Avatar Comment 10 by clodhopper

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Tue, 22 May 2012 08:13:57 UTC | #942769

clodhopper's Avatar Comment 11 by clodhopper

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Tue, 22 May 2012 08:18:05 UTC | #942770