Climate campaigners often worry that Malaria will spread due to increased temperature. So far, there’s little evidence of the effect of temperature, citing other factors. Plus there appears to be no linkage at all to temperature, but this new study suggests that even if it does, we might have a new tool that is far more effective at treatment.
Study identifies new way to kill the malaria parasite
Discovery could pave the way to new treatments for the disease
Scientists have discovered new ways in which the malaria parasite survives in the blood stream of its victims, a discovery that could pave the way to new treatments for the disease.
The researchers at the Medical Research Council’s (MRC) Toxicology Unit based at the University of Leicester and the London School of Hygiene & Tropical Medicine identified a key protein, called a protein kinase, that if targeted stops the disease. The study is published today (Tuesday) in Nature Communications.
Malaria is caused by a parasite that lives inside an infected mosquito and is transferred into the human through a bite. Once inside the body, parasites use a complex process to enter red blood cells and survive within them. By identifying one of the key proteins needed for the parasite to survive in the red blood cells, the team have prevented the protein from working, thus killing the parasite. The discovery could be the first step in developing a new drug to treat malaria.
The scientists – funded by the Medical Research Council (MRC) and the Wellcome Trust – used state-of-the-art methods to dissect the biochemical pathways involved in keeping the malaria parasite alive. This included an approach called chemical genetics where synthetic chemicals are used in combination with introducing genetic changes to the DNA of the parasite.
The researchers found that one protein kinase, (PfPKG) plays a central role in various pathways that allow the parasite to survive in the blood. Understanding the pathways the parasite uses means that future drugs could be precisely designed to kill the parasite but with limited toxicity, making them safe enough to be used by children and pregnant women.
Co-lead author of the study Professor Andrew Tobin from the MRC Toxicology Unit which is located at the University of Leicester, said: “This is a real breakthrough in our understanding of how malaria survives in the blood stream and invades red blood cells. We’ve revealed a process that allows this to happen and if it can be targeted by drugs we could see something that stops malaria in its tracks without causing toxic side-effects.”
Professor David Baker, co-lead author from the London School of Hygiene & Tropical Medicine, said: “It is a great advantage in drug discovery research if you know the identity of the molecular target of a particular drug and the consequences of blocking its function. It helps in designing the most effective combination treatments and also helps to avoid drug resistance which is a major problem in the control of malaria worldwide.”
According to the World Health Organization malaria currently infects more than 200 million people world wide and accounts for more than 500,000 deaths per year. Most deaths occur among children living in Africa where a child dies every minute of malaria and the disease accounts for approximately 20% of all childhood deaths.
Professor Patrick Maxwell, chair of the MRC’s Molecular and Cellular Medicine Board, said: “Tackling malaria is a global challenge, with the parasite continually working to find ways to survive our drug treatments. By combining a number of techniques to piece together how the malaria parasite survives, this study opens the door on potential new treatments that could find and exploit the disease’s weak spots but with limited side-effects for patients.”
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DDT has been used for malaria mosquito control in South Africa for many years. One problem is that after prolonged exposure, certain populations may become resistant. Many years ago when I worked in the field of medical entomology, there was a strange twist in the whole malaria mosquito control operation in the province now called KwaZulu-Natal. The huts of the rural folk were also infested with bed-bugs, and these had developed resistance to DDT. When the indoor surfaces of the huts were sprayed, the DDT killed the mosquitoes but merely irritated the bed-bugs, which apparently then attacked the occupants with a vengeance. As a result, the Health Department mosquito control teams became known as the ‘bringers of bugs’, and many householders locked their huts and disappeared over the hills when they heard the DDT guys were headed their way! Another unexpected consequence of all this was that the bed-bugs transmit serum hepatitis to humans, thus replacing one serious disease with another. Malaria epidemics in southern Africa are associated with periods of high rainfall, which happen on a cyclic basis. Mosquito populations then proliferate and spread beyond their normal distribution ranges. There is no reason to think that ‘climate change’ will increase the incidence of malaria in Africa, and this remains yet another fairy tale of the alarmists and journos. Thank you to Anthony for bringing us this interesting item – but it is a long way from the research laboratories in the UK to the remote rural areas of Africa.
I wonder what Obama’s legacy might have been had he thrown $500 million at Malaria instead of Solyndra.
Who would have thought that the most frequently inserted words used by scientists in the 21st century would be “if” , “could”, “might”, “possibly”, “may”. Isn’t progress wonderful.
This is an example of real science at work. No computer models of malaria spitting out results, but actual testing of the actual phenomena and collection of real data. Oh I am sure they did use computers and maybe even protien modelling software, but then they took the computer simulations and di real world experiments to validate the computers output.
http://www.theatlantic.com/technology/archive/2012/11/the-bat-tower-the-30-foot-monument-to-biological-pest-control-and-cross-species-design/265465/
There is not drug.
There is a possibility of a drug somewhere in the future. It currently takes, what? Approximately ten to fifteen years to get a drug through the FDA?
Another news release long before there is genuine news to release.
I’ve commented on this absurdity before. Many (possibly hundreds) of workers on the Erie Canal died of Malaria during the Little Ice Age (Canal construction began in 1817, in the period of intense cold that followed the Tambora eruption two years earlier). Malaria was endemic in Canada and Siberia. It is not limited by cold, then or now. It is confined to warm tropical countries now only because they are poor and failed to eradicate or control the Anopheles mosquito and treat/protect enough humans to break the chain of transmission. It is a simple fact that humans are the only animal reservoir for Malaria so if we prevented all human cases of Malaria for one single year Malaria would be eradicated from the Earth. Indeed, given the lifetime of mosquitoes it probably wouldn’t take a full year.
Here having a temperate climate and winter does help, but the key is not as it was then having houses with screens, adequate mosquito netting for beds, air conditioning so you can sleep indoors at night without open air circulation to remain cool enough not to die of heat exhaustion before morning, and adequate medical resources to treat malaria cases that emerge to eliminate the residual plasmodium and break the chain of infection. A vaccine would also (obviously) be sufficient to wipe it out in a matter of year.
All of this requires a) cheap energy; b) education; c) the development of wealth and social/economic standards in the third world. And we have the global wealth to easily accomplish this.
Sadly, what blocks this is not DDT or the lack thereof — I’m perfectly willing to believe that DDT is a bad thing to spray indiscriminately because very few chlorinated hydrocarbons are good things to spray indiscriminately. It is the diversion of the focussed will and surplus wealth of the world into “Global Warming” remediation instead of the elimination of poverty. It is the perpetuation of poverty caused by the artificially high costs of energy caused by this diversion. It is (and there is no easy way to say this, either) the nonsense of religions and regional tribalism that perpetuate strife and one way or another interferes with the education and social reform needed to break the chain of infection. Yes, in some places religious workers do good works and help, but when faced with e.g. ISIS or the damage caused by religious extremism, that work fades to nothing.
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Well it does help to remember that the only infectious disease that has been eradicated so far is smallpox, a disease which is transmitted directly from human to human, and that this was accomplished with an effective and cheap vaccine, under global political conditions that were more conducive to the effort than they would be today.
An effective malaria vaccine is still not on the horizon; in fact, there is no completely effective vaccine against germs other than viruses.* Moreover, both drugs directed at the malaria parasites and insecticides directed at the mosquito vectors are afflicted by resistance and therefore will not suffice to eradicate the disease.
DDT: The only large-scale attempt to use it outdoors against malaria was made, and failed, in Sardinia during the late 1940s. Since then, it has been used indoors, and the environmental and medical side effects of this application are marginal. (Agricultural use and abuse is a separate issue.). The problem with it is not that it is banned – for the ban concerns only agriculture; its use against malaria is regulated by the Stockholm convention – but widespread resistance, particularly in India, where DDT use has been ongoing for many decades.
I agree with you that the key to successful eradication of malaria (and other infectious diseases) will be economic prosperity and good administration.
*(Diphtheria and tetanus are bacterial diseases and are preventable by vaccines, but those vaccines inactive the exotoxins of the bacteria; they do not kill the bacterial cells themselves. Various vaccines directed against bacterial cells such as Hemophilus or meningococci are usefully but not completely effective.)
Risk vs Reward
DDT risk is known to be hyper inflated. Sea bird egg shell thinning… remember THAT lie!
Reward 500,000 lives per year saved, at least.
Therefore:
Risk = 0.0001
Reward = 10,000,000,000
So why isn’t the earth covered with 1 foot of DDT by now and why aren’t mosquitoes a forgotten boogyman story to scare kids?
It is unfortunate that the report here did not specify which malaria specie(s) were involved in the study. Of the four human species, one in particular, P. falciparum, is perhaps the worst. It causes changes in the “stickiness” of the erythrocytes it infects, leading to secondary damage in organs such as the brain and kidney, where the infected cells could be said to “clog” the capillaries, causing syndromes like cerebral malaria and “blackwater fever”, where the urine turns almost black. It would be a Godsend if this killer could be stopped cold in its tracks. Further, if the kinase mechanism is common to all, and characteristics the key enzyme sufficiently similar, all well and good.
However, as stunning as these findings identifying a key enzyme needed for survival of the erythrocyte form (the merozoite) are, developing a workable therapeutic is a different matter. Obviously it must be effective against all four species. Beyond that, it must be cheap and readily available to treat indigenous populations, who, as with any anti-malarial therapy, must be overseen for a sufficient duration of time to break the parasite’s local life cycle. Development of resistance to the treatment is additional matter, of course.
DDT on the other hand? Spray it, and forget it. It does its job without monitoring.
Cinnamon Oil Kills Mosquitoes
Date:
July 16, 2004
Source:
American Chemical Society
Summary:
Cinnamon oil shows promise as a great-smelling, environmentally friendly pesticide, with the ability to kill mosquito larvae more effectively than DEET, according to a new study.
This (in form) is not new.
http://www.newscientist.com/article/dn3179-herbicide-fights-malaria-in-people.html
From the discovery that the malaria genome is 1/3 plant, someone tested (on a small adult group) a herbicide tailored to target one of those genes, with immediate success (NS links to the original Lancet paper). I had expected a flurry of activity resulting in a suite of candidate malaricides targeting that gene or others, avoiding features likely to produce side-effects in mammals. Modern molecular modelling for such is well-established.
As far as I can tell, that initiative ended at that trial. Has anyone seen more on the topic?
I didn’t note this article in any of the posts, apologies if I missed it, but it seems relevant: http://wwwnc.cdc.gov/eid/article/6/1/00-0101_article From Shakespeare to Defoe: Malaria in England in the Little Ice Age.
For those unaware, Paul Reiter is a former head of CDC. He is also vilified as a climate skeptic because he dared to question the connection between global warming and malaria’s possible resurgence.
On the DDT side of thing…it’s not a cure-all. It’s a useful tool that may retain some utility for quite a while and it certainly could have saved any number of lives. Alternatives are needed, but the current perspective on what an insecticide should be (low toxicity, short residual, harmless breakdown products) and what is allowed to be registered doesn’t quite jive with what is achieved with DDT. The mammalian toxicity is relatively low (moderate by classic definition meaning an acute LD50 between 50 and 500) but the residual is what kick’s mosquito derriere. We don’t like residual effects (this is why we’re having bed bug issues too) anymore. So we’re unlikely to come up with alternatives of that sort. Affecting the vector in some way is likely the best hope going forward. But the ban on DDT in the third world heavily affected by malaria is/was borderline genocide.
On Fred’s suggestion of cinnamon oil – um, no. First, DEET is a repellant, not an insecticide, so it doesn’t kill anything. Even achieving the most minimal of control with cinnamon oil in terms of mortality would make it more effective than any repellant, DEET or otherwise. Second, 2004 study – we’re 11 years beyond that point; given we’re aren’t spraying cinnamon oil all over the planet I’m going to go out on a limb and suggest that once they got to efficacy trials it did diddly, much as it does as an insecticide in horticultural situations. Sadly the EPA requires no efficacy data for registration of insecticides, it lets the efficacy in the world decide the survival or failure of any given product. So cinnamon rears it’s head, mostly in the organically inclined world, every couple of years as a miracle insecticide. Lots of people buy it, someone makes money for a while and then people stop buying it because it doesn’t do squat. It goes away for a little while and the cycle repeats.
Boulder Skeptic
July 9, 2015 at 10:19 pm
“Your solution kills. Not a strawman dude…”
My solution?
Note please, that I’ve said not one word in this thread about that continent south of the Mediterranean Sea, about which you and many others have such great and noble concern, nor have I made any recommendations about the use of DDT.
https://en.wikipedia.org/wiki/Straw_man