Skip to comments.DDT makes a comeback in effort to halt malaria
Posted on 08/27/2006 6:44:50 AM PDT by mathprof
Men in blue coveralls and white surgical masks began their annual trek into the countryside here last week. Methodically, they sprayed one home after another with a chemical most Americans probably thought disappeared from use long ago: DDT.
As villagers looked on, the workers doused inside and outside walls with a fine mist. It is a yearly effort to repel and kill mosquitoes that carry malaria - a disease that kills more than a million people a year, mostly children in sub-Saharan Africa.
Advertisement This small kingdom near South Africa is one of a handful of countries still using the pesticide, banned in the United States in 1972 because of its toxic effect on eagles and other wildlife.
But now DDT is poised for expansion in the developing world.
The influential World Health Organization plans to promote DDT as a cheap and effective tool against malaria. And the U.S. government has boosted its budget for malarial insecticide spraying in Africa twenty-fold, to $20 million next year.
The new push for household spraying reflects a growing belief in some quarters that significant progress on malaria will require a third major front, alongside insecticide-treated bed nets and novel anti-malarial drugs.
No one proposes a return to the widespread agricultural use that severely harmed ecosystems in the United States and Europe decades ago. The results of such spraying were famously depicted in Rachel Carson's landmark 1962 book Silent Spring, which launched the modern environmental movement.
Advocates of household spraying say the comparatively minute amounts used in homes pose no known dangers. Any potential risk, they say, is far outweighed by DDT's potency against malaria, as was seen in the late 1940s and '50s when it helped eradicate the disease in the United States and other industrialized nations.
But environmental groups...
(Excerpt) Read more at baltimoresun.com ...
I have a set of short biographical readings in my classroom. Each is about 3 paragraphs long. One of the books had a section on Rachel Carson--I ripped it out and threw it away.
You are correct about that!
I've heard for years that constant exposure of a species to toxic chemicals will over time give advantage to a mutant strain that is resistant. I tend to believe this is probably true with respect to DDT since some species, namely us, aren't affected by the stuff.
So, I think regulated use that guards against reistance and environmental damge as opposed to the outright ban in place since 1972 would be a common sense approach to the issue.
Not in Iraq. We bought some insect killer because there was a wasps' nest somewhere behind the walls of our office and the huge things kept coming in and flying around. When we read the ingredients, we saw that it's 70% DDT.
Kills the heck out of those wasps.
And none of us have grown third arms or anything like that.
Well, not yet. ;-)
No, she just twisted 'facts' until they fit her personal agenda.
Just like certain FReepers tend to do.
Just waiting for the day. The way we build and protect wetlands here, it's only a matter of time before we can enjoy the same.
DDT isn't a chemical like bleach, which nothing can survive in. If it's in low enough concentrations, some of the targets will survive, and they will be the ones who can survive low concentrations. Then their children will mostly be able to survive that low concentration, and some of the children will even be able to survive stronger concentrations. It's exactly like antibiotic-resistant bacteria. You build up a tolerance in subsequent generations every time you don't wipe out an entire "crop".
Most of the findings these whack jobs came out with is bull.
They've caused more deaths in Africa than every KKK member would have if they'd taken a gun to all of Africa....
the libs are such phony baloney pseudo-intellectuals.
Malaria had practically disappeared from the U.S. well before DDT came into use; nobody seems to know why, and nobody can promise it won't come back.
As a child I lived in Norman, Oklahoma 1951-1955. A DDT fogger on the back of a jeep fogged all the streets on a weekly basis. We children used to run after the jeep within the DDT fog that it was being dispensed. We would follow it for blocks. A fogger of DDT was used at drive-in movie theaters, they fogged every row. I'm 61 now.
One of my very first chores was "painting" screens with DDT every spring.
It was not the CDC but the Dept of Agriculture that banned the use of DDT in spite of no evidence that it was harmful. It was a purile, deceitful and cowardly political action by a Dept Director who was more concerned about angry Marxists than the health of the food supply.
Mosquitoes will develop a resistance to DDT at the same time humans develop resistance to Malaria. That is, it will take a long time. In the meantime you can save a lot of lives.
I assume it's the bacteria that lives in the digestive system of mosquitoes that is transferred from the host to a human's bloodstream when the mosquito bites them. People don't get diseases from the mosquito per se, but from bacteria and virus pathogens that are transferred from some other creature when the mosquito first feasts on it then goes and bites a human afterwords.
Scattered considerations in the Malaria and DDT issue:
1. William Ruckelshaus became the United States Environmental Protection Agencys first Administrator when the agency was formed in December 1970 when appointed by President Richard Nixon. During his tenure he oversaw a three-month hearing on DDT, after which he simply ignored the recommendations of scientists (and the draft ruling by the Administrative law Judge) and instituted a politically-inspired DDT ban. http://en.wikipedia.org/wiki/William_Ruckelshaus. I believe he was also a founding member of one of the major latter day environmental organizations during the 1960s as well, perhaps, the Environmental Defense Fund (EDF).
2. There several forms of malaria and only the form found in Africa south of the Sahara is typically quite deadly. Those found in South America and SE Asia are more the classic periodic severe fever types. By the early 1960s most all malaria in, at least, southern Africa had been eliminated through use of DDT. Thanks to the EPA ruling use of DDT essentially ceased in Africa with severe resurgence of malaria including the most fatal type which has now been killing 1-2 million people, mostly children, per year. In other words, while you read this piece they are dying at 2-4 per minute.
3. It would be nice to see how long DDT worked before the mosquitoes became immune to it. We do know that the first preventive treatment, chloroquine is now almost totally ineffective, the 2nd treatment Lariam (brand name) that began to be used in the late 1980s is now ineffectual in many areas of the world, (e.g., western suburbs of Phnom Penh) and the most recent drug, Malerone, is now the drug of chose for those that do not want an extended prophylactic treatment regime with doxycycline. Of course, all these options only apply to international travelers, as all but the richest citizens of the third world are much too poor to use them.
4. There may or may not be more brown pelicans now than there would have been sans a DDT ban. Independent variations in the anchovy populations confuse the data. It does appear that DDT tended to thin eggshells in heavy accumulations. The thinning of the shells has been shown to enhance raptor reproduction as some that would die before of failure to peck through the shell can now escape their egg shell tombs.
5. To me the conclusions seem clear and tragic: many millions of humans in the third world were avoidably killed while thanks to West Nile virus and no DDT even more millions of avoidable bird deaths also occurred.
Why does no one hold people who make such bad decisions up to the light of public ostracism?
"What is mosquito bacteria?"
Humm. In this case a proofreading error.
Should read mosquito larvae
"No one proposes a return to the widespread agricultural use that (ALLEGEDLY)severely harmed ecosystems in the United States and Europe decades ago".
Seems to me that DDT's nefarious reputation was never actually proven in any unbiased study.
Wasn't DDT one of those things it's defender ate without ill affect?
Thank you for clarifying the source of the DDT ban. My memory failed me.
I lived in Appalachia during the 50's. DDT was considered a miracle drug by rural people. It saved the lives of countless poor people. Banning it created serious conflict between people living on the land and people who wanted to control the way folks live on the land.
There was a popular song played on all the local radio stations entitled, "Ain't no flies on Jesus, 'cause He's sprayed with DDT."
It can not be stated strongly enough that the EPA from its beginnings has been and remains an enemy of people who depend on living on the land. The only law more grievous is the Endangered Species Act. Both are the result of a mentality expressed by the woman mentioned at the beginning of this thread who believes that all humans should be eradicated. That is the true agenda of these dispicable laws.
Pelicans are around here in the Gulf Coast of Mississippi big time (post ban). But I don't understand why the rest of the coastal birds survived. This is something I gotta look into, I'm not a enviro whacko, but this brings alot of new questions to my mind.
Does the DDT kill the malaria in the blood of the mosquito or does it kill the mosquito?
That, my friend is the key to these arguments. These idiots will sacrifice thousands of lives,(the elderly and young hardest hit) in the name of environmentalism, and act like they are doing us all a favor.
Read a book by PJ O'Rourke called All the Trouble in the World. He covers this type of thinking perfectly.
Thanks for the post. I assume the microbe isn't a "mongoose" and has the EPA stamp of approval. Along with DDT, it makes a fine weapon in the arsenal against arthropod pests.
I don't think it's a coincidence that Rachel Carson's promotion of the killing of 50 or more million people by outlawing DDT dovetails with the coming of age of the Hippies and the Leftie navel gazers during the '60's.
Rachel killed more people than Mao or Stalin or Pol Pot, perhaps not as many as Ghengis Khan.
'But environmental groups...
Had an interesting conversation with an extreme radical environmentalist the other day at a restaurant.
She said, and I quote, "wouldn't the world be a much better place if the human race was extinct"?
I asked if she was jesting. Turned out she was completely serious.
She followed up with, and again I quote, "It would be no great loss to me if all the humans in the world died tomorrow".
That is so irrational, even attempting to argue an apposing position is futile at best.'
I understand just exactly the kind of person you're describing. I think a good retort would have been - "well, show your leadership."
"The problem with DDT is that it kills pretty much every insect with which it comes in contact, good, bad, indifferent, it just kills them."
If it kills every insect, would that include Jimmah Cahtah?
"It's smart to use nature against nature.
Yes, the mongoose was introduced to Hawaii and the folks there just love them."
Kudzu - another example.
'I'm no infectious disease specialist
Well, I'm board-certified,and I assure you that DDT is essential to combat malaria.
It will also eliminate West Nile, EEE, and a variety of other undesireables.
Timely, pertinent and excellent post. Thank you! FR is blessed to have people like you among its readership and contributors.
I just finished the excellent book by David McCullough...." Path Between the Seas", about the building of the Panama Canal. We got rid of the malaria there by other ingenious means. No DDT was used, as it wasn't yet invented.
They simply, by hard work, got rid of the mosquitos.
"Mosquito resistance against DDT
In some areas DDT has lost much of its effectiveness, especially in areas such as India where outdoor transmission is the predominant form. According to V.P. Sharma, "The declining effectiveness of DDT is a result of several factors which frequently operate in tandem. The first and the most important factor is vector resistance to DDT. All populations of the main vector, An. culicifacies have become resistant to DDT."
Wikipedia is highly controversial and highly suspect because for a long time, anyone, like YOU for example, could edit each and every entry thereby inserting their own biases and disinformation. Of course, I'm sure you wouldn't insert disinformation, now would you?
You should have told her:
"Think Globally - Act Locally - Off Yourself"
"But am I correct to suspect that the vector of these diseases will,over time,develop a resistance to the DDT thus putting the people of various tropical regions right back where they started?"
Your question pre-supposes that some individuals will survive, develop limited or total immunity and pass it on genetically. I don't believe that any individuals, in significant numbers, survive. Hence, no passing on of survivability genes.
"I bought into it too.And pelicans supposedly are more numerous post-ban. Even my parents & other old-timers have said so & none of them are environmentalist wackos. Would you let me know if you find out anything, would you?I'd like to know the story on this as well."
The environmental wackos assured us that the Alaskan pipeline was the death knell of the caribou population. That population has exploded and they like hanging out next to the pipeline since it provides a source of warmth. That probably makes them more amorous, hence more caribou.
It's a naturally occuring bacteria that occurs in several variants - one form (var. kurstaki) kills worms, grubs, etc - often used by gardeners on squash vine borers, but also genetically engineered into corn to control cutworms, etc.
The israelensis form is quite useful for killing mosquitoes, gnats and other Diptera species. It's sold as "Mosquito Dunks," for ponds, birdbaths, etc. They're basically little floating donuts of mosquito death.
I personally favor a broader-spectrum approach - there are many chemicals that kill mosquitoes quite nicely (in addition to the BT mentioned above), like malathion, pyrethroids, etc. Bed nets impregnated with these alternatives are effective in limiting the spread as well.
This is categorically untrue, for a variety of reasons, not the least of which revolves around the reproductive cycle of a mosquito (2-3 weeks) versus that of a human being (~20 years).
Secondly, there are tons of observed instances of DDT resistance in mosquitoes. Sri Lanka, for one, is teeming with DDT resistant skeeters.
Vietnam stopped using DDT in 1991, yet their malaria rates plummeted. Why? Mosquito nets, distribution of anti-malarial drugs, and education (gasp!). They managed to reduce the death rate from malaria by 97% in six years, and the infection rate went down by 59%.
Ping, for your archives.
Does DDT kill only mosquitos? What other insects does it kill?
I have a nice swamp beside my house I'd like to erradicate.
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