Ban of DDT did not cause a rise in malaria, or malaria deaths

October 23, 2018

Time to put that old canard to bed.

Malaria distribution was greatly reduced in the 20th century, reversing centuries of spreading. But malaria persisted into the 21st century. DDT helped reduce malaria, but the U.S. ban on DDT did not cause a rise in malaria infections or deaths. From a paper by Michael Palmer, M.D,. at Waterloo University.

Malaria distribution was greatly reduced in the 20th century, reversing centuries of spreading. But malaria persisted into the 21st century. DDT helped reduce malaria, but the U.S. ban on DDT did not cause a rise in malaria infections or deaths. From a paper by Michael Palmer, M.D,. at Waterloo University.

The U.S. ban on DDT in 1972 did not cause millions of unnecessary deaths to malaria. In fact, the worldwide death toll to malaria dropped for at least 18 years after the ban, plateaued for most of a decade, and dropped from 1999 to 2017. Malaria deaths fell dramatically, after the U.S. banned DDT from U.S. farms.

Not sure why Dr. Palmer wrote his essay in 2013, but he got most of the major sources and got most of the history accurately, His title, “The ban of DDT did not cause millions to die from malaria.”

It’s a good paper to bookmark, because it doesn’t always show up in Google searches in the U.S. — Waterloo being a university in Canada, in Waterloo, Ontario

www.science.uwaterloo.ca/~mpalmer/stuff/DDT-myth.pdf

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Annals of DDT: When they sprayed DDT from airplanes to stop polio

August 10, 2018

March of Dimes Foundation photo:

March of Dimes Foundation photo: “Nurses tended to polio patients in iron lung respirators at the Robert B. Green Memorial Hospital polio ward in San Antonio in 1950. It was a common scene throughout the polio crisis that swept Texas.” From the San Antonio Express-News article on the history of polio in the city.

It didn’t work.

In a desperate move to stop polio epidemics, after World War II but before the Salk polio vaccine was available, some American towns authorized aerial spraying of DDT over their cities.

Of course, DDT doesn’t stop viruses, and polio is a virus. Polio virus is not spread by a vector, an insect or other creature which might have been stopped by DDT, as mosquitoes spread malaria parasites and West Nile virus.

Aerial spraying of DDT against polio did not one thing.

A podcast from the Science History Institute discussed these misdirected events recently, and someone there did a sharp, short video to explain the issue.

YouTube explanation:

An animation drawn from episode 207 of Distillations podcast, DDT: The Britney Spears of Chemicals.

The podcast is a short 15 minutes, and fun, “Distillations.”

Americans have had a long, complicated relationship with the pesticide DDT, or dichloro-diphenyl-trichloroethane, if you want to get fancy. First we loved it, then we hated it, then we realized it might not be as bad as we thought. But we’ll never restore it to its former glory. And couldn’t you say the same about America’s once-favorite pop star?

We had a hunch that the usual narrative about DDT’s rise and fall left a few things out, so we talked to historian and CHF fellow Elena Conis. She has been discovering little-known pieces of this story one dusty letter at a time.

But first our associate producer Rigoberto Hernandez checks out some of CHF’s own DDT cans—that’s right, we have a DDT collection—and talks to the retired exterminator who donated them.

I bring it up here because in recent weeks there’s been a little surge on Twitter, and probably on Facebook and other places, in people claiming DDT causes polio, or causes symptoms so close to polio that physicians could never tell the difference. A lot of anti-vaccine advocates pile on, claiming that this would prove that the polio vaccine doesn’t work.

That’s all quite hooey-licious, off course. Polio’s paralysis of muscles in almost no way resembles acute DDT poisoning, which causes muscle misfiring instead of paralysis. As with almost every other disease, acute DDT poisoning can cause nausea; but DDT poisoning either kills its victim rather quickly, or goes away after a couple of weeks.

Polio doesn’t do that.

In the podcast, you’ll hear the common story of kids running behind DDT fogging trucks, because people thought DDT was harmless. In the concentrations in the DDT fogs, it would be almost impossible to ingest the 4 ounces or so of DDT required to get acute poisoning.

In any case, it’s one more odd facet of a long story of human relations to DDT and diseases. It’s worth a listen for history’s sake. But in this case, it’s entertaining, too. You’ll hear stories of people who opposed government actions to spray DDT, and who thought the government was too lax in its regulation and use of DDT.

More:

San Antonio Express-News file photo.

San Antonio Express-News file photo. “A young boy gets polio vaccine in this undated photo.”

Tip of the old scrub brush to Science History Institute (@SciHistoryOrg on Twitter).


Historic Deltoid: Indur Goklany on DDT, corrections from Tim Lambert

April 10, 2018

I’ll have to beg forgiveness from Tim Lambert, but in the interest of accuracy and good history, I have captured below the post Tim Lambert had on the old Deltoid blog (at the Seed Science Blogs site), dealing with Indur Goklany’s errors on DDT.

A bit of other history: Anthony Watts despises my posts (me, too, probably) and I am banned from his site for various sins including calling him out for suggesting Rachel Carson and President John F. Kennedy had more than an occasional handshake personal relationship (a bizarre charge Christopher Monckton repeats and exaggerates on in slightly different ways). Watts and I disagree on what we should regard as facts; I take the old collegiate debate and Scout Law positions, he sides with the Heartland Institute parody/comedy/hoax troupe.

Watts was having none of my corrections. Tim Lambert, who has researched this particular area of pro-DDT hoaxing more than anyone else, was kind enough to respond.

This is borrowed from the Internet Archive’s Wayback Machine, until, and then maybe a supplement to, the reappearance of Deltoid’s archives at the new site. As of April 10, 2018, I have not checked the links. If links don’t work, please tell me in comments, and I’ll work to get a new link to the old information where possible.

You should also know that Sri Lanka today is certified to be malaria-free, without DDT.

Below, Tim Lambert’s post on Indur Goklany’s errors about DDT history:

 

Indur Goklany, DDT and Malaria

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Ed Darrell points to a WUWT post by Indur Goklany which promotes the use of DDT to fight malaria instead of more effective measures. As with most of the DDT promoters, Goklany carefully avoids mentioning the way mosquitoes evolve resistance to insecticides. For example, here’s what he has on Sri Lanka:

For instance, malaria incidences in Sri Lanka (Ceylon) dropped from 2.8 million in the 1940s to less than 20 in 1963 (WHO 1999a, Whelan 1992). DDT spraying was stopped in 1964, and by 1969 the number of cases had grown to 2.5 million.

Now compare this with what really happened in Sri Lanka:

With widespread resistance of A. culicifacies to DDT, malathion spraying was introduced in 1975 in areas of P.falciparum transmission affording protection to nearly one million people. Towards the end of 1976 DDT spraying was completely discontinued and during 1977 exclusively malathion was used as an adulticide.

i-888470655207729222fb0f61fe5fa18a-oth_mal_cases_srl60-08.png

Note that the scale for malaria cases is logarithmic, so there was a factor of ten reduction in the number of cases in a few years after DDT spraying was discontinued.

The misinformation about DDT and malaria that Goklany spreads is harmful and could kill people. DDT still has a place in the fight against malaria (because of insecticide resistance we need as many different insecticides as possible), but there are more effective means available, and by trying to undercut the use of the best methods for fighting malaria, Goklany will be responsible for people dying from malaria.

[End, quote from Tim Lambert’s old Deltoid blog]

Now, is it possible that the comments will copy as well as the blog post? There are some good ones in there.

Here’s a try at copying the comments, below the fold.

 

Read the rest of this entry »


‘DDT has become harmless to mosquitoes today’

March 29, 2018

From India today, not news to anyone who follows the fight against malaria, and the fight to save a part of the planet to preserve human life.

DDT resistance prompted India to agree to stop production of DDT by 2020 — the last DDT factory remaining. India’s disease fighters tell of frustration trying to control malaria, because abuse of DDT has bred DDT resistant and immune mosquitoes. This is not news.

But India Today has a news hole to fill, and the continuing crises of vector-borne diseases force public health agencies to turn to “fourth generation” pesticides, as insects are now resistant to DDT and malathion.

The story out of New Delhi on March 13 almost adds some poetry to the issue. I repeat the story from India Today in full, partly because I love the lilt of Indian English, and because it tells the story of continuing attempts to get ahead of pesticide resistance in pests, attempts that just don’t seem to be doing the job.

Delhi’s civic agencies asked to use fourth generation pesticides to kill chemical-resistant insects

A small vehicle fogging streets of Delhi, India, with DDT, to fight mosquitoes. File photo from India Today, used to illustrate the story only.

A small vehicle fogging streets of Delhi, India, with DDT, to fight mosquitoes. File photo from India Today, used to illustrate the story only.

Pesticides such as DDT and malathion, which were once super weapons in the fight against mosquitoes, now seem to have become harmless perfume-like sprays for the blood-sucking parasites.

Scientists at the National Vector Borne Disease Control Programme (NVBDCP), Delhi which is the central nodal agency for prevention of diseases like malaria, dengue, filariasis, kala-azar, Japanese encephalitis and chikungunya, etc, in India has now recommended municipalities in the Capital and other parts of the country to shift to the 4th generation of pesticides that is also the last in the row.

These constitute certain bio-larvicides and insect growth regulators that stop the synthesis of critical hormones in mosquito larvae to prevent them from becoming adult. Only after attaining maturity, do the female Anopheles and Aedes Aegypti mosquitoes suck blood to get protein nutrition to lay eggs.

Scientists explain that the first generation of pesticides was DDT, used since World War II on soldiers in 1940s up till now, as its a powerful poison against mosquitoes. Later, its environmental effects, specifically on birds like vultures, reduced its usage globally.

Then came malathion, which had to be applied in huge quantities, paving the way for 3rdgeneration pesticides like synthetic pyrethroids and temephos. But with reports of mosquitoes developing tolerance towards all of these gradually, scientists are now recommending mixed and increased usage of the fourth generation of pesticides that is also the last line of defence in this class.

Experiments are still going on with genetically modified mosquitoes and introducing batches of mosquitoes injected with wolbachia bacteria in the wild to produce sterile eggs. A senior scientist with the NVBDCP, Civil Lines, said, Just like humans develop resistance towards antibiotics, mosquitoes have also evolved over the past 20-30 years to grow natural defence against DDT, malathion, etc. We are still using these two in virgin areas like forests of northeast India, Odisha, etc. successfully. But we have begun getting reports that even temephos and synthetic pyrethroids have stopped receiving the desired results against mosquitoes.

A pesticide is said to be successful when it kills over 90 per cent of the targeted insect or pest population. Over 3,500 species of mosquitoes, which play host to a number of disease-causing vectors such as zika, yellow fever, west Nile virus, etc. are said to be the deadliest animal family in the world. They kill 700 million people annually world over.
In Delhi itself, at least 10 people died of dengue last year and 9,271 people were affected.

The numbers of malaria and chikungunya cases recorded in 2017 stood at 1,142 and 940. In 2016, at least 21 dengue deaths were reported from various city hospitals. And this year, an early onset of the deadly trio dengue, malaria and chikungunya is expected with summer-like weather conditions already.

High temperature and presence of clear water in desert coolers, flower pots, coconut shells, etc, act as excellent breeding sites for the menacing insects.

We have asked municipalities to even use the fourth generation of pesticides pirimiphos-methyl and diflubenzuron in a mix with the previous generation pesticides to delay mosquitoes developing tolerance towards this in the future, the scientist explained. He said, over the years, the pesticides must be rotated in use so that their effectiveness on hardy mosquitoes does not go down.

Dr Himmat Singh, senior scientist at the National Institute of Malaria Research (NIMR), Dwarka, said, The benefit with these two latest pesticides is that they are only hormone-inhibitors, not poisons, and specific to mosquitoes. So they wouldnt have any effect on other insects, birds, mammals, fishes, etc. They are categorised as non-hazardous by WHO. However, their cost has been prohibitive so far, he said.

Delhi municipalities have begun their use after a meeting of scientists and bureaucrats of NVBDCP, NIMR, ministry of health and family welfare and the Central Insecticide Board (CIB) authorised their application in January, sources said.

Dr NR Das, head of the department of Public Health in east MCD said, We have already procured diflubenzuron on NVBDCP directions and been using it for one month satisfactorily. However, we will be able to ascertain its degree of effectiveness only after two to three months.

For at least a decade, India has been the world’s largest producer of DDT, and the largest user, spraying more DDT than the rest of the world together. China and North Korea were the only two other nations making DDT at the end of the 20th century, but both cut off production. Counter to popular conceptions, India has struggled to control malaria, often being the only nation in the world to account increases in the disease from year to year, since 2001. Malaria increased despite increasing DDT application.

To fight malaria effectively DDT spraying should be limited to Indoor Residual Spraying (IRS), which leaves a fine coat of DDT on the walls of sleeping rooms, where malaria-carrying mosquitoes bite humans, then pause on the walls to squeeze water out of the blood they’ve fed on, to reduce weight to fly. Broadscale spraying of DDT only speeds development of resistance in all mosquito species, and many other pests.

India is catching up with the rest of the world on DDT.

Tip of the old scrub brush to India Today’s Twitter feed.

 

 


Bad news from World Malaria Report 2017: Malaria fight stalled

December 20, 2017

Cover of World Malaria Report 2017. The fight against malaria is at a crossroads, WHO reports.

Cover of World Malaria Report 2017. The fight against malaria is at a crossroads, WHO reports.

This is the press release from the World Health Organization on the release of World Malaria Report 2017, on November 29, 2017:

Global response to malaria at crossroads

WHO report shows gains are levelling

News release

After unprecedented global success in malaria control, progress has stalled, according to the World malaria report 2017. There were an estimated 5 million more malaria cases in 2016 than in 2015. Malaria deaths stood at around 445 000, a similar number to the previous year.

“In recent years, we have made major gains in the fight against malaria,” said Dr Tedros Adhanom Ghebreyesus, Director-General of WHO. “We are now at a turning point. Without urgent action, we risk going backwards, and missing the global malaria targets for 2020 and beyond.”

The WHO Global Technical Strategy for Malaria calls for reductions of at least 40% in malaria case incidence and mortality rates by the year 2020. According to WHO’s latest malaria report, the world is not on track to reach these critical milestones.

A major problem is insufficient funding at both domestic and international levels, resulting in major gaps in coverage of insecticide-treated nets, medicines, and other life-saving tools.

Funding shortage

An estimated US$ 2.7 billion was invested in malaria control and elimination efforts globally in 2016. That is well below the US $6.5 billion annual investment required by 2020 to meet the 2030 targets of the WHO global malaria strategy.

In 2016, governments of endemic countries provided US$ 800 million, representing 31% of total funding. The United States of America was the largest international funder of malaria control programmes in 2016, providing US$1 billion (38% of all malaria funding), followed by other major donors, including the United Kingdom of Great Britain and Northern Ireland, France, Germany and Japan.

The global figures

The report shows that, in 2016, there were an estimated 216 million cases of malaria in 91 countries, up from 211 million cases in 2015. The estimated global tally of malaria deaths reached 445 000 in 2016 compared to 446 000 the previous year.

While the rate of new cases of malaria had fallen overall, since 2014 the trend has levelled off and even reversed in some regions. Malaria mortality rates followed a similar pattern.

The African Region continues to bear an estimated 90% of all malaria cases and deaths worldwide. Fifteen countries – all but one in sub-Saharan Africa – carry 80% of the global malaria burden.

“Clearly, if we are to get the global malaria response back on track, supporting the most heavily affected countries in the African Region must be the primary focus,” said Dr Tedros.

Controlling malaria

In most malaria-affected countries, sleeping under an insecticide-treated bednet (ITN) is the most common and most effective way to prevent infection. In 2016, an estimated 54% of people at risk of malaria in sub-Saharan Africa slept under an ITN compared to 30% in 2010. However, the rate of increase in ITN coverage has slowed since 2014, the report finds.

Spraying the inside walls of homes with insecticides is another effective way to prevent malaria. The report reveals a steep drop in the number of people protected from malaria by this method – from an estimated 180 million in 2010 to 100 million in 2016 – with the largest reductions seen in the African Region.

The African Region has seen a major increase in diagnostic testing in the public health sector: from 36% of suspected cases in 2010 to 87% in 2016. A majority of patients (70%) who sought treatment for malaria in the public health sector received artemisinin-based combination therapies (ACTs) – the most effective antimalarial medicines.

However, in many areas, access to the public health system remains low. National-level surveys in the African Region show that only about one third (34%) of children with a fever are taken to a medical provider in the public health sector.

Tackling malaria in complex settings

The report also outlines additional challenges in the global malaria response, including the risks posed by conflict and crises in malaria endemic zones. WHO is currently supporting malaria responses in Nigeria, South Sudan, Venezuela (Bolivarian Republic of) and Yemen, where ongoing humanitarian crises pose serious health risks. In Nigeria’s Borno State, for example, WHO supported the launch of a mass antimalarial drug administration campaign this year that reached an estimated 1.2 million children aged under 5 years in targeted areas. Early results point to a reduction in malaria cases and deaths in this state.

A wake-up call

“We are at a crossroads in the response to malaria,” said Dr Pedro Alonso, Director of the Global Malaria Programme, commenting on the findings of this year’s report. “We hope this report serves as a wake-up call for the global health community. Meeting the global malaria targets will only be possible through greater investment and expanded coverage of core tools that prevent, diagnose and treat malaria. Robust financing for the research and development of new tools is equally critical.”

Details of DDT use in the past year usually show up in the bowels of the report.


Map showing decline in DDT use, 2000 to 2014

September 22, 2017

Animation prepared by: UN Environment Chemicals and Health Branch 2016, with the latest information available and may not reflect the current status.

DDT use declining toward oblivion: UNEP caption – Source: DDT Expert Group. Report of the Effectiveness Evaluation on DDT Pursuant to the Article 16 of the Stockholm Convention Animation prepared by: UN Environment Chemicals and Health Branch 2016, with the latest information available and may not reflect the current status.

More than 180 nations signed the Persistent Organic Pollutants Treaty (POPs), often called the Stockholm Convention. The treaty pledges nations to voluntarily work to rid the planet of dangerous and toxic organic chemicals.

DDT is named in negotiation documents as one of the Dirty Dozen most toxic pollutants; however, because there was no alternative that performed exactly like DDT, the nations made a special addendum to the treaty to allow any nation to use DDT to fight disease vectors (insects that carry disease). The World Health Organization tracks use of DDT.

In 2001, 43 nations said they thought DDT would be useful. But by 2015, 33 of those nations gave up DDT, due to insects developing resistance and immunity.

India, the sole remaining nation where manufacture of DDT occurs, plans to stop all DDT production by 2020. India discovered that more DDT makes the insect pests more resistant faster, instead of beating disease carriers.

This map from the UN Environmental Program shows declining use of DDT, 2000 to 2014.  ][If that link doesn’t work, and it’s been iffy, try this one for information: https://www.unenvironment.org/explore-topics/chemicals-waste/what-we-do/persistent-organic-pollutants/alternatives-ddt]

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Annals of DDT: Eagles return to Buffalo, New York, in a big way

July 26, 2017

Caption from the Buffalo News: A bald eagle, one of a pair of eagles raising chicks in a nest on Strawberry Island in the Niagara River, fishes in the river, Saturday, March 9, 2013. (Derek Gee/Buffalo News)

Caption from the Buffalo News: A bald eagle, one of a pair of eagles raising chicks in a nest on Strawberry Island in the Niagara River, fishes in the river, Saturday, March 9, 2013. (Derek Gee/Buffalo News)

Among the greater chunks of powerful evidence for the damage the pesticide DDT did to birds is the dramatic recovery of some species as residual DDT levels drop, after DDT use ended in the U.S.

In 1970 only one nesting pair of bald eagles lived in New York state; I have not found whether they successfully fledged any young that year, but the odds are against it.

47 years later, eagles nest in after-recovery record numbers in New York, according to the venerable Buffalo News.

If you haven’t spotted the stark white head of a bald eagle somewhere in the Buffalo Niagara sky, it might be time to get out of the house more often.

Eagles are back in historically high numbers, according to a recent report by the state Department of Environmental Conservation.

The DEC reported a record-high 442 bald eagle breeding territories statewide in 2016, including 58 spots in six Western New York counties, including Erie, Niagara, Wyoming, Chautauqua, Cattaraugus and Allegany counties. That’s up from 38 spots in the region in 2012.

“It’s an astonishing number,” said Jim Landau, a count coordinator from the Hamburg Hawk Watch.

Recovery of bald eagles, and other endangered raptors including osprey, brown pelicans and peregrine falcons, is a great chapter in the book of successes of the Endangered Species Act and the rising conservation consciousness of the 1970s.

Recovery of all four species waited after EPA’s ban on crop use of DDT, until residual DDT levels in adult birds declined to a point the female birds could once again produce competent shells for the eggs they laid. DDT levels in fish and prey also had to drop to levels that would not poison chicks just hatched.

EPA banned DDT from U.S. farms in 1972, designating all DDT made in the country for export, to fight disease. Though DDT use declined world wide as resistance to the pesticide spread rapidly among mosquitoes and flies that were its target, most diseases DDT fought against declined. I estimate about 100 million fewer people died of malaria alone after the DDT ban. Birds were saved, and so were humans.

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