Editing DDT (section)

==Malaria control{{anchor|Use_against_malaria}}==
[[Malaria]] remains the primary [[public health]] challenge in many countries. In 2015, there were 214 million cases of malaria worldwide resulting in an estimated 438,000 deaths, 90% of which occurred in Africa.<ref name=WHO15>{{cite web|title=Malaria Fact sheet N°94|url=https://www.who.int/mediacentre/factsheets/fs094/en/|publisher=WHO|access-date=2 February 2016|archive-date=September 3, 2014|archive-url=https://web.archive.org/web/20140903002027/http://www.who.int/mediacentre/factsheets/fs094/en/|url-status=live}}</ref> DDT is one of many tools to fight the disease. Its use in this context has been called everything from a "miracle weapon [that is] like [[Kryptonite]] to the mosquitoes",<ref name="salon">{{cite news |first=Kirsten |last=Weir |name-list-style=vanc |title=Rachel Carson's birthday bashing |url=http://www.salon.com/news/feature/2007/06/29/rachel_carson/ |work=Salon.com |date=June 29, 2007 |access-date=July 1, 2007 |archive-date=April 15, 2008 |archive-url=https://web.archive.org/web/20080415165815/http://www.salon.com/news/feature/2007/06/29/rachel_carson/ |url-status=live }}</ref> to "toxic colonialism".<ref>{{cite journal | last = Paull | first = John | name-list-style = vanc | title = Toxic Colonialism | journal = New Scientist | issue = 2628 | page = 25 | date = November 3, 2007 | volume = 196 | doi = 10.1016/S0262-4079(07)62774-2 | url = https://www.newscientist.com/article/mg19626280.400-toxic-colonialism.html/ | access-date = August 26, 2017 | archive-date = April 24, 2015 | archive-url = https://web.archive.org/web/20150424205340/http://www.newscientist.com/article/mg19626280.400-toxic-colonialism.html | url-status = live }}</ref>

Before DDT, eliminating mosquito breeding grounds by drainage or poisoning with [[Paris green]] or [[pyrethrum]] was sometimes successful. In parts of the world with rising living standards, the elimination of malaria was often a collateral benefit of the introduction of window screens and improved sanitation.<ref name="Gladwell"/> A variety of usually simultaneous interventions represents best practice. These include [[antimalarial drugs]] to prevent or treat infection; improvements in public health infrastructure to diagnose, sequester and treat infected individuals; [[mosquito net|bednets]] and other methods intended to keep mosquitoes from biting humans; and [[vector control]] strategies<ref name="wmr09">{{cite web | date = 2009 | publisher = World Health Organization | url = http://whqlibdoc.who.int/publications/2009/9789241563901_eng.pdf | title = World Malaria Report | access-date = December 17, 2009 | archive-date = January 12, 2010 | archive-url = https://web.archive.org/web/20100112144947/http://whqlibdoc.who.int/publications/2009/9789241563901_eng.pdf | url-status = live }}</ref> such as [[larvacide|larviciding]] with insecticides, ecological controls such as draining mosquito breeding grounds or introducing fish to eat larvae and [[indoor residual spraying]] (IRS) with insecticides, possibly including DDT. IRS involves the treatment of interior walls and ceilings with insecticides. It is particularly effective against mosquitoes, since many species rest on an indoor wall before or after feeding. DDT is one of 12 WHO–approved IRS insecticides.<ref name="AmJTrop"/>

The WHO's anti-malaria campaign of the 1950s and 1960s relied heavily on DDT and the results were promising, though temporary in developing countries. Experts tie malarial resurgence to multiple factors, including poor leadership, management and funding of malaria control programs; poverty; civil unrest; and increased [[irrigation]]. The evolution of resistance to first-generation drugs (e.g. [[chloroquine]]) and to insecticides exacerbated the situation.<ref name="DDTBP.1/2"/><ref name="Feachem2007">{{cite journal | vauthors = Feachem RG, Sabot OJ | title = Global malaria control in the 21st century: a historic but fleeting opportunity | journal = JAMA | volume = 297 | issue = 20 | pages = 2281–2284 | date = May 2007 | pmid = 17519417 | doi = 10.1001/jama.297.20.2281 }}</ref> Resistance was largely fueled by unrestricted agricultural use. Resistance and the harm both to humans and the environment led many governments to curtail DDT use in vector control and agriculture.<ref name=Chapin81/> In 2006 WHO reversed a longstanding policy against DDT by recommending that it be used as an indoor pesticide in regions where malaria is a major problem.<ref>{{cite news |url=https://www.washingtonpost.com/wp-dyn/content/article/2006/09/15/AR2006091501012.html |title=WHO Urges Use of DDT in Africa |date=September 16, 2006 |newspaper=Washington Post |access-date=August 22, 2017 |archive-date=September 2, 2017 |archive-url=https://web.archive.org/web/20170902230036/http://www.washingtonpost.com/wp-dyn/content/article/2006/09/15/AR2006091501012.html |url-status=live }}</ref>

Once the mainstay of anti-malaria campaigns, as of 2019 only five countries used DDT for Indoor Residual Spraying <ref>{{cite web |url= https://www.un.org/africarenewal/magazine/january-2022/widespread-use-ddt-malaria-control-worries-environmentalist|title=Widespread use of DDT for malaria control worries environmentalist|work=Africa Renewal|date=January 5, 2022 }}</ref>  

===Initial effectiveness===
When it was introduced in World War II, DDT was effective in reducing malaria [[morbidity]] and [[mortality rate|mortality]].<ref name=Dunlap/> WHO's anti-malaria campaign, which consisted mostly of spraying DDT and rapid treatment and diagnosis to break the transmission cycle, was initially successful as well. For example, in [[Sri Lanka]], the program reduced cases from about one million per year before spraying to just 18 in 1963<ref>{{cite book|title=The Coming Plague: Newly Emerging Diseases in a World Out of Balance|page=51|last=Garrett|first=Laurie|url=https://books.google.com/books?id=v9RY2PVOtOMC&pg=PA51|year=1994|publisher=Farrar, Straus and Giroux|isbn=978-1-4299-5327-6|access-date=August 29, 2022|archive-date=October 19, 2021|archive-url=https://web.archive.org/web/20211019223243/https://books.google.com/books?id=v9RY2PVOtOMC&pg=PA51|url-status=live}}</ref><ref>{{cite news | url = https://www.nytimes.com/2010/12/28/health/28global.html | title = Malaria: A Disease Close to Eradication Grows, Aided by Political Tumult in Sri Lanka | first = Donald G. | last = McNeil | name-list-style = vanc | work = The New York Times | date = December 27, 2010 | access-date = February 7, 2017 | archive-date = January 4, 2017 | archive-url = https://web.archive.org/web/20170104050535/http://www.nytimes.com/2010/12/28/health/28global.html | url-status = live }}</ref> and 29 in 1964. Thereafter the program was halted to save money and malaria rebounded to 600,000 cases in 1968 and the first quarter of 1969. The country resumed DDT vector control but the mosquitoes had evolved resistance in the interim, presumably because of continued agricultural use. The program switched to [[malathion]], but despite initial successes, malaria continued its resurgence into the 1980s.<ref name="Gordon">{{cite book|name-list-style=vanc|title=Mosquitoes, Malaria, and Man: A History of the Hostilities Since 1880|isbn=978-0-525-16025-0|first=Gordon A.|last=Harrison|url=https://books.google.com/books?id=mfkBr2oskyEC|year=1978|publisher=Dutton|access-date=August 29, 2022|archive-date=October 19, 2021|archive-url=https://web.archive.org/web/20211019210418/https://books.google.com/books?id=mfkBr2oskyEC|url-status=live}}</ref><ref>{{cite journal | vauthors = Karunaweera ND, Galappaththy GN, Wirth DF | title = On the road to eliminate malaria in Sri Lanka: lessons from history, challenges, gaps in knowledge and research needs | journal = Malaria Journal | volume = 13 | page = 59 | year = 2014 | pmid = 24548783 | pmc = 3943480 | doi = 10.1186/1475-2875-13-59 | doi-access = free }}</ref>

DDT remains on WHO's list of insecticides recommended for IRS. After the appointment of [[Arata Kochi]] as head of its anti-malaria division, WHO's policy shifted from recommending IRS only in areas of seasonal or episodic transmission of malaria, to advocating it in areas of continuous, intense transmission.<ref>
{{cite web | url =https://www.who.int/mediacentre/news/releases/2006/pr50/en/index.html | archive-url =https://web.archive.org/web/20060918220144/http://www.who.int/mediacentre/news/releases/2006/pr50/en/index.html | url-status =dead | archive-date =September 18, 2006 | publisher = World Health Organization | title = Who gives indoor use of DDT a clean bill of health for controlling malaria }}</ref> WHO reaffirmed its commitment to phasing out DDT, aiming "to achieve a 30% cut in the application of DDT world-wide by 2014 and its total phase-out by the early 2020s if not sooner" while simultaneously combating malaria. WHO plans to implement alternatives to DDT to achieve this goal.<ref>{{cite web | url =https://www.who.int/mediacentre/news/releases/2009/malaria_ddt_20090506/en/index.html | archive-url =https://web.archive.org/web/20090506212626/http://www.who.int/mediacentre/news/releases/2009/malaria_ddt_20090506/en/index.html | url-status =dead | archive-date =May 6, 2009 | title = Countries move toward more sustainable ways to roll back malaria | publisher = World Health Organization }}</ref>

South Africa continues to use DDT under WHO guidelines. In 1996, the country switched to alternative insecticides and malaria incidence increased dramatically. Returning to DDT and introducing new drugs brought malaria back under control.<ref>{{cite journal | vauthors = Yamey G | title = Roll Back Malaria: a failing global health campaign | journal = BMJ | volume = 328 | issue = 7448 | pages = 1086–1087 | date = May 2004 | pmid = 15130956 | pmc = 406307 | doi = 10.1136/bmj.328.7448.1086 }}</ref> Malaria cases increased in [[South America]] after countries in that continent stopped using DDT. Research data showed a strong negative relationship between DDT residual house sprayings and malaria. In a research from 1993 to 1995, Ecuador increased its use of DDT and achieved a 61% reduction in malaria rates, while each of the other countries that gradually decreased its DDT use had large increases.<ref name="Roberts 1997"/><ref>{{cite journal | vauthors = Griffing SM, Gamboa D, Udhayakumar V | title = The history of 20th century malaria control in Peru | journal = Malaria Journal | volume = 12 | page = 303 | year = 2013 | pmid = 24001096 | pmc = 3766208 | doi = 10.1186/1475-2875-12-303 | doi-access = free }}</ref><ref>{{cite journal | vauthors = Curtis CF | title = Should the use of DDT be revived for malaria vector control? | journal = Biomédica | volume = 22 | issue = 4 | pages = 455–461 | date = December 2002 | pmid = 12596442 | doi = 10.7705/biomedica.v22i4.1171| doi-access = free }}</ref>

===Mosquito resistance===
In some areas, resistance reduced DDT's effectiveness. WHO guidelines require that absence of resistance must be confirmed before using the chemical.<ref name="IRS-WHO">"
[http://whqlibdoc.who.int/hq/2006/WHO_HTM_MAL_2006.1112_eng.pdf Indoor Residual Spraying: Use of Indoor Residual Spraying for Scaling Up Global Malaria Control and Elimination] {{Webarchive|url=https://web.archive.org/web/20081002173139/http://whqlibdoc.who.int/hq/2006/WHO_HTM_MAL_2006.1112_eng.pdf |date=October 2, 2008 }}". World Health Organization, 2006.</ref> Resistance is largely due to agricultural use, in much greater quantities than required for disease prevention.

Resistance was noted early in spray campaigns. Paul Russell, former head of the [[Allies of World War II|Allied]] Anti-Malaria campaign, observed in 1956 that "resistance has appeared after six or seven years".<ref name="Gladwell"/> Resistance has been detected in Sri Lanka, [[Pakistan]], [[Turkey]] and [[Central America]] and it has largely been replaced by [[organophosphate]] or [[carbamate]] insecticides, e.g. malathion or [[bendiocarb]].<ref name="Curtis">{{cite web | vauthors = Curtis CF | url = http://ipmworld.umn.edu/chapters/curtiscf.htm | title = Control of Malaria Vectors in Africa and Asia | archive-url =  https://web.archive.org/web/20071002124232/http://ipmworld.umn.edu/chapters/curtiscf.htm | archive-date = October 2, 2007 | url-status = dead | date = February 1996 | publisher = University of Minnesota }}</ref>

In many parts of [[India]], DDT is ineffective.<ref>{{cite journal | vauthors = Sharma VP | title = Current scenario of malaria in India | journal = Parassitologia | volume = 41 | issue = 1–3 | pages = 349–353 | date = September 1999 | pmid = 10697882 }}</ref> Agricultural uses were banned in 1989 and its anti-malarial use has been declining. Urban use ended.<ref>{{cite journal |title=No Future in DDT: A case study of India |last=Agarwal |first=Ravi | name-list-style = vanc | journal=Pesticide Safety News |date=May 2001}}</ref> One study concluded that "DDT is still a viable insecticide in indoor residual spraying owing to its effectivity in well supervised spray operation and high excito-repellency factor."<ref name="mrc">{{cite journal | vauthors = Sharma SN, Shukla RP, Raghavendra K, Subbarao SK | title = Impact of DDT spraying on malaria transmission in Bareilly District, Uttar Pradesh, India | journal = Journal of Vector Borne Diseases | volume = 42 | issue = 2 | pages = 54–60 | date = June 2005 | pmid = 16161701 }}</ref>

Studies of malaria-vector mosquitoes in [[KwaZulu-Natal Province]], [[South Africa]] found susceptibility to 4% DDT (WHO's susceptibility standard), in 63% of the samples, compared to the average of 87% in the same species caught in the open. The authors concluded that "Finding DDT resistance in the vector ''An. arabiensis'', close to the area where we previously reported pyrethroid-resistance in the vector ''An. funestus'' Giles, indicates an urgent need to develop a strategy of [[insecticide resistance]] management for the malaria control programmes of southern Africa."<ref name="Hargreaves">{{cite journal | vauthors = Hargreaves K, Hunt RH, Brooke BD, Mthembu J, Weeto MM, Awolola TS, Coetzee M | title = Anopheles arabiensis and An. quadriannulatus resistance to DDT in South Africa | journal = Medical and Veterinary Entomology | volume = 17 | issue = 4 | pages = 417–422 | date = December 2003 | pmid = 14651656 | doi = 10.1111/j.1365-2915.2003.00460.x | s2cid = 22748077 }}</ref>

DDT can still be effective against resistant mosquitoes<ref name=PLoS1/> and the avoidance of DDT-sprayed walls by mosquitoes is an additional benefit of the chemical.<ref name="mrc"/> For example, a 2007 study reported that resistant mosquitoes avoided treated huts. The researchers argued that DDT was the best pesticide for use in IRS (even though it did not afford the most protection from mosquitoes out of the three test chemicals) because the other pesticides worked primarily by killing or irritating mosquitoes – encouraging the development of resistance.<ref name="PLoS1">{{cite journal | vauthors = Grieco JP, Achee NL, Chareonviriyaphap T, Suwonkerd W, Chauhan K, Sardelis MR, Roberts DR | title = A new classification system for the actions of IRS chemicals traditionally used for malaria control | journal = PLOS ONE | volume = 2 | issue = 8 | page = e716 | year = 2007 | pmid = 17684562 | pmc = 1934935 | doi = 10.1371/journal.pone.0000716 | doi-access = free | editor1-last = Krishna | editor1-first = Sanjeev | bibcode = 2007PLoSO...2..716G }}</ref> Others argue that the avoidance behavior slows eradication.<ref name="Musawenkosi">{{cite journal|vauthors=Mabaso ML, Sharp B, Lengeler C|date=August 2004|title=Historical review of malarial control in southern African with emphasis on the use of indoor residual house-spraying|journal=Tropical Medicine & International Health|volume=9|issue=8|pages=846–856|doi=10.1111/j.1365-3156.2004.01263.x|pmid=15303988|doi-access=free|s2cid=10018052}}</ref> Unlike other insecticides such as [[pyrethroid]]s, DDT requires long exposure to accumulate a lethal dose; however its irritant property shortens contact periods. "For these reasons, when comparisons have been made, better malaria control has generally been achieved with pyrethroids than with DDT."<ref name="Curtis"/> In India outdoor sleeping and night duties are common, implying that "the excito-repellent effect of DDT, often reported useful in other countries, actually promotes outdoor transmission".<ref>{{cite journal |title=DDT: The fallen angel |first=V. P. |last=Sharma |name-list-style=vanc |journal=Current Science |volume=85 |pages=1532–1537 |issue=11 |date=December 2003 |url=http://www.ias.ac.in/currsci/dec102003/1532.pdf |url-status=dead |archive-url=https://web.archive.org/web/20050518063647/http://www.ias.ac.in/currsci/dec102003/1532.pdf |archive-date=May 18, 2005 |df=mdy-all }}</ref>

===Residents' concerns===
{{Main|Indoor residual spraying#Residents' opposition to IRS}}
IRS is effective if at least 80% of homes and barns in a residential area are sprayed.<ref name="IRS-WHO"/> Lower coverage rates can jeopardize program effectiveness. Many residents resist DDT spraying, objecting to the lingering smell, stains on walls, and the potential exacerbation of problems with other insect pests.<ref name="Curtis"/><ref name="Musawenkosi"/><ref name="Thurow">"[http://www.mindfully.org/Health/Malaria-New-Strain.htm In Malaria War, South Africa Turns To Pesticide Long Banned in the West]" {{webarchive|url=https://web.archive.org/web/20071013113406/http://mindfully.org/Health/Malaria-New-Strain.htm |date=October 13, 2007 }}, Roger Thurow, ''[[The Wall Street Journal]]'', July 26, 2001</ref> [[Pyrethroid]] insecticides (e.g. [[deltamethrin]] and [[lambda-cyhalothrin]]) can overcome some of these issues, increasing participation.<ref name="Curtis"/>

===Human exposure===
A 1994 study found that [[South Africa]]ns living in sprayed homes have levels that are several orders of magnitude greater than others.<ref name="PineRiver"/> [[Breast milk]] from South African mothers contains high levels of DDT and DDE.<ref name="PineRiver"/> It is unclear to what extent these levels arise from home spraying vs food residues. Evidence indicates that these levels are associated with infant neurological abnormalities.<ref name="Curtis"/>

Most studies of DDT's human health effects have been conducted in developed countries where DDT is not used and exposure is relatively low.<ref name=Rogan05/><ref name="PineRiver"/><ref>{{cite news |url=https://www.sciencedaily.com/releases/2009/05/090504122058.htm |title=Unprecedented Use Of DDT Concerns Experts |last=Science Daily |date=May 9, 2009 |publisher=ScienceDaily.com |access-date=May 30, 2009 |archive-date=May 14, 2009 |archive-url=https://web.archive.org/web/20090514171439/http://www.sciencedaily.com/releases/2009/05/090504122058.htm |url-status=live }}</ref>

Illegal diversion to agriculture is also a concern as it is difficult to prevent and its subsequent use on crops is uncontrolled. For example, DDT use is widespread in Indian agriculture,<ref>{{cite news|url=http://economictimes.indiatimes.com/Markets/Commodities/Pesticide-level-in-veggies-fruits-rises/articleshow/4637527.cms|title=Pesticide level in veggies, fruits rises|last=Jayashree|first=Jayashree|name-list-style=vanc|date=10 June 2009|newspaper=[[The Economic Times]]|access-date=10 June 2009|archive-date=July 11, 2018|archive-url=https://web.archive.org/web/20180711064205/https://economictimes.indiatimes.com/Markets/Commodities/Pesticide-level-in-veggies-fruits-rises/articleshow/4637527.cms|url-status=live}}</ref> particularly [[mango]] production<ref>{{cite journal|last=Sanjana|date=June 13, 2009|title=A Whole Fruit|journal=[[Tehelka]] |volume=6|issue=23|url=http://www.tehelka.com/story_main42.asp?filename=cr130609a_whole.asp|access-date=June 8, 2009|archive-url=https://web.archive.org/web/20120405075828/http://www.tehelka.com/story_main42.asp?filename=cr130609a_whole.asp|archive-date=April 5, 2012|url-status=dead}}</ref> and is reportedly used by librarians to protect books.<ref>{{cite news|url=http://www.indianexpress.com/news/State-public-libraries-gasp-for-breath/472785|title=State public libraries gasp for breath|last=Chakravartty|first=Anupam|name-list-style=vanc|date=8 June 2009|newspaper=Indian Express|access-date=June 8, 2009|archive-date=April 13, 2020|archive-url=https://web.archive.org/web/20200413043945/http://archive.indianexpress.com/news/State-public-libraries-gasp-for-breath/472785|url-status=live}}</ref> Other examples include Ethiopia, where DDT intended for malaria control is reportedly used in coffee production,<ref>{{cite journal | last = Katima | first = Jamidu | name-list-style = vanc | date = June 2009 | title = African NGOs outline commitment to malaria control without DDT | url = http://www.pan-uk.org/pestnews/Issue/pn84/PN84_5.pdf | journal = Pesticides News | issue = 84 | page = 5 | url-status = dead | archive-url = https://web.archive.org/web/20160224231607/http://www.pan-uk.org/pestnews/Issue/pn84/PN84_5.pdf | archive-date = February 24, 2016 | df = mdy-all }}</ref> and Ghana where it is used for fishing.<ref>{{cite web|url=http://www.ghananewsagency.org/s_social/r_9596/ |title=Ministry moves to check unorthodox fishing methods |last=Ghana News Agency |date=November 17, 2009 |publisher=Ghana News Agency |access-date=November 18, 2009 |archive-url=https://web.archive.org/web/20120118212645/http://www.ghananewsagency.org/s_social/r_9596/ |archive-date=January 18, 2012 |url-status=live |df=mdy }}</ref><ref>{{cite news|url=http://news.myjoyonline.com/news/201004/45316.asp|title=Northern fisherfolks complain of committee's harassment|last=Appiah|first=Samuel|name-list-style=vanc|date=27 April 2010|publisher=Joy Online|access-date=April 27, 2010|url-status=dead|archive-url=https://web.archive.org/web/20100429002159/http://news.myjoyonline.com/news/201004/45316.asp|archive-date=April 29, 2010|df=mdy-all}}</ref> The residues in crops at levels unacceptable for export have been an important factor in bans in several tropical countries.<ref name="Curtis"/> Adding to this problem is a lack of skilled personnel and management.<ref name="Musawenkosi"/>

===Criticism of restrictions on DDT use===
Restrictions on DDT usage have been criticized by some organizations opposed to the environmental movement, including [[Roger Bate]] of the pro-DDT advocacy group [[Africa Fighting Malaria]] and the libertarian [[think tank]] [[Competitive Enterprise Institute]]; these sources oppose restrictions on DDT and attribute large numbers of deaths to such restrictions, sometimes in the millions.<ref name="Crichton">{{cite news |title=Rachel Carson Didn't Kill Millions of Africans |first=William |last=Souder |name-list-style=vanc |date=September 4, 2012 |work=Slate |url=http://www.slate.com/articles/health_and_science/science/2012/09/silent_spring_turns_50_biographer_william_souder_clears_up_myths_about_rachel_carson_.html |access-date=September 5, 2012 |archive-date=April 22, 2014 |archive-url=https://web.archive.org/web/20140422025120/http://www.slate.com/articles/health_and_science/science/2012/09/silent_spring_turns_50_biographer_william_souder_clears_up_myths_about_rachel_carson_.html |url-status=live }}</ref><ref>{{cite book |last1=Oreskes |first1=Naomi |author-link1=Naomi Oreskes |last2=Conway |first2=Erik M. |author-link2=Erik M. Conway |title=Merchants of Doubt |publisher=Bloomsbury |location=New York |year=2010 |isbn=978-1-59691-610-4 |title-link=Merchants of Doubt|page=217}}</ref><ref>{{cite journal|last=Baum|first=Rudy M.|date=June 4, 2007|title=Rachel Carson|journal=Chemical and Engineering News|volume=85|issue=23|page=5|url=http://pubs.acs.org/isubscribe/journals/cen/85/i23/html/8523editor.html}}</ref> These arguments were rejected as "outrageous" by former WHO scientist [[Socrates Litsios]].<ref name="salon"/> [[May Berenbaum]], [[University of Illinois]] entomologist, says, "to blame environmentalists who oppose DDT for more deaths than Hitler is worse than irresponsible".<ref name="salon"/> More recently, [[Michael Palmer (chemist)|Michael Palmer]], a professor of chemistry at the [[University of Waterloo]], has pointed out that DDT is still used to prevent malaria, that its declining use is primarily due to increases in manufacturing costs, and that in Africa, efforts to control malaria have been regional or local, not comprehensive.<ref>{{cite web |url=http://www.science.uwaterloo.ca/~mpalmer/stuff/DDT-myth.pdf |title=The ban of DDT did not cause millions to die from malaria |first=Michael |last=Palmer |date=29 September 2016 |publisher=University of Waterloo |access-date=August 14, 2018 |archive-date=June 16, 2021 |archive-url=https://web.archive.org/web/20210616080102/http://science.uwaterloo.ca/~mpalmer/stuff/DDT-myth.pdf |url-status=live }}</ref>
{{Quote box
 |quote  = The question that&nbsp;... malaria control experts must ask is not "Which is worse, malaria or DDT?" but rather "What are the best tools to deploy for malaria control in a given situation, taking into account the on-the-ground challenges and needs, efficacy, cost, and collateral effects{{snd}}both positive and negative{{snd}}to human health and the environment, as well as the uncertainties associated with all these considerations?"
 |width  = 50%
 |author = Hans Herren & Charles Mbogo<ref name="Herren Mbogo 2010 pp. a282–a282">{{cite journal | vauthors = Herren HR, Mbogo C | title = The role of DDT in malaria control | journal = Environmental Health Perspectives | volume = 118 | issue = 7 | pages = A282–A283; author reply A283 | date = July 2010 | pmid = 20601331 | doi = 10.1289/ehp.1002279 | pmc=2920925}}</ref>
}}

Criticisms of a DDT "ban" often specifically reference the 1972 United States ban (with the erroneous implication that this constituted a worldwide ban and prohibited use of DDT in vector control). Reference is often made to ''Silent Spring'', even though Carson never pushed for a DDT ban. [[John Quiggin]] and Tim Lambert wrote, "the most striking feature of the claim against Carson is the ease with which it can be refuted".<ref name="quig">{{cite news |first1=John |last1=Quiggin |first2=Tim |last2=Lambert |title=Rehabilitating Carson |newspaper=[[Prospect (magazine)|Prospect]] |date=May 2008 |url=http://www.prospectmagazine.co.uk/magazine/rehabilitatingcarson/ |name-list-style=vanc |access-date=June 22, 2012 |archive-date=April 13, 2020 |archive-url=https://web.archive.org/web/20200413043951/http://www.prospectmagazine.co.uk/magazine/rehabilitatingcarson |url-status=live }}</ref>

Investigative journalist Adam Sarvana and others characterize these notions as "myths" promoted principally by [[Roger Bate]] of the pro-DDT advocacy group [[Africa Fighting Malaria]] (AFM).<ref name="NRNS">{{cite news |url=http://www.nrns.org/index.php?option=com_content&view=article&id=51:bate-and-switch-how-a-free-market-magician-manipulated-two-decades-of-environmental-science- |title=Bate and Switch: How a free-market magician manipulated two decades of environmental science |last=Sarvana |first=Adam |name-list-style=vanc |date=May 28, 2009 |publisher=Natural Resources New Service |access-date=June 2, 2009 |url-status=dead |archive-url=https://web.archive.org/web/20100524144406/http://www.nrns.org/index.php?option=com_content&view=article&id=51%3Abate-and-switch-how-a-free-market-magician-manipulated-two-decades-of-environmental-science- |archive-date=May 24, 2010 |df=mdy }}</ref><ref name="Guts">{{cite book|last=Gutstein|first=Donald|name-list-style=vanc|title=Not a Conspiracy Theory: How Business Propaganda is Hijacking Democracy|url=https://books.google.com/books?id=zDRePgAACAAJ|year=2009|publisher=Key Porter Books |isbn=978-1-55470-191-9|access-date=August 29, 2022|archive-date=October 19, 2021|archive-url=https://web.archive.org/web/20211019223230/https://books.google.com/books?id=zDRePgAACAAJ|url-status=live}}. Relevant excerpt at {{cite magazine |url=https://thetyee.ca/Mediacheck/2010/01/22/DDTPropaganda/ |title=Inside the DDT Propaganda Machine |last=Gutstein |first=Donald |name-list-style=vanc |date=January 22, 2010 |magazine=[[The Tyee]] |access-date=January 22, 2010 |archive-date=January 25, 2010 |archive-url=https://web.archive.org/web/20100125172424/http://thetyee.ca/Mediacheck/2010/01/22/DDTPropaganda/ |url-status=live }}</ref>

===Alternatives===

====Insecticides====
{{Main|Indoor residual spraying}}
[[Organophosphate]] and [[carbamate]] insecticides, e.g. [[malathion]] and [[bendiocarb]], respectively, are more expensive than DDT per kilogram and are applied at roughly the same dosage. [[Pyrethroid]]s such as [[deltamethrin]] are also more expensive than DDT, but are applied more sparingly (0.02–0.3&nbsp;g/m<sup>2</sup> vs 1–2&nbsp;g/m<sup>2</sup>), so the net cost per house per treatment is about the same.<ref name="AmJTrop"/> DDT has one of the longest residual efficacy periods of any IRS insecticide, lasting 6 to 12 months. Pyrethroids will remain active for only 4 to 6 months, and organophosphates and carbamates remain active for 2 to 6 months. In many malaria-endemic countries, malaria transmission occurs year-round, meaning that the high expense of conducting a spray campaign (including hiring spray operators, procuring insecticides, and conducting pre-spray outreach campaigns to encourage people to be home and to accept the intervention) will need to occur multiple times per year for these shorter-lasting insecticides.<ref>{{Cite web|url=https://apps.who.int/iris/bitstream/handle/10665/69386/WHO_HTM_MAL_2006.1112_eng.pdf?sequence=1|title=Indoor Residual Spraying|date=2019|website=World Health Organization|access-date=March 14, 2019|archive-date=July 29, 2020|archive-url=https://web.archive.org/web/20200729031424/https://apps.who.int/iris/bitstream/handle/10665/69386/WHO_HTM_MAL_2006.1112_eng.pdf?sequence=1|url-status=live}}</ref>

In 2019, the related compound difluorodiphenyltrichloroethane ([[DFDT]]) was described as a potentially more effective and therefore potentially safer alternative to DDT.<ref>{{cite journal |last1=Zhu |first1=Xiaolong |last2=Hu |first2=Chunhua T. |last3=Yang |first3=Jingxiang |last4=Joyce |first4=Leo A. |last5=Qiu |first5=Mengdi |last6=Ward |first6=Michael D. |last7=Kahr |first7=Bart |title=Manipulating Solid Forms of Contact Insecticides for Infectious Disease Prevention |journal=Journal of the American Chemical Society |volume=141 |issue=42 |pages=16858–16864 |date=11 October 2019 |doi=10.1021/jacs.9b08125|pmid=31601104 |bibcode=2019JAChS.14116858Z |s2cid=204244148 }}</ref><ref name="NYT 17 October 2019">{{cite news |last1=Chang |first1=Kenneth |title=A Nazi Version of DDT Was Forgotten. Could It Help Fight Malaria? |url=https://www.nytimes.com/2019/10/17/science/nazi-ddt-malaria.html |archive-url=https://ghostarchive.org/archive/20220101/https://www.nytimes.com/2019/10/17/science/nazi-ddt-malaria.html |archive-date=2022-01-01 |url-access=limited |access-date=18 October 2019 |work=The New York Times |date=17 October 2019}}{{cbignore}}</ref>

====Non-chemical vector control====
Before DDT, malaria was successfully eliminated or curtailed in several tropical areas by removing or poisoning mosquito breeding grounds and larva habitats, for example by eliminating standing water. These methods have seen little application in Africa for more than half a century.<ref>{{cite journal | vauthors = Killeen GF, Fillinger U, Kiche I, Gouagna LC, Knols BG | title = Eradication of Anopheles gambiae from Brazil: lessons for malaria control in Africa? | journal = The Lancet. Infectious Diseases | volume = 2 | issue = 10 | pages = 618–627 | date = October 2002 | pmid = 12383612 | doi = 10.1016/S1473-3099(02)00397-3 }}</ref> According to CDC, such methods are not practical in Africa because "''Anopheles gambiae'', one of the primary vectors of malaria in Africa, breeds in numerous small pools of water that form due to rainfall&nbsp;... It is difficult, if not impossible, to predict when and where the breeding sites will form, and to find and treat them before the adults emerge."<ref>{{cite web |url=https://www.cdc.gov/malaria/malaria_worldwide/reduction/vector_control.html |title=Malaria Worldwide – How Can Malaria Cases and Deaths Be Reduced? – Larval Control and Other Vector Control Interventions |website=CDC.gov |date=January 29, 2019 |access-date=September 9, 2017 |archive-date=July 9, 2017 |archive-url=https://web.archive.org/web/20170709190523/https://www.cdc.gov/malaria/malaria_worldwide/reduction/vector_control.html |url-status=live }}</ref>

The relative effectiveness of IRS versus other malaria control techniques (e.g. bednets or prompt access to anti-malarial drugs) varies and is dependent on local conditions.<ref name="AmJTrop"/>

A WHO study released in January 2008 found that mass distribution of insecticide-treated mosquito nets and [[artemisinin]]–based drugs cut malaria deaths in half in malaria-burdened Rwanda and Ethiopia. IRS with DDT did not play an important role in mortality reduction in these countries.<ref>"[https://web.archive.org/web/20080215004936/http://www.who.int/malaria/docs/ReportGFImpactMalaria.pdf Impact of long-lasting insecticidal-treated nets (LLINs) and artemisinin-based combination therapies (ACTs) measured using surveillance data in four African countries]".  World Health Organization, January 31, 2008.</ref><ref>[http://www.sfgate.com/cgi-bin/article.cgi?f=/c/a/2008/02/01/MN4EUPS3D.DTL&type=health Malaria deaths halved in Rwanda and Ethiopia Better drugs, mosquito nets are the crucial tools] {{Webarchive|url=https://web.archive.org/web/20080210024708/http://www.sfgate.com/cgi-bin/article.cgi?f=%2Fc%2Fa%2F2008%2F02%2F01%2FMN4EUPS3D.DTL&type=health |date=February 10, 2008 }}, David Brown (Washington Post), ''SF Chronicle'', A-12, February 1, 2008.</ref>

[[Vietnam]] has enjoyed declining malaria cases and a 97% mortality reduction after switching in 1991 from a poorly funded DDT-based campaign to a program based on prompt treatment, bednets and pyrethroid group insecticides.<ref>"[http://www.afronets.org/files/malaria.pdf World Health Organization, A story to be shared: The successful fight against malaria in Vietnam]", November 6, 2000. {{webarchive |url=https://web.archive.org/web/20080226224853/http://www.afronets.org/files/malaria.pdf |date=February 26, 2008 }}</ref>

In Mexico, effective and affordable chemical and non-chemical strategies were so successful that the Mexican DDT manufacturing plant ceased production due to lack of demand.<ref name="PMC1119118">{{cite web |url=http://www.ipen.org/ipenweb/documents/work%20documents/ddt_ipenreport_english.pdf |title=DDT & Malaria |access-date=March 11, 2009 |archive-url=https://web.archive.org/web/20110726185356/http://www.ipen.org/ipenweb/documents/work%20documents/ddt_ipenreport_english.pdf |archive-date=July 26, 2011 |url-status=dead |df=mdy }}</ref>

A review of fourteen studies in sub-Saharan Africa, covering insecticide-treated nets, residual spraying, chemoprophylaxis for children, chemoprophylaxis or intermittent treatment for pregnant women, a hypothetical vaccine and changing front–line drug treatment, found decision making limited by the lack of information on the costs and effects of many interventions, the small number of cost-effectiveness analyses, the lack of evidence on the costs and effects of packages of measures and the problems in generalizing or comparing studies that relate to specific settings and use different methodologies and outcome measures. The two cost-effectiveness estimates of DDT residual spraying examined were not found to provide an accurate estimate of the cost-effectiveness of DDT spraying; the resulting estimates may not be good predictors of cost-effectiveness in current programs.<ref>{{cite journal | vauthors = Goodman CA, Mills AJ | title = The evidence base on the cost-effectiveness of malaria control measures in Africa | journal = Health Policy and Planning | volume = 14 | issue = 4 | pages = 301–312 | date = December 1999 | pmid = 10787646 | doi = 10.1093/heapol/14.4.301 | doi-access = free }}</ref>

However, a study in Thailand found the cost per malaria case prevented of DDT spraying ([[United States dollar|US$]]1.87) to be 21% greater than the cost per case prevented of [[lambda-cyhalothrin]]–treated nets (US$1.54),<ref>{{cite journal | vauthors = Kamolratanakul P, Butraporn P, Prasittisuk M, Prasittisuk C, Indaratna K | title = Cost-effectiveness and sustainability of lambdacyhalothrin-treated mosquito nets in comparison to DDT spraying for malaria control in western Thailand | journal = The American Journal of Tropical Medicine and Hygiene | volume = 65 | issue = 4 | pages = 279–284 | date = October 2001 | pmid = 11693869 | doi = 10.4269/ajtmh.2001.65.279 | doi-access = free }}</ref> casting some doubt on the assumption that DDT was the most cost-effective measure. The director of Mexico's malaria control program found similar results, declaring that it was 25% cheaper for Mexico to spray a house with synthetic pyrethroids than with DDT.<ref name="PMC1119118"/> However, another study in South Africa found generally lower costs for DDT spraying than for impregnated nets.<ref>{{cite journal | vauthors = Goodman CA, Mnzava AE, Dlamini SS, Sharp BL, Mthembu DJ, Gumede JK | title = Comparison of the cost and cost-effectiveness of insecticide-treated bednets and residual house-spraying in KwaZulu-Natal, South Africa | journal = Tropical Medicine & International Health | volume = 6 | issue = 4 | pages = 280–295 | date = April 2001 | pmid = 11348519 | doi = 10.1046/j.1365-3156.2001.00700.x | s2cid = 28103584 | doi-access = free }}</ref>

A more comprehensive approach to measuring the cost-effectiveness or efficacy of malarial control would not only measure the cost in dollars, as well as the number of people saved, but would also consider ecological damage and negative human health impacts. One preliminary study found that it is likely that the detriment to human health approaches or exceeds the beneficial reductions in malarial cases, except perhaps in epidemics. It is similar to the earlier study regarding estimated theoretical infant mortality caused by DDT and subject to the criticism also mentioned earlier.<ref>{{cite journal |url=http://www.jcu.edu.au/jrtph/vol/v04corin.pdf |vauthors=Corin SE, Weaver SA |year=2005 |title=A risk analysis model with an ecological perspective on DDT and malaria control in South Africa |journal=Journal of Rural and Tropical Public Health |volume=4 |issue=4 |pages=21–32 |access-date=January 30, 2006 |archive-date=March 6, 2006 |archive-url=https://web.archive.org/web/20060306003634/http://www.jcu.edu.au/jrtph/vol/v04corin.pdf |url-status=live }}</ref>

A study in the [[Solomon Islands]] found that "although impregnated bed nets cannot entirely replace DDT spraying without substantial increase in incidence, their use permits reduced DDT spraying".<ref>{{cite journal | vauthors = Over M, Bakote'e B, Velayudhan R, Wilikai P, Graves PM | title = Impregnated nets or DDT residual spraying? Field effectiveness of malaria prevention techniques in solomon islands, 1993–1999 | journal = The American Journal of Tropical Medicine and Hygiene | volume = 71 | issue = 2 Suppl | pages = 214–223 | date = August 2004 | pmid = 15331840 | doi = 10.4269/ajtmh.2004.71.214 | doi-access = free }}</ref>

A comparison of four successful programs against malaria in Brazil, India, Eritrea and Vietnam does not endorse any single strategy but instead states, "Common success factors included conducive country conditions, a targeted technical approach using a package of effective tools, data-driven decision-making, active leadership at all levels of government, involvement of communities, decentralized implementation and control of finances, skilled technical and managerial capacity at national and sub-national levels, hands-on technical and programmatic support from partner agencies, and sufficient and flexible financing."<ref>{{cite journal | vauthors = Barat LM | title = Four malaria success stories: how malaria burden was successfully reduced in Brazil, Eritrea, India, and Vietnam | journal = The American Journal of Tropical Medicine and Hygiene | volume = 74 | issue = 1 | pages = 12–16 | date = January 2006 | pmid = 16407339 | doi = 10.4269/ajtmh.2006.74.12 | doi-access = free }}</ref>

DDT resistant mosquitoes may be susceptible to pyrethroids in some countries. However, pyrethroid resistance in ''Anopheles'' mosquitoes is on the rise with resistant mosquitoes found in multiple countries.<ref>{{cite journal | vauthors = Mint Mohamed Lemine A, Ould Lemrabott MA, Niang EH, Basco LK, Bogreau H, Faye O, Ould Mohamed Salem Boukhary A | title = Pyrethroid resistance in the major malaria vector Anopheles arabiensis in Nouakchott, Mauritania | journal = Parasites & Vectors | volume = 11 | issue = 1 | pages = 344 | date = June 2018 | pmid = 29895314 | pmc = 5998517 | doi = 10.1186/s13071-018-2923-4 | doi-access = free }}</ref>