Editing Cholera (section)

== Epidemiology ==
Cholera affects an estimated 2.8&nbsp;million people worldwide, and causes approximately 95,000&nbsp;deaths a year (uncertainty range: 21,000–143,000) {{as of|2015|lc=y}}.<ref>{{cite journal |last1=Ali |first1=Mohammad |last2=Nelson |first2=Allyson R. |last3=Lopez |first3=Anna Lena |last4=Sack |first4=David A. |title=Updated Global Burden of Cholera in Endemic Countries |journal=PLOS Neglected Tropical Diseases |date=4 June 2015 |volume=9 |issue=6 |pages=e0003832 |doi=10.1371/journal.pntd.0003832 |pmid=26043000 |pmc=4455997 |doi-access=free }}</ref><ref name="Loz2012">{{cite journal |last1=Lozano |first1=Rafael |last2=Naghavi |first2=Mohsen |last3=Foreman |first3=Kyle |last4=Lim |first4=Stephen |last5=Shibuya |first5=Kenji |last6=Aboyans |first6=Victor |last7=Abraham |first7=Jerry |last8=Adair |first8=Timothy |last9=Aggarwal |first9=Rakesh |last10=Ahn |first10=Stephanie Y |last11=AlMazroa |first11=Mohammad A |last12=Alvarado |first12=Miriam |last13=Anderson |first13=H Ross 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|last188=Zabetian |first188=Azadeh |last189=Zheng |first189=Zhi-Jie |last190=Lopez |first190=Alan D |last191=Murray |first191=Christopher JL |title=Global and regional mortality from 235 causes of death for 20 age groups in 1990 and 2010: a systematic analysis for the Global Burden of Disease Study 2010 |journal=The Lancet |date=December 2012 |volume=380 |issue=9859 |pages=2095–2128 |doi=10.1016/S0140-6736(12)61728-0 |pmid=23245604 |pmc=10790329 |s2cid=1541253 |hdl=10536/DRO/DU:30050819 |url=https://repozitorij.upr.si/Dokument.php?id=7123&dn= |hdl-access=free }}</ref> This occurs mainly in the developing world.<ref>{{cite journal |last1=Reidl |first1=Joachim |last2=Klose |first2=Karl E. |title=Vibrio cholerae and cholera: out of the water and into the host |journal=FEMS Microbiology Reviews |date=June 2002 |volume=26 |issue=2 |pages=125–139 |doi=10.1111/j.1574-6976.2002.tb00605.x |pmid=12069878 |doi-access=free }}</ref>

In the early 1980s, death rates are believed to have still been higher than three million a year.<ref name="Lancet2004" /> It is difficult to calculate exact numbers of cases, as many go unreported due to concerns that an outbreak may have a negative impact on the tourism of a country.<ref name="NEJM2006">{{cite journal | vauthors = Sack DA, Sack RB, Chaignat CL | title = Getting serious about cholera | journal = The New England Journal of Medicine | volume = 355 | issue = 7 | pages = 649–51 | date = August 2006 | pmid = 16914700 | doi = 10.1056/NEJMp068144 | s2cid = 23145226 }}</ref> As of 2004, cholera remained both [[epidemic]] and endemic in many areas of the world.<ref name="Lancet2004" />

Recent major outbreaks are the [[2010s Haiti cholera outbreak]] and the [[2016–2022 Yemen cholera outbreak]]. In October 2016, an [[2017 Yemen cholera outbreak|outbreak of cholera]] began in war-ravaged [[Yemen]].<ref>{{cite web|url=https://www.bbc.co.uk/news/world-middle-east-40369804 |title=The horrors of Yemen's spiralling cholera crisis |publisher=BBC |author=Johannes Bruwer |date=25 June 2017}}</ref> [[WHO]] called it "the worst cholera outbreak in the world".<ref>{{cite news|last1=Dwyer|first1=Colin |title=Yemen Now Faces 'The Worst Cholera Outbreak In The World,' U.N. Says|url=https://www.npr.org/sections/thetwo-way/2017/06/24/534236954/yemen-now-faces-the-worst-cholera-outbreak-in-the-world-u-n-says|access-date=25 June 2017|work=National Public Radio}}</ref> In 2019, 93% of the reported 923,037 cholera cases were from [[Yemen]] (with 1911 deaths reported).<ref name="who_report2020" /> Between September 2019 and September 2020, a global total of over 450,000 cases and over 900 deaths was reported; however, the accuracy of these numbers suffer from over-reporting from countries that report suspected cases (and not laboratory confirmed cases), as well as under-reporting from countries that do not report official cases (such as Bangladesh, India and Philippines).<ref name="who_report2020" />

Although much is known about the mechanisms behind the spread of cholera, researchers still do not have a full understanding of what makes cholera outbreaks happen in some places and not others. Lack of treatment of human [[feces]] and lack of treatment of drinking water greatly facilitate its spread. Bodies of water have been found to serve as a [[Natural reservoir|reservoir]] of infection, and seafood shipped long distances can spread the disease.

Cholera had disappeared from the [[Americas]] for most of the 20th century, but it reappeared toward the end of that century, beginning with a severe outbreak in Peru.<ref>{{cite journal | vauthors = Blake PA | title = Epidemiology of cholera in the Americas | journal = Gastroenterology Clinics of North America | volume = 22 | issue = 3 | pages = 639–60 | date = September 1993 | doi = 10.1016/S0889-8553(21)00094-7 | pmid = 7691740 }}</ref> This was followed by the [[2010s Haiti cholera outbreak]]<ref name="ecdc_cholera">{{Cite web|url=https://www.ecdc.europa.eu/en/all-topics-z/cholera/surveillance-and-disease-data/cholera-monthly|title=Cholera worldwide overview|date=May 30, 2023|website=www.ecdc.europa.eu}}</ref> and another outbreak of cholera in Haiti amid the [[2018–2023 Haitian crisis]].<ref>{{cite news |title=Cholera - Haiti |url=https://www.who.int/emergencies/disease-outbreak-news/item/2022-DON427 |access-date=1 February 2023 |work=www.who.int |language=en}}</ref> {{as of|August 2021}} the disease is endemic in Africa and some areas of eastern and western Asia (Bangladesh, India and Yemen).<ref name="ecdc_cholera" /> Cholera is not endemic in Europe; all reported cases had a travel history to endemic areas.<ref name="ecdc_cholera" />

=== History of outbreaks ===

{{Main|History of cholera}}
[[File:Il cholera di Palermo del 1835.jpg|thumb|upright=1.3|Disposal of dead bodies during the cholera epidemic in [[Palermo]] in 1835]]
[[File:Africa cholera2008b.jpg|thumb|upright=1.3|Map of the [[Zimbabwean cholera outbreak|2008–2009 cholera outbreak]] in [[sub-Saharan Africa]] showing the statistics as of 12 February 2009]]

The word cholera is from {{langx|el|χολέρα}} ''kholera'' from χολή ''kholē'' "bile". Cholera likely has its origins in the [[Indian subcontinent]] as evidenced by its prevalence in the region for centuries.<ref name="Lancet2004" />

References to cholera appear in the European literature as early as 1642, from the Dutch physician [[Jacobus Bontius|Jakob de Bondt's]] description in his De Medicina Indorum.<ref>{{Cite web|url=http://www.historyofmedicine.com/author/d/jacob-de-jacobus-bontius-bondt|title=All Entries by BONDT, Jacob de, Jacobus Bontius: HistoryofMedicine.com|website=www.historyofmedicine.com|language=en-us|access-date=2019-07-23}}</ref> (The "Indorum" of the title refers to the East Indies. He also gave first European descriptions of other diseases.) But at the time, the word "cholera" was historically used by European physicians to refer to any gastrointestinal upset resulting in yellow diarrhea. De Bondt thus used a common word already in regular use to describe the new disease. This was a frequent practice of the time. It was not until the 1830s that the name for severe yellow diarrhea changed in English from "cholera" to "cholera morbus" to differentiate it from what was then known as "Asiatic cholera", or that associated with origins in India and the East.

Early outbreaks in the Indian subcontinent are believed to have been the result of crowded, poor living conditions, as well as the presence of pools of [[stagnant water|still water]], both of which provide ideal conditions for cholera to thrive.<ref name="Rosenberg" /> The disease first spread by travelers along [[trade route]]s (land and sea) to [[Russia]] in 1817, later to the rest of [[Europe]], and from Europe to [[North America]] and the rest of the world,<ref name="Lancet2004" /> (hence the name "Asiatic cholera"<ref name="textbook" />). Seven [[cholera pandemic]]s have occurred since the early 19th century; the first one did not reach the Americas. The seventh [[pandemic]] originated in [[Indonesia]] in 1961.<ref>"[http://www.cbc.ca/news/technology/cholera-s-seven-pandemics-1.758504 Cholera's seven pandemics] {{webarchive|url=https://web.archive.org/web/20160302113041/http://www.cbc.ca/news/technology/cholera-s-seven-pandemics-1.758504 |date=2016-03-02 }}". CBC News. October 22, 2010.</ref>

The [[first cholera pandemic]] occurred in the Bengal region of India, near Calcutta starting in 1817 through 1824. The disease dispersed from India to Southeast Asia, the Middle East, Europe, and Eastern Africa.<ref name="Hays">{{cite book|url=https://books.google.com/books?id=GyE8Qt-kS1kC|title=Epidemics and Pandemics: Their Impacts on Human History| vauthors = Hays JN |publisher=[[ABC-CLIO]]|year=2005|isbn=978-1-85109-658-9|page=193}}</ref> The movement of British Army and Navy ships and personnel is believed to have contributed to the range of the pandemic, since the ships carried people with the disease to the shores of the Indian Ocean, from Africa to Indonesia, and north to China and Japan.<ref>{{Citation|last=McNeill|first=William H |title=Plagues and People|page=268}}.</ref>

The [[Second cholera pandemic|second pandemic]] lasted from 1826 to 1837 and particularly affected North America and Europe. Advancements in transport and global trade, and increased human migration, including soldiers, meant that more people were carrying the disease more widely.<ref>{{cite book|title=Something New Under The Sun: An Environmental History of the Twentieth Century World (The Global Century Series).|author=McNeil J}}</ref>

The [[Third cholera pandemic|third pandemic]] erupted in 1846, persisted until 1860, extended to North Africa, and reached North and South America. It was introduced to North America at [[Quebec, Canada]], via Irish immigrants from the Great Famine. In this pandemic, Brazil was affected for the first time.

The [[Fourth cholera pandemic|fourth pandemic]] lasted from 1863 to 1875, spreading from India to Naples and Spain, and reaching the United States at [[New Orleans, Louisiana]] in 1873. It spread throughout the Mississippi River system on the continent.

The [[Fifth cholera pandemic|fifth]] pandemic was from 1881 to 1896. It started in India and spread to Europe, Asia, and South America. The [[Sixth cholera pandemic|sixth pandemic]] ran from 1899 to 1923. These epidemics had a lower number of fatalities because physicians and researchers had a greater understanding of the cholera bacteria. Egypt, the Arabian peninsula, Persia, India, and the Philippines were hit hardest during these epidemics. Other areas, such as Germany in 1892 (primarily the city of Hamburg, where more than 8.600 people died)<ref>Richard Evans: ''Death in Hamburg: Society and Politics in the Cholera Years, 1830–1910.'' London 1987</ref> and Naples from 1910 to 1911, also had severe outbreaks.

The [[Seventh cholera pandemic|seventh pandemic]] originated in 1961 in Indonesia and is marked by the emergence of a new strain, nicknamed ''El Tor'', which still persists ({{as of|2018|lc=y}}<ref>{{Cite web|url=https://www.cdc.gov/cholera/index.html|title=Cholera – Vibrio cholerae infection {{!}} Cholera {{!}} CDC|date=2017-05-16|website=www.cdc.gov|language=en-us|access-date=2018-04-04}}</ref>) in developing countries.<ref>{{cite book|url=https://archive.org/details/plaguesworldhist00aber|url-access=limited|title=Plagues in World History|last=Aberth|first=John|publisher=Rowman & Littlefield|year=2011|isbn=978-0-7425-5705-5|location=Lanham, MD|page=[https://archive.org/details/plaguesworldhist00aber/page/n114 102]}}</ref> This pandemic had initially subsided about 1975 and was thought to have ended, but, as noted, it has persisted. There were a rise in cases in the 1990s and since.

Cholera became widespread in the 19th century.<ref>{{cite journal |last1=Huber |first1=Valeska |title=Pandemics and the politics of difference: rewriting the history of internationalism through nineteenth-century cholera |journal=Journal of Global History |date=November 2020 |volume=15 |issue=3 |pages=394–407 |doi=10.1017/S1740022820000236 |s2cid=228940685 |doi-access=free }}</ref> Since then it has killed tens of millions of people.<ref>[[Kelley Lee]] (2003) ''Health impacts of globalization: towards global governance''. Palgrave Macmillan. p.131. {{ISBN|0-333-80254-3}}</ref> In [[Russian Empire|Russia]] alone, between 1847 and 1851, more than one million people died from the disease.<ref>Geoffrey A. Hosking (2001). ''[https://books.google.com/books?id=oh-5AAmboMUC&pg=PA9 Russia and the Russians: a history]''. Harvard University Press. p.&nbsp;9. {{ISBN|0-674-00473-6}}</ref> It killed 150,000 Americans during the second pandemic.<ref>{{Cite book | author = Byrne JP | title = Encyclopedia of Pestilence, Pandemics, and Plagues: A–M | url = https://books.google.com/books?id=kRAInwEACAAJ| publisher = ABC-CLIO | year = 2008 | page = 99 | isbn = 978-0-313-34102-1}}</ref> Between 1900 and 1920, perhaps eight million people died of cholera in India.<ref>J. N. Hays (2005). ''[https://books.google.com/books?id=GyE8Qt-kS1kC&pg=PA347 Epidemics and pandemics: their impacts on human history]''. p.347. {{ISBN|1-85109-658-2}}</ref> Cholera officially became the first [[reportable disease]] in the United States due to the significant effects it had on health.<ref name="Lancet2004" /> [[John Snow (physician)|John Snow]], in [[England]], in 1854 was the first to identify the importance of contaminated water as its source of transmission.<ref name="Lancet2004" /> Cholera is now no longer considered a pressing health threat in Europe and North America due to [[water filtration|filtering]] and [[Water chlorination|chlorination]] of water supplies, but it still strongly affects populations in [[developing countries]].

In the past, vessels flew a yellow [[quarantine]] flag if any crew members or passengers had cholera. No one aboard a vessel flying a yellow flag would be allowed ashore for an extended period, typically 30 to 40 days.<ref>{{cite journal | vauthors = Sehdev PS | title = The origin of quarantine | journal = Clinical Infectious Diseases | volume = 35 | issue = 9 | pages = 1071–2 | date = November 2002 | pmid = 12398064 | doi = 10.1086/344062 | doi-access = free }}</ref>

Historically many different claimed remedies have existed in folklore. Many of the older remedies were based on the [[miasma theory]], that the disease was transmitted by bad air. Some believed that abdominal chilling made one more susceptible, and flannel and [[cholera belt]]s were included in army kits.<ref>{{cite journal | vauthors = Renbourn ET | title = The history of the flannel binder and cholera belt | journal = Medical History | volume = 1 | issue = 3 | pages = 211–25 | date = July 1957 | pmid = 13440256 | pmc = 1034286 | doi = 10.1017/S0025727300021281 }}</ref> In the 1854–1855 outbreak in Naples, homeopathic [[camphor]] was used according to [[Samuel Hahnemann|Hahnemann]].<ref>[http://www.legatum.sk/en:ahr:bayes-cholera-as-treated-by-dr-rubini-158-10355 www.legatum.sk] {{webarchive|url=https://web.archive.org/web/20130514193601/http://www.legatum.sk/en%3Aahr%3Abayes-cholera-as-treated-by-dr-rubini-158-10355 |date=2013-05-14 }}, ''The American Homoeopathic Review'', Vol. 06 No. 11–12, 1866, pages 401–403</ref> Dr. Hahnemann laid down three main remedies that would be curative in that disease; in early and simple cases '''camphor'''; in later stages with excessive cramping, '''cuprum''' or with excessive evacuations and profuse cold sweat, '''veratrum album'''. These are the Trio Cholera remedies used by homoeopaths around the world.<ref>{{cite web | url=https://www.homoeoscan.com/2015/09/trios-in-homeopathic-materia-medica-part-2.html | title=Trios in Homeopathic materia medica PART II }}</ref>
T. J. Ritter's ''Mother's Remedies'' book lists tomato syrup as a home remedy from northern America. [[Elecampane]] was recommended in the United Kingdom, according to William Thomas Fernie.<ref name="oldtimeremedies">{{cite web|title=Cholera Infantum, Tomatoes Will Relieve|url=http://www.oldtimeremedies.co.uk/labels/cholera.html|date=October 13, 2008|url-status=dead|archive-url=https://web.archive.org/web/20131224131642/http://www.oldtimeremedies.co.uk/labels/cholera.html|archive-date=December 24, 2013|access-date=February 18, 2013}}</ref> The first effective human vaccine was developed in 1885, and the first effective antibiotic was developed in 1948.

Cholera cases are much less frequent in developed countries where governments have helped to establish water sanitation practices and effective medical treatments.<ref>"Cholera", World Health Organization. [https://www.who.int/topics/cholera/about/en/index.html who.int] {{webarchive|url=https://web.archive.org/web/20131025005943/http://www.who.int/topics/cholera/about/en/index.html |date=2013-10-25 }}</ref> In the 19th century the United States, for example, had a severe cholera problem similar to those in some developing countries. It had three large cholera outbreaks in the 1800s, which can be attributed to ''Vibrio cholerae''{{'s}} spread through interior waterways such as the [[Erie Canal]] and the extensive Mississippi River valley system, as well as the major ports along the [[East Coast of the United States|Eastern Seaboard]] and their cities upriver.<ref>{{cite journal | vauthors = Pyle GF | title = The diffusion of cholera in the United States in the nineteenth century | journal = Geographical Analysis | volume = 1 | pages = 59–75 | year = 2010 | pmid = 11614509 | doi = 10.1111/j.1538-4632.1969.tb00605.x | doi-access = free }}</ref> The island of Manhattan in New York City touches the Atlantic Ocean, where cholera collected from river waters and ship discharges just off the coast. At this time, New York City did not have as effective a sanitation system as it developed in the later 20th century, so cholera spread through the city's water supply.<ref name="pmid7620035">{{cite journal | vauthors = Lacey SW | title = Cholera: calamitous past, ominous future | journal = Clinical Infectious Diseases | volume = 20 | issue = 5 | pages = 1409–19 | date = May 1995 | pmid = 7620035 | doi = 10.1093/clinids/20.5.1409 | s2cid = 45016958 }}</ref>

Cholera morbus is a historical term that was used to refer to [[gastroenteritis]] rather than specifically to what is now defined as the disease of cholera.<ref name="rosenberg">{{cite book|author1=Charles E. Rosenberg|title=The Cholera Years the United States in 1832, 1849, and 1866.|date=2009|publisher=University of Chicago Press|location=Chicago|isbn=978-0-226-72676-2|page=74|url=https://books.google.com/books?id=k2pL9c00rl4C&pg=PA74|url-status=live|archive-url=https://web.archive.org/web/20151109080652/https://books.google.com/books?id=k2pL9c00rl4C&pg=PA74|archive-date=2015-11-09}}</ref>

<gallery>
File:Cholera.jpg|[[Drawing]] of [[Personifications of death|Death]] bringing cholera, in ''[[Le Petit Journal (newspaper)|Le Petit Journal]]'' (1912)
File:Pedro II of Brazil and ministers of state.JPG|Emperor [[Pedro II of Brazil]] visiting people with cholera in 1855
File:Cholera 395.1.jpg|Hand bill from the [[Metropolitan Board of Health|New York City Board of Health]], 1832—the outdated public health advice demonstrates the lack of understanding of the disease and its causative factors.
</gallery>

=== Research ===
{{see also|Cholera vaccine}}

[[File:Robert Koch (Deutsche Cholera-Expedition in Ägypten 1884).jpg|thumb|upright=1.3|[[Robert Koch]] (third from the right) on a cholera research expedition in [[Egypt]] in 1884, one year after he identified ''V.&nbsp;cholerae'']]
[[File:How to avoid the Cholera 1848.jpg|thumb|upright=1.3|''How to avoid the cholera'' leaflet; [[Aberystwyth]]; August 1849]]
One of the major contributions to fighting cholera was made by the physician and pioneer medical scientist [[John Snow (physician)|John Snow]] (1813–1858), who in 1854 found a link between cholera and contaminated drinking water.<ref name="Rosenberg">{{cite book |author=Rosenberg, Charles E. |title=The cholera years: the United States in 1832, 1849 and 1866 |publisher=University of Chicago Press |location=Chicago |year=1987 |isbn=978-0-226-72677-9}}</ref> Dr. Snow proposed a microbial origin for epidemic cholera in 1849. In his major "state of the art" review of 1855, he proposed a substantially complete and correct model for the cause of the disease. In two pioneering epidemiological field studies, he was able to demonstrate human [[sewage]] contamination was the most probable disease vector in two [[1854 Broad Street cholera outbreak|major epidemics in London in 1854]].<ref>John Snow, [https://books.google.com/books?id=-N0_AAAAcAAJ&pg=PP5 ''The mode of communication of cholera''] {{webarchive|url=https://web.archive.org/web/20151106215135/https://books.google.com/books?id=-N0_AAAAcAAJ&pg=PP5 |date=2015-11-06 }}, 2nd ed. (London, England: John Churchill, 1855).</ref> His model was not immediately accepted, but it was increasingly seen as plausible as medical microbiology developed over the next 30 years or so. For his work on cholera, John Snow is often regarded as the "Father of Epidemiology".<ref>{{Cite web|date=14 March 2017|title=John Snow: A Legacy of Disease Detectives|url=https://blogs.cdc.gov/publichealthmatters/2017/03/a-legacy-of-disease-detectives/|access-date=2021-01-20|website=US Centers for Disease Control and Prevention|language=en-us}}</ref><ref>{{Cite web|title=Father of Modern Epidemiology|url=https://www.ph.ucla.edu/epi/snow/fatherofepidemiology.html|access-date=2021-01-20|website=www.ph.ucla.edu}}</ref><ref>{{Cite web|date=|title=John Snow|url=https://www.historyofvaccines.org/index.php/content/john-snow|access-date=2021-01-20|website=History of Vaccines|language=en|archive-date=2021-01-28|archive-url=https://web.archive.org/web/20210128091350/https://www.historyofvaccines.org/index.php/content/john-snow|url-status=dead}}</ref>

The bacterium was isolated in 1854 by Italian anatomist [[Filippo Pacini]],<ref>{{cite journal |first1=Fillipo |last1=Pacini |year=1854 |url=https://books.google.com/books?id=xdtQAAAAcAAJ&pg=PA397 |title=Osservazioni microscopiche e deduzioni patologiche sul cholera asiatico |archive-url=https://web.archive.org/web/20151118081405/https://books.google.com/books?id=xdtQAAAAcAAJ&pg=PA397 |archive-date=18 November 2015 |trans-title=Microscopic observations and pathological deductions on Asiatic cholera |language=it |journal=Gazzetta Medica Italiana |volume=4 |issue=50 |pages=397–401; 405–412 }} Reprinted as: {{cite book |last1=Pacini |first1=Filippo |title=Osservazioni microscopiche e deduzioni patologiche sul cholera asiatico |date=1854 |publisher=Federigo Bencini |url=https://books.google.com/books?id=F9s_AAAAcAAJ |language=it }}</ref> but its exact nature and his results were not widely known. In the same year, the [[Catalonia|Catalan]] [[Joaquim Balcells i Pascual]] discovered the bacterium.<ref name="Real Academia de la Historia 2018">{{cite web|year=2018|editor=[[Real Academia de la Historia]]|title=Joaquín Balcells y Pasqual|url=http://dbe.rah.es/biografias/18541/joaquin-balcells-y-pasqual|archive-url=https://web.archive.org/web/20190708211444/http://dbe.rah.es/biografias/18541/joaquin-balcells-y-pasqual|archive-date=2019-07-08|access-date=2020-08-01|language=es}}</ref><ref>{{cite web|year=2015|editor=[[:ca:Col·legi Oficial de Metges de Barcelona|Col·legi Oficial de Metges de Barcelona]]|title=Joaquim Balcells i Pascual|url=http://www.galeriametges.cat/galeria-fitxa.php?icod=EGMM|archive-url=https://web.archive.org/web/20200801110910/http://www.galeriametges.cat/galeria-fitxa.php?icod=EGMM|archive-date=2020-08-01|access-date=2020-08-01|language=ca}}</ref> In 1856 [[António Augusto da Costa Simões]] and [[José Ferreira de Macedo Pinto]], two Portuguese researchers, are believed to have done the same.<ref name="Real Academia de la Historia 2018" /><ref>{{cite book|author1=da Costa Simões, António Augusto|url=http://webopac.sib.uc.pt|title=Relatório da Direcção do Hospital de Cholericos de N.S. da Conceição em Coimbra|author2=de Macedo Pinto, José Ferreira|publisher=Imprensa da Universidade. The link leads to a library catalogue where the book can be found|year=1856|location=Coimbra|language=pt}}</ref>

Between the mid-1850s and the 1900s, cities in developed nations made massive investment in clean water supply and well-separated sewage treatment infrastructures. This eliminated the threat of cholera epidemics from the major developed cities in the world. In 1883, [[Robert Koch]] identified ''V.&nbsp;cholerae'' with a microscope as the bacillus causing the disease.<ref>{{cite book |last1=Aberth |first1=John |title=Plagues in World History |date=2011 |publisher=Rowman & Littlefield Publishers |isbn=978-1-4422-0796-7 |page=101 }}</ref>

[[Hemendra Nath Chatterjee]], a Bengali scientist, was the first to formulate and demonstrate the effectiveness of [[oral rehydration salt]] (ORS) to treat [[diarrhea]]. In his 1953 paper, published in ''[[The Lancet]]'', he states that [[promethazine]] can stop [[vomiting]] during cholera and then oral rehydration is possible. The formulation of the fluid replacement solution was 4&nbsp;g of [[sodium chloride]], 25&nbsp;g of [[glucose]] and 1000&nbsp;ml of [[water]].<ref>{{cite journal | vauthors = Ruxin JN | title = Magic bullet: the history of oral rehydration therapy | journal = Medical History | volume = 38 | issue = 4 | pages = 363–97 | date = October 1994 | pmid = 7808099 | pmc = 1036912 | doi = 10.1017/s0025727300036905 }}</ref><ref>{{cite journal | vauthors = Chatterjee HN | title = Control of vomiting in cholera and oral replacement of fluid | journal = Lancet | volume = 265 | issue = 6795 | pages = 1063 | date = November 1953 | pmid = 13110052 | doi = 10.1016/s0140-6736(53)90668-0 }}</ref>

[[File:Medical Scientist Prof. Sambhu Nath De.png|thumb|Prof. [[Sambhu Nath De]], who discovered the [[cholera toxin]] and successfully demonstrated the transmission of cholera pathogen by ''bacterial enteric toxin'']]
[[Indian people|Indian]] medical scientist [[Sambhu Nath De]] discovered the [[cholera toxin]], the ''[[animal model]] of cholera'', and successfully demonstrated the method of transmission of cholera pathogen ''Vibrio cholerae''.<ref>{{Cite web|url=https://inmemoryglobal.com/remembrance/sambhu-nath-de/|title=Sambhu Nath De|website=Inmemory|language=en-US|access-date=2019-12-05|archive-url=https://web.archive.org/web/20191205035801/https://inmemoryglobal.com/remembrance/sambhu-nath-de/|archive-date=2019-12-05|url-status=usurped}}</ref>

[[Robert Allan Phillips]], working at US [[Naval Medical Research Unit Two]] in Southeast Asia, evaluated the pathophysiology of the disease using modern laboratory chemistry techniques. He developed a protocol for rehydration. His research led the [[Lasker Foundation]] to award him its prize in 1967.<ref>{{cite web |url= http://www.laskerfoundation.org/awards/show/treatment-of-cholera/ |title= Albert Lasker Clinical Medical Research Award |publisher= Lasker Foundation |access-date= June 30, 2017 |url-status= dead |archive-url= https://web.archive.org/web/20170901014519/http://www.laskerfoundation.org/awards/show/treatment-of-cholera/ |archive-date= September 1, 2017 }}</ref>

More recently, in 2002, Alam, ''et al.'', studied stool samples from patients at the [[International Centre for Diarrhoeal Disease Research, Bangladesh|International Centre for Diarrhoeal Disease]] in [[Dhaka, Bangladesh]]. From the various experiments they conducted, the researchers found a correlation between the passage of ''V.&nbsp;cholerae'' through the human digestive system and an increased infectivity state. Furthermore, the researchers found the bacterium creates a hyperinfected state where [[gene]]s that control biosynthesis of [[amino acid]]s, [[iron]] uptake systems, and formation of periplasmic nitrate reductase complexes were induced just before defecation. These induced characteristics allow the cholera vibrios to survive in the "rice water" stools, an environment of limited oxygen and iron, of patients with a cholera infection.<ref name="Merrell2002">{{cite journal | vauthors = Merrell DS, Butler SM, Qadri F, Dolganov NA, Alam A, Cohen MB, Calderwood SB, Schoolnik GK, Camilli A | title = Host-induced epidemic spread of the cholera bacterium | journal = Nature | volume = 417 | issue = 6889 | pages = 642–5 | date = June 2002 | pmid = 12050664 | pmc = 2776822 | doi = 10.1038/nature00778 | bibcode = 2002Natur.417..642M }}</ref>

=== Global Strategy ===
In 2017, the WHO launched the "Ending Cholera: a global roadmap to 2030" strategy which aims to reduce cholera deaths by 90% by 2030.<ref name="who_fact">{{Cite web|url=https://www.who.int/news-room/fact-sheets/detail/cholera|title = Cholera}}</ref> The strategy was developed by the Global Task Force on Cholera Control (GTFCC) which develops country-specific plans and monitors progress.<ref>{{Cite web|url=https://www.gtfcc.org/|title=Global Task Force on Cholera Control|website=www.gtfcc.org}}</ref> The approach to achieve this goal combines surveillance, water sanitation, rehydration treatment and oral vaccines.<ref name="who_fact" /> Specifically, the control strategy focuses on three approaches: i) early detection and response to outbreaks to contain outbreaks, ii) stopping cholera transmission through improved sanitation and vaccines in hotspots, and iii) a global framework for cholera control through the GTFCC.<ref name="who_fact" />

The WHO and the GTFCC do not consider global cholera [[eradication of infectious diseases|eradication]] a viable goal.<ref>{{Cite report |title=Ending Cholera a Global Roadmap to 2030|publisher=Global Task Force on Cholera Control |date=2017 |url=https://www.who.int/cholera/publications/global-roadmap.pdf |archive-url=https://web.archive.org/web/20171018143604/http://www.who.int/cholera/publications/global-roadmap.pdf |archive-date=2017-10-18 |url-status=live |page=18}}</ref> Even though humans are the only host of cholera, the bacterium can persist in the environment without a human host.<ref name="Sack">{{cite journal |last1=Sack |first1=D. A. |title=A new era in the history of cholera: the road to elimination |journal=International Journal of Epidemiology |date=1 December 2013 |volume=42 |issue=6 |pages=1537–1540 |doi=10.1093/ije/dyt229 |pmid=24415587 |doi-access=free }}</ref> While global eradication is not possible, elimination of human to human transmission may be possible.<ref name="Sack" /> Local elimination is possible, which has been underway most recently during the [[2010s Haiti cholera outbreak]]. Haiti aims to achieve certification of elimination by 2022.<ref>{{cite book |title=National Plan for the Elimination of Cholera in Haiti 2013-2022 |date=February 2013 |publisher=Republic of Haiti, Ministry of Public Health and Population, National Directorate for Water Supply and Sanitation |url=https://www.paho.org/hq/dmdocuments/2013/cholera-haiti-nat-plan-elim-2013-2022.pdf |archive-url=https://web.archive.org/web/20180629005315/https://www.paho.org/hq/dmdocuments/2013/cholera-haiti-nat-plan-elim-2013-2022.pdf |archive-date=2018-06-29 |url-status=live }}</ref>

The GTFCC targets 47 countries, 13 of which have established vaccination campaigns.<ref name="who_report2020">{{cite book |title=International Coordinating Group (ICG) on Vaccine Provision for Cholera, Meningitis, and Yellow Fever |date=September 2020 |publisher=World Health Organization |isbn=978-92-4-002916-3 |url=https://www.who.int/publications/i/item/9789240029163 }}</ref>