Diseases and epidemics of the 19th century included long-standing epidemic threats such as smallpox, typhus, yellow fever, and scarlet fever. In addition, cholera emerged as an epidemic threat and spread worldwide in six pandemics in the nineteenth century.
Epidemics of the 19th century were faced without the medical advances that made 20th-century epidemics much rarer and less lethal. Micro-organisms (viruses and bacteria) had been discovered in the 18th century, but it was not until the late 19th century that the experiments of Lazzaro Spallanzani and Louis Pasteur disproved spontaneous generation conclusively, allowing germ theory and Robert Koch's discovery of micro-organisms as the cause of disease transmission. Thus throughout the majority of the 19th century, there was only the most basic, common-sense understanding of the causes, amelioration, and treatment of epidemic disease.[ citation needed ]
The 19th century did, however, mark a transformation period in medicine. [1] This included the first uses of chloroform and nitrous dioxides as anesthesia, important discoveries in regards of pathology and the perfection of the autopsy, and advances in our understanding of the human body. [1] Medical institutions were also transitioning to new hospital styles to try to prevent the spread of disease and stop over crowding with the mixing of the poor and the sick which had been a common practice. [1] [2] With the increasing rise in urban population, disease and epidemic crisis became much more prevalent and was seen as a consequence of urban living. [1] [2] Problems arose as both governments and the medical professionals at the time tried to get a handle on the spread of disease. [1] They had yet to figure out what actually causes disease. [1] So as those in authority scrambled to make leaps and bounds in science and track down what may be the cause of these epidemics, entire communities would be lost to the grips of terrible ailments. [1] [2]
During these many outbreaks, members of the medical profession rapidly began trying different cures to treat their patients. [3] During the cholera epidemic of 1832, a doctor in London, Thomas Latta, discovered that he could greatly increase the survival rate of his patients by injecting saline solutions into their arms. [3] However, due to the wide range of medicines being touted as cures and treatments, his technique failed to gain widespread adoption. [3] Many other medical discoveries made in the 19th century failed to gain traction for similar reasons. With the increasing circulation of mass media and little content review in medical journals, almost anyone with or without proper education could publish a potential cure for disease. [3] Actual practicing medical professionals also had to compete with the ever expanding pharmacy companies that were all too ready to provide new elixirs and promising treatments for the epidemics of the time. [3]
Emerging from the medical chaos were legitimate and life changing treatments. The late 19th century was the beginning of widespread use of vaccines. [4] [5] The cholera bacterium was isolated in 1854 by Italian anatomist Filippo Pacini, [6] and a vaccine, the first to immunize humans against a bacterial disease, was developed by Spanish physician Jaume Ferran i Clua in 1885, [7] and by Russian–Jewish bacteriologist Waldemar Haffkine in July 1892. [8]
Antibiotic drugs did not appear until the middle of the 20th century. Sulfonamides did not appear until 1935, and penicillin, discovered in 1928, was not available as a treatment until 1950.[ citation needed ]
A big response and potential cure to these epidemics were better sanitation in the cities. [9] [10] Sanitation prior to this was very poor and sometimes attempts to get better sanitation often exacerbated the diseases, especially during the cholera epidemics because their understanding of diseases relied on the miasma (bad air) theory. [9] During the first cholera epidemic, Edwin Chadwick made an inquiry into sanitation and used quantitative data to link poor living conditions and disease and low life expectancy. [10] [9] As a result, the Board of Health in London took measure to improve drainage and ventilation around the city. Unfortunately, the measures helped clean the city but it further contaminated the River Thames (the primary drinking water for the city) and the epidemic got worse. [9]
During the second cholera pandemic of 1816–1837, the scientific community varied in its beliefs about its causes. In France, doctors believed cholera was associated with the poverty of certain communities or poor environment. Russians believed the disease was contagious and quarantined their citizens. The United States believed that cholera was brought by recent immigrants, specifically the Irish. Lastly, some British thought the disease might arise from divine intervention. [11]
During the third pandemic, Tunisia, which had not been affected by the two previous pandemics, thought Europeans had brought the disease. They blamed their sanitation practices. The prevalence of the disease in the South in areas of black populations convinced United States scientists that cholera was associated with African Americans. Current researchers note they lived near the waterways by which travelers and ships carried the disease and their populations were underserved with sanitation infrastructure and health care. [12]
The Soho outbreak in London in 1854 ended after the physician John Snow identified a neighborhood Broad Street pump as contaminated and convinced officials to remove its handle. [13] Snow believed that germ-contaminated water was the source of cholera, rather than particles in the air (referred to as "miasmata"). His study proved contaminated water was the main agent spreading cholera, although he did not identify the contaminant. Though Filippo Pacini had isolated Vibrio cholerae as the causative agent for cholera that year, it would be many years before miasma theory would fall out of favor.[ citation needed ]
In London, in June 1866 [14] ), a localized epidemic in the East End claimed 5,596 lives, just as the city was completing construction of its major sewage and water treatment systems. William Farr, using the work of John Snow, et al., as to contaminated drinking water being the likely source of the disease, relatively quickly identified the East London Water Company as the source of the contaminated water. Quick action prevented further deaths. [15]
During the fifth cholera pandemic, Robert Koch isolated Vibrio cholerae and proposed postulates to explain how bacteria caused disease. His work helped to establish the germ theory of disease. Prior to this time, many physicians believed that microorganisms were spontaneously generated, and disease was caused by direct exposure to filth and decay. Koch helped establish that the disease was more specifically contagious and was transmittable through the contaminated water supply. The fifth was the last serious European cholera outbreak, as cities improved their sanitation and water systems.[ citation needed ]
Cholera is an infection of the small intestine caused by the bacterium Vibrio cholerae . Cholera is transmitted primarily by drinking water or eating food [16] that has been contaminated by the cholera bacterium. The bacteria multiply in the small intestine; [17] the feces (waste product) of an infected person, including one with no apparent symptoms, can pass on the disease if it contacts the water supply by any means. [17]
History does not recount any incidents of cholera until the 19th century. Cholera came in seven waves, the last two of which occurred in the 20th century.[ citation needed ]
The first cholera pandemic started in 1816, spread across India by 1820, [18] and extended to Southeast Asia and Central Europe, lasting until 1826.
A second cholera pandemic began in 1829, reached Russia, causing the Cholera riots. It spread to Hungary, Germany and Egypt in 1831, [19] and London, Paris, Quebec, Ontario and New York City the following year. [15] [20] Cholera reached the Pacific coast of North America by 1834, reaching into the center of the country by steamboat and other river traffic. [21]
The third cholera pandemic began in 1846 and lasted until 1860. It hit Russia hardest, with over one million deaths. In 1846, cholera struck Mecca, killing over 15,000. [22] A two-year outbreak began in England and Wales in 1848, and claimed 52,000 lives. [23] In 1849, outbreak occurred again in Paris, and in London, killing 14,137, over twice as many as the 1832 outbreak. Cholera hit Ireland in 1849 and killed many of the Irish Famine survivors, already weakened by starvation and fever. [24] In 1849, cholera claimed 5,308 lives in the major port city of Liverpool, England, an embarkation point for immigrants to North America, and 1,834 in Hull, England. [15] Cholera spread throughout the Mississippi River system. [15] Thousands died in New York City, a major destination for Irish immigrants. [15] Cholera killed 200,000 people in Mexico. [25] That year, cholera was transmitted along the California, Mormon and Oregon Trails, killing people that are believed to have died on their way to the California Gold Rush, Utah and Oregon in the cholera years of 1849–1855. [15] [26] [27] [28] In 1851, a ship coming from Cuba carried the disease to Gran Canaria, [29] killing up to 6,000 people. [30]
The pandemic spread east to Indonesia by 1852, and China and Japan in 1854. The Philippines were infected in 1858 and Korea in 1859. In 1859, an outbreak in Bengal contributed to transmission of the disease by travelers and troops to Iran, Iraq, Arabia and Russia. [22] Japan suffered at least seven major outbreaks of cholera between 1858 and 1902. The Ansei outbreak of 1858–60, for example, is believed to have killed between 100,000 and 200,000 people in Tokyo alone. [31] An outbreak of cholera in Chicago in 1854 took the lives of 5.5% of the population (about 3,500 people). [15] [32] In 1853–4, London's epidemic claimed 10,738 lives. Throughout Spain, cholera caused more than 236,000 deaths in 1854–55. [33] In 1854, it entered Venezuela; Brazil also suffered in 1855. [25]
The fourth cholera pandemic (1863–1875) spread mostly in Europe and Africa. At least 30,000 of the 90,000 Mecca pilgrims died from the disease. Cholera ravaged northern Africa in 1865 and southeastward to Zanzibar, killing 70,000 in 1869–70. [34] Cholera claimed 90,000 lives in Russia in 1866. [35] The epidemic of cholera that spread with the Austro-Prussian War (1866) is estimated to have killed 165,000 people in the Austrian Empire. [36] In 1867, 113,000 died from cholera in Italy. [37] and 80,000 in Algeria. [34]
Outbreaks in North America in 1866–1873 killed some 50,000 Americans. [27] In 1866, localized epidemics occurred in the East End of London, [14] [15] in southern Wales, and Amsterdam. In the 1870s, cholera spread in the U.S. as an epidemic from New Orleans along the Mississippi River and to ports on its tributaries.[ citation needed ]
In the fifth cholera pandemic (1881–1896), according to Dr A. J. Wall, the 1883–1887 part of the epidemic cost 250,000 lives in Europe and at least 50,000 in the Americas. Cholera claimed 267,890 lives in Russia (1892); [38] 120,000 in Spain; [39] 90,000 in Japan and over 60,000 in Persia. [38] In Egypt, cholera claimed more than 58,000 lives. The 1892 outbreak in Hamburg killed 8,600 people.[ citation needed ]
Smallpox is caused by either of the two viruses, Variola major and Variola minor. Smallpox vaccine was available in Europe, the United States, and the Spanish Colonies during the last part of the century. [4] [5] The Latin names of this disease are Variola Vera. The words come from various (spotted) or varus (pimple). In England, this disease was first known as the "pox" or the "red plague". Smallpox settles itself in small blood vessels of the skin and in the mouth and throat. The symptoms of smallpox are rash on the skin and blisters filled with raised liquid.[ citation needed ]
The disease killed an estimated 400,000 Europeans annually during the 19th century and one-third of all the blindness of that time was caused by smallpox. 20 to 60% of all the people that were infected died and 80% of all the children with the infection also died. It caused also many deaths in the 20th century, over 300–500 million. Wolfgang Amadeus Mozart also had smallpox when he was only 11 years old. He survived the smallpox outbreak in Austria.[ citation needed ]
Epidemic typhus is caused by the bacteria Rickettsia Prowazekii; it comes from lice. Murine typhus is caused by the Rickettsia Typhi bacteria, from the fleas on rats. Scrub typhus is caused by the Orientia Tsutsugamushi bacteria, from the harvest mites on humans and rodents. Queensland tick typhus is caused by the Rickettsia Australis bacteria, from ticks.[ citation needed ]
During Napoleon's retreat from Moscow in 1812, more French soldiers died of typhus than were killed by the Russians. [40] A major epidemic occurred in Ireland between 1816 and 1819, during the Year Without a Summer; an estimated 100,000 Irish perished. Typhus appeared again in the late 1830s, and between 1846 and 1849 during the Great Irish Famine. Spreading to England, and called "Irish fever", it was noted for its virulence. It killed people of all social classes, as lice were endemic and inescapable, but it hit particularly hard in the lower or "unwashed" social strata. In Canada alone, the typhus epidemic of 1847 killed more than 20,000 people from 1847 to 1848, mainly Irish immigrants in fever sheds and other forms of quarantine, who had contracted the disease aboard coffin ships. [41] In the United States, epidemics occurred in Baltimore, Memphis and Washington DC between 1865 and 1873, and during the US Civil War.[ citation needed ]
This disease is transmitted by the bite of female mosquito; the higher prevalence of transmission by Aedes aegypti has led to it being known as the Yellow Fever Mosquito. The transmission of yellow fever is entirely a matter of available habitat for vector mosquito and prevention such as mosquito netting. They mostly infect other primates, but humans can be infected. The symptoms of the fever are: Headaches, back and muscle pain, chills and vomiting, bleeding in the eyes and mouth, and vomit containing blood.[ citation needed ]
Yellow fever accounted for the largest number of the 19th-century's individual epidemic outbreaks, and most of the recorded serious outbreaks of yellow fever occurred in the 19th century. It is most prevalent in tropical-like climates, but the United States was not exempted from the fever. [42] New Orleans was plagued with major epidemics during the 19th century, most notably in 1833 and 1853. At least 25 major outbreaks took place in the Americas during the 18th and 19th centuries, including particularly serious ones in Santo Domingo in 1803 [43] [44] and Memphis in 1878. [45] Major outbreaks occurred repeatedly in Gibraltar; outbreaks in 1804, 1814, and again in 1828. [46] Barcelona suffered the loss of several thousand citizens during an outbreak in 1821. Urban epidemics continued in the United States until 1905, with the last outbreak affecting New Orleans. [47]
The third plague pandemic was a major bubonic plague pandemic that began in Yunnan, China in 1855. [48] This episode of bubonic plague spread to all inhabited continents in the 1890s and first years of the 1900s, and ultimately led to more than 12,000,000 deaths in India and China, with about 10,000,000 killed in India alone. [49]
A natural reservoir of plague is located in western Yunnan and is an ongoing health risk today. The third pandemic of plague originated in this area after a rapid influx of Han Chinese to exploit the demand for minerals, primarily copper, in the latter half of the 19th century. [50] By 1850, the population had exploded to over 7,000,000 people. Increasing transportation throughout the region brought people in contact with plague-infected fleas, the primary vector between the yellow-breasted rat (Rattus flavipectus) and humans. The spread of European empires and the development of new forms of transport such as the steam engine made it easier for both humans and rats to spread the disease along existing trade routes.[ citation needed ]
Haemolytic streptococcus, which was identified in the 1880s, [51] causes scarlet fever, which is a bacterial disease. [52] Scarlet fever spreads through respiratory droplets and children between the ages of 5 and 15 years were most affected by scarlet fever. [53] Scarlet fever had several epidemic phases, and around 1825 to 1885 outbreaks began to recur cyclically and often highly fatal. [54] In the mid-19th century, the mortality caused by scarlet fever rose in England and Wales. [55] The major outbreak in England and Wales took place during 1825–1885 with high mortality marking this as remarkable. [52] There were several other notable outbreaks across Europe, South America, and the United States in the 19th century. [53]
In the UK, scarlet fever was considered benign for two centuries, but fatal epidemics were seen in the 1700s. [56] Scarlet fever broke out in England in the 19th century and was responsible for an enormous number of deaths in the 60-year period from 1825 to 1885; decades that followed had lower levels of annual mortality from scarlet fever. [52] In NW England there was heavy mortality in Liverpool. [52] Babies born in Liverpool with a birthday in 1861 were only expected to live 26 years, and in larger cities, life expectancy was less than 35 years. [51] Over time, the life expectancy changed as well as the number of fatalities from scarlet fever. [51] There was a reduction in child mortality from scarlet fever when you compare the decades, 1851–60 and 1891–1900. [51] The decline of mortality seen for scarlet fever was noticed after the identification of streptococcus, [51] but the decline was not associated with a treatment. [51] A treatment would not be available until the introduction of sulphonamides in the 1930s, and the decline in mortality was due to the quality of air, food, and water improving. [51] Outbreaks of scarlet fever also took place in Dublin in 1896 with 1,354 cases and 149 deaths, Norway from 1862 to 1884, Scotland in 1861, and in the rest of United Kingdom. [53] The United Kingdom saw cases in Canterbury from 1839 to 1865 with 305 deaths, Bristol in 1870 with 106 deaths and in 1875, and Manchester in 1886 with six cases. [53]
Chile reported scarlet fever the first time in 1827 and highest rates were seen during winter months. [53] The disease spread from Valparaiso to Santiago from 1831 to 1832 and claimed 7,000 lives. [53] There were multiple outbreaks in different locations of Chile, including Copaipo in 1875 and Caldera in 1876. [53]
Similarly to Europe, America considered scarlet fever to be benign for two centuries. [56] In the early 19th century the scarlet fever impact drastically changed and lethal epidemics started to arise in the United States. [56] The United States had a notable outbreak of scarlet fever in Minnesota in 1847 [53] and Augusta, Georgia had a lethal epidemic in 1832–1833. [56] Scarlet fever had low mortality rates in New York for many years before 1828, but remained high for long after. [56] Cases of scarlet fever were also seen in Boston during a period of decreasing severity after 1885. [56] Boston City Hospital opened a scarlet fever pavilion in 1887 to house patients with infectious diseases and saw nearly 25,000 patients during 1895–1905. [56] In the mid-1800s, more specific epidemiological information was emerging and incidence in infants were found to be low. [56] In 1870, the US census showed a decrease in scarlet fever mortality in children below the age of one. [56]
Cholera is an infection of the small intestine by some strains of the bacterium Vibrio cholerae. Symptoms may range from none, to mild, to severe. The classic symptom is large amounts of watery diarrhea lasting a few days. Vomiting and muscle cramps may also occur. Diarrhea can be so severe that it leads within hours to severe dehydration and electrolyte imbalance. This may result in sunken eyes, cold skin, decreased skin elasticity, and wrinkling of the hands and feet. Dehydration can cause the skin to turn bluish. Symptoms start two hours to five days after exposure.
A pandemic is an epidemic of an infectious disease that has a sudden increase in cases and spreads across a large region, for instance multiple continents or worldwide, affecting a substantial number of individuals. Widespread endemic diseases with a stable number of infected individuals such as recurrences of seasonal influenza are generally excluded as they occur simultaneously in large regions of the globe rather than being spread worldwide.
Vibrio cholerae is a species of Gram-negative, facultative anaerobe and comma-shaped bacteria. The bacteria naturally live in brackish or saltwater where they attach themselves easily to the chitin-containing shells of crabs, shrimp, and other shellfish. Some strains of V. cholerae are pathogenic to humans and cause a deadly disease called cholera, which can be derived from the consumption of undercooked or raw marine life species or drinking contaminated water.
Zymotic disease was a 19th-century medical term for acute infectious diseases, especially "chief fevers and contagious diseases ".
The germ theory of disease is the currently accepted scientific theory for many diseases. It states that microorganisms known as pathogens or "germs" can cause disease. These small organisms, which are too small to be seen without magnification, invade humans, other animals, and other living hosts. Their growth and reproduction within their hosts can cause disease. "Germ" refers to not just a bacterium but to any type of microorganism, such as protists or fungi, or other pathogens that can cause disease, such as viruses, prions, or viroids. Diseases caused by pathogens are called infectious diseases. Even when a pathogen is the principal cause of a disease, environmental and hereditary factors often influence the severity of the disease, and whether a potential host individual becomes infected when exposed to the pathogen. Pathogens are disease-carrying agents that can pass from one individual to another, both in humans and animals. Infectious diseases are caused by biological agents such as pathogenic microorganisms as well as parasites.
El Tor is a particular strain of the bacterium Vibrio cholerae, the causative agent of cholera. Also known as V. cholerae biotype eltor, it has been the dominant strain in the seventh global cholera pandemic. It is distinguished from the classic strain at a genetic level, although both are in the serogroup O1 and both contain Inaba, Ogawa and Hikojima serotypes. It is also distinguished from classic biotypes by the production of hemolysins.
Vibrio is a genus of Gram-negative bacteria, possessing a curved-rod (comma) shape, several species of which can cause foodborne infection or soft-tissue infection called Vibriosis. Infection is commonly associated with eating undercooked seafood. Being highly salt tolerant and unable to survive in freshwater, Vibrio spp. are commonly found in various salt water environments. Vibrio spp. are facultative anaerobes that test positive for oxidase and do not form spores. All members of the genus are motile. They are able to have polar or lateral flagellum with or without sheaths. Vibrio species typically possess two chromosomes, which is unusual for bacteria. Each chromosome has a distinct and independent origin of replication, and are conserved together over time in the genus. Recent phylogenies have been constructed based on a suite of genes.
The miasma theory is an abandoned medical theory that held that diseases—such as cholera, chlamydia, or the Black Death—were caused by a miasma, a noxious form of "bad air", also known as night air. The theory held that epidemics were caused by miasma, emanating from rotting organic matter. Though miasma theory is typically associated with the spread of contagious diseases, some academics in the early nineteenth century suggested that the theory extended to other conditions as well, e.g. one could become obese by inhaling the odor of food.
Globalization, the flow of information, goods, capital, and people across political and geographic boundaries, allows infectious diseases to rapidly spread around the world, while also allowing the alleviation of factors such as hunger and poverty, which are key determinants of global health. The spread of diseases across wide geographic scales has increased through history. Early diseases that spread from Asia to Europe were bubonic plague, influenza of various types, and similar infectious diseases.
The first cholera pandemic (1817–1824), also known as the first Asiatic cholera pandemic or Asiatic cholera, began near the city of Calcutta and spread throughout South Asia and Southeast Asia to the Middle East, Eastern Africa and the Mediterranean coast. While cholera had spread across India many times previously, this outbreak went further; it reached as far as China and the Mediterranean Sea before subsiding. Millions of people died as a result of this pandemic, including approximately 10,000 troops in British service, which attracted European attention. This was the first of several cholera pandemics to sweep through Asia and Europe during the 19th and 20th centuries. This first pandemic spread over an unprecedented range of territory, affecting almost every country in Asia.
The third cholera pandemic (1846–1860) was the third major outbreak of cholera originating in India in the 19th century that reached far beyond its borders, which researchers at University of California, Los Angeles (UCLA) believe may have started as early as 1837 and lasted until 1863. In the Russian Empire, more than one million people died of cholera. In 1853–1854, the epidemic in London claimed over 10,000 lives, and there were 23,000 deaths for all of Great Britain. This pandemic was considered to have the highest fatalities of the 19th-century epidemics.
The fourth cholera pandemic of the 19th century began in the Ganges Delta of the Bengal region and traveled with Muslim pilgrims to Mecca. In its first year, the epidemic claimed 30,000 of 90,000 pilgrims. Cholera spread throughout the Middle East and was carried to the Russian Empire, Europe, Africa, and North America, in each case spreading via travelers from port cities and along inland waterways.
The fifth cholera pandemic (1881–1896) was the fifth major international outbreak of cholera in the 19th century. The endemic origin of the pandemic, as had its predecessors, was in the Ganges Delta in West Bengal. While the Vibrio cholerae bacteria had not been able to spread to western Europe until the 19th century, faster and improved modes of modern transportation, such as steamships and railways, reduced the duration of the journey considerably and facilitated the transmission of cholera and other infectious diseases. During the fourth 1863–1875 cholera pandemic, the third International Sanitary Conference convened in 1866 in Constantinople had identified religious pilgrimages to be "the most powerful of all causes" of cholera and again Hindu and Muslim pilgrimages were an important factor in the spread of the disease.
The seventh cholera pandemic is the seventh major outbreak of cholera beginning in 1961 and continuing to the present. Cholera has become endemic in many countries. In 2017, WHO announced a global strategy aiming to end the pandemic by 2030.
The Broad Street cholera outbreak was a severe outbreak of cholera that occurred in 1854 near Broad Street in Soho, London, England, and occurred during the 1846–1860 cholera pandemic happening worldwide. This outbreak, which killed 616 people, is best known for the physician John Snow's study of its causes and his hypothesis that germ-contaminated water was the source of cholera, rather than particles in the air. This discovery came to influence public health and the construction of improved sanitation facilities beginning in the mid-19th century. Later, the term "focus of infection" started to be used to describe sites, such as the Broad Street pump, in which conditions are favourable for transmission of an infection. Snow's endeavour to find the cause of the transmission of cholera caused him to unknowingly create a double-blind experiment.
Although a variety of infectious diseases existed in the Americas in pre-Columbian times, the limited size of the populations, smaller number of domesticated animals with zoonotic diseases, and limited interactions between those populations hampered the transmission of communicable diseases. One notable infectious disease that may be of American origin is syphilis. Aside from that, most of the major infectious diseases known today originated in the Old World. The American era of limited infectious disease ended with the arrival of Europeans in the Americas and the Columbian exchange of microorganisms, including those that cause human diseases. Afro-Eurasian infections and epidemics had major effects on Native American life in the colonial period and nineteenth century, especially.
The 2010s Haiti cholera outbreak was the first modern large-scale outbreak of cholera—a disease once considered beaten back largely due to the invention of modern sanitation. The disease was reintroduced to Haiti in October 2010, not long after the disastrous earthquake earlier that year, and since then cholera has spread across the country and become endemic, causing high levels of both morbidity and mortality. Nearly 800,000 Haitians have been infected by cholera, and more than 9,000 have died, according to the United Nations (UN). Cholera transmission in Haiti today is largely a function of eradication efforts including WASH, education, oral vaccination, and climate variability. Early efforts were made to cover up the source of the epidemic, but thanks largely to the investigations of journalist Jonathan M. Katz and epidemiologist Renaud Piarroux, it is widely believed to be the result of contamination by infected United Nations peacekeepers deployed from Nepal. In terms of total infections, the outbreak has since been surpassed by the war-fueled 2016–2021 Yemen cholera outbreak, although the Haiti outbreak is still one of the most deadly modern outbreaks. After a three-year hiatus, new cholera cases reappeared in October 2022.
Seven cholera pandemics have occurred in the past 200 years, with the first pandemic originating in India in 1817. The seventh cholera pandemic is officially a current pandemic and has been ongoing since 1961, according to a World Health Organization factsheet in March 2022. Additionally, there have been many documented major local cholera outbreaks, such as a 1991–1994 outbreak in South America and, more recently, the 2016–2021 Yemen cholera outbreak.
The cholera epidemics in Spain were a series of morbid cholera outbreaks that occurred from the first third of the 19th century until the end of the same century in the large cities of Spain. In total, some 800,000 people died during the four pandemics that occurred in Spain during that century. However, cholera was one of several contagious diseases that struck the country. Suffice it to say that the Spanish population in 1800 was 11.5 million people and was characterized by a high birth and death rate. The successive pandemics that the country suffered caused an economic recession, as well as an opportunity for profound change in health and hygiene in Spain. It was not free of controversy, both for the use of the vaccines created by Jaime Ferrán y Clúa and for the ways of combating the disease, as well as for the policies used to deal with it. It is worth mentioning that the terror caused in the population, due to the deaths caused, was the cause of popular revolts and social instability.
{{cite book}}: CS1 maint: date and year (link)On a Sunday in July 1832, a fearful and somber crowd of New Yorkers gathered in City Hall Park for more bad news. The epidemic of cholera, cause unknown and prognosis dire, had reached its peak.
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