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 spread 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.
An epidemic is the rapid spread of disease to a large number of hosts in a given population within a short period of time. For example, in meningococcal infections, an attack rate in excess of 15 cases per 100,000 people for two consecutive weeks is considered an epidemic.
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.
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.
The Chicago 1885 cholera epidemic myth is a persistent urban legend, stating that 90,000 people in Chicago died of typhoid fever and cholera in 1885. Although the story is widely reported, these deaths did not occur.
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 second cholera pandemic (1826–1837), also known as the Asiatic cholera pandemic, was a cholera pandemic that reached from India across Western Asia to Europe, Great Britain, and the Americas, as well as east to China and Japan. Cholera caused more deaths, more quickly, than any other epidemic disease in the 19th century. The medical community now believes cholera to be exclusively a human disease, spread through many means of travel during the time, and transmitted through warm fecal-contaminated river waters and contaminated foods. During the second pandemic, the scientific community varied in its beliefs about the causes of cholera.
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 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 sixth cholera pandemic (1899–1923) was a major outbreak of cholera beginning in India, where it killed more than 800,000 people, and spreading to the Middle East, North Africa, Eastern Europe, and Russia.
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. Eurasian infections and epidemics had major effects on Native American life in the colonial period and nineteenth century, especially.
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.
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.
Haridwar Kumbh Mela is a mela, associated with Hinduism and held in the city of Haridwar, India held every 12 years. The exact date is determined according to Hindu astrology: the Mela is held when Jupiter is in Aquarius and the Sun enters Aries. The event possesses deep religious significance to Hindus as well as other spiritual seekers. Historically, it was an important commercial event and was attended by merchants from as far as Arabia.
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.
The first major cholera outbreak in Luxembourg was in 1827, with further outbreaks in 1832, 1849, 1854 and 1865. Due to population growth, poverty and poor hygiene conditions, outbreaks were relatively frequent in Luxembourg in the 19th century.
