Category Archives: cholera

Personal ties to Cholera, 1833

Map created by Henry S Tanner of the 1832 Cholera pandemic

What a strange feeling looking at this map of the 1832 cholera pandemic.  It looks like a blotchy bruise on the country. A little surprise at how restricted the pandemic was in America. As it turns out this map is incomplete, ending in October 1832;  cholera eventually traveled down the Mississippi to reach New Orleans and stops along the way.  One of my first experiences with history of medicine discovered in my own research occurred while doing some family genealogy. Cholera is often depicted among the poor in crowded, old cities like London. For me though, cholera is a disease of the American frontier.

My ancestor John Biggs Moore died of cholera on July 4th, 1833. John Moore was the patriarch of a large family in frontier Illinois on the Mississippi River. He came to Kaskaskia Illinois with his parents in 1781 in the last years of the Revolutionary war. His father James Moore had first seen the Illinois country in the militia of George Rogers Clark when they took the area from English control during the Revolution. John Moore was teenager listed among the men on the first census of Americans in the Illinois country in 1787 used in part to prove that Americans were settled as far west as the Mississippi River to Congress. When American territorial boundaries were established, the Mississippi River was set as the western border, putting them on the furthest edge of the American frontier. (The Louisiana Purchase would extend the frontier in 1804.) The Moore family started the American settlement at Bellefontaine (present city of Waterloo), at the site of a big well-known spring,  on the trail between Kaskaskia and Cahokia in 1782.

John Moore’s death on July 4th tells us something about its circumstances. July 4th was the biggest community celebration held on the frontier. John Moore was the son, son-in-law, and nephew of Revolutionary war soldiers and a former War of 1812 soldier. There is little doubt that he would have been part of the independence day celebrations. Cholera came to Illinois the previous summer with Gen. Scott’s arrival with federal soldiers to take charge of the Black Hawk War.  They arrived at Fort Dearborn (modern Chicago) on the shore of Lake Michigan and the disease traveled with the troops down the Illinois and Mississippi rivers fading out in the fall. When cholera re-emerged the following summer it is recorded in Belleville in July of 1833, claiming the life of former Governor Ninian Edwards on July 20, 1833. John Moore died of it over two weeks earlier 20 miles from Belleville. Most of the men in John Moore’s extended family where in the Illinois militia on campaign under his step-brother Gen. Samuel Whiteside during the Black Hawk War. So the community gathering for independence day celebrations the summer after the war, that could have went on for days, is the context of his death.

The arrival of the first steamship in Illinois brought with it the double-edged sword of connection with ‘civilization’. Most of the early Illinois pioneers did not come with grand visions of living in an isolated primitive wilderness.  They were very focused on land ‘improvements’ and recreating a Virginia-style plantation landscape. Steam ships would have been heralded as a sign of progress since river trade was vital to their economy until the railroad arrived. The cholera brought to the frontier by the federal troops killed more people than the Black Hawk War.

Historic Meanings of “Cholera”

Today the term cholera is restricted to suspected infections caused by Vibrio cholerae, sometimes called Asiatic cholera. Vibrio cholerae produces a very characteristic watery diarrhea sometimes described as ‘rice water’. This narrow definition wasn’t always so.

Since antiquity, cholera could refer to any diarrhea or dysentery. The term cholera comes from the Greek word cholē meaning bile. Cholera then was a flushing of bile from the body in an attempt to rebalance Galen’s four humors of the body (blood, bile, black bile, and phlegm) [1].

In 19th century American medical records,  it is common to see three types of cholera reported: cholera morbus, cholera infantum, and Asiatic cholera. Cholera morbus and cholera infantum were both terms for non-specific diarrhea and/or dysentery in adults and children under age five respectively.  Cholera morbus was sometimes called the summer complaint and was usually found in older children and adults from July to September [2]. It was caused by a variety of gastrointestinal pathogens with a significant contribution from contaminated food. Cholera infantum was given as the primary cause of death in children under age five in 19th century Illinois [2]. Physicians specifically associated it with the ages of teething and finger foods. Even given its non-specific definition, it was still probably over diagnosed due to paradigms of childhood illness. For example, early Illinois physicians  did not believe that children could contract malaria, then endemic in Illinois. Asiatic cholera is caused by Vibrio cholerae, epidemic in Illinois in 1832-1834, 1838, 1849-1852, 1866-1867, and 1892 [2]. Apart from discrete epidemic waves, Asiatic cholera was uncommon in America.


[1] Männikkö, N. (Ed) (2011). Etymologia: Cholera. Emerging Infectious Disease, 17 (11)

[2]  Rawlings, Issac D. et al. (1927).The Rise and Fall of Disease in Illinois. State Department of Health.

Cradle of Cholera’s Seventh Pandemic Found

Cholera is a disease of seemingly endless fascination to epidemiologists for good reason. Vibrio cholerae emerged on a global stage in the 19th century just in time for the beginnings of modern medicine to grapple with it and for its transmission to prove the worth of epidemiological work. Although we understand its treatment and transmission well, it is still endemic in several regions, resulting in 3-5 million reported cases per year.

Like other relatively recently emerged pathogens, cholera has come in distinctive waves. Six discrete pandemics occurred between 1817 and 1923, it is believed from what is now known as the classic biotype. From 1923 to 1961 no pandemics occurred but evolution was far from standing still.  The seventh pandemic became apparent in the 1960s as the less severe El Tor biotype, that emerged sometime between 1827 and 1936, began to rapidly spread. The El Tor biotype transmits and survives better in the environment and human host than the classical biotype, including producing more asymptomatic and less severe infections.  El Tor represents an evolutionary leap forward for Vibrio cholerae on every level. We are still in the seventh pandemic. Preliminary characterization of the El Tor biotype’s mobile genetic units revealed too much diversity to reconstruct the pandemic.

Taking advantage of modern complete genome sequences, Mutreja et al (2011) collected and compared the complete genomic sequences of 136 isolates of the El Tor biotype collected over the last 40 years of the seventh pandemic plus 18 previously published genomes of El Tor and Classical biotypes. They were able to track three independent overlapping waves of cholera that are all descended from a 1950s ancestor in the Bay of Bengal. Each of these three descendant lineages left the Bay of Bengal independently for a transcontinental run.

Inferred transmission of the seventh cholera pandemic based on phylology. (Source: Mutreja et al, 2011, doi:10.1038/nature10392) Click to enlarge.

Each of the three waves can be distinguished genetically. The waves can be differentiated by the distinctive version of cholera toxin prophage carried by each clade. In addition, the first wave lacks the antibiotic cluster SXT/R391 and has obtained two VSP-2 genes. The acquisition of the SXT/R391 integrative and conjugative element (ICE) distinguishes the second wave beginning in 1978-1984. O139 strains of cholera are descended from the  second wave clone close to common ancestor of wave 1 and wave 2. The lineages within each wave have become quite complex but remain local enough not to produce waves of their own.

Each of the three waves reflects a clade of cholera that emerged from the Bay of Bengal and spread around the world, evolved into local lineages but then subsequently went extinct in non-endemic areas. Four discernible long distance transmissions have happened with the current outbreak in Haiti being the most recent. The overlapping nature and common source of these distinct waves reinforces the importance of the Bay of Bengal as cholera’s evolutionary cradle.

Considering the importance the Bay of Bengal for cholera, could other pathogens like Yersinia pestis, that has produced similar overlapping pandemic waves, also have an evolutionary cradle?  If so, then a sentinel  system set up around the cradle could give us crucial warning of an oncoming pandemic. The Bay of Bengal also serves as a lesson that knowing of the cradle is a far cry from controlling it.

Mutreja, A., Kim, D., Thomson, N., Connor, T., Lee, J., Kariuki, S., Croucher, N., Choi, S., Harris, S., Lebens, M., Niyogi, S., Kim, E., Ramamurthy, T., Chun, J., Wood, J., Clemens, J., Czerkinsky, C., Nair, G., Holmgren, J., Parkhill, J., & Dougan, G. Evidence for several waves of global transmission in the seventh cholera pandemic. (2011). Nature DOI: 10.1038/nature10392

Safa, A., Nair, G., & Kong, R. (2010). Evolution of new variants of Vibrio cholerae O1 Trends in Microbiology, 18 (1), 46-54 DOI: 10.1016/j.tim.2009.10.003