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Background on Cholera and Bacterium Vibrio cholerae
Information for the general public is covered on the CDC website, in addition to what is already available on Wikipedia. The 2004 review by Sack et al. covers topics relevant to this project in more detail, specifically, treatment with antibiotics and developing resistance, virulence factors, ecology, and vaccines. I briefly discuss these sections of the review below:

Antibiotic Resistance: Antibiotic resistance in cholera was unheard of prior to 1977. The conjugation of plasmids conferring resistance led to the first outbreaks of cholera in Tanzania and Bangladesh, however over the last two decades many countries with endemic cholera have reported the emergence resistant strains. O1 and O139 strains do not typically develop resistance but fluctuating spatial and temporal patterns of resistance suggest inappropriate use of antibiotics leading to emergence of antibiotic resistant strains. Additionally, newly identified genetic elements called integrons may be larger factors in the dissemination of antibiotic resistance.

Virulence Factors: Virulence factors are clusters of genes encoding for products that aid V. cholerae in colonization. These gene clusters can disperse laterally and be transferred to different strains. There are two common virulence factors of pathogenic V. cholerae. CTX, the genome of a lysogenic bacteriophage, can be present in the bacterium as a plasmid or prophage and encodes for a cholera toxin. Vibrio pathogenicity island (VPI) codes for a pilus colonization factor (TCP), promoting interactions between bacteria and attachment to the intestinal brush border. The presence of an integrase in VPI suggests that this virulence factor originated from a bacteriophage and has since been incorporated into the genome of pathogenic strains. Emergence of epidemic strains is often the result of horizontal transfer of these two gene regions.

Ecology: Recent studies show that existence and proliferation of V. cholerae can exist outside of the human body and is common in brackish surface waters, alongside zooplankton and phytoplankton. However, to become a pathogenic these strains must acquire the VPI and then become lysogenized by bacteriophage CTXΦ

Vaccines: Vaccination for cholera has been around since 1880. However, this killed, whole-cell injectable vaccine was associated with severe side effects and was not very effective. Although it is still available today, it is not recommended. Two new oral vaccines are available that confer antibacterial and antitoxicity immunity, however effectiveness is not 100%. Because these vaccines are killed, there is no risk of "leaking", but live vaccines are currently being developed for use in the future. This review does not make any mention towards the implication of leaky vaccine resistance.

Evolmed editor (talk) 03:08, 1 March 2016 (UTC)

Virulence and Antibiotic Resistance of Cholera
Cholera is a water-borne virus that inserts itself into the intestinal epithelium of human hosts. Once embedded in the tissue it secretes CT (cholera toxin) which impedes the regulation of ion concentrations in normal intestinal cells. This is what causes the symptom of diarrhea. According to this article, it is the combination of two factors that are responsible for the lethal effects of the cholera virus in humans: the secretion of CT and the expression of a group of "virulence factors". The article discusses in detail each of the "virulence factors" expressed by genes found in two "clusters" on the cholera viral chromosome. The general function of these factors is for successful colonization of the host. These virulence factors are highly regulated and responsive to changes in the host environment, lending to rapid evolution of the viral genome. Thus, the cholera virus is successful in infecting a host first by establishing colonies in the intestinal epithelium (virulence factors) which then allows for CT secretion. The article also talks about the epidemiology of cholera. Outbreaks occur seasonally, similar to the flu, and is most common in East Asian, African, and Latin American populations. The author gives a history of cholera pandemics. The rapid evolution of antibiotic resistant strains of cholera are concluded to be the cause of these mass outbreaks.

[1]

Jump up ^ "Epidemiology, Genetics, and Ecology of ToxigenicVibrio Cholerae." MMBR 62.4 (1998): n. pag. Epidemiology, Genetics, and Ecology of ToxigenicVibrio Cholerae. Microbiology and Molecular Biology Reviews. Web. 25 Feb. 2016. . Kateyfawcett (talk) 02:22, 1 March 2016 (UTC)Katey FawcettKateyfawcett (talk) 02:22, 1 March 2016 (UTC)

Evolution of Cholera--Physical level: how it transfers between countries and person to person, and the mechanisms of this through time
Mechanisms of how cholera evolved: multiple horizontal gene transfers and antigenic change. Also discusses the location where metamorphosis of cholera occurs; both in it's own genome and where the virus physically was (infection in the intestine).
 * http://www.ncbi.nlm.nih.gov/pmc/articles/PMC155710/

Analyzes the driving forces behind horizontal transfer of cholera. Highlights the effect of the virus' aquatic environment on conservation.
 * http://femsle.oxfordjournals.org/content/322/1/68

Discusses in depth the major (6) pandemics of the disease through the years and how it spread from each place. Also discusses the current 7th pandemic, and the more recent outbreaks. The article highlights the variance of strains is a result of horizontal gene transfer/antibiotic resistance, and is transmitted fecal-oral.
 * http://www.britannica.com/science/cholera

Brennamarielies (talk) 03:29, 1 March 2016 (UTC)

Background Information and Information on Current Wikipedia Page
Topics already on page- basic description, signs and symptoms, cause (susceptibility, transmission), mechanism, diagnosis, prevention (surveillance, vaccine, sari filtration), treatment (fluids, electrolytes, antibiotics, zinc), prognosis, epidemiology, history and research, society and culture, notable cases The mechanisms that the current page covers include the bacteria's physiological interaction with the host small intestine, leading to the described symptoms. There is also a short section on the genetic structure, which varies between cluster I (1960s - 1970s strains) and cluster II (1980s - 1990s strains). The prevention sections focuses on methods such as sanitation, sterilization, and water purification. There is information on the oral vaccine, however it is not recommended by the CDC to US travelers, and the less effective injection vaccine. The epidemiological information states that it occurs mainly in the developing world and although the biological mechanism is known, the reasons why outbreaks happen in certain areas is not known. Link: https://en.wikipedia.org/wiki/Cholera

Vibrio Cholerae specific page - This page discusses bacteria characteristics and pathogenesis, bacteriophage CTXphi, and diversity and evolution relating to the two serogroups (O1 and O139) and biotypes of O1 (classical and El Tor). There is also more detailed information on the genome. Link: https://en.wikipedia.org/wiki/Vibrio_cholerae

Topics not on Wikipedia- Mechanisms of horizontal gene transfer leading to increased virulence and occurrence of pandemics, Association with El Tor and Classical strains, treatment evolution over time

http://www-ncbi-nlm-nih-gov.offcampus.lib.washington.edu/pubmed/22634452 Cholera vaccine that contains Vibrio cholerae O1 AND O139. The vaccine has a 50% protection rate and protects for up to three years.

http://www.ncbi.nlm.nih.gov/pmc/articles/PMC19707/ Harmless strains versus strains that cause outbreaks. Describes genetic difference between the two and the identification of chromosomal pathogenicity island (PAI) that may be transferred between V. cholerae to lead to epidemic/pandemic causing versions of the pathogen. Turtle1229 (talk) 03:52, 1 March 2016 (UTC)

Modern and Outdated Treatments
- http://www.who.int/mediacentre/factsheets/fs107/en/ : WHO article describing treatments, prevention methods, symptoms. Recommends against mass antibiotic administration due to risk of developing antibiotic resistant strains in a community. Treatment includes immediate oral administration of salty and sugary fluids, preferably rice-based for better effectiveness. 1337Dennis (talk) 02:42, 1 March 2016 (UTC)

- http://www.ncbi.nlm.nih.gov/pubmed/24944120 : Antibiotics mostly reduce the amount of time an individual has diarrhea from cholera by 1.5 days. 1337Dennis (talk) 02:42, 1 March 2016 (UTC)

- https://www.youtube.com/watch?v=jG1VNSCsP5Q : helpful educational story that visualizes sources, transmission, prevention and treatment of cholera. Specifies oral administration of 1/2 a teaspoon of salt and 6 teaspoons of sugar in 1 L of water to cholera sufferers. Also depicts sanitization of water using chlorine or boiling. 1337Dennis (talk) 02:42, 1 March 2016 (UTC)

Medical History of Cholera
Prior to the discovery of the cause of cholera there was an eclectic range of treatments utilized. Common medical treatments of the 19th century epidemics and pandemics included bleeding or blood letting, plugging of the anus to prevent fluid flow, enemas, medication with opium, castor oil, calomel, or alcohol, dietary regimes, and "gut washing". Many homeopathic treatments and religious intervention rituals were also commonly seen.
 * "Cholera Epidemics in the 19th Century." Open Collections Program: Contagion,. Harvard University Library, n.d. Web. 29 Feb. 2016. .
 * Claeson, Marium. "Cholera | Pathology." Encyclopedia Britannica Online. Encyclopedia Britannica, n.d. Web. 29 Feb. 2016. .

This book discusses the development of the cholera vaccination. The development began with Pasteur's discoveries of Germ Theory, pointing to pathogens as the cause of disease and infection. By the 1880's 2 scientists, Koch and Pacicni, had separately identified the virus as the cause of the cholera. Soon after the discovery of resistance to pathogens in animals was then discovered, which lead to the development of "serum treatment". Cholera was often treated this way, by injecting the patient with the "resistant serum" from and animal giving the patient acquired immunity. We have since developed modern day vaccination to treat cholera.
 * Porter, Roy. Blood and Guts: A Short History of Medicine. New York: W.W. Norton, 2003. 80-100. Web. 29 Feb. 2016. .

The most common tool for treatment/management of Cholera today is Oral Re-hydration Therapy. This was developed and put into widespread use in the 1960's. Prior, the treatment was often attempted but failed due to lack of knowledge of the "physiological requirements of sodium-glucose transport". Many physicians would inject pure water into the patient, causing disruption of the blood chemistry.
 * Harris, Jason B., Firdausi Qadri, Edward T. Ryan, and Stephen B. Calderwood. "Cholera." The Lancet 379.9835 (2012): 2466-476. The Lancet. Web. 29 Feb. 2016.

Kateyfawcett (talk) 03:15, 1 March 2016 (UTC)Katey Fawcett

Genetic Determinants of Antibiotic Resistance
V. Cholerae O1 strain has two biotypes, classical and El Tor, the latter of which has evolved increased adaptability to survive in the intestinal epithelium of its human host. Recently, hybrid strains of the classical and El Tor biotypes have been discovered during outbreaks in parts of East Asia. These hybrid strains are more toxigenic then their ancestors, classical and El Tor. One of the two hybrid strains has two types of CTX prophages that have classical rstR and classical ctxB genes that are known to be more toxigenic. The other hybrid strain contains El Tor rstR and classical ctxB genes. The striking characteristic of these strains is that they are shown to be resistant to common antibiotics used to alleviate the symptoms and spread of cholera. By understanding these new resistant strains, scientists can understand the continued mass outbreaks in various countries.

Goel, A. K., Jain, M., Kumar, P., Sarguna, P., Bai, M., Ghosh, N., & Gopalan, N. (2011). Molecular characterization reveals involvement of altered El Tor biotype Vibrio cholerae O1 strains in cholera outbreak at Hyderabad, India.The Journal of Microbiology, 49(2), 280-284.

http://www.nature.com/nature/journal/v467/n7318/edsumm/e101021-13.html: Discussing the history of virulence in V. Cholerae. In this paper a sustainable model for the evolution of virulent strains of cholera.

http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3545932/: Reviewing the genetic and ecological factors of new clones of bacteria. In addition, the major virulent factors are described and how they, along with phages, are involved in horizontal transfer.

http://www.ncbi.nlm.nih.gov/pubmed/19141742: Discusses the emergence of more virulent strains of Cholera, specifically the O1 strain. Genetic sequencing was conducted in order to determine the molecular diversity.

Dmzepeda21 (talk) 08:16, 1 March 2016 (UTC)