Cholera Disease: A Global Threat and Its Impact (ppt & pdf)

Cholera is a severe diarrheal infection caused by the bacterium Vibrio cholerae, typically transmitted through contaminated food or water. The disease is characterized by acute diarrhea, leading to rapid dehydration and electrolyte imbalance, and is a significant global health threat. Vibrio cholerae has several serogroups, but only O1 and O139 are known to cause outbreaks, with the O1 serogroup being the most prevalent in recent outbreaks. This serogroup is further subdivided into the classical and El Tor biotypes. Each of these contains the Inaba, Ogawa, and Hikojima serotypes.

The bacterium is gram-negative, comma-shaped, with a polar flagellum, and is a facultative anaerobe that thrives in environments with NaCl and a pH range of 6-10 at temperatures between 18-37ºC. Cholera is transmitted primarily by ingesting fecal-contaminated water and food. the pathogen resists gastric acid, allowing it to colonize the small intestine.

Preventive measures include drinking safe water, practicing good hand hygiene, and eating well-cooked food. On a larger scale, ensuring access to clean water and proper sanitation is critical to controlling cholera outbreaks.

Since 1817, there have been seven cholera pandemics. The seventh pandemic, caused by the El Tor biotype, originated in Indonesia in 1961 and affected more countries and continents than any previous outbreak. In 1992, a new serogroup O139 emerged in Madras, India, leading to a cholera epidemic considered by some experts to be an eighth pandemic.

Recent major cholera outbreaks include those in Haiti and Yemen, with the latter experiencing the worst outbreak in the world, as reported by the WHO in October 2016. The incidence of cholera has significantly decreased in many regions due to improved sanitation and healthcare, but it remains a significant public health challenge, especially in developing countries. The increasing antimicrobial resistance of Vibrio cholerae is a growing concern for the future control of cholera outbreaks.
Reference:
https://sciencecodons.com/2793-cholera-disease/

1. 1 Cholera Disease : A Global Threat and Its Impact

2. Introduction Cholera is: An acute diarrheal infection caused by ingestion of food or water contaminated with  Vibrio cholerae The most important symptom is acute diarrhea with severe dehydration and electrolyte imbalance A global threat to public health An indicator of inequity and lack of social development 1.3-4.0 million cases & 21000 - 143000 deaths every year worldwide Cholera is an endemic diarrheal disease in Iran 2

3. Introduction There are many serogroups of  V. cholerae Only 2 serogroups O1, O139 cause outbreaks There is no difference in illness caused by 2 serogroups V. cholerae  O1 has caused all recent outbreaks Pathogenic organisms in O1 serogroup have caused the majority of cholera outbreaks O1 serogroup is subdivided into 2 biotypes : classical & El Tor These 2 biotypes each contain 3 serotypes based on their biochemical properties: Inaba, Ogawa, Hikojima V. cholerae  O139: First identified in Bangladesh in 1992 Caused outbreaks in the past, but recently only in sporadic It has never been identified outside Asia 3

4. 4 Serogroup Biotype Serotype

5. V. cholerae morphology Gram Negative Comma Shape Sheathed, polar flagellum 1.4-2.6µm x 0.5-3µm 5

6. Cholera Physiology Facultative anaerobic Growth stimulated by NaCl pH 6 - 10, Acid labile Temperature 18 - 37ºC 6

7. Cholera Transmission 7

8. Pathogenicity 8

9. Symptoms 9 The most important symptom is: Severe acute diarrhea Severe dehydration & electrolyte imbalance Causes a high mortality

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11. Diagnosis Cultivation S erotyping of microorganisms through agglutination B iochemical and biological methods T oxin assay Enzyme-Linked Immunosorbent Assay (ELISA) I mmunofluorescence assay In Iran (according to WHO) : Microscopic: direct slide observation Sample transportation: Cary-Blair medium Cultivation: Thiosulphate-Citrate-bile Salt-Sucrose agar 11

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13. Provision of safe drinking water Sanitary disposal of human feces Environmental management 13 The best way to prevent

14. Epidemiology 14

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16. the worst cholera outbreak in the world WHO called it: In October 2016, an outbreak of cholera began in war-ravaged  Yemen Recent major outbreaks are: 2010s Haiti cholera outbreak   2016–2021 Yemen cholera outbreak In 2019, 93% of the reported 923,037 cholera cases were from  Yemen  with 1911 deaths 16 Epidemiology

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20. Cholera History in Iran 20

21. 21 Cholera in Iran

22. Present situation of Cholera in Iran 22 Primary health care coverage reported de creased rate of cholera within last decade They provided some of the sanitary services such as safe drinking water in our region But we are still facing with some local epidemics that occasionally spread to many parts of Iran Periodic outbreaks of cholera have been reported from Sistan and Baluchistan and other provinces in the southeast of Iran Most of these outbreaks are linked to cross-border movement of populations

23. Cholera incidence during 1965-2014: A tremendous decrease in incidence Trends from 19.7/100,000 in 1965 to 0.01/100,000 in 2014 With 9 epidemics occurred at 5-6 year intervals The highest incidence was in 1970 at 66.7/100,000 population 23

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25. The most common risk factors C ontaminated water sources Heavy rainfall & flooding P opulation dislocation Most of cholera outbreaks: In warm months from July to November Mostly in rural parts of Sistan and Balouchestan & Kerman areas 25

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27. Increasing of antimicrobial resistance will be a challenge in control of cholera outbreaks in future Immigrants from neighboring countries plays a key role in cholera outbreaks of Iran Cholera is a preventable & treatable infectious disease that still has remained a significant threat to public health particularly in developing countries of Asia & Africa This disease is a key indicator of social development T he risk is highest in areas where basic infrastructure is not available 27 Conclusion

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29. Thanks for your attention! 29

30. Refrences Masoumi -Asl H, Kolifarhood G, Gouya MM. The epidemiology of cholera in the Islamic Republic of Iran, 1965-2014. East Mediterr Health J. 2019;25. Masoumi -Asl H, Gouya MM, Rahbar M, Sabourian R. The epidemiology and antimicrobial resistance of cholera cases in Iran during 2013. Iranian journal of microbiology. 2016 Aug;8(4):232. Babaei Z, Bahrami N. The prevalence of Vibrio Cholera Infection among Patients with Diarrheal Infections in flood affected population of Pol-e Dokhtar County: 2019. Archives of Medical Laboratory Sciences.;5(2):1-3. Awofeso N, Aldbak K. Cholera, migration, and global health–a critical review. International Journal of Travel Medicine and Global Health. 2018 Sep 25;6(3):92-9. Mafi M, Goya MM, Hajia M. A five-year study on the epidemiological approaches to cholera in Iran. Caspian journal of internal medicine. 2016;7(3):162. 30