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CHOLERA—Population, Environmental, and Behavioral Factors

CHOLERA—Population, Environmental, and Behavioral Factors. Peter Ntiamoah Walden University, School of Public Health PUBH-6165-2 ENVIRONMENTAL HEALTH. BACKGOUND. During the 19 th century, cholera spread from Ganges delta in India to the rest of the world 6 pandemics were recorded

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CHOLERA—Population, Environmental, and Behavioral Factors

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  1. CHOLERA—Population, Environmental, and Behavioral Factors Peter Ntiamoah Walden University, School of Public Health PUBH-6165-2 ENVIRONMENTAL HEALTH

  2. BACKGOUND • During the 19th century, cholera spread from Ganges delta in India to the rest of the world • 6 pandemics were recorded • Millions of people were killed across Europe, Africa, and the Americas • The 7th pandemic started in 1961 in South Asia and has been registered in 163 countries • Source:World Health Organization. Cholera Fact Sheet No. 107.

  3. BACKGOUND—continued • The spread and dynamics of cholera morbidity has their specific feature in each continent • In Asia, the epidemic process is manifested as permanent morbidity • Africa determines the total morbidity level in the 7th pandemic • Both Europe and America have imported cholera Reference: Mukharskaiia, L., Kariakova, L., Khaitovich, A., 2004. Cholera prevalence worldwide and in Ukraine. ZH Mikrobiol Epidemiol Immunobiol, (1):93-6

  4. DISTRIBUTION AND INCIDENCE • As of 2000, the spread of cholera were as follows: • Africa 27 countries • Asia 13 countries • Latin America 9 countries • Europe 2 countries • Oceania 4 countries • Approximately 79 million people are estimated to be at risk in Africa (UN) • The crude case fatality rate since the cholera outbreak in Zimbabwe is 4.3% (WHO) Source: World Health Organization, 2000. Water Related Diseases United Nations. Cholera. Accessed on November 7, 2009 from http://cyberschoolbus.un.org/special/health/disease/cholera.htm

  5. DISTRIBUTION AND INCIDENCE—continued • Cholera is a major problem in Africa and Asia • In the year 2000, • 140,000 cases were reported to WHO • 5,000 deaths resulted from cholera • Africa accounted for 87% of the above cases and deaths • In 2006, • More than 6,000 deaths resulted from cholera, worldwide • About 90% of these deaths were from Africa • From August 2008 to May 2009, • Cholera infected more than 97,000 people in Zimbabwe, and killed more than 4000 people. References: World Health Organization, 2000. Water Related Diseases World Health Organization, 2009. WHO stresses on proper sanitation to combat cholera

  6. INTRODUCTION • Cholera is an acute, infectious gastroenteritis, caused by Gram-negative enterotoxin-producing strains of the bacterium Vibrio cholerae (CDC). • The enterotoxin affects the mucosal epithelium lining of the small intestine leading to an exhaustive diarrhea. Reference: Centers for Disease Control and prevention. Cholera.

  7. INTRODUCTION—continued • The enterotoxin interacts with the epithelium lining of the small intestines to pump chloride ions into the small intestine. • This creates ionic pressure which blocks sodium ions from entering the cell • The osmotic pressure can pull up to six liters of water per day through the intestinal cells creating the massive amounts of diarrhea (Mayol, 1998; Lucas, 2008). • Reference: • Lucas, M., 2008. Enterocyte chloride and water secretion into the small intestine after enterotoxin challenge: unifying hypothesis or intellectual dead end? J Physiol Biochem, 64(1):69-88 • Mayol, J., Fernandez-Represa, J., 1998. Chloride secretion in the intestinal epithelium: channels, ions, and intracellular signaling. Rev. Esp. Enferm Dig, 90(10):714-21

  8. SYMPTOMS OF CHOLERA • The infection is often mild or without symptoms, but sometimes it can be severe. • Approximately one in 20 infected persons has severe disease characterized by • profuse watery diarrhea • vomiting, and leg cramps. • Low blood pressure—hypotensive • Watery stool and shock (4-12 hours of infection) • Dehydration • Incubation Period: 2 hours to 5 days • Without treatment, death can occur within hours (CDC, WHO). • Reference: • Centers of Disease Control and Prevention. Cholera. • World Health Organization. Cholera.

  9. SEROGROUPS • Based on the somatic O antigen, vibrio cholerae species can be divided into two major groups: • O1 • Ogawa (VCO) and Inaba (VCI) • O139 serotypes • All other serotypes are referred to as non-O1 • Cholera is typically associated with the O1 and the O139 serotypes • Reference • Stroeher, U.,Karageorgos, L., Morona, R., Manning, P., 1992. Serotype conversion in Vibrio cholerae O1. Proc Natl Acad Sci U S A. ; 89(7): 2566–2570.

  10. PATHWAY • Fecal-Oral route • Drinking water or eating food contaminated with the cholera bacterium • Sources: • Feces from an infected person • Inadequate treatment of sewage and drinking water • Eating raw or undercooked shellfish from brackish rivers or coastal waters eg. Gulf of Mexico • Reference: • World Health Organization • Miller, C., Feachem, R., Drasar, B., 1985. Cholera epidemiology in developed and developing countries: new thoughts on transmission, seasonality and control. Lancet ii, 261-3

  11. OUTBREAK FACTORS • Population • Sanitation • Demographics • Habitat • Environment and geographical location • Aquatic • Climatic Change • Culture • Socioeconomic constraints • Individual Psychology • Source of water consumption Reference: • Meade, M., 1977. Medical geography as human ecology: The dimension of population movement. The Geographical Review, 67(4), 379-393.

  12. Environmental Factors • V. cholerae (O1 and O139) inhabit in seas, estuaries, brackish waters, rivers, and ponds of coastal areas of the tropical world (Africa) due to presence of: • Sunlight • Higher temperature • Humidity due to evaporation • Salinity • Phytoplankton References: • Emch, M., Feldacker, C., Islam, M., Ali, M., 2008. Seasonality of cholera from 1974 to 2005: A review of global patterns • Huq, A., Colwel, R., 1996. Environmental factors associated with emergence of disease with special reference to cholera. Eastern Mediterranean Health Journal, Vol. 2, Issue 1, p. 37-45.

  13. Environmental Factors—cont. • Climate Variability (Islam, 1994; Alam, 2006; Lipp, 2002; Sack, 2003). • Sustained temperatures, high above normal in two consecutive seasons, followed by a slight cooling in the second season, trigger an outbreak of a cholera epidemic (Olago, 2007). References: Alam, M., Hasan, N., Sadique, A., Bhuiyan, N., Ahmed, K., et al., 2006. Seasonal cholera caused by Vibrio cholerae serogroups O1 and O139 in the coastal aquatic environment of Bangladesh. Appl Environ Microbiol, 72(6):4096-4104 Islam, M., Drasar, B., Sack, R., 1994. Probable Role of Blue-Green-Algae in Maintaining Endemicity and Seasonality of Cholera in Bangladesh – a Hypothesis. Journal of Diarrhoeal DiseasesResearch, 12(4):245-256. Lipp, E., Huq, A., Colwell, R., 2002. Effects of global climate on infectious disease: the cholera model. Clinical Microbiology Reviews 2002, 15(4):757 Olago, D., Marshall, M., Wandiga, S., Opondo, M., Yanda, P., et al., 2007. Climatic, Socio-economic, and Health Factors Affecting Human Vulnerability to Cholera in the Lake Victoria Basin, East Africa.

  14. Environmental Factors—cont. • Upper troposphere humidity • Cloud cover • Periodic effects of ENSO • Warm El Niño • Reference: Epstein, P. 1998. Health Applications of Remote Sensing and Climate Modeling.People and pixels: Linking remote sensing and social science

  15. Population Factors—Sanitation • Lack of clean water, inadequate sanitation management, and suboptimal food-handling practices (Kur et al, 2009) • Poor hand-washing practices and bad eating habits in Africa (Masereka, 2009) • References: Kur, L., Mounir, C., Lagu, J., Muita, M., Rumunu, J., et al, 2009. Cholera Outbreak—Southern Sudan, 2007. MMWR, 4/10/2009.Vol. 58, issue 13, pp. 337-341 Masereka, B., 2009. Uganda, Kases: Unwashed hands cause cholera. New Vision. http://sanitationupdates.wordpress.com/2009/10/07/uganda-kasese-unwashed-hands-cause-cholera

  16. Population Factors—Sanitation • Residential Sanitation In Africa includes • Flush or pour-flush to elsewhere • Pit latrine without slab or open pit • Bucket • Hanging toilet or hanging latrine • No facilities or bush or field (open defecation) • Source: WHO/UNCEF, 2006. A Snapshot of Drinking Water and Sanitation in Africa

  17. Population Factors—Waste Management • Waste management facilities are not available in most African countries • Effluent solid and liquid wastes are released to the environment without treatment (Onibokun, 2006; Boadi, 2003) • Uncontrolled garbage problems in African cities • Open landfills • Refuse disposal into streams, surface drains, and canals. • References: Boadi, K., Kuitenen, 2003. Municipal Solid Waste Management in Accra Metropolitan Area, Ghana. The Environmentalist, Vol. 23, Number 3. Onibokun, A., Kumuyi, A., 2006. Governance and Waste Management in Africa.

  18. Cultural Factors—Food and Water • Presence of street food vendors in many cities • Consumption of raw foodstuffs • Limited or lack of governmental regulations and enforcement (WHO) • Food from the street are often open and exposed to flies References: • WHO/UNCEF, 2006. A Snapshot of Drinking Water and Sanitation in Africa

  19. Cultural Factors—Food and Water • Drinking water sources in developing countries: • Unprotected dug well • Unprotected spring and streams • Small cart with tank/drum • Tanker truck • Surface water (river, dam, lake, pond, stream, channel, irrigation channel) • Source: WHO/UNCEF, 2006. A Snapshot of Drinking Water and Sanitation in Africa

  20. Cultural Factors-Socioeconomic l • Abject poverty in developing countries • Lack of education concerning the disease • Obligation to shake hands • Culture of eating together with fingers (from same bowl)

  21. EFFECTS OF FLIES ON CHOLERA • Houseflies (Musca domestica) can disseminate Vibro cholerae—spreading the bacterium from infected feces / foods to foods (Fotedar, 2001) • Wings of houseflies serve as mechanical transmission device for Vibro cholerae (Yap, 2008) • Cholera microbes survived on the external surface of flies for 5 to 7 days, and in the insect organism (Kotenok, 1977). • References: Fotedar, R., 2001. Vector potential of houseflies (Musca domestica) in the transmission of Vibrio cholerae in India. Acta Trop., 78(1): 31-4. Kotenok, I., Chicherin, I., 1977. Houseflies (M. domestica L.) as transmitters of the agent of cholera. Zh Mikrobiol Epidemiol Immunobiol., (12):23-7

  22. EFFECTS OF FLIES ON CHOLERA—continued • Flies liquefy food by regurgitating digestive juices, stomach contents and enzymes onto food before ingestion. • The pathogens are then deposited when the fly crawls on food or in the fly excrement (Kalpana, 2008). • Reference: Yap, K., Kalpana, M., Lee, H., 2008. Wings of the common house fly (Musca domestica L.): importance in mechanical transmission of Vibrio cholerae. Trop. Biomed.,25(1):1-8.

  23. PREVENTION • Concerted efforts are needed from • World Health Organization • United Nations • Centers for Disease Control and Prevention • Local Governments • General public • Work together to • control sanitation and waste management • Improve hygiene • Provide food safety • Improve on the quality of drinking water • Provide • Keep track on any climatic change • Provide better assurance in times of an outbreak • Reference: • World Health Organization. Cholera: Prevention and Control

  24. Prevention—WHO • WHO Program on Cholera needs • to obtain better data and ensure greater information sharing • to adopt a coordinated multisectoral approach • to help improve sanitation and sewage disposal in African countries • to ensure political commitment and community involvement

  25. Prevention—United Nations • The Governing Council of the United Nations Environmental Programme (UNEP) must • Strengthened its cholera control measures • Provide sanitary control and personal hygiene workshops to the local government, ministries of health, and the general public • Provide surveillance in disaster areas an refugee camps

  26. Prevention—CDC • Must enhance its international disease surveillance • Work with the local governments to provide better understanding of the disease • Train the locals about disease control and prevention

  27. Prevention—Local Government • Food safety standards must be enacted and regulations must be enforced • Develop better local reporting system and improve communications with UN and WHO. • Improve sanitation management in large cities and towns—no open landfill • Provide safe drinking water the population • Improve the socioeconomic status of the people

  28. Prevention—General Public • Must change their behavior towards the disease • Practice personal hygiene and hand washing • Practice food safety techniques • Control houseflies

  29. Further Readings • For cost-benefit comparisons • Jeuland, M., Whittington, D., 2009. Cost-benefit comparisons of investments in improved water supply and cholera vaccination programs. Vaccine, 27(23):3109-20 • Lundkvist, J., Steffen, R., Jonssen, R., 2009. Cost-benefit of WC/rBS oral cholera vaccine for vaccination against ETEC-caused travelers' diarrhea. J Travel Med 16(1):28-34. • For Treatment • World Health Organization • www. Who.org • Centers for Disease Control and Prevention • www.cdc.gov

  30. QUESTIONS? • Thanks for your audience.

  31. References: • Alam, M., Hasan, N., Sadique, A., Bhuiyan, N., Ahmed, K., et al., 2006. Seasonal cholera caused by Vibrio cholerae serogroups O1 and O139 in the coastal aquatic environment of Bangladesh. Appl Environ Microbiol, 72(6):4096-4104. • Boadi, K., Kuitenen, 2003. Municipal Solid Waste Management in Accra Metropolitan Area, Ghana. The Environmentalist, Vol. 23, Number 3. • Centers for Disease Control and prevention. Cholera. • Colwell, R., Huq, A., 2001. Marine ecosystems and cholera. Hydrobiologia 460:141-145. • Emch, M., Feldacker, C., Islam, M., Ali, M., 2008. Seasonality of cholera from 1974 to 2005: A review of global patterns • Epstein, P. 1998. Health Applications of Remote Sensing and Climate Modeling.People and pixels: Linking remote sensing and social science • Islam, M., Drasar, B., Sack, R., 1994. Probable Role of Blue-Green-Algae in Maintaining Endemicity and Seasonality of Cholera in Bangladesh – a Hypothesis. Journal of Diarrhoeal DiseasesResearch, 12(4):245-256. • Huq, A., Colwel, R., 1996. Environmental factors associated with emergence of disease with special reference to cholera. Eastern Mediterranean Health Journal, Vol. 2, Issue 1, p. 37- 45. • Kur, L., Mounir, C., Lagu, J., Muita, M., Rumunu, J., et al, 2009. Cholera Outbreak—Southern Sudan,2007. MMWR, 4/10/2009.Vol. 58, issue 13, pp. 337-341 • Lipp, E., Huq, A., Colwell, R., 2002. Effects of global climate on infectious disease: the cholera model. Clinical Microbiology Reviews 2002, 15(4):757 • Lucas, M., 2008. Enterocyte chloride and water secretion into the small intestine after enterotoxin challenge: unifying hypothesis or intellectual dead end? J Physiol Biochem, 64(1):69-88 • Mayol, J., Fernandez-Represa, J., 1998. Chloride secretion in the intestinal epithelium: channels, ions, and intracellular signaling. Rev. Esp. Enferm Dig, 90(10):714-21 • Meade, M., 1977. Medical geography as human ecology: The dimension of population movement. The Geographical Review, 67(4), 379-393. • Miller, C., Feachem, R., Drasar, B., 1985. Cholera epidemiology in developed and developing countries: new thoughts on transmission, seasonality and control. Lancet ii, 261-3

  32. Reference—cont. • Mukharskaiia, L., Kariakova, L., Khaitovich, A., 2004. Cholera prevalence worldwide and in Ukraine. ZH Mikrobiol Epidemiol Immunobiol, (1):93-6 • Olago, D., Marshall, M., Wandiga, S., Opondo, M., Yanda, P., et al., 2007. Climatic, Socio- economic, and Health Factors Affecting Human Vulnerability to Cholera in the Lake Victoria Basin, East Africa. • Onibokun, A., Kumuyi, A., 2006. Governance and Waste Management in Africa. • Pascual, M., Dobson, A., 2005. Seasonal patterns of infectious diseases. Plos Medicine, 2(1):18- 20. 14. • Sack, B., Siddique, A., Longini, I., Nizam, A., Yunus, M.,et al., 2003. A 4-year study of the epidemiology of Vibrio cholerae in four rural areas of Bangladesh.Journal of Infectious Diseases 2003, 187(1):96-101 • von Seidlein, L., Wang, X., Macuamule, A., Mondlane, C., Puri1, M., et al, 2008. Is HIV infection associated with an increased risk for cholera? Findings from a case–control study in Mozambique. Tropical Medicine and International Health, Volume 13, Number 5, pp 683–688 • Stroeher, U.,Karageorgos, L., Morona, R., Manning, P., 1992. Serotype conversion in Vibrio cholerae O1. Proc Natl Acad Sci U S A. ; 89(7): 2566–2570. • United Nations. Cholera. Accessed on November 7, 2009 from http://cyberschoolbus.un.org/special/health/disease/cholera.htm • Yap, K., Kalpana, M., Lee, H., 2008. Wings of the common house fly (Musca domestica L.): importance in mechanical transmission of Vibrio cholerae. Trop. Biomed.,25(1):1-8. • World Health Organization. Cholera Fact Sheet No. 107. • World Health Organization, 2000. Water Related Diseases • World Health Organization, 2009. WHO stresses on proper sanitation to combat cholera • WHO/UNCEF, 2006. A Snapshot of Drinking Water and Sanitation in Africa

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