Presentation on theme: "Cholera Prevention 10 Key factors UNICEF West and Central Africa."— Presentation transcript:
Cholera Prevention 10 Key factors UNICEF West and Central Africa
OBJECTIVE OF NORWAY INITIATIVE Develop systems for cholera prevention and outbreak response and to extend the benefits over a longer time frame to reduce diarrhoeal disease incidence.
1. What are the symptoms? Very rapid onset of vomiting and diarrhoea with large volumes of very watery (rice water type) stools (>3 times a day) Severe de-hydration, = low pulse, undetectable blood pressure, sunken eyes, wrinkled hands and feet Slow recovery of shape after depression of skin No urine output Laboratory confirmation but count all suspected cases and treat
2. How is it transmitted? It is caused by a bacterium (Vibrio cholerae) which lives naturally in brackish/freshwater amoeba, and is transmitted through -: Unsafe water (7/8 investigations in Latin America identified this as a major route) Unwashed fruit and veg (or washed in bad water), left over rice not re-heated (3 investigations +Lusaka 2004), Lack of handwashing (food preparation, hand shaking, childcare) Cooked and uncooked sea food – vibrio survives light cooking (2 investigations)
3. Who is most at risk? Those living near lagoons / low lying areas with fresh/ brackish water/ fishing populations With unsafe water sources With poor faecal disposal practices With poor personal hygiene With poor food hygiene (esp. moist food of neutral acidity) Close to cholera patients in early stages (hyper-infectivity) and dealing with bodies
4. When does cholera become epidemic? After heavy period of rainfall When water temperatures rise When normal diarrhoeal incidence increases Endemic cholera with good sanitation needs permanent source of vibrio, but with poor sanitation higher secondary transmission can maintain endemic status
5. How long does it take? Incubation period 2hrs-5 days Infection 7-14 days, but most people do not become ill or show any symptoms Only about 10-20% of infected people show moderate or severe symptoms. Moderate symptoms difficult to differentiate from other types of acute diarrhoea Group O blood group highest risk
6. How is it treated? Greatest risk in first 24 hours, so re-hydrate as soon as possible Normally ORS (rice- rather than glucose-based reduces purge rate,- sodium = or > 75mmol/l) If vomiting, give intravenous fluid replacement (eg Ringers lactate) –extreme cases. Give food as soon as patient can take it Extreme cases only should have 1-3 days antibiotic (esp doxycycline single dose) to shorten illness, when vomiting stops
7. How is it prevented? Blocking routes of transmission – water disinfection (source and /or household), hand washing, sanitation, good food hygiene and well-cooked Cholera vibrio doesnt like acid environment (block with acidic water eg. With citrus juice, healthy stomach acid levels, acid food) Oral vaccine (Dukoral) only for IDP setting
8. What proportion will die? Most people who die, do so within the first day of symptoms appearing Without any treatment about 50% of people survive With adequate re-hydration less than 2% will die With good surveillance, rapid establishment of re- hydration, and anti-biotics for worst cases, almost all deaths can be avoided (<0.2% die)
9.Risky cultural practices/ beliefs The following beliefs about causes of cholera may reduce effectiveness of key messages -: Witchcraft, eye, wind, climatic change cause the sickness Childrens stools are not dangerous Soap is believed to wash away luck The following practices increase risks Anal washing is often not followed by hand-washing Handshaking transfers bacteria directly from one person to the next Burial ceremonies may spread disease
10. What are Key Messages? Bad water is one source of cholera (disinfect source or stored water) but others, especially contaminated food (clean and cook well) and associated lack of hand washing (essential times and methods for handwashing) should also be highlighted Rapid transfer to clinics or use of ORT corners speeds up treatment and reduces cross infection. Re-hydration as early as possible saves the most lives- water quality in OR is of little importance Good surveillance systems can identify causes and reduce infection rates
Africas global dominance?
West Africa League Table
Endemic 1. Cholera reservoir, constant or sporadic few cases Epidemic. Triggered by factors in 4. reaches peak and then preventive measures dominate Endemic 2. Continued levels higher than endemic 1 while person to person infection continues Typical cholera curve