Cholera Prevention

					     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 Ringer’s 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 doesn’t 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
• Children’s 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
Africa’s global dominance?

           Africa's percentage of Global cholera

    120%

    100%

    80%

    60%

    40%

    20%

     0%
       1996     1998     2000     2002    2004     2006
                       Country           Total cases Incidence/1000 Mortality   Incidence/1
              (sorted on mortality)      1997-2004 Ranking          Average
West Africa   Central African Republic
              Congo
                                                 785
                                               8,319
                                                                18
                                                                 5
                                                                      15.189
                                                                      11.285
                                                                                0.206579
                                                                                2.291736
              Cameroon                        16,556             9      9.639   1.051175

 League       Guinea
              Mali
                                               3,974
                                               6,276
                                                                14
                                                                12
                                                                        9.269
                                                                        8.530
                                                                                0.475359
                                                                                0.497188
              Mauritania                         576            19      8.348   0.200697
Table         Togo
              DR Congo
                                               8,536
                                             137,349
                                                                 6
                                                                 4
                                                                        6.985
                                                                        6.743
                                                                                1.778333
                                                                                2.682598
              Chad                            23,943             3      6.467   2.867425
              Niger                            4,457            16      5.968   0.386088
              Côte d'Ivoire                   11,239            10      5.495   0.686771
              Nigeria                         46,803            15      5.409   0.387086
              Burkina Faso                     2,224            20      4.071   0.180813
              Sierra Leone                     3,472            11      3.829   0.590175
              Ghana                           26,280             7      2.431   1.283767
              Benin                            7,614             8      2.290   1.189688
              Senegal                          1,598            21      1.890    0.15104
              Guinea-Bissau                   21,968             1      1.866   16.15294
              Equatorial Guinea                   59            22      1.695   0.122661
              Cape Verde                         133            17      0.752     0.3325
              Liberia                         42,497             2      0.474   12.81188
              Gabon                              635            13      0.000   0.488462

              TOTAL                         375,293
Typical cholera curve

               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