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The Haiti Cholera Outbreak
Tom Mahin
July 16, 2013 Presentation
Current Status of the Outbreak
• As of July 6, 2013, there have been 664,921 cholera cases and 8,178 cholera deaths in Haiti.
From MSPP
Introduction to Cholera “In its most severe form, cholera is one of the swiftest lethal infectious diseases known, characterized by an explosive outpouring of fluid and electrolytes within hours of infection that, if not treated appropriately, can lead to death within hours. In places where drinking water is unprotected from fecal contamination, cholera can spread with stunning speed through entire populations. These two characteristics of cholera have yielded a reputation that evokes fear and often panic. However, with prompt and appropriate treatment, mortality can be kept low.” - UNICEF Cholera Manual
What is Cholera?
• Cholera is caused by Vibrio cholerae bacteria that act by attaching to cells that line the intestine where it produces a toxin that interferes with the normal cellular processes of absorption and secretion of fluid and electrolytes.
• Up to 50 per cent of infected people could develop severe dehydration with high mortality risk if left untreated.
Cholera Risk Factors
UNICEF Cholera Manual 2013
Pregnancy and Cholera
• Cholera patients who are pregnant have additional risk factors for more severe outcomes.
• The greatest potential impact of maternal cholera infection affects the outcome of the newborn because cholera infection in the third trimester poses a greater risk of spontaneous abortion and premature delivery.
• Poor outcomes are due to dehydration and reduced blood flow to the placenta.
From UNICEF Cholera Toolbox 2013
Survival Times for V. Cholerae Bacteria
Climate Change & Cholera
Climate change potentially increases the risk of cholera in a number of ways:
• the growth of bacteria, like V. cholerae in the
environment substantially increases at higher temperatures.
• severe natural disasters damage water and sanitation infrastructure and create higher transmission risk.
Haiti Overview
From the 2013 UN Humanitarian Action Plan (Mid-year Review)
• “Following long periods of drought and the destruction of harvests by Tropical Storm Isaac and Hurricane Sandy in 2012, more than 15% of Haitians face a significant risk of food shortages …”
• “As many as 81,600 children under five are acutely malnourished; 20,000 of these suffer severe acute malnutrition and are nine times more likely to die than healthy children.”
• “The upcoming rainy and hurricane season is likely to bring about an increase in cholera cases…while funding gaps have led to a serious decrease in the capacity to respond.”
“We had barely picked ourselves up”
• “We had barely picked ourselves up after the earthquake when the cholera fell on us.” - Jocelyne Pierre-Louis, a senior Haitian health official
• Haiti's outbreak "is one of the largest cholera epidemics in modern history to affect a single country."
- Jon Andrus, deputy director of the PAHO
Some Cholera Risk Factors in Haiti • Low safe drinking water & improved sanitation coverage
• Hygiene – food handling & inadequate hand washing
• Natural disasters and rainy season(s)
• Topography is conducive to flooding
• Lack of pre-existing immunity at onset of outbreak
• Economic situation/poverty increases risk
• Household member with cholera increases risk of cholera for whole family
• Children with malnutrition
• Remote areas have dramatically higher mortality risk
• Dramatically reduced number of cholera treatment centers/units in 2013 increases mortality risks
Low Improved Sanitation Coverage
Sanitation/Hygiene at Markets
All photos by T. Mahin
Topography in Haiti is Conducive to Flooding
High Flood Risk Areas
Haiti: Recent Floods (as of June 30, 2013)
From OCHA
Hurricanes/Tropical Storms During the Outbreak
Non-Functioning Water Systems (line reportedly inadvertently cut by road project)
Hygiene/Handwashing Issues
High Poverty/Unemployment Rates
The Epicenter of the Cholera Outbreak
From Piarrou et al. Understanding the Cholera Epidemic, Haiti July 2011 EID
Grande Saline
Desdunes
Haiti Cholera Strain Has Increased Virulence
• The current cholera pandemic caused by the “El Tor” cholera strain has been spreading worldwide since 1960. Subsequently studies revealed “altered El Tor” strains.
• Compared to the typical El Tor pandemic strain, the “altered El Tor” strain in Haiti is linked to increased production of cholera toxin and more severely dehydrating diarrheal disease.
• In a CDC study in Haiti “Median time from illness onset to death was ……12 hours (range 2 hours–8 days) for community decedents”
– Routh et al. “Rapid assessment of cholera-related deaths, Artibonite Department, Haiti, 2010” Emerg Infect Dis
Dr. Sacks of John Hopkins: "Cholera is an environmental bacterium. It can persist in the environment for many, many years without any human infection. ...”
From UCLA http://www.ph.ucla.edu/epi/snow/cholera_haiti.html
Cholera & IDP Camps in Port au Prince
• The earthquake of January 12, 2010, destroyed homes, schools, government buildings, and roads around Port-au-Prince; killing 230,000 persons and injured 300,000 and one and a half million residents sought shelter in internally displaced person (IDP) camps.
• Drinking water systems - portable tanks filled by trucked in water from deep boreholes and then chlorinated in the camps - were installed by a number of NGOs including Oxfam.
• When the outbreak arrived on Port au Prince, cholera attack rates in the IDP camps were much lower than in Artibonite and other areas (source – The CDC journal Emerging Infectious Diseases).
Preparing Chlorine Solution for Tanks & Chlorine Residual Testing - IDP Camps (after the earthquake)
Hurricane Tomas (Nov. 5, 2010)
From Tapero and Tauxe Emerging Infectious Diseases Vol. 17, No. 11, November 2011
Original Graph from MSPP/DINEPA
Impact of the Rainy Season(s) and Hurricane Sandy on the Number of Cholera Cases
Comparison of Cholera Cases by Year
From MSPP
New Cholera Cases (per month) 2013
From OCHA
Cholera Treatment Units (CTU/UTC)
Water Sources During the Cholera Outbreak
“ Sous” – Water Source - Hole in Ground Near River/Stream
Sous after Hurricane Sandy
Unprotected Dug Wells
Direct Use of Surface Water
Highly Contaminated Source after Rain Events
Highly Contaminated Source after Rain Events
Using Canal Water (Desdunes, Artibonite)
Turbidity 259 NTU
Examples of Oxfam’s Cholera-WASH Approach
• Repaired gravity flow water systems (GFSs) in Artibonite
• E. coli (m. ColiBlue 24) & turbidity testing of water sources to confirm appropriate locations for chlorine dispensers
• Installed hand drilled wells & hand pumps in Artibonite
• Distribution of large numbers of Aquatabs & soap
• Installed and monitored chlorine dispensers at community water sources in Nippes
Oxfam Cholera-WASH Activities (continued)
• Installed in-line tablet chlorination systems in Nippes
• Installed latrines at schools and homes
• Trained & worked closely with local water committees
• WASH cholera prevention messaging (e.g. radio)
• Provided WASH supplies to cholera treatment centers
• Installed rainwater collection systems at CTUs
• Installed protected dug wells with “rope pumps” in Artibonite that are easy to maintain and repair
• Oxfam installed chlorine dispensers in Nippes (1 of 10 “Departments” in Haiti) because of high CFRs there & because of the scarcity of other NGOs working on WASH
Chlorine Dispensers at Springs
Chlorine Dispensers at Hand Pumps
Partnered with International Action for In-Line Chlorination of Gravity Water Systems with “Tablets”
Delivering Chlorine (“HTH”) to a Water Committee Member
Hand Drilling Wells
Repairing Broken Water Pipes Using Compression Couplings
New Rope Pump and Protected Well
E. Coli Testing (with m. ColiBlue 24)
E. Coli/Total Coliform Bacteria - 10:1 Dilution
E. Coli Results (Water Source)
Free Chlorine Testing of Treated Water
Comparing Chlorine Testing
Equipment
Community Meeting in a Remote Mountain Village Prior to Chlorine Dispenser Installation
Distribution of Aquatabs & Soap
Street Side Water Treatment Messaging for Cholera Prevention
Oral Rehydration Therapy “ORT Corners” in Communities
Four-Cabin Latrine Construction at Schools & Homes
Repair of Gravity Flow Water Systems
Support to National Water Supply & Sanitation Agency (DINEPA)
Logistical Issues
Acknowledgements
• Bill and Melinda Gates Foundation
• Innovations for Poverty Action (IPA)
• International Action – Haiti
• ECHO
• Hach
• MSPP & DINEPA
• UNICEF