Cholera in Haiti: Determinants (Blog 11)

Problem Definition: There have been 469.967 reported cases of cholera in Haiti between January 2010 and October 2011, resulting in 6,595 deaths.

This blog discusses the key determinants of the cholera epidemic in Haiti. All of the determinants that I’m discussing are inter-related and are difficult to separate. The determinants I will be looking at are biological, environmental and social/economic. A person’s social/economic status affects their environmental surroundings.

According to the WHO “cholera is an acute enteric infection caused by the ingestion of bacterium Vibrio cholera present in faecally contaminated water or food”. Environmental conditions allow the spread of cholera through biological determinants (faecally contaminated water or food).

Living Conditions: An estimated 634,000 people in Haiti lived in slums or displacement camps during 2010/2011. Needless to say, the slums and displacement camps were not great living conditions with cramped living spaces and had poor sanitation.  People in these camps were poor, lacked food and water. Their social/economic status affected their environmental surroundings.

           

Lowered Immunity: Overcrowded living conditions allow diseases to spread quickly and easily. All of the illnesses that the people’s immune systems were battling lead to generally lowered immune system effectiveness. Unfortunately people with lower immunity are not only more likely to be infected with cholera but they are also more likely to die from it.

Food Hygiene: UN officials estimated that 2 million people needed food supplies on a regular basis. Though food hygiene is very important, given the shortage of food, the main priority was getting food to the population. People are also more willing to eat food that may not be ‘safe’ if they are hungry. The combination of these two can result in food falling on the ground and still being consumed, not cooking food properly, etc. Food could have easily been contaminated with faecal matter further allowing the spread of cholera.

Water Sanitation: Some people – particularly those of low economic status –relied on rivers for water supply, as they were without plumbing. Not only did they do their laundry in rivers, they bathed, brushed their teeth and drank from the river. They were at risk to any contaminants dumped in the river upstream. Due to the destruction of infrastructure during the earthquake, sanitation became even poorer. Even the United Nations peacekeeping base in Meille had “significant potential for cross-contamination’ between toilets and showers”. Furthermore the UN base contaminated the Latem River. Yet the UN’s sanitation system would have been at a higher structural caliber than the general populations’. As you can imagine, if the UN base is contaminating the water than contamination from others would have been much worse. The poor water sanitation allowed the cholera to spread.

Sources:

WHO, (2012). Prevention and control of cholera outbreaks: WHO policy and recommendations. Retrieved from website: http://www.who.int/cholera/technical/prevention/control/en/index.html

2 weeks after haiti quake, food aid falls short. (2010, January 27). The Associated Press. Retrieved from http://www.msnbc.msn.com/id/35109377/ns/world_news-haiti/t/weeks-after-haiti-quake-food-aid-falls-short/

Haiti news. (2012, April 02). The New York Times. Retrieved from http://topics.nytimes.com/top/news/international/countriesandterritories/haiti/index.html

Cholera in Haiti: Surveillance, Magnitude & Indicators (Blog 10)

Problem Definition: There have been 469,967 reported cases of cholera in Haiti between January 2010 and October 2011, resulting in 6,595 deaths.

This blog will discuss the surveillance, magnitude, direct and indirect indicators of the cholera epidemic in Haiti as well as the reliability of the information.

The surveillance of the cholera outbreak is both passive and active. The passive surveillance occurs when patients seek medical attention and are diagnosed with cholera, which in turn is then reported. The active surveillance occurs in the form of cohort studies, although not always intentional. For example, agencies often check the quality of the sanitation and water supply after a natural disaster. People may get sick from the poor sanitation observed, which is then reported.

Within the first 12 months after the Haitian earthquake (January 2010- January 2011) there were an estimated 400,000 cases of which 80,000 were severe and 140,000 required hospitalization.  As of October 9 2011 there were 469,967 reported cases of cholera and 6,595 deaths. The mortality rate from cholera is 1.6%. To put all of these numbers into perspective, in 2010 the Haitian population was estimated to be 10,620,000; almost 5% of the Haitian population were sick from cholera.

Cholera is spread by the ingestion of faecal matter contaminated with Vibrio cholera. Many rivers, reservoirs and wells were likely contaminated with this bacteria which was a direct cause of the spread of cholera in 2010-2011. Improperly handled and unclean food was also a direct cause of the cholera outbreak. Again, even the slightest amount of faecal contamination spreads the disease.

The most notable indirect cause of the cholera outbreak is the earthquake that occurred in January 2010. The quake destroyed more than 250,000 homes and 30,000 businesses. It is difficult to find numbers pertaining to the damage to the general infrastructure but we can assume that it was equally as severe. The damage to these buildings and sewage systems indirectly affected the spread of cholera via the adverse impact to the overall sanitation.

On October 8, 2010 Nepalese troops deployed in Haiti to assist with the earthquake relief effort. However, Nepal had just previously experienced a cholera outbreak. It is unknown how many of these troops were infected with cholera but they would have furthered – and some have argued start – the spread of cholera within Haiti.

As discussed in my previous blog, statics from nations which have had a natural disaster and are poor countries can be rather misleading. Aside from simple data collection problems which exist even in developed countries not facing a natural disaster,  if the Haitian government wanted more money there would be an incentive to inflate the magnitude of the problem to gain public sympathy. However, as there were many agencies working in Haiti, many producing their own statistics, this influence was mitigated; there is a reliable sense of the magnitude of this cholera epidemic.

Sources:

(2011). Cholera persists in Haiti. America, 205(14), 08.

Key Haiti statistics. In (2012). The Lambi Fund of Haiti Retrieved from http://www.lambifund.org/news_HaitiStats.shtml

Renois, C. (2010, February 05). Haitians angry over slow aid. The Age. Retrieved from http://www.theage.com.au/world/haitians-angry-over-slow-aid-20100204-ng2g.html