Sunday, 8 April 2012

West Bengal Flood of 1998

by Nadiya & Ilija

What was the natural disaster?

The natural disaster was a flood in west Bengal.
West Bengal

Where was it located?

West Bengal

According to the National Institute of Cholera & Enteric Diseases (ICMR), Calcutta (2000) in 1998, West Bengal suffered one of its worse ever floods. Despite flooding being common in this country, the floods of 1998 were particularly severe resulting in many deaths. During the period between August and October 1998, 16,590 cases were reported with 276 deaths (case fatality rate of 1.7%) (D, S., & P, D.,2000). Twenty one of 29 (72%) rectal swabs were positive for Vibrio cholera O1 (D, S., & P, D.,2000).

Who lived there?

Bengalis. LEDC’s population, which means a population of less economically developed country. 

Population Map of India

Was it an already vulnerable population?

Yes it was. West Bengal is an LEDC and its lack of money and heavy national debt means that little money is available to spend on flood protection methods and many existing defenses lack upkeep and are of questionable use.

Why did it occur (i.e. the science behind the disaster?)

Physical landscape, conditions of the country and the impact of its population all affect the result of having a natural disaster.

West Bengal is just on the border of Bangladesh and is affected in the same way

Explain how this natural disaster promoted or let to the spread of this disease (i.e. infrastructure damage, movement of the population, introduction of aid workers)

Floods can potentially increase the transmission of the following communicable diseases: Water-borne diseases, such cholera (World Health Organization, 2012, p.1).
National Institute of Cholera & Enteric Diseases point out that an explosive epidemic of cholera in the district of Malda in the state of West Bengal, was induced by devastating floods resulting from overflowing of the two main rivers of the district, at the end of July 1998, affecting 15 blocks and 2 municipalities (D, S., & P, D. (2000). An investigation was conducted to understand the epidemiological characteristics, identify the factors and clinical management and suggest control measures (D, S., & P, D. (2000)

"A lot of land was covered by water. Contamination of water by waste and dead bodies / animals, and the lack of a clean water supply resulted in the spread of disease such as cholera. Communications became difficult, with shopping impossible in the main port, as well as roads and railways having been swept away making the distribution of aid and the rescue operation very difficult" (Flooding in an LEDC, 2006).

How did this disease spread? (i.e. the type of organism, mechanism of spread, probability of spread-some math!-based on population measures)

Vibrio Cholera is the pathogenic(decease-causing)  bacteria that causes cholera.  V. Cholera typically is a marine species of bacteria but also has the ability to survive well in fresh water. Cholera gets into human population when people eat contaminated raw shellfish or when the bacterium makes its way into drinking water supplies. From that point, the highly contagious cholera is passed on from one person to the next. (Mark Hecht et al., 2012, p.141) Due to the high population of West Bengal people were forced to be crowded with each other and water supply was contaminated. Therefore, when a few people got the disease it spread very fast amongst the population (Mark Hecht et al., 2012, p.141)

What are symptoms of the disease?

According to the World Health Organization (2012) Cholera is an acute infection of the intestine, which begins suddenly with painless watery diarrhea, nausea and vomiting. Most people who become infected have very mild diarrhea or symptom-free infection. Malnourished people in particular experience more severe symptoms. Severe cholera cases present with profuse diarrhea and vomiting. Severe, untreated cholera can lead to rapid dehydration and death. 50% of people with severe cholera will die if untreated. However prompt and adequate treatment reduces this to less than 1% of cases(World Health Organization, 2012).

What is the treatment to control the disease? Note, the treatment might be different for a disease epidemic compared to an individual outbreak.  Was there technology used?

To prevent the spread of cholera, the following four interventions are essential (World Health Organization, 2012):

  • Provision of adequate safe drinking-water
  • Proper personal hygiene
  • Proper food hygiene
  • Hygienic disposal of human excreta.
Treatment of cholera consists mainly in replacement of lost fluids and salts. The use of oral re-hydration salts (ORS) is the quickest and most efficient way of doing this. (World Health Organization, 2012, para. 5)

What is the current status of this disease in the community? What has contributed to the success or failure to eradicate or minimize the disease outbreak? 

There have been several cases of cholera related outbreaks since 1998 in West Bengal. For example, on 10th March 2010, an outbreak of diarrheal disease was reported among workers of a jute mill in Kolkata, West Bengal reported by Daniela Salas (2011). 
Also there are few statistics on Cholera in West Bengal: like epidemiological findings for pond-centered cholera outbreaks in 2004-2008 show many reasons why cholera is so common in West Bengal.

There is still a lot of improvement popultaion and health services of West Bengal have to do in order to reduce cholera outbreaks in the community. 

Would the effect of this natural disaster be the same or different if they occurred in a different part of the world? For, example, you might want to consider climate, population density, technological advances, economic situation, cultural differences, etc.

The effect of this natural disaster would be different if they occurred in a different part of the world mostly because West Bengal is considered LED (Less Developed Country) which makes is harder to prevent the disease because of not enough finances, low technology development etc.  High population also makes the difference because high population in a small territory with a bad economic development and low finances would be forced to live in bad conditions; number of people living in the same tents, people crowded with each other- easier for the disease such as cholera to spread.