Archive

Posts Tagged ‘cholera’

Informal urban settlements and cholera risk in Dar es Salaam

April 19, 2010 Leave a comment

PLoS Negl Trop Dis. 2010 Mar 16;4(3):e631.

Informal urban settlements and cholera risk in Dar es Salaam, Tanzania.

Full-text:  http://www.plosntds.org/article/info%3Adoi%2F10.1371%2Fjournal.pntd.0000631

Penrose K, et al.

BACKGROUND: As a result of poor economic opportunities and an increasing shortage of affordable housing, much of the spatial growth in many of the world’s fastest-growing cities is a result of the expansion of informal settlements where residents live without security of tenure and with limited access to basic infrastructure. Although inadequate water and sanitation facilities, crowding and other poor living conditions can have a significant impact on the spread of infectious diseases, analyses relating these diseases to ongoing global urbanization, especially at the neighborhood and household level in informal settlements, have been infrequent. To begin to address this deficiency, we analyzed urban environmental data and the burden of cholera in Dar es Salaam, Tanzania.

METHODOLOGY/PRINCIPAL FINDINGS: Cholera incidence was examined in relation to the percentage of a ward’s residents who were informal, the percentage of a ward’s informal residents without an improved water source, the percentage of a ward’s informal residents without improved sanitation, distance to the nearest cholera treatment facility, population density, median asset index score in informal areas, and presence or absence of major roads. We found that cholera incidence was most closely associated with informal housing, population density, and the income level of informal residents. Using data available in this study, our model would suggest nearly a one percent increase in cholera incidence for every percentage point increase in informal residents, approximately a two percent increase in cholera incidence for every increase in population density of 1000 people per km(2) in Dar es Salaam in 2006, and close to a fifty percent decrease in cholera incidence in wards where informal residents had minimally improved income levels, as measured by ownership of a radio or CD player on average, in comparison to wards where informal residents did not own any items about which they were asked. In this study, the range of access to improved sanitation and improved water sources was quite narrow at the ward level, limiting our ability to discern relationships between these variables and cholera incidence. Analysis at the individual household level for these variables would be of interest.

CONCLUSIONS/SIGNIFICANCE: Our results suggest that ongoing global urbanization coupled with urban poverty will be associated with increased risks for certain infectious diseases, such as cholera, underscoring the need for improved infrastructure and planning as the world’s urban population continues to expand.

Categories: Tanzania Tags:

Tanzania – Informal Urban Settlements and Cholera Risk

March 22, 2010 Leave a comment

PLoS Negl Trop Dis. 2010 Mar 16;4(3):e631.

Informal Urban Settlements and Cholera Risk in Dar es Salaam, Tanzania.

Penrose K, de Castro MC, Werema J, Ryan ET.

Department of Global Health and Population, Harvard School of Public Health, Boston, Massachusetts, United States of America.

BACKGROUND: As a result of poor economic opportunities and an increasing shortage of affordable housing, much of the spatial growth in many of the world’s fastest-growing cities is a result of the expansion of informal settlements where residents live without security of tenure and with limited access to basic infrastructure. Although inadequate water and sanitation facilities, crowding and other poor living conditions can have a significant impact on the spread of infectious diseases, analyses relating these diseases to ongoing global urbanization, especially at the neighborhood and household level in informal settlements, have been infrequent. To begin to address this deficiency, we analyzed urban environmental data and the burden of cholera in Dar es Salaam, Tanzania.

METHODOLOGY/PRINCIPAL FINDINGS: Cholera incidence was examined in relation to the percentage of a ward’s residents who were informal, the percentage of a ward’s informal residents without an improved water source, the percentage of a ward’s informal residents without improved sanitation, distance to the nearest cholera treatment facility, population density, median asset index score in informal areas, and presence or absence of major roads. We found that cholera incidence was most closely associated with informal housing, population density, and the income level of informal residents. Using data available in this study, our model would suggest nearly a one percent increase in cholera incidence for every percentage point increase in informal residents, approximately a two percent increase in cholera incidence for every increase in population density of 1000 people per km(2) in Dar es Salaam in 2006, and close to a fifty percent decrease in cholera incidence in wards where informal residents had minimally improved income levels, as measured by ownership of a radio or CD player on average, in comparison to wards where informal residents did not own any items about which they were asked. In this study, the range of access to improved sanitation and improved water sources was quite narrow at the ward level, limiting our ability to discern relationships between these variables and cholera incidence. Analysis at the individual household level for these variables would be of interest.

CONCLUSIONS/SIGNIFICANCE: Our results suggest that ongoing global urbanization coupled with urban poverty will be associated with increased risks for certain infectious diseases, such as cholera, underscoring the need for improved infrastructure and planning as the world’s urban population continues to expand.

Categories: Tanzania Tags:

Kenya – Refuse dumps and cholera infection in Kumasi

December 16, 2008 Leave a comment

Spatial dependency of V. cholera prevalence on open space refuse dumps in Kumasi, Ghana: a spatial statistical modelling. Author: Frank B Osei and Alfred A Duker. International Journal of Health Geographics 2008, 7:62.

Cholera has persisted in Ghana since its introduction in the early 70’s. From 1999 to 2005, the Ghana Ministry of Health officially reported a total of 26,924 cases and 620 deaths to the WHO.

Etiological studies suggest that the natural habitat of V. cholera is the aquatic environment.

Its ability to survive within and outside the aquatic environment makes cholera a complex health problem to manage. Once the disease is introduced in a population, several environmental factors may lead to prolonged transmission and secondary cases.

An important environmental factor that predisposes individuals to cholera infection is sanitation. In this study, we exploit the importance of two main spatial measures of sanitation in cholera transmission in an urban city, Kumasi.

These are proximity and density of refuse dumps within a community.

Results: A spatial statistical modelling carried out to determine the spatial dependency of cholera prevalence on refuse dumps show that, there is a direct spatial relationship between cholera prevalence and density of refuse dumps, and an inverse spatial relationship between cholera prevalence and distance to refuse dumps. A spatial scan statistics also identified four significant spatial clusters of cholera; a primary cluster with greater than expected cholera prevalence, and three secondary clusters with lower than expected cholera prevalence.

A GIS based buffer analysis and a quantitative assessment of distance discrimination of the buffer zones around refuse dumps show that the optimum spatial discrimination of cholera occurs at 500m from refuse dumps. This indicates that the minimum distance within which refuse dumps should not be sited within community centres is 500m.

Conclusion: The results suggest that proximity and density of open space refuse dumps play a contributory role in cholera infection in Kumasi.

Source – 7th Space Interactive

Categories: Kenya Tags: , , ,

Zimbabwe – Sanitation and water crises spark disease fears in urban areas

September 23, 2008 Leave a comment

Fears of serious water borne diseases spreading across Zimbabwe’s urban areas have been sparked due to severe crises within the country’s water and sanitation services – that have already led to a cholera outbreak in Harare.

At least 12 people in the capital’s Chitungwiza township have died as a result of the disease but medical officials say this number is likely much higher and merely ‘the tip of the iceberg’. Health centres in Harare as well as in Bulawayo are reportedly burdened by numerous cases of diarrhea on a daily basis and more deaths as a result are expected.

The water and sanitation situation across the country has been rapidly deteriorating as the ongoing political crisis has seen the destruction of the economy and the equal destruction of the country’s infrastructure. The Zimbabwe National Water Authority has come under heavy criticism for failing to provide a proper service – a failure that has left most homes dry and dependent on unsafe, unhealthy water supplies.

Read More

Follow

Get every new post delivered to your Inbox.

Join 82 other followers