Urban lymphatic filariasis in the metropolis of Dar es Salaam, Tanzania

Particle and Fibre Toxicology

Paul E Simonsen³  Franklin W Mosha¹  Erling M Pedersen³  Mwelecele N Malecela²  Mbutolwe E Mwakitalu² 

[1] KCM-College, Tumaini University, P.O. Box 2240, Moshi, Tanzania;National Institute for Medical Research, P.O. Box 9653, Dar es Salaam, Tanzania;Department of Veterinary Disease Biology, Faculty of Health and Medical Sciences, University of Copenhagen, Thorvaldsensvej 57, 1871 Frederiksberg C, Denmark

关键词: Tanzania;    Dar es Salaam;    Vectors;    Clinical manifestations;    Microfilariae;    Bm14 antibodies;    Circulating filarial antigens;    Urban;    Lymphatic filariasis;   

Others  :  824379
DOI  :  10.1186/1756-3305-6-286

 received in 2013-06-17, accepted in 2013-09-19,  发布年份 2013

【 摘 要 】

Background

The last decades have seen a considerable increase in urbanization in Sub-Saharan Africa, and it is estimated that over 50% of the population will live in urban areas by 2040. Rapid growth of cities combined with limited economic resources often result in informal settlements and slums with favorable conditions for proliferation of vectors of lymphatic filariasis (LF). In Dar es Salaam, which has grown more than 30 times in population during the past 55 years (4.4 million inhabitants in 2012), previous surveys have indicated high prevalences of LF. This study investigated epidemiological aspects of LF in Dar es Salaam, as a background for planning and implementation of control.

Methods

Six sites with varying distance from the city center (3–30 km) and covering different population densities, socioeconomic characteristics, and water, sewerage and sanitary facilities were selected for the study. Pupils from one public primary school at each site were screened for circulating filarial antigen (CFA; marker of adult worm infection) and antibodies to Bm14 (marker of exposure to transmission). Community members were examined for CFA, microfilariae and chronic manifestations. Structured questionnaires were administered to pupils and heads of community households, and vector surveys were carried out in selected households.

Results

The study indicated that a tremendous decrease in the burden of LF infection had occurred, despite haphazard urbanisation. Contributing factors may be urban malaria control targeting Anopheles vectors, short survival time of the numerous Culex quinquefasciatus vectors in the urban environment, widespread use of bed nets and other mosquito proofing measures, and mass drug administration (MDA) in 2006 and 2007. Although the level of ongoing transmission was low, the burden of chronic LF disease was still high.

Conclusions

The development has so far been promising, but continued efforts are necessary to ensure elimination of LF as a public health problem. These will include improving the awareness of people about the role of mosquitoes in transmission of LF, more thorough implementation of environmental sanitation to reduce Cx. quinquefasciatus breeding, continued MDA to high-risk areas, and set-up of programmes for management of chronic LF disease.

【 授权许可】

   
2013 Mwakitalu et al.; licensee BioMed Central Ltd.

【 图 表 】

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