Applications of geospatial Analysis to Surveiallnce Data: A Spatial Look at HIV/AIDS Prevelence in Zambia

HIV/AIDS;Geographic Information System (GIS);Spatial Analysis;Zambia

Moise, Imelda Kanchule ; Kalipeni ; Ezekiel

关键词: HIV/AIDS;    Geographic Information System (GIS);    Spatial Analysis;    Zambia;   

Others  :  https://www.ideals.illinois.edu/bitstream/handle/2142/35272/MoiseImeldaKanchule2007.pdf?sequence=3&isAllowed=y

美国|英语

来源: The Illinois Digital Environment for Access to Learning and Scholarship

【 摘 要 】

Human immunodeficiency virus (HIV) and acquired immunodeficiency syndrome (AIDS) (HIV I AIDS) is a major public health problem in Zambia. Despite some evidencethat the pandemic may have reached a plateau or perhaps has begun to decline at the national level, HIV continues to increase in different sub-populations such as adults above 19 years old. The characterization of the spatial patterns of HIV prevalence in the country as well as description of possible determinants of HIV rate variation can direct surveillanceefforts and assist in the development of HIV I AIDS control and prevention programs.The spatial distribution of HIV prevalence per district (N=72) in Zambia for periods 1994, 1998, 2002 and 2004 were defined. Using a geographical informationsystem (GIS), a georeferenced database was created. Included in the database were sentineldata, number of pregnant women sampled, age, socio-economic and demographic data, political boundary shapefiles, road network and HIV rates per year. Spatial analysis such as inverse distance weighted (IDW), spatial statistics (Moran's I) and UNAIDS' estimationand projection package techniques were performed.Smoothed maps obtained from both IDW and zonal statistics for the four years under study reveal a spatial variation in HIV prevalence with urban and provincial districtshaving higher prevalence than rural areas. However, there was an overall trend of decreasein HIV prevalence across the country with the year 2004 exhibiting the most reduction,coinciding with protective sexual behavior campaigns operating in the country. Analysis of regression residuals indicated high spatial autocorrelation: Moran's I value was 0.28 (z = 4.12 and p < 0.000) and a highly significant Robust LM (lag), (p < 0.00000), suggestive ofa diffusion process.Furthermore, the clustering of HIV prevalence rates among interdependent districts suggest that HIV control programs in the country would require an integrated approach combining HIV prevention messages as well as an understanding of social and culturalinteractions between interdependent districts that produce behavioral diffusion of HIVprevalence rates.Future and current projections of HIV prevalence were obtained with UN AIDS'estimation and projection package techniques for periods 1980 to 2010. Results revealed asharp increase of HIV prevalence rates since 1984 when HIV was first reported in thecountry and a gradual decrease in prevalence rates thereafter. These results indicate thatHIV prevalence in Zambia is expected to stabilize or even decrease further if current trendscontinue.