Topography as a contextual variable in infectious disease transmission.
OBJECTIVE
This paper examines whether or not topography is a contextual variable that indirectly influences the transmission of infectious diseases. Age, gender, race/ethnicity, education level, economic status, injection drug use, and high-risk sexual behavior are known to influence infectious diseases transmission, but the effects of topography are often overlooked.


METHODS
A sample of 395 drug users were chosen from census tracts based upon a target profile of drug use behavior and demographics for the city of Houston. HIV was chosen as the infectious disease used to test this hypothesis.


METHODS
Residents of 16 census tracts in Houston, Texas participated in this study.


RESULTS
The findings revealed that census tracts that were 'isolated' by topographic barriers, such as bayous, parks, railroad tracks, railway yards, major thoroughfares, freeways, and unique street grids had fewer cases of HIV than census tracks that were more accessible to thru-traffic.


CONCLUSIONS
The research findings suggest that future research studies should consider topography as being contextually related to infectious disease transmission.
Montoya
Isaac D
ID
Affiliated Systems Corporation, Houston, TX 77027-6022, USA. imontoya@affiliatedsystems.com
D000293:Adolescent; D000328:Adult; D003141:Communicable Diseases / Q000453:epidemiology* / Q000635:transmission*; D016021:Epidemiologic Studies; D015658:HIV Infections / Q000635:transmission; D006801:Humans; D012307:Risk Factors; D019966:Substance-Related Disorders; D019371:Topography, Medical