Explaining clustering of sexually oriented massage parlors in Los Angeles and New York: Toward an intervention for immigrant female sex workers

Background: Sex work has increasingly moved from the streets into indoor venues, such as massage parlors, because of heightened enforcement of anti-prostitution ordinances and because of the internet. These indoor venues predominantly employ immigrant female sex workers, especially Asians. This paper examines spatial clustering of sexually oriented massage parlors in Los Angeles County and New York City as a basis for developing "upstream" interventions, which may include legal interventions, to help prevent HIV and other STIs among immigrant female massage parlor workers and their clients.

Method: Using geocoded data from an NIH-funded study of Asian immigrant sexually oriented massage parlor businesses in Los Angeles County and New York City, we conducted spatial regression analysis of massage parlor location to identify (1) spatial clustering and (2) demographic and economic factors associated with clustering. We examined the differences in clustering between LA County and NYC.

Conclusions: The results show that sexually oriented massage parlors cluster in particular Census tracts. Clustering was positively associated with Census tracts with more employees and with higher proportions of adult males, Asian residents, unemployed persons, and households below the poverty line. Clustering was negatively associated with Census tracts with higher average family size and proportion of women. Furthermore, clustering patterns for LA County and NYC were significantly different. Implications for developing spatially informed upstream health interventions will be discussed.