Modeling the transmission of HIV in the Texas State Prison population

Due to the character of the original source materials and the nature of batch digitization, quality control issues may be present in this document. Please report any quality issues you encounter to digital@library.tamu.edu, referencing the URI of the item.Includes bibliographical references (leaves 30-31).Issued also on microfiche from Lange Micrographics.An infectious disease that is widespread globally is acquired immune deficiency syndrome (AIDS). AIDS is spread by the human immunodeficiency virus (HIV). The purpose of this study was to develop a simulation model to study the transmission of HIV via intravenous drug use in a Texas State prison population. By developing a model to track the movement of HIV in the prison, public health authorities could suggest policies to better serve those HIV positive prisoners released into the general population. Also, this model provided a means to quantitatively study the effect of intervention strategies against the virus (increase or reduction of infection rate). The minimum-security prison of Huntsville, Texas, was chosen as the site for the simulation study. Parameter values were estimated from data in existing literature. Vital statistics such as the mean number of prisoners without HIV, with HIV, and those with AIDS were collected and analyzed at the end of 10 years. Simulation schemes were structured on an event driven basis, the existence of syringes in prison by smuggling, or no syringes in prison. A parametric analysis was conducted by changing three of the parameters one at a time: the probability of syringe smuggling, the probability of a newly admitted prisoner to be HIV positive, and the mean number of injections per day Results from the base run showed that there were more than 3 infections per syringe-existing day, or about 0.2% of the prison population. Successful syringe smuggling translated into HIV transmission of anywhere from 3 to more than 20 new infectives per virus spreading event period. These numbers are alarming, as this would reach epidemic proportions. Results from the parametric analysis showed that most of the HIV positives released were a result of syringe sharing and most of the prisoners who developed AIDS were from prisoners admitted into prison with HIV. The structure and procedure of this simulation model can be employed to study other epidemics that may threaten public health. By using our simulation model as a basis, models could be developed to study other infectious diseases and in different types of environments