Multiagent-based Simulation of the HIV/AIDS Spatial and Temporal Transmission among Injection Drug Users

18th International Conference on Geoinformatics, Beijing, China, 18-20 June 2010

Jianhong Xiong, Jiasheng Wang, Kun Yang, Shuangyun Peng, and Quanli Xu

“In 1989, HIV was detected amongst injecting drug users (IDUs) in Yunnan province. Needle sharing drove the epidemic and HIV spread rapidly to IDUs in neighboring cities and along drug trafficking routes. By 2002, HIV was present amongst IDUs in all mainland Chinese provinces. It is believed that IDUs may have been the core source for all later sub-epidemics in China. Agent-based modeling (ABM) is the dominant paradigm in social complex network simulation which allows one to simulate the complex systems emerge from the bottom-up are composed of a multitude of heterogeneous objects called agents. This article puts forward an HIV/AIDS spatial and temporal transmission model of IDUs based on the multivalent system and geographic information systems (GIS) in an urban environment, and simulates the HIV/AIDS spatial and temporal transmission process among injection drug users during 10 years on the Repast Simphony1.2 platform. In the model, the crowd is classified into 5 types: healthy person, HIV person, AIDS person, IDU person and HIV-IDU person. Individuals represented by agents are associated to places where they interact with each other. The relationship among different agents is described with random social network. To better represent individuals in reality, each agent has its only sex, age, career, education, geographic location and other attributes. In each time step, the model defines these agents’ specific behavioral rules. The model is implemented using the propagation of HIV/AIDS among injection drug users in Yunnan province southwest of China as a case study. The simulation results show that the number of initial HIV in injection drug users, the proportion of needle sharing and individual social impact have influence on the spread of HIV/AIDS in Kunming. The results also reveal the increasing HIV/AIDS transmission among injection drug users and interpret the necessity of carrying out solutions to contain the transmission of HIV/AIDS.”

California GIS Community to Convene in Sacramento for CalGIS 2012

URISACalGIS 2012 – the 18th Annual California GIS Conference – will take place April 11-13, 2012 at the Sheraton Sacramento. The conference features a comprehensive educational program, networking events and an exhibit hall.

Themed “Capitalizing on Spatial Technology”, the conference opens on Wednesday, April 11 with numerous workshops, meetings, and a Levee and Wine tour. On Thursday, April 12, Scott Gregory, the State of California’s GIO, will update attendees on statewide GIS activities and priorities followed by a Town Hall session, where attendees will share their perspectives about issues impacting the profession.

Sessions on topics ranging from Web and Open Source Resources for GIS to Visual Simulations and the Use of LiDAR will provide attendees with top-quality education on Thursday and Friday. An Ignite session and a poster session will complement the multiple breakout sessions.

The California Geographic Information Association (CGIA) will honor 2012 award winners and Dr. Dawn Wright will provide a keynote address on “The Age of Science and Big Data”.

The committee is organizing a number of networking events including a geocaching tour of downtown Sacramento and an urban bike tour.

Don’t miss the best in California GIS this April in Sacramento. For details and registration, visit

Sponsored by:

  • Northern California Chapter of URISA – host chapter
  • Southern California Chapter of URISA
  • Central California Chapter of URISA
  • California Geographic Information Association (CGIA)

[Source: URISA press release]