Karla Wagner, Ph.D.

Karla Wagner


I conduct mixed methods social network research using health behavior theories to examine the individual, social, and environmental factors associated with opioid overdose and HIV among people who use drugs and other groups at risk. In 1999 I started working with syringe access programs to identify ways to reduce risk for HIV among people who inject drugs. Since 2006 I have studied opioid overdose, with a focus on programs to expand access to naloxone, reduce opioid overdose deaths, and increase access to effective, evidence-based treatment. Through my research, I collaborate with clinical, social service, public health, behavioral health, and criminal justice stakeholders to identify factors that elevate the risk for negative health outcomes, evaluate innovative programs to reduce HIV transmission and overdose, and inform public health policy making.

Recent NevadaToday stories

Current research grants


A network-based, mixed methods study to identify and support multiple overdose responders and inform overdose prevention interventions
NIDA/NIH (R01DA057682)
9/30/2022 – 9/30/2025
Role: PI

Evaluating naloxone-on-release from incarceration as community overdose prevention
NIDA/NIH (R01DA055673; PI: Davidson)

7/1/2022 – 6/30/2027
Role: Co-PI

A Multi-Site Mixed Methods Study of Methamphetamine Use in the Mountain West
Centers for Disease Control and Prevention (R01CE003356)
9/30/2021 – 9/29/2024
Role: Co-PI (mPI: Wagner & Page)

Improving low-threshold naloxone-on-release from incarceration
NIH HEAL Initiative JCOIN J-RIG (PI: Davidson)
2021 - 2022
Role: Consultant

Incorporating guidelines into practice through policy: The effect of opioid prescribing policy on receipt of guideline-concordant pain care for Medicaid patients in Nevada
National Institute on Drug Abuse (R15DA049195-01; PI: Friedman)
2020 - 2022
Role: Co-I

Testing the effects of Mobile Recovery Teams to improve outcomes and link to medication-assisted treatment (MAT)
Arnold Ventures
May 1, 2019 – April 30, 2020
Role: PI

Selected publications (since 2021)


  • Wagner KD, *Marks C, *Felsher M, Latkin C, Pearson JL, Falade-Nwulia OO. Individual and social network correlates of responding to multiple overdoses among a cohort of people who use drugs. Drug and Alcohol Dependence Reports. 2022;5. https://doi.org/10.1016/j.dadr.2022.100107
  • Marks C, Wagner KD.(2022) Supporting people responding to overdoses. Invited commentary in The Lancet Public Health. 7(3) e198-e199. DOI:https://doi.org/10.1016/S2468-2667(22)00011-1
  • Harding, R.W., Wagner, K.T., Fiuty, P., Smith, K.P., Page, K., Wagner, K.D., (2022) “”It’s called overamping”: Experiences of overdose among people who use methamphetamine”. Harm Reduction Journal. 19(1): 1-11.
  • *Johnson, L.M., Green, H.D., Lu, M., Stockman, J.K., Felsher, M., Roth, A.M., Wagner, K.D. (2022) Who can I ask? Who would I tell?: An egocentric network analysis among a sample of women at risk for HIV to explore anticipated advice-seeking and disclosure around pre-exposure prophylaxis (PrEP). AIDS and Behavior. https://doi.org/10.1007/s10461-022-03621-9
  • *Rhed, B.D., Harding, R.W., *Marks, C., Wagner, K.T., Fiuty, Ph., Page, K., Wagner, K.D. (2022) Patterns of and rationale for the co-use of methamphetamine and opioids: Findings from qualitative interviews in New Mexico and Nevada. Frontiers Psychiatry, 13.
  • *Johnson LM, Devereux PG, Wagner KD. (2022) The group-based law enforcement mistrust scale: psychometric properties of an adapted scale and implications for public health and harm reduction research. Harm Reduction Journal. 2022;19(1). https://doi.org/10.1186/s12954-022-00635-3
  • Ray, B., Hedden, B.J., Carroll, J.J., del Pozo B., Wagner, K.D., Kral, A.H., O’Donnell D., Victor, G., Huynh, P. (Accepted July 11, 2022). Prevalence and correlates of incarceration following emergency medical services response to overdose. Drug and Alcohol Dependence.


  • *Johnson, L.M., Green Jr., H.D., Koch, B., Stockman, J.K., Felsher, M., Roth, A.M., & Wagner, K.D. (2021). The role of social networks and social norms in anticipated PrEP use in a racially-diverse sample of at-risk women and members of their social networks. Journal of Acquired Immune Deficiency Syndrome. 86(4): 422-429
  • *Johnson, L.M., Green Jr., H.D., Koch, B., Harding, R., Stockman, J.K., & Wagner, K.D. (2021). Correlates of medical mistrust among minority women at risk for HIV and their networks. Health Education & Behavior. https://doi.org/10.1177/1090198120986783
  • Wagner, K.D., Koch, B., *Bowles, J.M., §Verdugo, S.R., Harding, R.W., Davidson, P.J. (2021). Ethnographic decision tree modeling to identify factors associated with calling 911 for an overdose. American Journal of Public Health. e1-e3 https://ajph.aphapublications.org/doi/full/10.2105/AJPH.2021.306261
  • *Bowles JM, Smith LR, Mittal ML, Harding, R.W., Copulsky, E., Hennessy, G., §Dunkle, A., Davidson, P.J., Wagner, K.D. (2021) “I wanted to close the chapter completely … and I feel like that [carrying naloxone] would keep it open a little bit”: Refusal to carry naloxone among newly-abstinent opioid users and 12-step identity. International Journal of Drug Policy. 2021;94:103200. https://doi.org/10.1016/j.drugpo.2021.103200
  • *Pullen, E., Gukpta, A., Stockman, J.K., Green, H.D., Wagner, K.D.. (2021). Association of Social Network Characteristics with HIV Knowledge, Stigma, and Testing: Findings from a Study of Racial and Ethnic Minority Women in a Small Western City. AIDS CARE. https://doi.org/10.1080/09540121.2021.1913717.
  • *Ajumobi, O. Verdugo, S.R., Labus, B., *Reuther, P., Lee, B., Koch, B., Davidson, P.J., Wagner, K.D. (accepted 11 Sept 2021). Identification of Non-Fatal Opioid Overdose Cases Using 9-1-1 Computer Assisted Dispatch and Prehospital Patient Clinical Record Variables. Prehospital Emergency Care.  https://doi.org/10.1080/10903127.2021.1981505
  • Smith, K.P., Oman, R.F., Lu, M., Dawkins, A.D., Harding, R.W., Hepworth, K., Wagner, K.D. (accepted 6 Oct 2021). The Mobile Emergency Recovery Intervention Trial (MERIT): Protocol for a 3-Year Mixed Methods Observational Study of Mobile Recovery Outreach Teams in Nevada’s Emergency Departments. Plos ONE. 16(10): e0258795. https://doi.org/10.1371/journal.pone.0258795

*denotes student/trainee author


  • PhD, Preventive Medicine (Health Behavior Research), University of Southern California
  • MA, Anthropology, Northern Arizona University
  • BA, Anthropology, University of Colorado, Boulder