Author

Sean Schafer

Date

March 2012

Document Type

Thesis

Degree Name

M.P.H

Department

Dept. of Public Health and Preventive Medicine

Institution

Oregon Health & Science University

Abstract

Surveillance of transmitted antiretroviral mutations detects emerging drug resistance, informs pre- and post-exposure prophylaxis, highlights HIV transmission from source cases already in care, and guides efforts to control resistance. We established a statewide surveillance system for transmitted antiretroviral resistance in Oregon that relies on laboratory reporting of nucleic acid sequences ascertained for clinical purposes. We evaluated reporting completeness and representativeness, compared Oregon to U.S. resistance estimates, and compared cases with transmitted resistance to newly-diagnosed cases without resistance. During 2007–2011, laboratories reported 49 percent (1,067/2,175) of expected tests, 73 percent (316/435) for 2011. Among 1,226 patients newly diagnosed with HIV during 2007–2011, resistance tests collected within 3 months of diagnosis were reported for 24.5 percent (300), and 39.6 percent during 2011 alone. We observed no significant differences among newly-diagnosed patients with and without reported resistance tests. Overall, 17.3 percent of newly-diagnosed cases had at least one resistance mutation for any of three classes; this was not significantly different from a 2006 U.S. survey. We also found that 12.3 percent had at least one nucleoside reverse transcriptase inhibitor mutation (NRTI); 5.7 percent had at least one non-nucleoside reverse transcriptase inhibitor (NNRTI) mutation, and 2.7 percent had at least one protease inhibitor (PI) mutation. The proportion of cases with NRTI resistance was twice the proportion reported by the earlier study (p<0.001); NNRTI and PI mutations were less frequent than expected, though not significantly so. We observed no significant differences among newly-diagnosed cases with and without evidence of resistance. This approach appears to accurately represent the proportion of newly infected cases with transmitted resistance and to have the potential to be replicable by other statewide HIV surveillance systems without substantial new costs.

Identifier

doi:10.6083/M49S1P1N

School

School of Medicine

Share

COinS
 
 

To view the content in your browser, please download Adobe Reader or, alternately,
you may Download the file to your hard drive.

NOTE: The latest versions of Adobe Reader do not support viewing PDF files within Firefox on Mac OS and if you are using a modern (Intel) Mac, there is no official plugin for viewing PDF files within the browser window.