OBJECTIVE: A recent HIV outbreak in a rural network of persons who inject drugs (PWID) underscored the intersection of the expanding epidemics of opioid abuse, unsterile injection drug use (IDU), and associated increases in hepatitis C virus (HCV) infections. We sought to identify US communities potentially vulnerable to rapid spread of HIV, if introduced, and new or continuing high rates of HCV infections among PWID. DESIGN: We conducted a multistep analysis to identify indicator variables highly associated with IDU. We then used these indicator values to calculate vulnerability scores for each county to identify which were most vulnerable. METHODS: We used confirmed cases of acute HCV infection reported to the National Notifiable Disease Surveillance System, 2012-2013, as a proxy outcome for IDU, and 15 county-level indicators available nationally in Poisson regression models to identify indicators associated with higher county acute HCV infection rates. Using these indicators, we calculated composite index scores to rank each county's vulnerability. RESULTS: A parsimonious set of 6 indicators were associated with acute HCV infection rates (proxy for IDU): drug-overdose deaths, prescription opioid sales, per capita income, white, non-Hispanic race/ethnicity, unemployment, and buprenorphine prescribing potential by waiver. Based on these indicators, we identified 220 counties in 26 states within the 95th percentile of most vulnerable. CONCLUSIONS: Our analysis highlights US counties potentially vulnerable to HIV and HCV infections among PWID in the context of the national opioid epidemic. State and local health departments will need to further explore vulnerability and target interventions to prevent transmission.

We appreciate the points that Dr. Westfall makes in his Letter to the Editor and agree that a deeper understanding of the local context is needed for appropriate HIV and hepatitis C virus (HCV) prevention planning. Dr. Westfall identified 2 examples when local context could inform assessment of local vulnerability to rapid spread of HIV or HCV infection: how prison or jail populations may affect infection rates in a community and how travel patterns affect the likelihood someone may be exposed to HIV or HCV infection. | Our analysis was intended to provide a national overview of potential vulnerability to rapid spread of HIV or HCV infection among persons who inject drugs and could not account for all the local contextual factors that may influence vulnerability. For example, our analysis only partially accounts for the location of some institutions, such as prisons or jails, in the United States. However, the first step of the analysis identified factors significantly associated with county-level acute HCV rates as a proxy for unsafe injection drug use. Notification to Centers for Disease Control and Prevention (CDC) of cases of acute HCV infection is based on where the person is staying at the time of disease onset or diagnosis1; thus, the indicators we identified accounted for the characteristics of persons likely engaging in unsterile injection drug use and in need for HIV and HCV prevention or treatment services, irrespective of institutionalization. A county, such as Crowley County, may have a higher rate of acute HCV infection among incarcerated persons than the general population, and a local understanding of that difference could help direct prevention services appropriately. Second, we applied a national estimate of the average daily distance traveled to calculate the average rate of people living with HIV in and around the counties we identified as most vulnerable. States may consider alternatives for calculating this HIV proximity estimate, such as adjusting for local travel patterns or using a different measure such as population density. We agree that state and local health departments should use locally available data to better understand local vulnerability to rapid spread of HIV or HCV infection among persons who inject drugs. We also recommend that local health departments assess the availability of local services, such as Syringe Services Programs. As seen in Figure 1, Syringe Services Programs were typically not available in the vulnerable counties. Information on local data and services is necessary to guide the public health response.

OBJECTIVE: In 2011, the National Health Interview Survey (NHIS), an in-person household interview, revised the human immunodeficiency virus (HIV) section of the survey and the Behavioral Risk Factor Surveillance System (BRFSS), a telephone-based survey, added cellphone numbers to its sampling frame. We sought to determine how these changes might affect assessment of HIV testing trends. METHODS: We used linear regression with pairwise contrasts with 2003-2013 data from NHIS and BRFSS to compare percentages of persons aged 18-64 years who reported HIV testing in landline versus cellphone-only households before and after 2011, when NHIS revised its in-person questionnaire and BRFSS added cellphone numbers to its telephone-based sample. RESULTS: In NHIS, the percentage of persons in cellphone-only households increased 13-fold from 2003 to 2013. The percentage ever tested for HIV was 6%-10% higher among persons in cellphone-only than landline households. The percentage ever tested for HIV increased significantly from 40.2% in 2003 to 45.0% in 2010, but was significantly lower in 2011 (40.6%) and 2012 (39.7%). In BRFSS, the percentage ever tested decreased significantly from 45.9% in 2003 to 40.2% in 2010, but increased to 42.9% in 2011 and 43.5% in 2013. CONCLUSIONS: HIV testing estimates were lower after NHIS questionnaire changes but higher after BRFSS methodology changes. Data before and after 2011 are not comparable, complicating assessment of trends.

In the United States, an estimated 1.2 million persons are living with human immunodeficiency virus (HIV), a serious infection that, if untreated, leads to illness and premature death. Persons living with HIV who use antiretroviral therapy (ART) and achieve very low levels of the virus (suppressed viral load) can have a nearly normal life expectancy and have very low risk for transmitting HIV to others. However, each year in the United States, nearly 50,000 persons become infected with HIV. Each step along the HIV care continuum (HIV diagnosis, prompt and sustained HIV medical care, and ART) is essential for achieving a suppressed viral load.

Approximately 16% of the estimated 1.1 million persons living with human immunodeficiency virus (HIV) in the United States are unaware of their infection and thus unable to benefit from effective treatment that improves health and reduces transmission risk. Since 2006, CDC has recommended that health-care providers screen for HIV all patients aged 13-64 years unless prevalence of undiagnosed HIV infection in their patients has been documented to be <0.1%. This report describes novel HIV screening programs at the Urban Health Plan (UHP), Inc. in New York City and the Interim Louisiana Hospital (ILH) in New Orleans. Data were provided by the two programs. UHP screened a monthly average of 986 patients for HIV during January 2011-September 2013. Of the 32,534 patients screened, 148 (0.45%) tested HIV-positive, of whom 147 (99%) received their test result and 43 (29%) were newly diagnosed. None of the 148 patients with HIV infection were previously receiving medical care, and 120 (81%) were linked to HIV medical care. The ILH emergency department (ED) and the urgent-care center (UCC) screened a monthly average of 1,323 patients from mid-March to December 2013. Of the 12,568 patients screened, 102 (0.81%) tested HIV-positive, of whom 100 (98%) received their test result, 77 (75%) were newly diagnosed, and five (5%) had acute HIV infection. Linkage to HIV medical care was successful for 67 (74%) of 91 patients not already in care. Routine HIV screening identified patients with new and previously diagnosed HIV infection and facilitated their linkage to medical care. The two HIV screening programs highlighted in this report can serve as models that could be adapted by other health-care settings.