摘要：Objectives. We estimated the seroprevalence of both acute and chronic HIV infection by using a random sample of emergency department (ED) patients from a region of the United States with low-to-moderate HIV prevalence. Methods. This cross-sectional seroprevalence study consecutively enrolled patients aged 18 to 64 years within randomly selected sampling blocks in a Midwestern urban ED in a region of lower HIV prevalence in 2008 to 2009. Participants were compensated for providing a blood sample and health information. After de-identification, we assayed samples for HIV antibody and nucleic acid. Results. There were 926 participants who consented and enrolled. Overall, prevalence of undiagnosed HIV was 0.76% (95% confidence interval [CI] = 0.30%, 1.56%). Three participants (0.32%; 95% CI = 0.09%, 0.86%) were nucleic acid–positive but antibody-negative and 4 (0.43%; 95% CI = 0.15%, 1.02%) were antibody-positive. Conclusions. Even when the absolute prevalence is low, a considerable proportion of undetected HIV cases in an ED population are acute. Identification of acute HIV in ED settings should receive increased priority. HIV screening is recommended by the US Centers for Disease Control and Prevention as an essential component of the nation’s HIV prevention effort. 1,2 Emergency departments (EDs) are particularly emphasized as venues for HIV screening. 3–5 Emergency departments serve more than 100 million patients annually, readily accessing vulnerable populations with a high prevalence of undetected HIV. 1,4–8 To date, most attention has been focused on detection of HIV in the chronic phase, after seroconversion, by assay for antibodies. Yet identification of patients during acute HIV infection could have a significant impact on further transmission. 9,10 Testing for acute HIV infection is accomplished by assays that detect viral proteins or viral genetic material before antibody detection is possible. This testing is more expensive, complex, or may delay results compared with antibody testing. 9,11,12 Despite these disadvantages, screening for acute HIV is increasingly suggested by various authors. 9,13–19 Acute HIV infection is thought to contribute disproportionately to HIV incidence because of high viral replication and increased infectiousness during this phase. 15,20–22 Diagnosis prompts many individuals to reduce transmission behaviors, 23 and partner notification efforts may be more successful. 24 There is also renewed interest in treatment during acute HIV infection, to lower infectiousness and improve long-term patient health outcomes. 21,25–27 In light of these benefits, screening for acute HIV infection may ultimately be cost-effective and worthy of increased logistical challenges. 9,28 Unfortunately, the controversies and implementation barriers in HIV screening have yet to be fully resolved, 29–35 particularly in ED settings where patient volumes exceed capacity and acute stabilization takes precedence over preventive health. 36–38 Screening in the ED for acute HIV infection will be even more challenging than screening for chronic HIV if it entails additional complexity and expense. Motivation to surmount such barriers is likely to be less in regions of lower HIV prevalence, in which disease incidence would also be presumed lower. Improving our understanding of acute HIV epidemiology in ED settings is fundamental for guiding potential implementation of ED screening interventions targeting acute HIV infection. We estimated the seroprevalence of both acute and chronic HIV infection by using a random sample of ED patients from a low-to-moderate HIV prevalence region of the United States.
