Test Catalog

Interpretive Handbook

Test 60356 :
HIV-2 Antibody Screen, Serum

Clinical Information Discusses physiology, pathophysiology, and general clinical aspects, as they relate to a laboratory test

Epidemiologic data suggest that AIDS is caused by at least 2 types of HIV, HIV-1 and HIV-2. HIV-1 has been isolated from patients with AIDS and asymptomatic infected individuals. The closely related HIV-2 was first isolated from patients in West Africa in 1986, and the first case of AIDS due to HIV-2 in a patient was reported in the United States in 1988. HIV-2 appears to be endemic only in West Africa, but HIV-2 also has been identified in individuals who have lived in West Africa or had sexual relations with individuals from that region. HIV-2 infection is rare in the United States (<100 cases reported to date); most of the reported cases are from the northeastern states and involve persons from West Africa.


Both HIV-1 and HIV-2 are transmitted by sexual contact, sharing contaminated needles, exposure to infected blood or blood products, or from an infected mother to her fetus or infant. During the course of HIV-2 infection, antibodies are formed against the viral proteins p26 and gp34. Immunosuppressed patients may fail to develop these antibodies. At-risk patients with reactive results for HIV-1/-2 antigen and antibody combination assays and indeterminate or negative results for HIV-1 antibodies by supplemental testing should be investigated for the presence of HIV-2 antibodies.

Useful For Suggests clinical disorders or settings where the test may be helpful

Screening for and detection of HIV-2 antibodies in asymptomatic individuals

Interpretation Provides information to assist in interpretation of the test results

Reactive screening test results suggest the presence of HIV-2 antibodies. All repeatedly reactive serum specimens are automatically confirmed by an HIV-2 antibody confirmation assay with an additional charge. 


Negative screen results indicate the absence of HIV-2 antibodies. These results should be interpreted with caution in patients who are at high risk or have symptoms or signs of HIV infection.

Cautions Discusses conditions that may cause diagnostic confusion, including improper specimen collection and handling, inappropriate test selection, and interfering substances

This test is not offered as a screening or confirmatory test for blood donor specimens.


This test is not offered for maternal/newborn HIV screening for specimens originating in New York.


All results that are reactive by HIV-2 antibody screening test and positive by confirmatory test should be verified by testing second serum specimens. Positive confirmatory HIV-2 antibody test results are required by statute in most states to be reported to the state departments of health for surveillance of communicable diseases.


False-reactive HIV-2 antibody screening test results may occur in patients with HIV-1 infection due to cross-reactivity of HIV-1 antibodies with the viral core and polymerase proteins used in the HIV-2 antibody screening tests.


Patients at risk for HIV-2 infection and suspected to have acute HIV-2 infection may have a) negative HIV-2 antibody screen results, or b) repeatedly reactive HIV-2 antibody screen results but negative or indeterminate confirmatory test results. For such patients, testing for HIV-2 DNA or RNA (FHV2Q / HIV-2 DNA/RNA Qualitative Real-Time PCR) is recommended.


Assay performance characteristics have not been established for the following types of serum specimen:

-Grossly icteric (total bilirubin level of >20 mg/dL)

-Grossly lipemic (triolein level of >3,000 mg/dL)

-Grossly hemolyzed (hemoglobin level of >500 mg/dL)

-Cadaveric specimens

-Presence of particulate matter

Reference Values Describes reference intervals and additional information for interpretation of test results. May include intervals based on age and sex when appropriate. Intervals are Mayo-derived, unless otherwise designated. If an interpretive report is provided, the reference value field will state this.


See HIV Serologic Interpretive Guide in Special Instructions for further interpretive information.

Clinical References Provides recommendations for further in-depth reading of a clinical nature

1. Constantine N: HIV antibody assays May 2006. In HIV InSite Knowledge Base (online textbook). Available at: http://hivinsite.ucsf.edu/InSite?page=kb-00&doc=kb-02-02-01

2. Centers for Disease Control and Prevention and Association of Public Health Laboratories. Laboratory testing for the diagnosis of HIV infection: Updated recommendations. June 27, 2014. Available at: http://stacks.cdc.gov/view/cdc/23447

3. Hariri S, McKenna MT: Epidemiology of human immunodeficiency virus in the United States. Clin Microbiol Rev 2007;20:478-488

4. Owen SM, Yang C, Spira T, et al: Alternative algorithms for human immunodeficiency virus infection diagnosis using tests that are licensed in the United States. J Clin Microbiol 2008;46:1588-1595