diagnosis statewide: 28% of HIV-infected women in the state were tested through the correctional system. An even higher percentage (39%) of HIV-infected injection drug-using women were identified through the correctional system.
Because reporting of conventional HIV tests takes about one to two weeks, an accurate rapid test, with results available in hours, might have applications in prenatal, labor, and delivery settings to prevent perinatal transmission in some groups of patients (Minkoff and O'Sullivan, 1998). Women and newborns identified with a rapid test late in pregnancy or intrapartum could receive the intrapartum or postpartum component of the ACTG 076 regimen, respectively. A truncated version of the ACTG 076 regimen appears to be effective in reducing perinatal transmission, although to a somewhat lesser extent than the full regimen (see Chapter 4).
While there is one commercially available Food and Drug Administration (FDA) approved rapid test, its rate of false positives is regarded as too high for use in most settings, though it may be beneficial in settings of high-prevalence (CDC, 1998g). The CDC is currently developing guidelines on the implementation and quality assurance of rapid HIV testing. New rapid tests are expected to become commercially available in the near future and, when used in conjunction with existing rapid tests, would have lower false positive rates.
In the prenatal setting, a rapid test might be especially valuable for women who are unlikely to return for test results. According to the committee's site visits and workshops, these women are more likely to be adolescents, drug users, undocumented immigrants, and/or homeless. In the labor and delivery setting, a rapid test might be valuable for women who have not been tested previously or have not received prenatal care. There is a higher prevalence of HIV infection in women who have not received prenatal care (Lindsay et al., 1991c; see also Chapter 6). The labor and delivery setting offers the last opportunity to interrupt HIV transmission via administration of intrapartum therapy and advice to avoid breast-feeding. Since this is not an ideal time to obtain consent to testing and to discuss the implications of a positive result, program design and implementation would need to address these issues.
Bellevue Hospital Center in New York City has applied for permission from the state department of health to launch a voluntary, rapid testing demonstration program (as an alternative to the mandatory newborn testing program). Under this program, all women in labor and delivery who previously have not been tested for HIV will be offered a test. Since women who do not agree to prenatal testing at this public hospital are considered to be a population with higher HIV prevalence, the positive predictive value of a test is higher than in other settings. When the test is positive, antiretroviral therapy is to be offered beginning immediately in the intrapartum period, even though the woman's status must be confirmed by more definitive tests.