September 12, 2003
The four Chicago hospitals with the city's highest HIV-1 prevalence among childbearing-aged women participated in the Mother Infant Rapid Intervention at Delivery (MIRIAD) study. MIRIAD is a multisite study funded by CDC to 1) determine the feasibility of rapid HIV testing in labor and delivery units of women with undocumented HIV status, 2) provide timely therapy to reduce perinatal transmission, and 3) facilitate follow-up care for HIV-infected mothers and their infants. Women eligible for MIRIAD do not have documentation of HIV status in their health-care records and are expected to deliver either during that hospitalization or at >34 weeks' gestational age.
For the MIRIAD study, FDA allowed use of the OraQuick rapid test before its formal licensure. After institutional review board approval, hospital staff were trained to recruit eligible women, obtain informed consent, perform the OraQuick rapid test, and counsel participants about their test results. Three of the four hospitals received approval from their respective point-of-care testing committees for obstetric staff to perform the OraQuick test onsite in labor and delivery units; one hospital sent specimens to its 24-hour laboratory for OraQuick rapid testing. At each hospital, duplicate specimens were sent for standard HIV testing (enzyme immunoassay and, when necessary, Western blot) as part of the study protocol.
Hospital staff performing point-of-care testing in labor and delivery units used timers attached to their clothing to continue other work during the 20 minutes necessary for development of test results. In the hospital in which testing was performed in the laboratory, staff delivered specimens to the laboratory and reported test results to patients when the results were available. Staff recorded the time of each step in the testing protocol. Median times were analyzed by using the Wilcoxon rank-sum test.
During January-July 2002, a total of 5,771 women were evaluated in the labor-and-delivery units of all four hospitals; 514 (9%) were deemed eligible for rapid HIV testing. Of the 514 women, 30 (6%) were not offered participation, 104 (20%) declined participation, and 380 (74%) gave informed consent and were enrolled. A total of 225 women were tested at the three hospitals using point-of-care testing, and 155 were tested at the hospital using laboratory testing. Standard enzyme immunoassay and, when necessary, Western blot testing, confirmed 100% of the rapid test results. Three women were identified as HIV-infected, and antiretroviral therapy was administered to mothers and infants during labor and delivery. None of these infants became HIV-infected.
Turnaround testing time was measured as the time that elapsed between obtaining the participant's blood and the participant receiving the test results. Median turnaround time at the three hospitals using point-of-care testing was 45 minutes (interquartile range: 30 minutes-2.5 hours), substantially less than at the hospital using laboratory testing (median time: 3.5 hours; interquartile range: 94 minutes-16 hours) (p<0.0001).
The findings in this report indicate that point-of-care rapid testing provided valid HIV test results faster than laboratory testing. The median turnaround time for point-of-care testing was less than one fourth that for laboratory testing. With rapid testing, three pregnant women who had not received an HIV diagnosis previously were able to learn their HIV status quickly, resulting in prompt administration of intrapartum and neonatal antiretroviral therapy, measures proven to reduce vertical HIV transmission 3,5,6.
The majority of pregnant women are offered HIV testing early during prenatal care, which is the optimum approach to HIV prevention and care. However, women who do not receive prenatal care are at increased risk for HIV infection3. FDA's approval of the OraQuick rapid test now provides health-care providers with an opportunity to test for HIV infection and inform patients of their HIV status rapidly. This can have a profound benefit for the care of women who have not been tested for HIV during pregnancy. Women can be informed about a negative rapid test result without further testing (pending state-specific regulations). Reactive rapid test results require confirmation but can be used to initiate therapy in this setting.
The findings in this report complement the new CDC initiative aimed at reducing barriers to early diagnosis of HIV infection, which includes a goal to further decrease perinatal HIV transmission in the United States7. Rapid HIV testing of pregnant women not screened during prenatal care will help achieve this goal by increasing the proportion of infected women and their infants receiving intrapartum and neonatal antiretroviral drug prophylaxis. As rapid HIV testing becomes more available in labor and delivery settings, implementation will require training and logistic planning8. FDA waived the OraQuick rapid test under the Clinical Laboratory Improvement Amendments on the basis of the test's simplicity and accuracy.
Data from this study indicate that point-of-care testing was feasible and support using nonlaboratory personnel to perform this rapid test. However, adequate training and quality-assurance procedures are necessary. Point-of-care testing also requires coordination with the laboratory information system to ensure test results are documented correctly. Hospitals will need to assess the costs and benefits of implementing point-of-care HIV testing within their institutions 9,10.
This report is based on data contributed by the following MIRIAD Study principal investigators: S Nesheim, Atlanta, Georgia; MH Cohen, Chicago, Illinois; MJ O'Sullivan, Miami, Florida; R Maupin, New Orleans, Louisiana; and MP Webber, New York, New York. The following persons provided data management and analysis: A Podolanczuk, CORE Center, Chicago, Illinois. S Danner, S Wei, J Wiener, Div of HIV/AIDS Prevention -- Surveillance and Epidemiology, National Center for HIV, STD, and TB Prevention, CDC.