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Centers
for Disease Control and Prevention (CDC)
Atlanta, GA 30333
April 22, 2003 |
Dear Colleague:
The prevention
of perinatal HIV transmission requires routine HIV screening of all
pregnant women1 and the use of appropriate antiretroviral
and obstetrical interventions that begin during pregnancy. Together,
these actions can reduce the rate of mother-to-child HIV transmission
to 2 percent or lower. Recently, new data have emerged indicating that
higher testing rates are associated with testing strategies that routinely
incorporate HIV tests in the standard battery of tests for all pregnant
women. In light of this information, the Centers for Disease Control
and Prevention (CDC) recommends that HIV testing be a routine screening
procedure. CDC also recommends implementing rapid HIV testing in postnatal
settings for infants of women not tested prenatally. Considering the
potential for preventing transmission, no child should be born in this
country whose HIV status, or whose mother’s status, is unknown.
CDC published data on recent prenatal HIV testing rates in the United
States and Canada in the Morbidity and Mortality Weekly Report
(MMWR) of November 15, 2002.2 This study examined HIV prenatal testing rates
associated with three different prenatal testing approaches from data
gathered from 16 states and 5 Canadian provinces. A brief description
of the testing approaches and data findings follows:
- “Opt-in”: Pregnant women receive pre-HIV test counseling
and must specifically consent to an HIV antibody test, usually in writing.
This is the most common prenatal HIV testing approach in the United
States3. Among eight states using the “opt-in” approach
where data were collected from medical records for 1998–1999,
testing rates ranged from 25 percent to 69 percent. Canadian testing
rates in three “opt-in” provinces ranged from 54 percent
to 83 percent.
- “Opt-out”:
Pregnant women are notified that an HIV test will be routinely included
in the standard battery of prenatal
tests for all pregnant women, but they can decline HIV testing. Currently,
Arkansas, Michigan, Tennessee, and Texas have adopted some version
of this approach.3 In Tennessee, where this approach was used, a testing
rate of 85 percent was reported. Two Canadian provinces using this
approach showed a testing rate of 98 percent and 94 percent.
- Mandatory
newborn screening: If the mother’s HIV status is
unknown at delivery, newborns are tested for maternal HIV-antibody,
with or without the mother’s consent. Results must be available
within 48 hours of testing. Connecticut and New York have implemented
these approaches (in combination with an opt-in approach for pregnant women). In these two states, data indicate that prenatal testing rates
rose from 52 percent to 83 percent in a seven-county area of New
York, and from 31 percent to 81 percent in Connecticut, during the
periods just before and just after implementation of mandatory newborn
testing. In 2001, New York reported a statewide prenatal HIV testing
rate of 93 percent based on newborn metabolic screening of all live
births.
Prenatal HIV Screening
Based on information presented
in the MMWR, the available data indicate that both “opt-out” prenatal maternal screening and mandatory
newborn screening achieve higher maternal screening rates than “opt-in” prenatal
screening. Accordingly, CDC recommends that clinicians routinely screen
all pregnant women for HIV infection, using an “opt-out” approach,
and that jurisdictions with statutory barriers to such routine prenatal
screening consider revising them.
Newborn HIV Screening
In addition, CDC
encourages clinicians to test for HIV any newborn whose mother’s
HIV status is unknown. Jurisdictions should consider whether a mandatory
screening policy for these infants is the best
way to achieve such routine screening. Data demonstrate that detection
of HIV infection during pregnancy through HIV testing of all pregnant
women affords the best opportunity to deliver interventions when they
are most efficacious. When intervention does not begin until the intrapartum
or neonatal periods, 9 percent to 13 percent transmission rates are
achievable based on clinical trial and observational data.4,5 Recent
experience from the CDC-funded Mother-Infant Rapid Intervention at
Delivery (MIRIAD) study indicates that HIV rapid testing of women can
be done during labor, and that antiretroviral interventions can be
quickly delivered to HIV-infected mothers and their infants. Therefore,
for those women whose HIV status is unknown at labor, CDC recommends
routine, rapid testing. When the mother’s HIV status is unknown
prior to the onset of labor and rapid HIV testing is not done during
labor, CDC recommends rapid testing of the infant immediately post-partum,
so that antiretroviral prophylaxis can be offered to HIV-exposed infants.
The federal Food
and Drug Administration has approved three rapid HIV test kits (SUDSTM,
OraquickTM,
and RevealTM), which can be used at delivery.6 When rapid test results
are positive, antiretroviral
interventions can be offered to the mother intrapartum and to her infant
based on the preliminary results. Confirmatory testing should occur
as soon as possible after delivery.
Sincerely,
Julie Louise Gerberding, M.D., M.P.H.
Director |
Harold W. Jaffe, M.D.
Director
National Center for HIV, STD, and
TB Prevention |
References
1CDC.
Revised recommendations for HIV screening of pregnant women. MMWR 2001; 50(RR-19):59-86.
2CDC.
HIV testing among pregnant women – United States and Canada,
1998-2001. MMWR 2002;51:1013-16.
3American
College of Obstetricians and Gynecologists. Survey of state laws
on HIV and pregnant women, 1999-2000. Moore KG, ed. Washington,
DC:American College
of Obstetrician and Gynecologists, 2000.
4Wade
NA, Birkhead GS, Warren BL et al. Abbreviated regimen of zidovudine
prophylaxis and perinatal transmission of the human immunodeficiency
virus.
N Engl J Med
1998;339:1409-14.
5Guay
LA, Musoke P, Fleming T, et al. Intrapartum and neonatal single-dose
nevirapine compared with zidovudine for prevention of mother-to-child
transmission
of HIV-1
in Kampala, Uganda: HIVNET 012 randomised trial. Lancet 1999;354:795-802.
6CDC.
Notice to readers: Approval of new rapid test for HIV antibodies. MMWR 2002; 51:1051-2.
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