ACOG, SMFM issue recommendations for Zika prevention, management

The American College of Obstetricians and Gynecologists and the Society for Maternal-Fetal Medicine have released a practice advisory that "represents the current information available regarding Zika."

The advisory details various aspects of Zika prevention and management, such as travel restrictions, reproductive counseling and care of pregnant and postpartum women.

"It is not known if pregnant women are at greater risk of Zika virus transmission than non-pregnant individuals," the organizations wrote. "However, there is demonstrated causation between Zika virus infection during pregnancy and adverse pregnancy outcomes such as pregnancy loss, microcephaly, and other brain and eye abnormalities. Transmission of Zika to the fetus has been documented in all trimesters; Zika virus RNA has been detected in fetal tissue from early missed abortions, amniotic fluid, term neonates, and the placenta. However, much is not yet known about Zika virus in pregnancy. Uncertainties include the incidence of Zika infection among pregnant women in areas of Zika virus transmission, the rate of vertical transmission, and the rate with which infected fetuses manifest complications such as microcephaly or demise."

They cited two studies that reported a possibility of microcephaly in 1% to 13% of babies whose mothers were infected in the first trimester and outcomes including microcephaly, growth restriction and stillbirth in 29% of fetuses from all trimesters.

Travel restrictions

Pregnant women should avoid areas with active Zika outbreaks, such as Puerto Rico, some areas in Florida and other countries, the organizations stated. Lists are available via the CDC.

Prevention

Heath care providers should inform patients about using EPA-approve insect repellants, staying in screened or air-conditioned areas and covering skin. In addition, they should urge patients to use products with DEET or permethrin, which are both safe during pregnancy.

Reproductive counseling

“Obstetrician–gynecologists and other health care providers should discuss pregnancy intentions and reproductive options with all women of reproductive age for shared decision making,” ACOG and SMFM stated. “In the context of the ongoing Zika outbreak, preconception care should include a discussion of the signs and symptoms and the potential risks of Zika virus infection. Health care providers should discuss their patients’ reproductive life plans in the context of potential Zika virus exposure.”

Noting reports of sexual transmission, the organizations urged the use of male condoms, female condoms and dental dams. They recommended that pregnant women with partners at risk for infection consistently use protection or consider abstaining during pregnancy.

Before attempting to conceive, women should wait at least 8 weeks from symptom onset or exposure and men should wait at least 6 months from symptom onset.

Management of pregnant and postpartum patients

The organizations cited interim guidance issued by the CDC which detailed testing procedures for symptomatic and asymptomatic women.

Symptomatic women being tested less than 2 weeks after onset or asymptomatic women who are not living in an area with active Zika being tested less than 2 weeks after positive exposure should have serum and urine tested by rRT-PCR. If those results are negative, symptomatic women should have dengue virus IgM antibody testing and Zika virus IgM testing. If either test is positive, plaque reduction neutralization testing (PRNT) should be done on the same sample in order to rule out false-positive results.

Symptomatic women being tested between 2 and 12 weeks after onset, asymptomatic women who are not living in an area with active Zika being tested between 2 and 12 weeks after exposure, and asymptomatic women living in an area with active Zika should receive Zika virus and dengue virus IgM antibody testing. If the dengue test is positive, PRNT should be performed. If the Zika virus test is positive or equivocal, patients should receive reflex Zika virus rRT-PCR serum and urine testing. If the rRt-PCR test is negative, PRNT should be performed.

“The many uncertainties about Zika virus biology highlight the challenges of managing and counseling about exposures and infection in pregnancy,” the organizations wrote. “Referral to a maternal–fetal medicine or infectious disease specialist with expertise in pregnancy management is recommended and may be useful particularly for those pregnancies with demonstrated maternal infection or concerning fetal findings.”

They continued: “Given that serology test results can be difficult to interpret, particularly in persons who were previously infected with or vaccinated against flaviviruses, and because of the adverse outcomes caused by Zika virus infection during pregnancy are not fully described, pregnant women with laboratory evidence of recent flavivirus infection are considered to have possible Zika virus infection and should be monitored frequently.”

Based on the CDC guidelines, ACOG and SMFM stated that ultrasounds should be performed every 3 to 4 weeks to evaluate fetal growth and anatomy in pregnant women with a recent Zika virus infection, when Zika virus infection is presumed and in cases when a specific virus cannot be identified.

“Ultrasound examinations should be used to assess fetal anatomy, particularly neuroanatomy, and to monitor growth,” the wrote. “They should focus on development of findings such as intracranial calcifications, microcephaly, ventriculomegaly, arthrogryposis; abnormalities of the corpus callosum, cerebrum, cerebellum, and eyes; and other brain abnormalities, as those abnormalities have been most frequently reported in affected pregnancies.”

Amniocentesis consideration should be individualized to each patient, as evidence has not proven its ability in diagnosing congenital Zika virus.

In cases of fetal losses, rRT-PCR and immunohistochemical staining of tissue is recommended.

In cases of live births, the agency recommends testing infant serum and cord blood using rRT-PCR as well as Zika IgM and dengue virus IgM antibodies. Cerebrospinal fluid can be tested if it has been collected for another reason. Zika virus rRT-PCR and immunohistochemical staining of the placenta and the umbilical cord are also recommended.

ACOG and SMFM also found that “the benefits of breastfeeding likely outweigh the potential neonatal risks” of transmitting Zika.

Reporting via the pregnancy registry

The organizations also detailed the process in participating in the US Zika Pregnancy Registry.

“Obstetrician–gynecologists will need to report pregnant women with any laboratory evidence of Zika virus infection (positive or inconclusive test results) as well as any adverse outcomes to the state health department. They can expect follow up from health officials during the pregnancy and at the time of expected birth to collect surveillance data. CDC registry staff will work with state health departments to assist with collection of information. Ob-gyns can also contact the CDC pregnancy hotline (call 770-488-7100 or email ZikaPregnancy@cdc.gov) to discuss women with laboratory evidence of Zika virus infection. If they contact CDC for clinical consultation, registry staff will ensure that state, tribal, local, or territorial health departments are notified.

Infection control

Noting the presence of Zika virus RNA in various body fluids, ACOG and SMFM recommended use of Standard Precautions in health care settings.

“Adherence to Standard Precautions, the basic infection prevention measures that apply to patient care in all heath care settings, is necessary to protect health care providers and patients in labor and delivery settings from transmission of Zika virus, as well as blood-borne pathogens, such as HIV and hepatitis C,” they stated. “The appropriate use of personal protective equipment is important for all health care providers to minimize the risk of transmission of infectious pathogens through exposure to blood and body fluids. There is no evidence that contact precautions or respiratory isolation of Zika virus-infected patients is warranted.” – by Chelsea Frajerman Pardes