Caring for Pregnant Women
The CDC updated its interim guidance for U.S. health care providers caring for pregnant women with possible Zika virus exposure on July 25, 2016, to include the emerging data indicating that Zika virus RNA can be detected for prolonged periods in some pregnant women. To increase the proportion of pregnant women with Zika virus infection who receive a definitive diagnosis, CDC recommends expanding real-time reverse transcription–polymerase chain reaction (rRT-PCR) testing.
Possible exposures to Zika virus include travel to or residence in an area with active Zika virus transmission, or sex with a partner who has traveled to or resides in an area with active Zika virus transmission without using methods to prevent infection.
Testing recommendations for pregnant women with possible Zika virus exposure who report clinical illness consistent with Zika virus disease (symptomatic pregnant women) are the same, regardless of their level of exposure.
- Symptomatic pregnant women who are evaluated <2 weeks after symptom onset should receive serum and urine Zika virus rRT-PCR testing.
- Symptomatic pregnant women who are evaluated 2–12 weeks after symptom onset should first receive a Zika virus immunoglobulin (IgM) antibody test; if the IgM antibody test result is positive or equivocal, serum and urine rRT-PCR testing should be performed.
Testing recommendations for pregnant women with possible Zika virus exposure who do not report clinical illness consistent with Zika virus disease (asymptomatic pregnant women) differ based on the circumstances of possible exposure.
- For asymptomatic pregnant women who live in areas without active Zika virus transmission and who are evaluated <2 weeks after last possible exposure, rRT-PCR testing should be performed.
- If the rRT-PCR result is negative, a Zika virus IgM antibody test should be performed 2–12 weeks after the exposure.
- Asymptomatic pregnant women who do not live in an area with active Zika virus transmission, who are first evaluated 2–12 weeks after their last possible exposure should first receive a Zika virus IgM antibody test.
- If the IgM antibody test result is positive or equivocal, serum and urine rRT-PCR should be performed.
- Asymptomatic pregnant women with ongoing risk for exposure to Zika virus should receive Zika virus IgM antibody testing as part of routine obstetric care during the first and second trimesters.
- Immediate rRT-PCR testing should be performed when IgM antibody test results are positive or equivocal.
This guidance also provides updated recommendations for the clinical management of pregnant women with confirmed or possible Zika virus infection.
Preconception Counseling and Prevention of Sexual Transmission of Zika Virus
The CDC updated its interim guidance for U.S. health care providers on preconception counseling and prevention of sexual transmission of Zika virus for persons with possible Zika virus exposure. The guidance is based on new though limited data. Read the full document on the CDC website: Update: Interim Guidance for Preconception Counseling and Prevention of Sexual Transmission of Zika Virus for Persons with Possible Zika Virus Exposure — United States, September 2016.
- All men with possible Zika virus exposure who are considering attempting conception with their partner, regardless of symptom status, wait to conceive until at least 6 months after symptom onset (if symptomatic) or last possible Zika virus exposure (if asymptomatic).
- Recommendations for women planning to conceive remain unchanged: women with possible Zika virus exposure are recommended to wait to conceive until at least 8 weeks after symptom onset (if symptomatic) or last possible Zika virus exposure (if asymptomatic).
- Couples with possible Zika virus exposure, who are not pregnant and do not plan to become pregnant, who want to minimize their risk for sexual transmission of Zika virus should use a condom or abstain from sex for the same periods for men and women described above.
- Women of reproductive age who have had or anticipate future Zika virus exposure and who do not want to become pregnant should use the most effective contraceptive method that can be used correctly and consistently.
- Possible exposure to Zika virus is defined as travel to or residence in an area of active Zika virus transmission, or sex (vaginal intercourse, anal intercourse, or fellatio) without a condom with a person who traveled to or resided in an area of active transmission.
- Women and men who reside in areas of active Zika virus transmission should talk with their health care provider about attempting conception.
Caring for Infants, Children of Mothers Exposed to Zika
In August 2016, CDC updated the Interim Guidance for the Evaluation and Management of Infants with Possible Congenital Zika Virus Infection. The document includes updated recommendations for the initial laboratory testing and evaluation of infants with possible congenital Zika Virus infection.
Laboratory testing is recommended for:
- Infants born to mothers with laboratory evidence of Zika virus infection during pregnancy
- Infants who have abnormal clinical or neuroimaging findings suggestive of congenital Zika syndrome and a maternal epidemiologic link suggesting possible transmission, regardless of maternal Zika virus test results.
- Lab testing includes rRT-PCR and serologic IgM testing. Initial samples should be collected directly from the infant in the first 2 days of life. If possible, testing of cord blood is not recommended.
- Positive infant serum or urine rRT-PCR test confirms congenital Zika virus infection
- Positive Zika virus IgM with a negative rRT-PCR indicates probable Zika virus infection
Zika virus appears to primarily target neural progenitor cells resulting in cell death and disruption of neuronal proliferation, migration, and differentiation, which slows brain growth and affects neural cell viability.
- Neurologic abnormalities including microcephaly and other neuroimaging findings, hypertonia, hypotonia, spasticity, hyppereflexia, severe irritability, and seizure
- Ocular findings
- Phenotype consistent with fetal brain disruption: severe microcephaly, collapse of the skull, overlapping cranial sutures, prominent occipital bone, redundant scalp and severe neurologic impairment
- Clubfoot and contractures of single or multiple joints presumed secondary to CNS damage
Although Zika virus has been detected in breast milk, no cases of Zika virus infection associated with breastfeeding have been reported, and current evidence suggests that the benefits of breastfeeding outweigh the theoretical risks of Zika virus transmission. All women with Zika virus infection during pregnancy should be encouraged and supported to breastfeed their infants, regardless of infant Zika virus testing results.
CDC updated the recommendations for outpatient management, referral to services, and follow-up of infants with laboratory evidence of congenital Zika virus infection, with or without abnormalities consistent with Congenital Zika Syndrome. The updated recommendations are:
- The updated guidance does not include dengue testing and recommends against testing cord blood specimens.
- The new guidance provides information on how infant laboratory testing results should be interpreted.
- The previous guidance recommended performing a cranial ultrasound unless prenatal ultrasound results from the third trimester demonstrated no abnormalities of the brain. The updated guidance recommends a cranial ultrasound even if the prenatal ultrasound was normal.
- Beyond initial evaluation, the previous guidance only recommended considering an additional hearing screen at 6 months, and evaluating head circumference and developmental milestones throughout the first year of life. The updated guidance provides additional recommendations for the outpatient management of infants through the first year of life.
- The updated guidance emphasizes the importance of establishing a medical home and of providing support for families affected by Zika.
- Repeat eye and hearing assessments and a new recommendation for endocrine (hormonal) evaluation are new in the updated guidance.
In February 2016, the CDC updated Interim Guidelines for Health Care Providers Caring for Infants and Children with Possible Zika Virus Infection and expanded guidelines to include infants and children with possible acute Zika virus disease (2/26/16).
Recommendations for women who reside in areas with ongoing Zika virus transmission, both pregnant women and women of reproductive age, include the following:
- For pregnant women experiencing symptoms consistent with Zika virus disease, testing is recommended at the time of illness.
- For pregnant women not experiencing symptoms consistent with Zika virus disease, testing is recommended when women begin prenatal care. Follow-up testing around the middle of the second trimester of pregnancy is also recommended, because of an ongoing risk of Zika virus exposure. Pregnant women should receive routine prenatal care, including an ultrasound during the second trimester of pregnancy. An additional ultrasound may be performed at the discretion of the health care provider.
- For women of reproductive age, health care providers should discuss strategies to prevent unintended pregnancy, including counseling on family planning and the correct and consistent use of effective contraceptive methods, in the context of the potential risks of Zika virus transmission.
- Pediatric health care providers should work closely with obstetric providers to identify infants whose mothers were potentially infected with Zika virus during pregnancy, and review fetal ultrasounds and maternal testing for Zika virus infection.
Zika virus testing is recommended for:
- Infants with microcephaly or intracranial calcifications born to women who traveled to or resided in an area with Zika virus transmission while pregnant
- Infants born to mothers with positive or inconclusive test results for Zika virus infection. For infants with laboratory evidence of a possible congenital Zika virus infection, additional clinical evaluation and follow-up is recommended.
- Health care providers should contact their state or territorial health department to facilitate testing. As an arboviral disease, Zika virus disease is a nationally notifiable condition.
Protect health care and laboratory workers
Employers and workers in healthcare settings and laboratories should follow good infection control and biosafety practices (including universal precautions) as appropriate, to prevent or minimize the risk of transmission of infectious agents, such as Zika virus. Additionally, employers should ensure that workers:
- Follow workplace standard operating procedures and use the engineering controls and work practices available in the workplace to prevent exposure to blood or other potentially infectious materials.
- Do NOT bend, recap, or remove contaminated needles or other contaminated sharps. Properly dispose of these items in closable, puncture-resistant, leakproof, and labeled or color-coded containers.
- Use sharps with engineered sharps injury protection (SESIP) to avoid sharps-related injuries.
- Report all needlesticks, lacerations, and other exposure incidents to supervisors as soon as possible.
- More details are available from the CDC's "Interim Guidance for Protecting Workers from Occupational Exposure to Zika Virus (4/10/16)" (475 kb, PDF)
Also, all travelers to or residents of areas with ongoing Zika virus transmission should strictly follow measures to prevent mosquito bites.
Additional CDC Resources