Yesterday, the Centers for Disease Control and Prevention (CDC) updated its interim guidance on caring for pregnant women who may have been exposed to the Zika virus. The updated guidance is published online July 24 in Morbidity and Mortality Weekly Report.
“CDC has updated the interim guidance for U.S. health care providers caring for pregnant women with possible Zika virus exposure in response to 1) declining prevalence of Zika virus disease in the World Health Organization’s Region of the Americas (Americas) and 2) emerging evidence indicating prolonged detection of Zika virus immunoglobulin M (IgM) antibodies,” state Titilope Oduyebo, MD, from the Zika Response Team, CDC, and colleagues.
The agency updated the guidance given the fact that it is difficult to accurately interpret the current available tests for Zika, and the fact there is new evidence showing that antibodies to Zika virus can be detected more than 12 weeks after a person is infected.
The CDC kept the definition of possible Zika virus exposure: If a woman has traveled to or is living in an area where mosquitoes carry the virus or is having sex with an individual who has traveled to or lives in such an area.
- Ask all pregnant women in the United States and US territories about possible Zika virus exposure before and during their current pregnancy at every prenatal visit. Providers should also ask about symptoms of Zika (eg, fever, rash, joint pain, conjunctivitis).
- Pregnant women should not travel to areas at risk for Zika transmission. If their sexual partner lives in such an area, pregnant women should use condoms or abstain from sex during pregnancy.
- Pregnant women with recent Zika virus exposure and symptoms of Zika should undergo Zika virus nucleic acid test (NAT) of serum and urine and IgM testing as soon as possible, through 12 weeks after symptom onset.
- For pregnant women without symptoms but with ongoing possible exposure to Zika, IgM testing is no longer routinely recommended; offer Zika NAT testing three times during pregnancy, although optimal timing and frequency of NAT alone are unknown.
- For asymptomatic pregnant women with recent possible Zika exposure, routine Zika testing is not recommended but can be considered using shared-decision making.
- Pregnant women with recent possible Zika exposure whose fetus has ultrasound findings suggesting congenital Zika syndrome should undergo maternal testing with NAT and IgM.
- For nonpregnant women with ongoing Zika exposure, Zika IgM testing is not warranted to establish baseline IgM levels as part of preconception counseling.
The guidance includes an updated comprehensive approach for testing placental and fetal tissues in certain cases, such as in a mother with laboratory-confirmed Zika whose fetus or infant has possible Zika-associated birth defects.