November 21, 2017
Dear Healthcare Provider:

On July 24, 2017, the Centers for Disease Control and Prevention {CDC) issued a Morbidity and Mortality Weekly Report {MMWR) with Interim Guidelines for Healthcare Providers Caring for Pregnant Women with Possible Zika Virus Exposure. It includes changes in testing recommendations that are based, in part, on the decreasing incidence of infection in the Americas, the risk of false positives Zika virus test results, and the prolonged lgM response observed in some patients. This letter summarizes the updated guidance.

Updated Travel Guidance for Pregnant Women

• Pregnant women are still advised not to travel to areas with risk of Zika virus infection. Healthcare providers should continue to ask their patients about travel to or residence in any areas with risk of Zika virus infection or possible sexual exposure to someone with travel to or residence in those areas.

Updated Testing Recommendations for Pregnant Women and Test Results

• The CDC emphasizes shared decision-making based on patient preferences, clinical judgment, and state public health recommendations.
• Pregnant women with possible exposure to areas with risk of Zika virus infection and signs or symptoms consistent with Zika virus disease {e.g., fever, rash, conjunctivitis, arthralgia, or fetal abnormalities on ultrasound that might be related to Zika infection) should be tested concurrently by Zika virus RNA nucleic acid test {NAT) and Zika virus lgM test. The testing window for NAT for pregnant women has been expanded to 12 weeks after onset, so concurrent NAT and lgM testing should be performed up to 12 weeks after onset.
• Asymptomatic pregnant women with ongoing possible exposure {i.e., lives in or frequently travels to an area with risk of Zika virus infection) should be offered Zika virus NAT testing three times during pregnancy. The first test should be performed upon initiation of prenatal care. Zika virus lgM testing is no longer routinely recommended for these asymptomatic pregnant women because of the prolonged lgM response that makes it difficult to differentiate an infection that occurred during the current pregnancy from one that occurred before the current pregnancy.
• For asymptomatic pregnant women with recent possible exposure, but without ongoing exposure, Zika virus testing is no longer routinely recommended because of the decline in the number of cases of Zika virus infection and the concerns for false-positive test results. Testing should be considered on a case-by-case basis using a shared patient­ provider decision-making model that considers patient preferences and clinical judgment.

Healthcare Provider November 21, 2017 Page Two

• As the prevalence of Zika virus disease declines, the likelihood of false-positive test results increases. Before testing for Zika virus, healthcare providers should discuss the limitations of tests and potential risk of misinterpretations of test results, including false-positives and false-negatives. CDC materials for healthcare providers, including patient counseling scripts are available on the CDC website.
• For asymptomatic women who do not have ongoing possible exposure and where the infant or fetus does not have a Zika-related birth defect, placental or fetal tissue testing is not routinely recommended . Placental and fetal tissue may be tested for a fetus or infant with possible Zika virus-related birth defects when Zika virus infection has not been confirmed in the mother.
• The revised testing recommendations for pregnant women will likely impact newborn infant testing because fewer pregnant women with laboratory evidence of Zika virus infection will be identified before the infant’s birth. Therefore, it is important for every infant born to a mother with possible Zika virus exposure to receive a comprehensive physical examination as defined in the CDC revised interim guidance.

On October 19, 2017, CDC released updated Interim Guidance for the Diagnosis, Evaluation, and Management of Infants with Possible Congenital Zika Virus Infection-October 2017.

West Virginia Recommendation for Implementing the Revised CDC Guidance

• Within the updated MMWR, “testing is not recommended for asymptomatic pregnant women with recent possible Zika virus exposure, but without ongoing possible exposure.” The West Virginia Office of Laboratory Services will conduct testing based on a provider’s clinical judgment, an assessment of risks, and expected outcomes. This flexibility in testing asymptomatic pregnant women, as written within the guidance, will be based on Zika virus transmission and other epidemiologic considerations (e.g., seasonality). Thus, we encourage all healthcare providers caring for patients with possible Zika virus exposure to read and familiarize yourself with the clinical guidance.

Thank you for your support during this evolving response to the Zika virus. If you have any questions, please contact the Office of Epidemiology and Prevention Services, Division of Infectious Disease Epidemiology at (304) 558-5358, extension 1; 1 (800) 423-1271, extension 1 (24/7); or the answering service at (304) 925-9946 (24/7).

Sincerely,
Rahul Gupta, MD, MPH, MBA, FACP
Commissioner and State Health Officer

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Amy Tolliver, Director
West Virginia Perinatal Partnership
(304) 558-0530 ext. 5
atolliver@wvperinatal.org