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Collecting & Submitting Placental and Fetal Tissue Specimens for Zika Virus Testing

General Information

Collection and Submission of Fetal Tissues for Zika Virus Testing

Collection and Submission of Fetal Tissues for Zika Virus Testing

The following information applies to fetal tissue collection and submission. For cord blood and amniotic fluid analysis, please see Collecting and Submitting Body Fluid Specimens for Zika Virus Testing.

IMPORTANT: Pre-approval is required prior to submission of any tissue specimens. For pre-approval please contact and

Health Care Providers
  1. Please make sure that your state, territorial, tribal, or local health department has been notified and has received pre- approval from CDC for submission and shipment of specimens before they are collected and sent.
    • Institutions with surgical pathology available: Please consult surgical pathology regarding appropriate collection and processing of specimens for Zika virus testing.
    • Institutions without surgical pathology available: Please see table below for general guide on collection of tissue specimens for Zika virus testing.
    • Specimens should ONLY be sent to CDC from health departments.
Health Departments
  1. Pre-approval is required prior to the submission of specimens to CDC. Information required for the pre-approval process includes:
    • Maternal/neonatal state and specimen identification numbers, maternal age, Zika virus test results, travel locations and dates, illness onset (if applicable), estimated date of delivery, gestational age at delivery, pregnancy outcome, age and sex of infant, birth anthropometric measurements, any additional testing/imaging.
    • Please specify cases that have been reported to the US Zika Pregnancy Registry and for which this information has already been provided during the pre-approval process.
  2. Please Note: CDC Form 50.34 is required to be submitted with all specimens. One hardcopy (per case) of the CDC 50.34 form should be submitted with the formalin-fixed wet tissues or formalin-fixed paraffin-embedded tissue blocks at ambient temperature.
    • Select Test Order Code CDC-10365 “Pathologic Evaluation of Tissues for Possible Infectious Etiologies."
    • Select “Zika Virus” as the suspect agent from the drop down menu.
    • The remaining items must be completed electronically and then printed.
Collection of Fetal or Neonatal Tissues
  1. Appropriate consent from the parents or guardian must be obtained by the healthcare provider prior to collection and submission of specimens for Zika virus testing.
  2. To optimize evaluation of possible Zika virus infection in fetal tissues, send fixed tissues. Submission of frozen tissues may be considered on a case by case basis, please email and for consultation.
  3. The type of tissues available for evaluation will depend on the gestational age of the fetus and the collection procedure that is performed. Effort should be made to maintain the tissue architecture, and to minimize any dissection or disruption of the tissues.
  4. For situations in which individual organs or tissue types cannot be identified, please provide any available tissue with minimal disruption.
  5. CDC Infectious Diseases Pathology Branch (IDPB) accepts microscopic or gross photos from health departments as part of either telediagnosis consultation or routine tissue specimen submission for diagnostic evaluation. Photos should not contain patient names or medical record numbers. Visit the CDC ePathology telediagnosis page for more details.
  6. Staff who collect and handle specimens should refer to Zika biosafety guidelines for laboratory and pathology procedures.
Specimen Type Fixed Specimens When to Consider General Notes
Products of conception (POC)
  • 4 or more specimens
  • Generally less than 12wks gestational age
  • For early pregnancy loss/miscarriage, please send POCs fixed in formalin.
Placenta and fetal membranes
  • Several full thickness pieces including at least 3 full thickness pieces (0.5–1 cm x 3–4 cm in depth) from middle third of placental disk and at least 1 from the placental disk margin
  • One 5 x 12 cm strip of fetal membranes
  • Any gestation for which placenta is available
  • Please include sections of the placental disk, fetal membranes, and pathologic lesions when possible.
  • Please include information about placenta weight and sample both maternal and fetal side of the placenta.
  • Label all specimens to identify location of sample.
Umbilical cord
  • 2.5 cm segments of cord
  • 4 or more specimens
  • Any gestation for which placenta is available
  • Umbilical cord segments should be obtained proximal, middle, and distal to umbilical cord insertion site on the placenta.
  • Label all specimens to identify location of sample.
Brain and spinal cord
  • 0.5–1.0 cm3 each
  • 5 or more specimens from different parts of brain and spinal cord
  • Fetal demise
  • It is critical to maintain the tissue architecture to evaluate viral pathology. Certain fetal tissues require longer fixation, please fix brain specimens for 48-72 hours.
Solid organ (heart, lung, liver, kidneys, skeletal muscle, eyes, bone marrow)
  • 0.5-1.0 cm3
  • 1 representative specimen from each solid organ
  • Fetal demise
  • Submission of eyes is highly recommended.
Fixed Tissues
  1. Histopathology, immunohistochemical staining, and RNA nucleic acid testing (NAT) will be performed on fixed tissues, as needed. Fixed tissues may include formalin fixed and/or paraffin embedded tissues.
  2. The volume of formalin used to fix tissues should be 10x the volume of tissue. Place tissue in 10% buffered formalin for a minimum of three days or until fully fixed. After fixation, tissue can be transferred to 70% ethanol for long term storage.
  3. If stored prior to shipping, please transfer fixed tissues to 70% ethanol after 72 hours.
  4. Fixed tissues should be stored and shipped at room temperature. Additional instructions for collecting, handling, and shipping formalin-fixed tissues are also available. Paraffin blocks should be submitted in accordance with these instructions for formalin-fixed specimens.
  5. DO NOT FREEZE samples that have been fixed in formalin.
Submission and Shipping of Specimens
  1. CDC Form 50.34 is required with all specimen submissions and specimens should ONLY be sent to CDC directly from health departments. Please see introduction above for further details.
  2. Fixed specimens can be shipped at ambient temperature to:

Infectious Diseases Pathology Branch
Centers for Disease Control and Prevention
1600 Clifton Rd. NE, MS G-32
Atlanta GA 30329-4027

  1. More information on shipping can be found in the Guidelines for Specimen Submission for Pathologic Evaluation of CNS Infections .
Reporting of Results
  1. Test results will be reported to the state health department and the submitting healthcare provider.
  2. Turnaround time will vary, depending on testing volume.
  3. Considerations for interpreting pathology results include maternal/infant epidemiologic risk factors, maternal/infant Zika testing results, and clinical presentation. For assistance with interpretation of pathology reports results please contact