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Measles cases are on the rise globally and here in Illinois the number is increasing as well. Vaccines are 97% effective in preventing this highly contagious disease.  To learn more about this infection and get information on vaccination, go to  Learn how to identify measles and the safe and effective vaccine that can prevent this potentially life-threatening infection for adults and children. 

For Health Care Providers and LHDs

IDPH will test individuals who may have been exposed to Zika virus. This includes people who have:

  • Traveled to a Zika virus affected area 
  • Had sex (oral, vaginal, anal) with a person who has traveled to a Zika virus affected area

Pregnant women who may have been exposed to Zika virus do not need to have symptoms in order to be tested at the IDPH laboratory.

Non-pregnant women and men who may have been exposed to Zika virus may be tested at the IDPH laboratory if they have had at least 1 or more of the below symptoms:

  • Fever
  • Rash
  • Joint pain
  • Conjunctivitis (red eyes)
  • Guillain-Barre Syndrome 

Who To Test

  • Symptomatic pregnant women who may have been exposed to Zika virus
  • Asymptomatic pregnant women who may have been exposed to Zika virus
  • Non-pregnant women and men who may have been exposed to Zika virus and have at least one or more symptoms

To identify patients appropriately for Zika virus testing, gather information on:

  • Pregnancy status
  • Type of exposure and date of exposure
  • Symptoms and date of symptoms onset
  • Travel history
  • Obstetrical information, if available

All tests must be authorized by the local health department prior to submitting to the IDPH laboratory.

What Test to Send

Molecular test for active infection lgM antibody for recent exposure
Distinguishes Zika from Chikungunya and Dengue Can cross react with other flavivirus leading to false positive test
Serum is the preferred specimen for Zika PCR testing. Whole Blood (WB), CSF, Urine, and Amniotic Fluid may be tested only when accompanied by a serum specimen. Amniotic fluid must be paired with a maternal serum specimen. Serum, CSF
Positive test is definitive for Zika Positive or equivocal test requires confirmation by PRNT
Plaque Reduction Neutralization Assay (PRNT)
Confirmatory testing for neutralizing antibody, performed for Zika, Dengue, Chikungunya and West Nile Virus. Performed by CDC on all positive or equivocal Zika MAC-ELISA. Non-diagnostic if both Dengue and Zika pathogen titers are elevated and will be resulted as "Flavivirus infection, specific virus cannot be identified."

Collecting and Submitting Fetal Tissue Specimens for Testing

  • All specimens, for RT-PCR testing, not accompanied by a serum specimen will not be tested by the IDPH laboratory.
  • Specimens should ONLY be sent to CDC from state health departments.
  • Testing should be guided by presence of microcephaly or intracranial calcifications at birth and maternal Zika virus testing results
  • The IDPH Arbovirus Lab Submission form is required.
  • Appropriate consent from the parents or guardian must be obtained
  • To optimize evaluation of possible Zika virus, send fixed tissues
  • Specimen types (products of conception, placenta and fetal membranes, umbilical cord, brain and spinal cord, solid organs), recommended size, gestational age, and preparation instructions are provided in detail at:

How to Test

  1. Identify patient for Zika virus testing and gather information on:
    • Pregnancy status
    • Type of exposure and date of exposure
    • Symptoms and date of symptoms onset
    • Travel history, if applicable
    • Obstetrical information, if applicable
  2. To avoid requiring patients to return for testing, obtain serum and urine samples as soon as Zika virus testing is considered; hold these samples at your office/local laboratory while requesting authorization for testing at the IDPH Laboratory. Do NOT send to the IDPH Laboratory prior to obtaining an authorization number
  3. Check the “Illinois Flowchart: Authorization of Specimens for Zika Virus (ZIKV) Testing” to determine if your patient is eligible for testing at the IDPH Laboratory
    • Consider commercial laboratory Zika virus testing if patient does not meet IDPH Laboratory criteria
    • Call your local health department for guidance as to which test is appropriate. Local health department will provide authorization number
    • Once authorization number is granted, have lab send specimen(s) to IDPH lab (local health department can provide address)
  4. IDPH will fax results to LHDs and providers directly
    • Turn around time for Zika RT-PCR is 2-3 days, Zika IgM is 5-7 days
  5. If reflex Zika IgM or confirmatory PRNT are required, IDPH Laboratory will automatically run these tests or send to CDC
    • Turn around time for PRNT at CDC is 6-8 weeks
  6. Positive Zika IgM test performed by commercial labs should be forwarded to IDPH for confirmatory testing
  7. Negative test from both IDPH and commercial labs may be reviewed by local health department as resources are available to assess whether repeat testing is required.