Zika Testing

The right Zika test for you depends on how long ago you had symptoms or were possibly exposed to Zika, and whether or not you are pregnant. Not everyone who might be exposed to Zika needs to be tested.

Kinds of Zika virus tests

1) RNA NAT Tests are done within 2 weeks of when symptoms start or possible exposure to Zika virus (through travel or sex).

RNA Nucleic Acid Testing (RNA NAT) looks for Zika virus, usually in blood or urine. The Trioplex Real-time Reverse Transcription Polymerase Chain Reaction (Trioplex rRT-PCR) can detect Zika virus as well as dengue and chikungunya viruses.

Who can have RNA NAT testing for Zika virus?

  • Anyone with symptoms of Zika virus that started within the last two weeks
  • Pregnant women with or without symptoms who traveled to places with Zika—or had sex with a partner who lives in or traveled to an area with Zika—within the last two weeks
  • Any pregnant women who has had a positive antibody test for Zika virus (see below)

What do my results mean?

  • A positive RNA NAT test for Zika means that you have Zika virus, and no other testing is needed.
  • A negative result doesn’t necessarily mean that you don’t have Zika virus; it might just mean that the virus is no longer detectable in your body. You should still have antibody testing to try and rule out Zika virus.

2) Antibody Tests (also called serological tests) are done 2-12 weeks after symptoms start or after last possible exposure to Zika virus (through travel or sex).

If you recently had Zika virus, your body will produce antibodies against Zika. If you didn’t have Zika virus, you will not produce Zika antibodies. The Zika IgM Antibody Capture Enzyme-Linked Immunosorbent Assay (Zika MAC-ELISA) looks for Zika virus antibodies in blood or in fluid taken from the spinal column (cerebrospinal fluid).

Who can have antibody testing for Zika virus?

  • Anyone who might have been exposed to Zika virus (through travel or sex) and had symptoms of Zika virus within the last 2-12 weeks
  • Pregnant women with or without symptoms who traveled to places with Zika—or had sex with a partner who lives in or traveled to an area with Zika—within the last 2-12 weeks
  • Pregnant women who live in places with active Zika virus transmission might have this testing as a routine part of their pregnancy care in the 1st and 2nd trimesters

What do my results mean?

  • A negative Zika antibody test means there is no evidence of Zika virus infection and no need for further testing.
  • A positive or unclear antibody test result will be confirmed by another test called a Plaque Reduction Neutralization Test (PRNT). The PRNT test tells if the antibodies you have are actually from Zika virus, or if they are from another related virus, such as dengue.
Not everyone needs to have Zika virus testing

Testing is not recommended for men without symptoms or non-pregnant women without symptoms, even if they might have been exposed to Zika through travel or sex.

Testing is not the best way to know if you could pass the virus to someone else through sex. If you might have been exposed, you should take steps to prevent passing Zika to someone else (see How to Prevent Getting or Spreading the Zika Virus).

These charts can help healthcare providers decide who qualifies for testing and what testing is best:
https://www.cdc.gov/zika/pdfs/algorithm-for-us-testing-of-symptomatic-individuals.pdf
https://www.cdc.gov/zika/pdfs/algorithm-for-us-testing-of-symptomatic-individuals-chart-2.pdf
https://www.cdc.gov/zika/pdfs/algorithm-for-us-testing-of-symptomatic-individuals-chart-3.pdf

How to get tested for Zika virus

The Centers for Disease Control and Prevention (CDC), along with state and local health departments, are testing for Zika virus. Your health care provider can contact your state or local health department for testing information.

Some private labs also offer Zika testing. Information on the specific testing, time to results, forms and who qualifies for testing can be found on the companies’ websites including:

LabCorp
Mayo Clinic
Quest