Zika virus

Test information: Zika virus is a mosquito-borne virus. The majority of patients infected with are asymptomatic. However, a small proportion of infections result in a mild, self-limited illness with fever, rash, arthralgia, and conjunctivitis. Infection may be more serious in pregnant women. There is strong scientific consensus that Zika virus is a cause of microcephaly and other congenital malformations in the infant.

The Zika virus testing service is currently not available for individuals who have had no symptoms suggestive of Zika infection. Including:

• Asymptomatic pregnant women who have travelled from Zika-affected countries.
• Asymptomatic returned male travellers whose partners are currently pregnant.
• Asymptomatic returned male and female travellers who are trying to conceive.

Please Note that symptoms such as coryza, cough and/or sore throat suggest upper respiratory tract infection and not Zika virus infection.

More information:

• Zika virus: sample testing advice
• Zika virus infection and pregnancy
• Zika virus algorithm

Specimen Type(s)

• Blood;

Other Acceptable Specimen Type(s)

Venous Blood, Urine, Saliva, Semen, Amniotic Fluid, Tissue.

Specimen Container - Adult

• Gold Top SST BD;

Specimen Container - Paediatric

• Sterile CE-marked Universal Container;

Analytes

• N/A;

Part of a test profile?

No

Volume (min) of sample to be sent to laboratory

Blood 5-10mL, Urine Minimum 1mL

Patient Preparation, Sample Handling and Transport

• Minimum-clotting time 30 minutes.
• Specimens should be transported to the laboratory as soon as possible.
• Outside of normal hours samples should be refrigerated (2 °C to 8 °C).
• Zika virus PCR will be performed on any serum sample taken within 7 days of onset of symptoms suggestive of Zika virus infection, and on any urine, sample taken within 21 days of onset of symptoms suggestive of Zika virus infection.
• Other sample types for PCR testing - saliva, semen, amniotic fluid, and tissue such as placenta or umbilical cord - should only be submitted after individual case discussion with a consultant microbiologist.

Maximum add on time

N/A

Units and Reference Ranges / Interpretation

N/A

UKAS number

9304

UKAS accredited test?

Yes

Comments

Detection of Zika virus RNA in any sample is diagnostic of infection with this virus. If Zika virus RNA is not detected in a patient's samples, this does not exclude previous infection with this virus.

Detection of Zika virus IgM, together with Zika virus IgG, in a serum sample from an individual who has had recent symptoms, will usually suggest recent Zika virus infection.

Detection of Zika virus IgG without IgM, in a serum sample from an individual who has had recent symptoms, will often reflect recent Zika virus infection. This is because Zika virus IgM is frequently not detectable in individuals who have previously had dengue virus infection. Sometimes it is not possible to determine whether a positive Zika virus IgG result (without IgM) is due to recent Zika virus infection, past Zika virus infection, cross-reactivity from another flavivirus infection or non-specific reactivity. In such cases, it is usually appropriate to manage the patient as if they may have had recent Zika virus infection.

If Zika virus antibodies are not detected in a serum sample collected at least 2 weeks after the onset of an acute viral illness featuring fever, rash, arthralgia or conjunctivitis in a pregnant woman, appropriate investigations for alternative infections must be carried out.

If you have any queries about a test or results interpretation please contact us.