Test Returning Floridians For Both Dengue and Zika Viruses

Zika and dengue virus testing is appropriate for some international travelers
pregnant mom om beach at sunset
North America (Zika News)

The state of Florida health system is being challenged with international travelers returning home infected with either the Zika or Dengue virus. 

As of June 21, 2019, the Florida Health department confirmed 22 travel-related Zika virus cases, including 10 pregnant women. 

And, the Centers for Disease Control and Prevention (CDC) confirmed 25 travel-associated Dengue virus cases on June 5, 2019. 

Since there are no approved treatments or therapeutic vaccines for Zika or dengue, identifying the relevant symptoms is very important. 

Moreover, both of these diseases pose substantial threats to pregnant women and their unborn children, although in different ways. 

Zika symptoms have been linked to serious birth defects, including microcephaly, when contracted by expectant mothers during pregnancy. Microcephaly is a condition in which a baby’s head is significantly smaller than expected, often because their brains have not developed properly. 

While dengue symptoms are not associated with birth defects, it can be transmitted from mother to child during the final week of pregnancy. Previous studies have reported that a dengue infection during pregnancy may be related to preterm birth and low birthweight among infants. 

To assist healthcare providers in better diagnosing these diseases, the CDC published a report on June 14, 2019, that summarizes existing and new guidance on dengue and Zika virus diagnostic testing. 

This new guidance is for patients with a clinically compatible illness, who live in or recently traveled to an area where there is a risk for infection with either of the dengue or Zika viruses. 

The updated CDC recommendations for Zika and dengue virus testing are as follows:

  • Anyone with possible exposure to Zika and dengue virus exposure who has or recently experienced symptoms of Zika or dengue
  • Symptomatic pregnant women with possible Zika or dengue virus exposure
  • Asymptomatic pregnant women with ongoing possible Zika or dengue virus exposure
  • Pregnant women with possible Zika virus exposure who have a fetus with prenatal ultrasound findings consistent with congenital Zika virus infection

Zika testing is not routinely recommended, but may be considered for:

  • Asymptomatic pregnant women who recently traveled with recent possible but no ongoing exposure to Zika or dengue virus

Zika virus testing is not recommended for:

  • Non-pregnant asymptomatic people
  • Preconception screening

For patients with suspected dengue or Zika virus disease, nucleic acid amplification tests are the preferred method of diagnosis.

Immunoglobulin M antibody testing can identify additional infections and remains an important tool for the diagnosis of these diseases.

But, interpreting these test results is complicated by cross-reactivity, and determining the specific timing of infection can be difficult. 

These limitations are a particular challenge for pregnant women in determining whether Zika virus infection occurred during or before pregnancy. 

Gathering information of viruses known to be circulating at the location of exposure should be considered by healthcare providers when deciding which tests to perform and for interpreting the related results. 

Recent Zika news

But, there is some good news regarding Zika tests.

During May 2019, the Food and Drug Administration authorized commercial marketing to consumers of the first diagnostic test for detecting Zika virus antibodies.

The ZIKV Detect 2.0 IgM Capture ELISA is designed to identify proteins (antibodies) produced by the body's immune system when it tests for Zika virus infection in the blood. IgM antibodies indicate an early immune response.