May 31, 2017
- Zika virus testing
- Health Officer changes
Zika Virus Testing
Action requested: Know how to order appropriate Zika virus testing through commercial laboratories.
The Washington State Department of Health has issued the following guidance.
In order to ensure continued testing availability for the highest risk patients and for patients for whom cost is a barrier to testing, testing for Zika virus at the Washington State Public Health Laboratories (PHL) is now limited to:
- Patients for whom cost is a barrier to testing
- Infants with possible congenital exposure to Zika virus
CDC Zika testing criteria must be met and the local health jurisdiction must approve the testing. All infant testing should continue to be performed by PHL.
- All other individuals should be tested using the normal mechanism for obtaining clinical commercial laboratory testing and following the CDC testing algorithm. Local health jurisdiction approval is not required for commercial testing
- Zika virus testing is available through many commercial laboratories, including LabCorp, ARUP, Quest, and Mayo.
- Consult public health for assistance determining whether possible Zika virus exposure occurred, choosing the correct testing algorithm, and following up with patients who test positive. Report suspected Zika virus cases by calling the Snohomish Health District at 425-339-5278.
- Counsel women who are pregnant or planning to become pregnant to avoid travel to areas with Zika virus transmission risk and to avoid unprotected sex with sexual partners who have traveled to areas with CDC Zika travel notices.
- Assess all pregnant women for possible Zika virus exposure at each prenatal care visit. Record travel history and sexual partner travel history at every visit and counsel pregnant women about the risk of Zika virus infection.
- Test every pregnant patient who may have been exposed to Zika virus due to travel to an area with a CDC Zika travel notice, unprotected sex with someone who traveled to an area with a CDC Zika travel notice, or travel to another area with possible Zika transmission risk and development of symptoms consistent with Zika virus disease within 14 days.
- Counsel women with possible Zika virus exposure to wait at least 8 weeks before trying to conceive, or at least 6 months if their male partner also had possible exposure to Zika virus.
If in doubt about whether testing is indicated, or which tests to order, call 425-339-5278.
Testing should only be ordered for persons with symptoms consistent with Zika virus disease and possible exposure, or for pregnant women with possible Zika virus exposure and their infants. Testing should not be used to rule out infection for pre-conception planning.
If a patient meets CDC testing criteria:
- In general, order both an RT-PCR or NAA (on serum and urine) and an IgM ELISA (on serum).
- As the length of time since last travel or sexual exposure or disease onset increases past 14 days, viral RNA in serum and urine declines and RT-PCR or NAA will be less useful. For patients seen >2 weeks after disease onset or last exposure, IgM ELISA should be ordered.
- For pregnant women who test negative in the first two weeks after last travel or sexual exposure, collect a second serum specimen for IgM ELISA between 2-12 weeks after last exposure.
- For patients with symptoms consistent with mosquito-borne disease, dengue and chikungunya testing should also be ordered.
- A negative RT-PCR or NAA test never rules out Zika virus infection; order IgM ELISA on serum.
- A positive IgM ELISA is preliminary evidence of Zika virus infection that should be confirmed by PRNT testing at CDC.
- Laboratories will automatically send IgM positive, equivocal, or inconclusive specimens to CDC for PRNT testing.
- Decisions about clinical management of IgM positive patients should wait for PRNT results.
- If all or part of an exposure period occurred more than 12 weeks prior to specimen collection, infection in asymptomatic pregnant women cannot be ruled out. Call 425-339-5278 for infant testing or testing at the time of delivery.
DOH Zika webpage for Healthcare Providers: http://www.doh.wa.gov/YouandYourFamily/IllnessandDisease/ZikaVirus/healthcareprovidersClinicallabs
CDC Zika webpage for Healthcare Providers: http://www.cdc.gov/zika/hc-providers/index.html
CDC testing algorithms:
Health Officer changes
This is my final health alert to the community, as I will be fully retired from the Snohomish Health District as of June 1. I have served part-time April and May, while the Board of Health sought my successor. As of June 1, Dr. Chris Spitters will serve as interim Health Officer as the recruitment process continues. Should public health issues arise for which you need consultation, please call 425-339-5210.
It has been my privilege to serve Snohomish County residents and health care providers.
Gary Goldbaum, MD, MPH | Health Officer | Administration
3020 Rucker Avenue, Ste 306 | Everett, WA 98201 | 425.339.5210 | email@example.com