In their most recent Morbidity and Mortality Weekly Report (MMWR), the CDC issued interim guidance for Zika Virus testing. From the report:
“On the basis of the newly available data, CDC recommends that Zika virus rRT-PCR be performed on urine collected <14 days after onset of symptoms in patients with suspected Zika virus disease. Zika virus rRT-PCR testing of urine should be performed in conjunction with serum testing if using specimens collected <7 days after symptom onset. A positive result in either specimen type provides evidence of Zika virus infection.”
On April 28th, the FDA granted Emergency Use Authorization to Quest Diagnostics for an RT-PCR test to detect Zika Virus in human samples.
From the press release:
“The test was developed by the reference laboratory business of Quest’s Focus Diagnostics, Inc., subsidiary. The proprietary molecular test is intended for the qualitative detection of RNA from the Zika virus in human serum specimens from certain individuals. Quest Diagnostics plans to make the new test broadly available to physicians for patient testing, including in Puerto Rico, early in the week of May 2.
“Zika Virus RNA Qualitative Real-Time RT-PCR test is a real-time RT-PCR test intended only for the qualitative detection of RNA from the Zika virus in human serum specimens from patients meeting Centers for Disease Control and Prevention (CDC) Zika virus clinical criteria (e.g., clinical signs and symptoms associated with Zika virus infection) and/or CDC Zika virus epidemiological criteria (e.g., history of residence in or travel to a geographic region with active Zika transmission at the time of travel, or other epidemiologic criteria for which Zika virus testing may be indicated ). Testing is limited to qualified laboratories designated by Focus Diagnostics, Inc.
“This test is intended for use by trained clinical laboratory personnel qualified by state and federal regulations who have received specific training on the use of the test in qualified laboratories designated by Focus Diagnostics, Inc., and, in the United States, certified under CLIA to perform high complexity tests.”
According to a recent press release, Rheonix is pursuing a rapid Zika Virus diagnostic test. Lablogatory recently discussed this test with the senior vice president for scientific and clinical affairs at Rheonix.
Lablogatory: I understand this test is a so-called “self-confirming” assay; it corroborates serological results with a molecular confirmation. Can you tell readers a bit about the methodology behind this?
Richard Montagna, PhD, FACB: It works much like the “dual assay” for HIV that we recently developed. Using microfluidics, the sample will be split between two sections of the same cartridge. One section will test for antibodies in a methodology similar to ELIZA. The other section will use LAMP technology to lyse, extract, purify, and amplify Zika-specific RNA sequences.
Lab: Sounds efficient! How long do you anticipate the assay will take to run?
RM: We expect it would take less than an hour to perform. Using our existing equipment base, we anticipate the capacity to perform 24 tests in an hour.
Lab: Given the timeline of the impending outbreak, will you seek Emergency Use Authorization (EUA) from the FDA?
RM: Once development is complete, we’ll discuss EUA with the FDA to determine if that approach is feasible.
From the press release:
The U.S. Food and Drug Administration today announced the availability of an investigational test to screen blood donations for Zika virus. The screening test may be used under an investigational new drug application (IND) for screening donated blood in areas with active mosquito-borne transmission of Zika virus.
Science writer Maryn McKenna has a great write up about the feasibility of keeping mosquito-borne viruses–Zika in particular–out of the US blood supply. You can read about it at her blog Phenomena.
Today NPR featured a write up about how to test for the Zika virus. While It didn’t delve into the diagnostic testing side of things as much as Lab Medicine’s recent podcast, it does give readers a good overview. In addition, it highlights how critical laboratory professionals and pathologists are to public health and infectious disease prevention.
At the end of February, the FDA authorized the emergency use of the CDC’s test for Zika infection. This test is called the CDC Zika IgM Antibody Capture Enzyme-Linked Immunosorbent Assay (Zika MAC-ELISA), and detects antibodies against the Zika virus. This test will be distributed to qualified laboratories that perform high-complexity testing.
For more information, read the FDA and CDC press releases.
Along the same lines, Siemens Healthcare Diagnostics has developed a real-time PCR assay for Zika virus and intends to apply for Emergency Use Authorization for the test in the US, according to GenomeWeb.
Two companies have recently announced development and/or release of Zika virus assay. MD Biosciences has released a rapid assay to detect the virus in human blood and urine samples, and Luminex is partnering with University of São Paulo, Brazil to validate an assay that detects multiple infectious agents, including Zika.
If you’d like to learn more, read the MD Biosciences and GenArraytion press releases.
Edit 3/11/2016: Turns out FDA has something to say about the MD Biosciences test. Read about it in the Minneapolis Star-Tribune.
Dr. Diamond from the Washington University School of Medicine talked with Lab Medicine about all things Zika Virus: a brief history of the virus, modes of transmission, and the implications for laboratory professionals and pathologists.
Give it a listen.