Rapid Colorimetric Detection of Zika Virus from Serum and Urine Specimens by RT-LAMP (Reverse Transcription Loop-Mediated Isothermal Amplification).

The Zika virus (ZIKV) can be passed from a pregnant woman to her fetus. Resulting infection by this virus can cause early miscarriage and a pattern of severe birth defects in fetuses and infants. Therefore, a rapid diagnostic assay that can be performed throughout pregnancy in a clinical setting is vital for prenatal care of women living in areas where this virus may be transmitted.

CDC has developed a RT-LAMP assay for the rapid screening of ZIKV RNA from urine and serum. As few as 10 copies of ZIKV RNA per microliter can be detected using this assay, showing that it is highly sensitive. It was also shown to be highly specific for ZIKV RNA when tested against a panel of urine samples spiked with other flaviviruses such as dengue virus sub-types 1-4, West Nile virus, St. Louis encephalitis virus, and chikungunya virus, most viruses that circulate in the same geographic regions as ZIKV. This assay offers a rapid, reliable, sensitive, and specific means to detect ZIKV that can be performed in a clinical point-of-care (POC) or field setting with minimal equipment and technological expertise. The assay is fast to set up and perform (total time 1 hour). Additionally, it is approximately as sensitive and specific as RT-PCR detection methods. Thus far, 178 clinical samples collected from the 2015/2016 Zika virus outbreak were tested using this assay. CDC is currently working with a group to test a prototype point of care (POC) test in a clinical setting and develop a POC.