The Centers for Disease Control and Prevention (CDC) listed more than 5,000 cases of the Zika virus in the U.S. from January 2015 to February 2017. The vast majority of those cases were travelers returning from affected areas. Florida has the highest number of cases of the Zika virus at 1,069 reported cases, with 214 cases acquired through presumed local mosquito-borne transmission.
The Zika virus, transmitted to humans through the bite of an infected Aedes aegypti mosquito, is especially dangerous for pregnant women, and is linked to several severe birth defects transferred to the fetus including microcephaly, a condition in which a baby is born with a small head or the head stops growing after birth.
Currently, patients are diagnosed by testing whether they have antibodies against the Zika virus in their bloodstream; however, the antibody test cannot discriminate accurately between the Zika virus and other flaviviruses such as Dengue, West Nile virus, and Chikungunya. The more accurate method for detecting the virus is by looking for pieces of the viral genome in a patient’s blood sample using a test known as polymerase chain reaction (PCR), which is costly ($20,000+), bulky, and requires highly skilled laboratory personnel to operate. Furthermore, results for PCR testing can take hours to yield results.
A device, about the size of a tablet computer, was developed that can be used in environments such as a busy airport or even a remote location in South America, using just a saliva sample.
The diagnostic tool could reduce the impact of the outbreak until a vaccine is identified. The tool can be used without expensive laboratory equipment and skilled technicians to provide reassurance to expectant families and those concerned because of recent travel. The device would cost approximately $2, and could accurately determine within 15 minutes whether a person has an active infection.
This new device is based on technology developed to detect HIV. It uses inexpensive paper- or plastic-based materials, a cassette-sized container holding up to 12 samples at a time, and a receptacle about the size of a tablet. The materials are easy to make, easy to use, and can easily and safely be disposed of by burning, providing an appealing strategy for developing an affordable tool for diagnosing the Zika virus in developing countries, as well as low- and middle-income countries where there is limited laboratory infrastructure.