Smartphone-enabled device performs vaccine checks on children in developing countries

A smartphone-enabled diagnostic device has been developed that can perform vaccine checks on children in the developing world to check whether they have been immunised against certain deadly diseases.

The device is a collaboration between product development company Cambridge Consultants and Diagnostics For All, a private company that claims to serve a not-for-profit mission by using technology to improve healthcare in the developing world. The two have been working together as part of the Decade of Vaccines Collaboration, an initiative that is attempting to promote coordination across the international development, healthcare and vaccine community.

The simple test is conducted by taking a swab from a child's mouth using a paper-based diagnostic device featuring a QR code. A smartphone app is then used to scan the QR code and perform interrogations that will determine the vaccination status of the child. This data can then be used to either help health workers make informed medical decisions on the ground, or it can be fed back to regional and national databases in order to plan vaccination delivery schemes.
"The elements found in the sample migrate between layers in the paper assay device where they encounter reagents that indicate the presence of the analytes (for immunity to measles and tetanus) by a blue dye," explains David Chastain, programme manager at Cambridge Consultants to Wired.co.uk.
"The camera in the smartphone views the assay device, establishes that the 2D bar code indicates a valid assay within its expiry, makes a colour calibration to compensate for lighting conditions, and measures the intensity of the blue dye in six spots (3 controls to indicate proper function and 3 which indicate assay results)."
One in five children around the world does not receive even very basic vaccines and this results in approximately 1.5million children every year dying from preventable diseases for which vaccines have been developed. The idea behind the device was to facilitate medical support in remote areas where there may not be the facilities or trained staff to administer the tests.
"We needed a low-cost and portable device that could be used in conjunction with our assay to test immunisation in children. The ability to quickly and inexpensively test if a child has already been vaccinated will conserve resources and save many lives in countries around the world. The test is as simple as watching a spot on a postage-stamp-sized piece of paper change colour," said Marcus Lovell Smith, CEO of Diagnostics For All in a statement.

The device could potentially be used in the field within 9-15 months and would cost only a few dollars to implement on the top of the price of the smartphone, says Chastain.