New technology that transforms a smartphone into a mobile polarised microscope can diagnose malaria in a Rwandan village with the same level of accuracy as a high-tech lab, according to the Texas A&M University biomedical engineers developing the device.
“The way they diagnose malaria now is with a microscope, but it is with a big bench-top microscope that is relatively complicated to use, takes a trained technician, and you have to have the facility for that scope in a centralised lab somewhere. So basically what we are taking is that gold standard and making it into a portable device,” said Professor of Biomedical Engineering, Dr Gerard Coté.
The add-on device, known as a mobile-optical-polarisation imaging device, makes use of a smartphone’s camera features to produce high-resolution images of objects ten times smaller than the thickness of a human hair.
The device images a blood sample using polarised light that can detect Hemozoin crystals, a malaria parasite by-product which appears as very bright dots in the image and is an accurate indicator of infection.
According to the scientists, once the device is attached to the phone, the diagnosis takes just minutes using a phone app.
“An application software would take that image and automatically count the number of red blood cells, count the number of parasites over different fields of view. And then by doing that you can determine if they have malaria or not,” said Dr Coté.
Analysis of a blood sample can be instantaneously made with the patient in the field without the need for a mobile network, says Dr Coté, who notes that a network is only required for transmitting the images to a central location for further analysis or storage.
In 2015 there were around 214 million cases of malaria globally, approximately 438,000 of which were fatal. Ninety percent of these deaths occur in sub-Saharan Africa, according to the WHO.
It’s these stark statistics which inspired the team to keep the device as affordable as possible, to ensure it could be used where it’s needed the most. Smartphones are widely available in Africa and the team says the cost of the add-on optics will be less than $50 with the disposable blood sampling cartridges priced at less than a dollar.