As we saw last year, Ebola is a highly infectious disease that spreads quickly. However, diagnosing the disease, particularly in the field, can take days, which gives it the ability to spread before it's caught.
MIT scientists want to change that and have developed a simple field test that changes color when Ebola-tainted blood comes into contact with it. Not only that, but the test also diagnoses yellow and dengue fevers as well.
Part of the problem with an Ebola outbreak is that current testing procedures require laboratory results, which usually take a few days. In the remote areas greatly stricken by the disease, this can take even longer as those laboratories are farther away. So by the time a diagnosis is made, the patient has already exposed others, spreading the disease and contributing to the outbreak.
MIT's test, however, gives doctors the power to diagnose a patient in just 10 minutes, allowing them to immediately quarantine those individuals who test positive. And it can now diagnose three different diseases, although future versions might allow for more.
MIT's diagnostic device is basically a piece of paper with silver nanoparticles. Doctors take a sample of blood from the patient and apply it to the device. When the viral particles in the blood come across the nanoparticles, each which contains antibodies for that virus, they get caught there and create one of three visible colors, depending on the disease. The test uses a technique called lateral flow technology, similar to what's used in pregnancy tests.
"When we run a patient sample through the strip, if you see an orange band you know they have yellow fever, if it shows up as a red band you know they have Ebola, and if it shows up green then we know that they have dengue," says Kimberly Hamad-Schifferli, a visiting scientist in MIT's Department of Mechanical Engineering.
Not only is the paper strip faster at diagnosing these diseases, but it also requires less blood.
However, MIT scientists stress that this tool complements current testing methods and that it's used in the field as a precursor to further laboratory tests.
"If you're in a situation in the field with no power and no special technologies, if you want to know if a patient has Ebola, this test can tell you very quickly that you might not want to put that patient in a waiting room with other people who might not be infected," says Lee Gehrke, the Hermann L.F. von Helmholtz Professor in MIT's Institute for Medical Engineering and Science (IMES). "That initial triage can be very important from a public health standpoint, and there could be a follow-up test later with PCR or something to confirm."
