A terrible scourge in the developing world, anemia claims hundreds of thousands of lives every year. Medical tests to detect the condition and prevent tragedy are often unavailable, but students at John Hopkins University have invented a sensor that turns a cell phone into an inexpensive blood analysis tool. At an awards ceremony in Seattle on July 14, the bioengineernig undergraduates revealed their device, the HemoGlobe, which will soon be undergoing testing in Africa.
Anemia is a condition where the red corpuscles in the blood are either unhealthy or there are too few of them. Because of this, the body cannot transport enough oxygen to the tissues, causing illness and even death. There are any number of causes of anemia - blood loss, congenital illness, parasites, radiation, cancer, vitamin deficiencies or a simple lack of iron in the diet can all contribute. It’s particularly hard on women in the developing world, where over 100,000 women die annually of maternal anemia and 600,000 newborn infants succumb as well. Conventional tests, such as blood cell counts, smear tests, serum iron tests and others can detect the condition before it becomes serious and guide treatment, but many poorer countries lack the facilities and trained personnel to carry them out.
HemoGlobe is an inexpensive solution to the problem that exploits that strange paradox of the developing world, the cell phone. Many areas that lack clean water or even an electric power grid are more likely to have cell phones these days. So, the John Hopkins team took the logical route of using the resources at hand.
Similar in principle to other phone-based medical devices we've looked at, the HemoGlobe consists of an inexpensive sensor hooked to a cell phone. The sensor, which is similar to the ones commonly used to measure blood oxygen levels, attaches to the patient’s fingertip. A light shines through the finger and the sensor measures the color of the blood through the skin along various wavelengths. The different colors correspond to different levels of hemoglobin in the blood.
Hemoglobin is the iron-containing protein that the body uses to transport oxygen from the lungs to the rest of the organs. It also gives blood its trademark hue. Since hemoglobin is carried by red blood corpuscles, the amount of hemoglobin translates into the number or corpuscles.
The attached phone then acts as a display for the sensor - showing a color-coded readout that indicates whether the patient is anemic and if so, how severe the condition. The clever bit is that HemoGlobe doesn’t just take readings. It automatically sends the results as a text message to a server where it generates a real-time epidemiological map of anemia cases in the area, which is a great help to health officials. The inventors estimate that the HemoGlobe conversions could be carried out for less than US$20 per phone.
The HemoGlobe was developed as part of a competition for a $250,000 seed grant in the Saving Lives at Birth: A Grand Challenge for Development competition funded in part by the U.S. Agency for International Development and the Bill & Melinda Gates Foundation. The John Hopkins team was one of twelve winners out of 500 competing teams from 60 countries. The prize money will be used to perfect the device and fund field testing next year in Kenya.
Source: The JHU Gazette