How AI is Joining the Fight Against Malaria and Sickle Cell Disease
Malaria is a life-threatening disease caused by Plasmodium parasites spread through the bite of a particular genus of mosquito. Despite being easily treatable and preventable with modern medicine, it is the world’s second most widespread infectious disease behind hepatitis B, and is particularly prevalent in developing tropical regions where access to healthcare is limited. The World Health Organisation estimates that almost half the world’s population is at risk of malaria, and as a result, a target of a billion diagnostic tests every year has been set to curb its spread. Unfortunately, these tests can be time-consuming and expensive in vulnerable regions, and it is clear that this is a problem which must first be solved in the fight against malaria.
Despite sharing little similarities with the disease itself, malaria has an unusual link to another dangerous disease with which healthcare providers face the same problems. Sickle cell disease refers to a group of inheritable genetic disorders which alter the shape of haemoglobin proteins found in red blood cells, ultimately distorting these cells into a curved sickle shape which die quickly and can build up in blood vessels. This can result in anaemia, clots, and strokes, as the oxygen supply is cut off from tissues around the body, and is therefore a potentially lethal disease responsible for the deaths of around 500 children every day. However, like malaria, it is difficult to test for in deprived regions; in Ghana, for example, only 4% of babies are tested at birth. Sickle cell disease appears to share very few characteristics with malaria, but they are both linked through one particular substance found in the blood.
The distribution of the sickle cell gene and severe malaria cases throughout Africa (Credit: University of Florida)
From the image above, it can be seen that there is a distinct overlap in cases of malaria and the sickle cell gene. In fact, the sickle cell gene is more commonly found across the world in regions where malaria cases are more abundant. This is due to a substance called haem found free in the blood. Haem is a component of haemoglobin, the protein used to transport oxygen, and when it carries the sickle cell gene, the haem oxygenase-1 enzyme is stimulated to break it down, releasing carbon monoxide gas. Higher levels of carbon monoxide in the blood protect against malaria developing even when the sufferer is infected with the parasite, which means that carrying the gene for sickle cell disease, even if you don’t actually suffer from it, reduces your chances of getting malaria. For this reason, populations living in regions vulnerable to malaria have evolved a higher proportion of sickle cell genes than they would have elsewhere, and while this does provide protection against one disease, the chances of developing sickle cell disease are much higher. This was highly considered during the creating of Hemex Health’s Gazelle® diagnostic platform.
The Gazelle® device - fast, portable, and about the size of a toaster (Credit: Hemex Health)
Just in time for World Sickle Cell Day on the 19th of June, Hemex Health released its new product made in collaboration with Case Western Reserve University. Named the Gazelle®, the device is capable of two different tests - one for malaria, and one for sickle cell disease. The aim of the device is to provide affordable and easily-accessible diagnostics to low-resource and at-risk communities, thereby allowing quick detection and treatment before it’s too late. It has already been approved for use in situations such as border screenings and epidemics by India and Ghana, both of which are vulnerable to the two diseases.
Gazelle® is ‘the smartphone of diagnostics’ because it integrates powerful consumer electronics, digital storage and wireless communication into a portable, multi-disease platform. Our mission is focused on using these powerful, affordable technologies to improve diagnostics for those living in low resource settings.
The first test is for malaria, and works by detecting trace concentrations of the biocrystal hemozoin, which is synthesised by all Plasmodium parasites during haemoglobin digestion. This test is relatively simple and fast, only taking up to one minute, and allows over 2500 individual results to be stored locally or transmitted to the Cloud for epidemiological tracking.
The second test for sickle cell disease is more complex, and can take up to eight minutes. Using a process called cellulose acetate electrophoresis, the device uses a field of electrical charge to separate charged haemoglobin molecules from a fluid suspension. Then, by analysing incorrectly-formed haemoglobin variants signifying sickle cell disease, the device is able to determine whether or not the patient is a sufferer. The test requires minimal training to use, and it is hoped that these earlier diagnoses could prevent tens of thousands of child deaths every year.
Today, Hemex Health is continuing to work on distribution of their Gazelle® devices, and has recently contributed to developing similar tests for COVID-19 for use under the same difficult conditions.
(Thumbnail Source: Malaria No More)