Scientists in Singapore develop a quicker, cheaper and potentially more reliable way to improve diagnosis in rural areas

A team of scientists in Singapore have created a new way to test for malaria within minutes using magnets. “The new technique uses a significantly smaller blood sample to traditional blood-smear methods, and is more sensitive and less error-prone,” says Donhee Ham, professor of electrical engineering at Harvard University.



Malaria currently infects over 200 million people worldwide, mainly in developing countries. This new technology could allow hospitals to rapidly screen and monitor patients for malaria at a significantly lower cost per patient, and may be portable enough to be used in the field.

So, how does it work?

Currently malaria is diagnosed by taking a blood sample from a patient, staining it with a dye, and looking at the sample with a microscope to detect the Plasmodium parasite which causes the disease.

This new technique uses magnetic resonance relaxometry (MRR) to detect a parasitic waste in the blood of infected patients. “There is real potential to make this into a field-deployable system, since you don’t need any kind of labels or dye,” says Jongyoon Han, one of the senior authors of the paper.

The researchers used a small, 0.5-tesla magnet. The current device prototype is small enough to sit on a lab bench, but the team is also working on a portable version for field-based diagnoses.

After taking a blood sample, the analysis takes less than a minute. Only a droplet of blood is needed, making the procedure much less invasive for patients and easier for healthcare workers.

Will it be expensive?

No. According to researchers the system can be built at a very low cost. “Since this technique does not rely on expensive labelling with chemical reagents, we are able to get individual diagnostic tests carried out at a cost of less than 10 cents,” says Weng Kung Peng, lead author of the paper and research scientist at the Singapore-MIT Alliance for Research and Technology.

Is it more reliable than past tests?

In the blood-smear test, the blood is stained with a dye that colours cell nuclei. As red blood cells don’t have nuclei, any marks that show up are presumed to be from the parasite. The problem is that technicians don’t always agree on the interpretation of the smears.

According to Hans, there’s a lot of variation over what counts as infected red blood cells rather than dust particles stuck on the plate: “It really takes a lot of practice.”

Because this new technique relies on magnetic fields to detect the presence of the parasitic waste, it may be more reliable as there is less scope for human error.

Is it ready to be used in the field?

Not yet. The technology is still in the early stages and will need to be tested and developed further for reliable field deployment. However, the results so far are promising. So promising in fact that researchers are launching a company to make this technology available at an affordable price.

The team has also began running field tests in south-east Asia, and is exploring ways to power the device on solar energy, making it more accessible for healthcare workers in poor, rural areas.

Read more stories like this:

Join our community of development professionals and humanitarians. Follow @GuardianGDP on Twitter.