A rapid test using a mobile phone will be able to identify the most severe cases of imported malaria within minutes

Malaria remains the mostly deadly parasitic disease in the world. Although it is not endemic to countries such as Spain, imported cases are diagnosed each year in people returning from areas where the infection is common. These patients can rapidly progress to severe forms of the disease, but detecting which patients are at higher risk is not always easy, especially in settings where clinical experience is limited and initial symptoms are non-specific.

A recent study led by a research team from the Universitat Rovira i Virgili (URV) and ISGlobal (Barcelona Institute for Global Health), a centre promoted by the “la Caixa” Foundation, has led to the development of a new tool to tackle this challenge. Basically, it is a system that uses a mobile phone to combine rapid diagnostic tests with video analysis and it is capable not only of detecting the infection in under six minutes but also of predicting which patients may develop severe forms of malaria.

The study, published in the journal Biosensors and Bioelectronics, focuses on the analysis of two biomarkers produced by the malaria parasite: the PfHRP2 protein, specific to Plasmodium falciparum, the parasite that typically causes the most severe form of the disease, and the enzyme pan-lactate dehydrogenase (pan-pLDH), present in Plasmodium spp. Using laboratory immunoassays and lateral flow tests—similar to those used during the pandemic—the researchers compared the ability of both markers to both diagnose malaria and identify the most severe cases.

They found that, while PfHRP2 is highly accurate for confirming infection, the pan-pLDH biomarker is particularly useful for identifying patients at risk of severe disease, even when used in simple rapid tests. “This finding is crucial, as it provides relevant information for decision-making without the need for complex laboratory equipment,” explains Claudio Parolo, a Ramón y Cajal researcher in the Department of Chemical Engineering at URV and an external associate researcher at ISGlobal.

This advance has so far been validated in non-endemic settings, where malaria is uncommon but potentially very severe, and where access to specialised diagnostic tools is often limited to referral centres. However, the researchers believe the strategy could be transferable to places where the disease is endemic in the future, because it provides low-cost rapid tests using the widely available technology of the mobile phone. Its performance does, however, need to be validated in these settings, taking into account epidemiological and clinical differences.

The research was led by Dr Claudio Parolo, a researcher at ISGlobal, together with Daniel Camprubí, a doctor at the International Health Service of the Hospital Clínic de Barcelona. The work formed part of the doctoral thesis of ISGlobal predoctoral researcher Julia Pedreira and also received support from the data science team coordinated by Paula Petrone of the Barcelona Supercomputing Center, which contributed to the quantitative analysis of the results.

Currently, the team is continuing to work on validating the results in larger samples and in real clinical settings, with the aim that, in the near future, a simple rapid test using a mobile phone will become a standard tool for the early identification and assessment of imported malaria.