Cheap Diagnostics For Tropical Diseases

Andrés Javier Bello-Hernández was born 32 years ago in a little village in the Colombian highlands. "I was fortunate to live in such a green and tranquil place, yet still enjoy the advantages of the nearby city of Bogotá, with its 8 million inhabitants," he says. As a child, he spent a lot of time outdoors, playing in the forest. At primary school, he discovered what he enjoyed and what he was good at, gravitating towards chess, music, languages and dance. He also showed an interest in science, which would ultimately shape his future. "Even as a kid, I remember wanting to know how the world worked," he says.

Bello-Hernández would go on to study chemical engineering at the Universidad Nacional de Colombia. Thanks to his strong academic performance, he gained access to intensive language courses, learning Portuguese, French, Italian and German. His proficiency in the latter was subsequently boosted during an exchange year at the Karlsruhe Institute of Technology.

Bello-Hernández enjoyed Europe's cultural diversity and international feel. After completing his Master's degree programme in Biochemical Engineering in Colombia, he returned to Europe - this time to Switzerland. When the supervisor of his Master's thesis heard that he had applied for a doctoral scholarship at ETH Zurich, he winked and said: "Well, the worst that can happen is that they say, 'Yes'!" That, of course, was exactly what happened, and in 2021 Hernández joined a research group in Zurich led by Andrew de Mello, Professor of Biochemical Engineering. The group conducts microfluidics research for applications in the fields of chemistry, biology and medicine. It was here, as part of his doctoral project, that Bello-Hernández began developing a diagnostic test for identifying dengue virus infections.

As a child, he had never come into direct contact with the disease he now studies: his home village lies at an altitude of around 2,600 metres above sea level - too high for the mosquitoes that carry this tropical disease. But dengue fever has spread significantly in recent years, including in lowland regions of Colombia, and global warming threatens to cause a surge in cases around the world. Populations in low- and middle-income countries have been hit particularly hard, because gold-standard diagnostic methods are based on PCR testing - familiar from the coronavirus pandemic - which requires expensive equipment. Affordable, portable diagnostic technologies like the ones Bello-Hernández hopes to develop could improve the situ­ation. Highly sensitive and specific rapid tests make it easier to detect dengue virus infections, thereby reducing mortality.

Dengue is a complex disease, Hernández explains: in many cases, those infected don't develop any symptoms, while others have non-specific symptoms; however, if the illness worsens, dengue can be fatal. "That's why it's so important to identify who has the disease and to place them under medical supervision. With the right treatment, you can prevent the more serious cases," he says.

A prototype of his rapid diagnostic test should be finished later this year, but Hernández is already thinking one step ahead: "This technology could also be used for other viruses and non-tropical di­seases." His dream would be to found a start-up company to bring the diagnostic test to market - perhaps even in Switzerland.