(S)POC Analysis: “Highly Logical, Captain.”
When will low-cost diagnostics beam up?
Rich Whitworth |
Bioreactor breeders (parents) will know the story well: your darling returns from playgroup, but they are not alone. No. They are harboring an alien life form. An (unknown) virus (probably). The agent sweeps through your home, infecting everyone with the same grisly symptoms. Seventy-two hours later: it is gone.
Invariably, the scientist in me wonders – even amidst fever-induced delirium: “What the hell is this?” Of course, the symptoms give us some clues about the likely microorganism. We could visit a doctor for confirmation, who would probably advise in the first instance (and irrespective of the illness): “rest and plenty of fluids.” But to be fair, the doctor would also be in the dark, without easy access to a rapid (and cheap, if it’s the NHS) assay. “Dammit Spock! I’m a doctor not a diagnostician.” In this case, even if we were able to identify the culprit – norovirus, perhaps – there is no cure, only general symptom relief (rest and plenty of fluids). Not quite personalized medicine, is it? So what’s the point?
An attempt at containment, for one. Armed with details of the invader, we could consider the contagious period before symptoms (a worrying concept in itself) and after infection, and at least try to prevent further spread of... nastiness. In schools and residential care homes, early alerts to an outbreak would be most welcome. If I’m honest, I would love access to a speedy point-of-care (SPOC!) test purely to satisfy my own curiosity – but perhaps I am in the minority.
The idea is not so crazy; in 2016, researchers developed a new 3D “slip” paper-based analytical device (PAD) to detect human norovirus, following ASSURED criteria: affordable, sensitive, specific, user-friendly, rapid and robust, equipment-free, and deliverable to end-users (1).
In more severe viral infections – HIV, Zika, Ebola – rapid diagnosis, treatment and containment saves lives. Back in 2016, Waseem Asghar’s development of flexible sensors for the rapid and cost-effective diagnosis of HIV in point-of-care settings won the Humanity in Science Award, but he also turned his attention to Zika detection. Other researchers are also on the case with a rapid immunochromatography approach (2).
One thing is certain; there is a huge need for ASSURED diagnostics – and a number of research groups are dedicated to the general cause (3). But what about commercialization? Cheap or free aren’t so attractive to investors. And though ideally they should be first rolled out to those most at risk of life-threatening infectious diseases, could demand elsewhere be re-invested into further development and cost reduction?
- KN Han, J Choi, and J Kwon, “Three-dimensional paper-based slip device for one-step point-of-care testing”, Scientific Reports 6, 25710 (2016). DOI:10.1038/srep25710
- I Bosch et al., “Rapid antigen tests for dengue virus serotypes and Zika virus in patient serum,” Sci Transl Med, 9 (409), eaan1589 (2017). DOI: 10.1126/scitranslmed.aan1589
- GM Whitesides, “Using Simplicity,” The Analytical Scientist, 15, 22–28 (2014).