Hashgraphs for healthcare

10 November 2021



Developing Covid-19 vaccines was a huge challenge, but successfully distributing them is another. Long-touted as revolutionary for pharma, distributed ledger technology has the potential to greatly improve supply chains. Mae Losasso speaks to Tom Screen, technical director at Everyware UK, to find out how this technology has been implemented by the NHS to monitor the storage and supply of the vaccine – and why it might be key to the future of healthcare.


Hear the word blockchain and you’ll struggle to conjure a mental image. Instead, at this very moment, some associative terms are likely bubbling to the surface of your mind: bitcoin, probably; cryptocurrency, perhaps; overheated digital hype, almost certainly. For at least the past five years, the term blockchain has crept quietly into our lives, and as each chain gets longer, the uses, impacts and applications of the technology expand, increase and evolve. But what really is it? And what has it got to do with pharmaceuticals?

“So much of it gets muddled up with bitcoin,” says Tom Screen, technical director at Everyware UK. “That’s one of my biggest issues with the public perception of it – that it’s all about cryptocurrency and actually, by a vast mile, that really misses the point. Fundamentally, distributed ledger technology solves a decades-old computer science problem; and that is: how do you get computers to agree on the state of something?”

The term distributed ledger technology (DLT), is key – and it’s the conflation of this with blockchain that has helped to muddy public perception. Put simply, the distinction is like the difference between a vacuum cleaner and a Hoover: blockchain is only one model of DLT among thousands of models.

What, then, is DLT? Jargon and acronyms aside, it’s precisely what it says it is: a virtual ledger, or database, on which data is distributed across a series of separate nodes. We’ve had ledgers and databases for years, so what makes the distributed model so significant? In short, the distributed ledger not only democratises both storage of and access to data, it also promises that the data on a chain is immutable, guaranteeing (at least in theory) the authenticity of any given data set.

“It’s all about having a trust-led public database where you can read and write information,” Screen explains. “So, if you’ve got two different companies and they’ve both got a record-keeping system, how do those two companies agree on the order in which things happen in that system, [and on the] state of the data in that system?” Or, for that matter, how can those two companies trust one another at a more personal level, to ensure that tampering doesn’t take place? As Screen notes, that element of distrust is where human emotion gets in the way of sharing information without the data security provided by a DLT.

NHS turns to tech

This is just one argument among many for the use of DLTs. Another significant application lies in ensuring safety in a healthcare context – which is precisely what Screen, and his company Everyware, has been developing over the past 12 months. An internet of things (IoT) solutions provider, Everyware has been working with the NHS for several years to aid in the storage and supply of drugs. For example, the company adds sensors to hospital fridges to consistently monitor the temperature of the contents – be that a flu vaccine, eyedrops or chemotherapy drugs – and to ensure that pharmaceuticals remain within the required range of 2–8°C. All the data these sensors collect is then stored on Everyware’s cloud-based platform, releasing nurses from the menial – not to mention error-prone – task of jotting down a fridge temperature twice a day.

In 2020, however, the stakes were raised as the contents of hospital fridges across the country became a site of special interest: millions of bottles of the Covid-19 vaccine were being stored in the refrigerators that Everyware were monitoring. Enter Hedera Hashgraph, makers of a DLT platform that Everyware and South Warwickshire NHS Foundation Trust worked with to help store and track the data that these sensors were collecting. So, while Everyware’s technology was monitoring the vaccine around the clock, Hedera’s ledger could “prove that data is accurate, that we’ve never changed it, we’ve never tampered with it [and] we’ve never lost any,” as Screen explains.

Screen, who had been sceptical about the practical application of blockchain in the past, was an instant convert when he discovered Hedera. “When I first came across Hedera it was a no-brainer,” he says. “[I thought] this is the answer, this is the way forward. In my mind there is no competition.”

Hedera has patented a DLT model called a hashgraph, which, as Screen argues, is mathematically, ethically and environmentally superior to the blockchain model. While blockchain requires a leading node – which is both vulnerable to hacking and hugely energy inefficient – hashgraph works exponentially, meaning that every node plays its part in achieving a 100% efficiency rate. “It creates this continuous chain, almost as if you were knitting a scarf,” Screen explains. “And that’s why it’s called a hashgraph. It’s a graph of hashes.” For all the digital mystification, the semantics around these technologies are surprisingly literal.

What’s more, as Screen says, Hedera has a “100-year vision to be the de-facto standard, which enterprises […] will build on top of.” He claims that they’re “technically the best, the cheapest and the fastest”, alongside having the lowest energy consumption, which is always important environmentally.

On top of these advantages, Screen describes Hedera’s governance model as “world class”. He says it has “created a governing council of the biggest companies around the world, [which] will be the custodians of this network, each of them for a short period of time. And they themselves are distributed geographically and across different industries, [which] rules out any potential conflicts of interest.”

The need for transparency

A no-brainer, then, as Screen says. Yet, for a technology that brands itself explicitly in terms of transparency, trust, openness and communication, it’s surprisingly difficult to pin down its key figures, both at Hedera and beyond. While requests to speak the CEO of Hedera were bounced on to partner companies, blockchain strategists at other global enterprises agreed to interviews, only to pull out at the last minute due to a ‘conflict’ (whether of interest or time is unclear). Even when you do get someone on the phone, descriptions of the technology tend to remain abstracted, couched as analogies and what-ifs, rather than practical, on-the- ground case studies, because NDAs and privacy policies keep the facts sealed away – on ledgers that are supposed to be transparent.

Of course, when it comes to healthcare, there’s a big question about how transparent we really want our information to be – so it’s reassuring to know that the companies who the government outsources its databases to aren’t quick to dish the data. As Screen reveals, there’s also an implicit question mark over who in the hospital setting is even afforded access to that data. “It’s all managed on the system,” he explains, “so ward staff have access to the data, pharmacists have access to the data, but it’s very strictly controlled […] there are all kinds of security policies and privacy policies around that, which I would hope goes without saying.”

This raises another question about the use of DLTs in a medical context: the issue of immutability. As every exponent of blockchain will tell you, the greatest virtue of this technology is its immutability. Yet, as a recent IBM Institute for Business Value paper notes, the “issue of how immutability squares with regulatory rules requiring the easy deletion of consumer data is [an] area of interest” – and one that doesn’t align with the EU General Data Protection Regulation (GDPR), which grants consumers the right to have their data deleted. As the IBM paper explains, “development of viable responses to these challenges are underway, including not placing highly sensitive data, such as medical records, directly on the blockchain. Instead, the information is saved in a database and only stored as a hash on the blockchain”.

Revolution on the way?

All of this is simply a reminder that DLTs are in their infancy, working out the teething problems that come with the development of any new technology. But it’s also a reminder that the technical revolution promised by the disciples of DLT comes with an attendant set of risks and fears. Do we want our data to be immutable? Do we trust the silent companies in which DLT, by its very nature, necessitates that we place trust? And what about jobs? Do these ledgers present just another instance of automation, of replacing human labour with machine power? “Yes,” Screen admits, “that may well be [the case]. But on a multigenerational timescale, it really doesn’t matter if you’re made redundant in the grand scheme of things, because it’s about that bigger trajectory. And having more information available means that you can do more things. It’s not about replacing you, it’s about giving you more information to be able to make better decisions.”

Although invoking the multigenerational timescale in the face of possible redundancy might seem like an echo of ‘let them eat cake’, in fact, Screen comes back, again and again, to the very real potential of DLT to “empower the people further down the chain.” Often, he says, “these people […] don’t necessarily feel as though they’re in a position to raise a hand and say, ‘excuse me, I think there’s something wrong here’, because they don’t want to disrupt the process, [and] because the manager will usually say ‘you’re creating a problem for me’. This is very much an endemic cultural issue. So having some automated processes in there, is empowering because […] it becomes objective.”

If Screen is right, there’s more to DLTs than blockchain, bitcoin and the buzz of cryptocurrency. His techno-utopian vision feels genuinely revolutionary – both within healthcare and beyond, both on a longer time scale and for right now, both for society and for the individual. But we can only hope that those who hold the keys feel the same. For a technology that’s rooted in trust to work, we need be sure that the people at the top are worth trusting. Transparency, by definition, must cut both ways – because nobody wants their data immutably etched onto one-way glass.



Privacy Policy
We have updated our privacy policy. In the latest update it explains what cookies are and how we use them on our site. To learn more about cookies and their benefits, please view our privacy policy. Please be aware that parts of this site will not function correctly if you disable cookies. By continuing to use this site, you consent to our use of cookies in accordance with our privacy policy unless you have disabled them.