Insider InterviewThe importance of testing in the face of pandemicsPaul Davis, GADx illuminates the potential of antigen tests in fighting against future pandemics, and the importance of ensuring equal access to testingPharmafocus: How might antigen tests, developed to combat COVID-19, help tackle future pandemics? Paul Davis: Pandemics are caused by new pathogens (or mutated versions of established pathogens) which, unexpectedly, are able to infect human beings and can easily pass from person to person. It may be that a pathogenic virus, for example, acquires a new capability (perhaps by random mutation) to establish infections in the upper respiratory tract of humans. That capability immediately opens the door to rapid spread on a global scale, as we saw in the COVID-19 pandemic. Such a virus exploits not just the cosy, welcoming environment of the human respiratory tract, but also the normal social behaviour and interactions of human beings. We gather in crowds, we face people when we talk or sing; activities which launch aerosols and larger fluid droplets into the air, ready to be breathed in by other people. In addition to this, we cough and sneeze in response to the virus infection – a behaviour in which ‘my pathogens become your pathogens’.Once the ability to infect and pass from person to person has been acquired, a pandemic is on the cards. However, there are actions we can take to limit and control the spread to try to prevent this.Antigen tests play a key role in disease management. Simple, accurate, rapid tests must be made available, so that individuals know when they are harbouring virus loads that can infect others, and can therefore change their behaviour and social interactions, to the extent that they don’t pass on their infections. Behavioural changes like self-isolation, scrupulous mask-wearing, and avoiding open coughing and sneezing in public spaces can be effective in limiting spread, and can consequently reduce the likelihood of a fullblown pandemic. A positive test, properly promoted internationally, should be a powerful incentive for anyone to keep their pathogens to themselves for the limited time in which they are contagious.How crucial have rapid diagnostic tests been in controlling the spread of COVID-19? Properly managed, plentiful supplies of user-friendly, accurate antigen tests, have been very important components of the overall response to COVID-19. In the early days, blanket lockdown was all we had, and that helped contain the spread, but it was not enough. Self-isolation when infection is properly diagnosed is more effective and much more acceptable.Rapid tests have been crucial in this case, as individuals must be able to diagnose themselves easily and quickly in order to selfisolate before interacting with others. Here at GADx (formerly Mologic), daily testing of everyone proved to be highly effective, with very few infections passing on in the workplace.However, it’s difficult to determine exactly which factors have brought us to the point at which COVID-19 is in decline in many nations.What other factors are pivotal in ensuring pandemic preparedness? Rapid rollout of vaccinations on a global scale is one of the most important factors to ensure preparedness. However, it takes time to develop vaccines, and so it’s not preventative, it’s reactive. To help speed this process up, procedures, scientific networks, and preplanned coalitions for vaccine development should be put in place, as well as planned processes for manufacture, regulatory approval, and distribution.The same goes for diagnostic tests. The particular challenge is to develop the tests extremely quickly so that they can be deployed before the pandemic has got out of control – much quicker than was possible with COVID-19. The availability of reagents can be a limiting factor in the speed of development, and so we need high-performing antibodies to be made far quicker than has ever been possible before.Plentiful supplies of high-quality PPE, and low-cost but efficient face masks, are also important factors, and help to ensure both virus-release and pick-up are inhibited. The challenge is to encourage the use of PPE, as populations don’t normally adopt maskwearing to anywhere near the required extent to stop a pandemic.In his new book, ‘How to Prevent the Next Pandemic’, Bill Gates makes a particularly important point: It’s normal, essential practice to prepare for earthquakes, plane crashes, and other sorts of natural or man-made disasters by having exercises that enable key players to work through realistic scenarios and properly prepare for when the real thing happens. Nobody has been making any plans for such preparatory exercises in pandemic preparedness.As LFTs are no longer free of charge, what impact is this having on public health? Again, this is very difficult to discern. It seems appropriate at this time in the UK to start relaxing a bit more, with a high proportion of vaccinations, fewer hospital admissions for COVID-19 complications, and only very rare deaths. Tests should be available to those who need them (because of availability), and they should be available at low cost, whether to the state or individuals.What is important is that continued surveillance studies are being carried on for the foreseeable future based on antigen tests. The data from these studies are used to inform government strategy, as well as to keep the public informed about the prevalence of COVID-19.How can we ensure equitable access to antigen tests around the world? This is a major part of our mission, vision, and purpose. Our company has been transformed into a social enterprise, so that we can address this important challenge as our highest priority. It will need us to advance the science and technology for developing high-quality but lowcost diagnostic tests, working with partners and suppliers in other companies, institutions, and academia.To ensure that our products are made available and used properly, we will need to engage with international agencies for procurement and distribution, organisations that can provide funding and governments that can open doors, as well as provide policies and operational support.There are huge challenges ahead, and we can’t undertake our journey alone.Paul Davis is Co-Founder and CSO of GADx. Paul has worked in immunology for 45 years and has founded or co-founded eight bioscience businesses since 2002, with Mologic being the most prominent. As GADx's Chief Scientific Officer, Paul leads the Centre for Advanced Rapid Diagnostics (CARD), funded by the Bill & Melinda Gates Foundation. Until 2002 he was as a senior scientist at Unilever Research, leading applied immunology, and is one of the inventors of the lateral flow immunoassay.