Ranu S. Dhillon Devabhaktuni Srikrishna David Beier
Amid current outbreaks of Ebola in the Democratic Republic of Congo (DRC) and Nipah virus in India, an even scarier threat looms. Last year, researchers recreated an extinct smallpox-like virus with DNA bought online for just $100,000 and published how they did it. Their feat heightens concerns that rogue regimes and terrorists could similarly modify or engineer pathogens and use them as weapons. Former U.S. Secretary of Defense Ash Carter warned that such biological artillery might come to rival the destructive power of nuclear arms. If a highly contagious agent were released in a major city, it could spread far and wide and kill thousands before it is even clear what is happening. Responding effectively to such threats will require a paradigm shift towards approaches that are faster and more agile and decentralized than what exists now.
The low cost and do-it-yourself accessibility of genomic technologies makes it possible for such weapons to be deployed by almost any aggressor. Even small changes are enough to produce dangerous effects: A single mutation was all it took to transform Zika from a relatively routine infection to one that could cause brain damage in newborns. The fact that there would be no way of knowing who launched such an attack also potentially lowers the threshold for their use. Perpetrators could even design and release several deadly pathogens at the same time, hampering our ability to respond and sowing confusion.
After an engineered agent is released, we would likely have a window of only several weeks to prevent it from causing a global catastrophe. This requires controlling transmission so that each infected person infects, on average, less than one additional person, causing the epidemic to stall and begin to contract. Our recent track record against naturally occurring epidemics, however, is troubling and doing more of what we already do better will not be enough to stop agents designed to spread and kill faster.
Current response efforts rely on developing vaccines and therapeutics and health systems that centralize capacity for diagnosis, isolation, and treatment in fixed-point hospitals. Vaccines and therapeutics, however, take years to develop and some pathogens, such as HIV and malaria, evolve ways to elude immunity or harbor resistance that make them difficult to target even when time and resources are not limitations. In an era of synthetic biology, bioweapons encoded with such evasive features could potentially be created faster than vaccines and therapeutics to counter them. Innovations, such as synthetic vaccine platforms and monoclonal antibodies, could enable faster deployment, but even in the best case would still take months — too long for contagions that double within weeks and are difficult to bring under control once already widespread.
Without vaccines and therapeutics, we use contact tracing to track down and isolate infected persons to prevent them from exposing others and provide them with supportive care, such as intravenous fluids, to boost their chance of survival. But that capacity is concentrated in hospitals, which, even in high-income countries, can quickly be overwhelmed and also potentially promote transmission among people crowding into them. The United States has only about 5,500 hospitals with a combined total of approximately 900,000 beds, enough for less than 0.3% of the population at any given time. A fast-spreading contagion could fill these beds within days with infected patients as well as others who fear they may have been exposed. We need look no further than this year’s flu season when even the United States and the United Kingdom faced shortages of hospital beds, health workers and essentials like IV fluids. Similarly, laboratory testing capacity was overrun during the Zika crisis when, even in Florida, many pregnant women could not get tested. In bio-attacks, contagious patients flooding into health facilities or commercial laboratories for testing would overwhelm this capacity and expose others rushing to these same places in the process.
These gaps cannot be remedied simply by building more hospitals and laboratories that languish unused until there is an emergency. More agile and decentralized approaches underpinned by new technologies are needed that bring diagnostic and treatment functions closer to where people live with less need for specialized personnel and infrastructure that cannot be scaled.
This type of approach would enable patients to be diagnosed in the home, school, office, or community and be isolated before they infect others. Several current and emerging technology platforms (e.g.. CRISPR, nanotechnology, nanopores, immunoassays) could improve the ability to do this. These platforms aim to detect any pathogen, including engineered microbes, with accuracy from small samples of blood and urine that do not require skilled technicians to collect or process. Such diagnostics could be evolved to the point they can run off smartphones or laptops, enabling patients to screen themselves and, like smoke detectors, continuously monitor the environment for threats.
In addition to diagnostics, more efficient ways to surge isolation and treatment capacity are also needed. Rapidly deployable tent hospitals like those used in war zones could be quickly established and, when transmission is widely spread, people could also be isolated in their homes. Self-testing approaches could be coupled with telemedicine consultations using Skype- or FaceTime-like technologies to assess patients and Amazon-like services to home-deliver medications and treatments. Mobile medical teams could be dispatched to visit patients in need of more hands-on care in their homes while precious hospital beds and the risk of transporting contagious patients could be reserved for those truly in need of intensive care.
These approaches or strategies like them and the tools necessary for their implementation should be developed and prepared. Just as advances in technology have brought us to the precipice of a merger between two of humanity’s greatest threats — disease and war — new thinking and innovations can help us be prepared to respond effectively if those threats become a reality.
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