STEALTH VIRUS

THE SARS-CoV-2 STEALTH VIRUS

There’s something very sinister about a potentially fatal virus that doesn’t declare its presence with a decent set of symptoms until a week or more after contact. The thought that this virus might be lurking undetected while a serious infection is brewing gets in the way of practical conversations about when we need to do about it.

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Now that we’re beginning to understand the immediate consequences of having no effective treatment or vaccine, people are starting to ask what we should do until that elusive vaccine puts a stop to this pandemic personification of SARS-CoV-2. It really doesn’t help that this virus can transform your close friends and family into a clear and present danger to your own health.

Submerged munitions. This coronavirus has adapted it genetic code to exploit every opportunity to improve its chances of spread among the human population before detection, just like mines submerged out of sight beneath the waves. No question of icebergs here; the virus is completely undetectable when it matters most. Straying into a minefield is not something you choose to do, but that is exactly what we risk doing if we blunder back to pre-pandemic normal without more permanent measures to inactivate the viruses we detect. It doesn’t seem that smart to wait for a second wave of cases, or even a steady trickle of sporadic cases before we act, as that looks like a step back to the reactive phase of the pandemic.

Sweeping the coronavirus minefield. The line the World Health Organisation took early in the pandemic emphasised the importance of high throughput testing to generate the data disease control specialists use to target their countermeasures. Wherever SARS-CoV-2 tests have been actively deployed, including adaptive testing of asymptomatic people, there have been disease control benefits. Admitted, physical distancing, barrier controls and disinfection are currently the sum total of our effective coronavirus countermeasures, but there is a limit to how long coronaviruses can last in a hostile inanimate environment without another unsuspecting victim. Clearance from human populations after the end of local transmission requires patience. In the absence of the minesweeping effect of antiviral treatment, we’re going to need a large measure of forbearance.

How long will this last? Spoiler alert: we’re going to be at this physical distancing and enhanced hygiene deal well beyond the next few months. Patience is a quality admired in others, but one we’ll  hurry past in a dash to the finish. In a recent disease forecasting study, the most likely COVID-19 scenarios were explored on the assumption that effective antiviral therapy or vaccines won’t be widely available in the near future. While some nations have either dodged the worst of it, or put a brake on the initial wave of pandemic infection, a flatter curve is not the same as COVID-19 elimination. We’ll be hearing ‘Are we nearly there?’ from the back of the car for some time yet.

Making the journey a bit less dangerous. It’s becoming crystal clear that there’s no direct, through route to the post-COVID-19 uplands. For some, the worst dangers are past, but the way to an effective vaccine is unlikely be plain sailing. We’re going to learn a lot about this virus, how to live with it, and what needs adapting from the pre-pandemic normal. A previous analysis came up with an adversary profile that emphasised this unseen passenger that exploits the weakness of human behaviour and health administration. It follows that on the route out of the pandemic we will develop a finely tuned awareness of this disease, strongly founded on diagnostic test results, and guidance from disease control. It has been heartening to see what can be achieved when public health and their laboratory services co-ordinate their work. This is not a minesweeper competition to detonate as many mines as possible no matter what the collateral damage. Mine clearance needs a light touch, determination and patience.

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