Comment: Our urgent choice between living with or without new Covid-19 variants

While there are some concerns that the B.1.617 variants from India may be somewhat less responsive to vaccines, and perhaps more virulent among younger people, we’ve already seen that effect in previous variants of concern such as P.1 from Brazil.

For now, any shifts in these characteristics appear to be incremental rather than radical, so it’s more of a medium-term issue to keep a watchful eye on over the weeks ahead than a short-term issue demanding an immediate response within days. Based on what we know at present, the big issue with B.1.617 appears to be raw transmissibility.

While we can’t yet make any definitive estimates about just how much more transmissible B.1.617 is than B.1.1.7, the UK variant, it certainly appears to represent a major evolutionary shift up through the gears by the virus, at least on par with the P.1 variant currently devastating Latin America.

Such increased transmissibility alone makes it a cause for extreme concern and immediate, decisive action to prevent further seeding of more outbreaks here in Ireland. If we allow B.1.617 variants to establish themselves here, it may not be possible to stop them from rapidly burning their way through the remaining unvaccinated population, along with the substantial minority of vaccinated individuals who don’t mount a full immunological response.

Fortunately, there’s good reason to be optimistic that we can avoid that tragedy if we act now. Our public health teams succeeded in shrinking down P.1 because we gave them a fighting chance by introducing mandatory hotel quarantine (MHQ) for travellers originating from the major source countries in Latin America. We could have done the same with B.1.1.7 if we’d been prepared to extend that approach to the UK and then Europe.

Now we need to finally seize the nettle of comprehensive MHQ to keep the so-called Indian variants, which are currently growing out of control in the UK, at bay. We will also need to start working on trailer exchange and border bubble systems like those used to tackle interstate transmission in Australia, and that’s no small task so we need to get started immediately.

Right now, we need to buy enough time to fix those remaining holes in our national canoe and there may not be a way back if we hesitate. Let’s not wait to see what happens in the UK – doing so would risk putting ourselves in exactly the same situation. I’ve been through pandemics that no-one could stop and I’d hate to see that now happen in Ireland because we were too indecisive or too neighbourly. We still have an opportunity to prevent that from happening and the first step is immediate extension of MHQ to all countries with ongoing transmission, which means everywhere for now.

If we do the right thing now, we leave ourselves with manageable options we can chose from going forward. We can carefully develop and tentatively road-test a robust exit strategy from MHQ over the medium term, as coverage of existing vaccines becomes comprehensive and second-generation vaccines against multiple antigens address authentic concerns about vaccine-resistant variants evolving in the future.

However, we’ll never have a time machine allowing us to undo harsh lessons learned through irreversible mistakes and crystal-clear hindsight. This may be the most stark and difficult decision we’ve faced since the start of the pandemic but also the most important.

Gerry Killeen is the chair of Applied Pathogen Ecology, School of Biological, Earth and Environmental Sciences and the Environmental Research Institute, University College Cork