Coronavirus: deadly Delta spin-offs ‘a possiblity’

As the variant continues to drive global cases, infectious disease experts are warning that more transmissible and vaccine-resistant strains could emerge where inoculation levels remain low.

Greater Sydney remains in lockdown to contain the highly contagious Covid-19 Delta variant. Picture: Lisa Maree Williams

As the Delta variant continues to drive a global surge in corona­virus cases, infectious disease experts are warning that potentially more transmissible and vaccine-resistant strains could emerge where inoculation levels are low.

While the World Health ­Organisation has identified four “variants of concern”, the Alpha, Beta, Gamma and Delta strains, experts remain concerned about four further “variants of interest” – Lambda, Eta, Kappa and Iota – which could prove even more transmissible.

The WHO has convened ­urgent discussions concerning the prospect of a new, more lethal variant arising, after leaked documents from the US Centres for Disease Control urged officials to “acknowledge the war has changed”.

The documents concluded that vaccine breakthroughs and “more community spread” could become a reality if inoculations stagnated, citing unpublished research that showed the Delta variant might be able to transmit as easily among the vaccinated population as the unvaccinated.

UNSW epidemiologist Mary-Louise McLaws said new information from the northern hemisphere suggested we are entering a potentially more dangerous phase of the pandemic as “spin-off mutations” from the Delta strain could produce a more deadly “super variant”.

A recent study by Austria’s Institute of Science and Technology suggested vaccine-resistant mutations could emerge even when populations reached 60 per cent inoculation.