The Delta surge in England has remained muted, even as restrictions have been lifted and schools have returned. In Florida and other Southern U.S. states it has been more severe, but it is now clear that it peaked in mid to late August and is now in many places in steep decline. Florida, Mississippi and Georgia are famous for having lifted restrictions either last autumn or in the spring and not imposing new ones in response to the arrival of Delta. In Florida the Governor actively opposed the imposition of mask mandates by school districts. Yet new daily reported infections in the Sunshine State have been in steep decline for weeks – see the positivity graph above. Declining daily reported infections for the three southern states are shown below.
These states show what an unmitigated surge of the Delta variant can look like. They demonstrate, once again, that the epidemic peaks and declines naturally with no need for interventions.
The big question now is, is Delta the last variant, does it represent a kind of evolutionary endpoint for SARS-CoV-2, or will another variant capable of partial immune evasion and thus causing a surge emerge in the coming months?
The worldwide graph of reported infections (below) clearly shows the three variant-based waves since autumn 2020 – B.1.177 (20A.EU1, the ‘Spanish’ variant) in autumn 2020, Alpha in spring 2021 and Delta in the summer.
New reported infections are currently declining worldwide as the Delta variant exhausts itself and herd immunity is re-established. There is no sign yet of a new surge anywhere linked to a new variant that might come to replace it, as there was with Alpha in the U.K. last autumn and with Delta in India in the spring. It remains to be seen whether SARS-CoV-2 has exhausted its options for evading the immune system or whether it has more tricks up its sleeves.