Most epidemics disappear once populations achieve herd immunity and the pathogen has too few vulnerable bodies available as hosts for its self-propagation. This herd protection comes about through the combination of natural immunity in people who’ve recovered from infection and vaccination of the remaining population.
In the case of SARS-CoV-2, however, recent developments suggest that we may never achieve herd immunity. Even the U.S., which leads most other countries in vaccinations and already had large outbreaks, won’t get there. That’s the upshot of an analysis by Christopher Murray at the University of Washington and Peter Piot at the London School of Hygiene and Tropical Medicine.
The main reason is the ongoing emergence of new variants that behave almost like new viruses. A clinical vaccine trial in South Africa showed that people in the placebo group who had previously been infected with one strain had no immunity against its mutated descendant and became reinfected. There are similar reports from parts of Brazil that had massive outbreaks and subsequently suffered renewed epidemics.
That leaves only vaccination as a path toward lasting herd immunity. And admittedly, some of the shots available today are still somewhat effective against some of the new variants. But over time they will become powerless against the coming mutations.
Of course, vaccine makers are already feverishly working on making new jabs. In particular, inoculations based on the revolutionary mRNA technology I’ve previously
described can be updated faster than any vaccine in history. But the serum still needs to be made, shipped, distributed and jabbed.
https://www.bloomberg.com/opinion/articles/2021-03-24/when-will-covid-end-we-must-start-planning-for-a-permanent-pandemic?utm_source=url_link
