Durable

 One of the questions about the COVID-19 vaccines is whether they will provide durable immunity six months or more after the last vaccine. Indeed, some folks are already getting boosters.

So far, the news appears to be good on the durability of vaccine protection:

"Wherry’s group found that memory B cells generated by the mRNA vaccines made by Moderna Inc. and Pfizer Inc. and its partner BioNTech SE appeared better at blocking virus variants including alpha, beta and delta, than those produced in response to a mild case of Covid-19.

Additionally, high levels of vaccine-induced T cells, a type of white blood cell capable of finding and killing virus-infected cells, were detected after six months, “maintaining an additional armor to protect us,” Wherry said.

The findings help to explain why immunization remains effective at protecting against severe Covid-19, hospitalization and death even as more break-through infections occur.

“We’re seeing a drop in efficacy when you only measure whether people get infected, but really, really steady immunity if you’re measuring severe-disease outcomes,” Wherry said. “That fits with the idea that circulating antibodies are going to protect you from infection, but memory B cells and memory T cells, while they may not eliminate the ability to have some virus in your nose, they’re actually going to prevent severe disease.”

The immune backups will also decrease the duration of Covid symptoms, prevent them from worsening, and reduce the likelihood of transmitting a SARS-CoV-2 infection to other people, he said.

“Vaccinated people are really not fueling this fire; it’s really unvaccinated people that are,” Wherry said. https://www.bostonglobe.com/2021/08/28/nation/antibodies-waning-immune-system-has-backup-plan-that/?p1=HP_Feed_ContentQuery