An extended interval between vaccination and infection enhances hybrid immunity against SARS-CoV-2 variants

[bennevisplace]

A newly published study insight.jci.org/articles/vi... takes a close look at the temporal aspects of hybrid immunity - i.e. humoral immunity after both SARS-CoV-2 infection and vaccination - in 96 health care workers.

"We find robust neutralizing antibody responses among those with hybrid immunity against all variants, including Omicron BA.2, and significantly improved neutralizing titers with longer vaccine-infection intervals up to 400 days. These results indicate that anti-SARS-CoV-2 antibody responses undergo continual maturation following primary exposure by either vaccination or infection for at least 400 days after last antigen exposure. We show that neutralizing antibody responses improved upon secondary boosting with greater potency seen after extended intervals. Our findings may also extend to booster vaccine doses, a critical consideration in future vaccine campaign strategies".

As we move from Covid pandemic to Covid endemic, with an increasing percentage of the population having been infected at least once and vaccinated several times, hybrid immunity is becoming the norm. This new study prompts a re-think of existing vaccination policy, based on earlier research into the durability of vaccine effectiveness e.g. thelancet.com/journals/lanc...

[bennevisplace]

A question many of us would like answered. Without the data we don't know - we can assume the subjects of this study all to have normal immune responses. It would be interesting to see the equivalent study in a fairly homogeneous set of immunocompromised patients. Maybe LLS has relevant data?

I doubt that such a study would debunk the existing policy of vaccinating immunocompromised folk more frequently than the majority of the population.

[AussieNeil Partner Administrator in reply to bennevisplace]

"I doubt that such a study would debunk the existing policy of vaccinating immunocompromised folk more frequently than the majority of the population."

Given the LSS and UK studies found that we could sometimes respond and make antibodies after additional jabs, I expect that it's research into the timing for booster jabs for us which is needed. Remember the recommendation by some CLL specialists for flu vaccinations twice a year?

Neil

[bennevisplace in reply to AussieNeil]

You're probably right, in that a hybrid immunity study would be less helpful for immunocompromised folk than for the rest of the population, while the booster interval would seem to be more relevant. Didn't someone recently mention this phase 3 trial? clinicaltrials.gov/ct2/show...

A vaccine designed to turbocharge the cellular immune response might help too. Again, I seem to recall there was a recent post? It all gets a bit hazy these days...