Its all relative.

Measles is 3x more infectious than even Delta.

Current vaccines are 95% effective against the original strain, 60% vs Delta, unknown vs Omicron.

You boost the vaccine however, and you're back to 90% efficacy vs Delta, and like 75% vs Omicron.

The difference isn't as minor as I think you're suggesting. Compared to 95% efficacy, 90% efficacy means twice as many vaccinated people get sick and 75% efficacy means five times as many get sick. I don't see how eradication programs would work with such a differential, and (relatedly) I don't know of any experts who think it's feasible to eradicate Covid with current technology.

> I don't see how eradication programs would work with such a differential

Its all about R0. If the efficacy (and compliance) is above the 1 / R0 rate, then eradication is possible.

As its "efficacy times compliance", the number we wish to maximize is the smaller number. Efficacy may have dropped to 60% (double shot vs Delta), but a 3rd booster brings the efficacy back up to 90%.

Compliance however, is stuck around 60% in the USA in general, and a large number of people are refusing to get the booster. As such, compliance is the number we need to work on right now.

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Going from 90% to 99% vaccine efficacy barely does anything, because our vaccine compliance numbers are so damn low.