officials tout the vaccine's efficacy against the delta variant but have this warning. >> if in the future some additional mutations pile on here so that the virus is really turning out to be quite different than where we started last year in the wuhan outbreak, then we could face a moment where the vaccines are no longer as effective and that would be a world of hurt. >> white house press secretary jen psaki says we're not going back to lock downs. >> this as the white house announces the 4th of july milestone, 70% of adults have received at least one shot with just over 60% fully vaccinated. we're averaging more than 63,000 cases a day.