The shingles vaccine is shown to be 97% effective at preventing shingles in adults between the ages of 50 and 69 with healthy immune systems, and 91% effective in adults aged 70 years and older, reports the CDC. It adds that in adults with weakened immune systems, the shingles vaccine is 68% to 91% effective at preventing shingles. In regards to preventing long-term nerve damage from shingles, the Shingrix vaccine is 91% effective in adults aged 50 years and older, and 89% effective in adults aged 70 years and older, according to the CDC.