What is the vaccine efficacy and safety status for the live varicella vaccine and recombinant zoster vaccine?

The rationale behind the high efficacy rate of both the live varicella vaccine and the recombinant zoster vaccine stems from extensive clinical trials that demonstrate their ability to significantly reduce the incidence of the diseases they are designed to prevent. The live varicella vaccine is known to provide over 90% effectiveness against chickenpox, particularly after the second dose is administered. Similarly, the recombinant zoster vaccine has shown to be over 90% effective in preventing shingles among older adults.

The safety profile for these vaccines generally indicates a favorable outcome, with most individuals experiencing only mild to moderate side effects. This combination of high efficacy and reasonable safety makes the statement regarding both vaccines' effectiveness clearly valid.