Cytomegalovirus infects 60–90% of adults by age 70 and silently consumes up to 30% of the body's T-cell reserve. Epstein-Barr virus has now been linked to multiple sclerosis. Both are targets of an emerging mRNA vaccine pipeline that could extend the logic of the shingles vaccine to the next frontier of longevity medicine.
The shingles vaccine's association with slower biological aging introduced a paradigm that longevity medicine has been slow to fully absorb: latent viruses are not passive passengers. They reactivate, generate chronic immune activation, and accelerate aging through a mechanism called inflammaging. Varicella-zoster virus (VZV) is the one for which we now have population-level biological aging data and a highly effective vaccine.
But VZV is not the only herpesvirus hiding in your body. Two others — cytomegalovirus (CMV) and Epstein-Barr virus (EBV) — are arguably more consequential for immune aging and are now at the center of one of the most promising developments in longevity-adjacent medicine: mRNA vaccine programs targeting latent viral burden.
This article covers what CMV and EBV do to the aging immune system, why their effects go well beyond the infections they cause, and what the current vaccine pipeline looks like for both.
To understand why CMV and EBV matter for aging, you need the basic biology of herpesvirus latency.
Herpesviruses — a family that includes VZV (shingles), CMV, EBV, herpes simplex viruses (HSV-1 and HSV-2), and several others — share one defining characteristic: after primary infection, they are never fully cleared. The immune system suppresses replication, but the virus retreats into specific cell populations and establishes a permanent latent state.