mRNA vaccine shows protective promise for young Asian elephants against lethal virus
Researchers from Baylor College of Medicine and the Houston Zoo have demonstrated that an experimental mRNA vaccine can trigger lasting immunity and prevent disease in juvenile Asian elephants infected with EEHV.
A 15-year partnership between Baylor College of Medicine and the Houston Zoo has yielded an mRNA vaccine that appears effective against elephant endotheliotropic herpesvirus (EEHV), a leading cause of death in young Asian elephants. The initial study examined nine elephants at five institutions and recorded a durable immune response to multiple viral antigens. A follow-up trial at the Cincinnati Zoo reported that two vaccinated juveniles, previously lacking maternal antibodies, mounted strong defenses and recovered from a low-level infection without clinical signs.
Researchers explain that the vaccine is intended to replenish waning immunity rather than block infection entirely. Houston Zoo officials now report greater confidence in herd health, and plans are underway to vaccinate 22 elephants across nine U.S. facilities by year-end, with export discussions ongoing for India, Thailand, Australia, Canada and the U.K.
Why it matters
The vaccine could dramatically lower fatal EEHV cases, safeguarding endangered Asian elephants in captivity and potentially in the wild.
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