A first in Brazil: Black-faced lion tamarins vaccinated

Three black-faced lion tamarins in coastal Paraná state became the first of their species vaccinated against yellow fever in July 2026, a conservation effort to protect one of Brazil's rarest primates with fewer than 400 individuals remaining in the wild.

The vaccination program is a protective measure; its long-term effectiveness and ability to prevent disease outbreaks in the wild population remain to be demonstrated.