Research suggests fish brains contain living microbes, raising questions about human brain microbiome

Recent research suggests that fish brains contain living microbes, challenging the belief that vertebrate brains are sterile due to the blood-brain barrier. Scientists found bacteria in both the olfactory bulb and other brain regions of trout and salmon. The study, led by Irene Salinas at the University of New Mexico, took five years to confirm the presence of these microbes. The team used various methods to ensure the bacteria were indeed residing in the brain tissue and not from contamination. Salinas proposes that these microbes may have entered the fish brains during early development, before the blood-brain barrier fully formed. This discovery raises questions about the potential existence of a human brain microbiome.