3 ms·
> The plague bacteria of 550 AD was probably not completely identical to the one in 1350 AD either. Both plagues were caused by the same bacteria, Yersinia pes
by Maursault 4y ago
> The plague bacteria of 550 AD was probably not completely identical to the one in 1350 AD either.
Both plagues were caused by the same bacteria, Yersinia pestis. I don't see how being "completely identical" would matter, only that it was the same species of bacteria.
- inglor_cz 4y agoYes, it matters. Different strains of the same species of bacteria can have different virulence in human (or animal) hosts.
- Maursault 4y agoDifferent strains of the same bacteria species can produce different immune responses, but if the species is pathogenic to humans, all its strains will also be considered the same pathogen. The Plague of Justinian and the Black Death were both known to be virulent in that they were both rapid, severe, and destructive, but virulence is not an objectively measurable quality.