Oysters Hide Deadly Bacteria From Immune Cells

Oysters possess a defense mechanism involving immune cells known as haemocytes, which typically engulf and destroy invading microbes. However, the bacterium Vibrio vulnificus can evade this defense, leading to serious and sometimes fatal infections in humans. Studies suggest that the virulent form of V. vulnificus is less readily engulfed and degraded by oyster haemocytes compared to its nonvirulent counterpart.

Researchers hypothesize that a protective capsule surrounding the virulent bacteria may shield it from the oyster's cellular defenses. This ability to persist within oyster tissues, even after purification, highlights a significant public health concern associated with consuming raw oysters or exposure to contaminated seawater.