Hafniaceae

Hafniaceae is a family of Gram-negative, facultative anaerobic bacteria belonging to the order Enterobacterales. This family currently contains only one genus, Hafnia, which in turn comprises two species: Hafnia alvei and Hafnia paralvei. These bacteria are commonly found in the environment, particularly in soil, water, and sewage. They are also frequently isolated from the feces of various animals, including humans.

Hafnia alvei is the most well-known species and has been historically associated with food spoilage, particularly in dairy products and meats, where it can produce off-flavors and odors. While generally considered commensal in the human gut, H. alvei has also been implicated in opportunistic infections, especially in immunocompromised individuals or those with underlying health conditions. These infections can range from urinary tract infections and bacteremia to more severe systemic diseases.

Hafnia bacteria are characterized by their ability to ferment lactose, a key feature used in their identification in clinical and environmental microbiology laboratories. They are typically motile and produce a variety of enzymes. The taxonomy of Hafniaceae has been refined over time with the advent of molecular phylogenetic techniques, solidifying its position within the Enterobacterales. Research continues to explore the ecological roles and pathogenic potential of this bacterial family.