Phylum Proteobacteria, Class Gammaproteobacteria, Order Enterobacteriales, Family Enterobacteriaceae, Genus Hafnia,
- Hafnia alvei, Moller 1954. In the past, Hafnia was considered a member of the genus Enterobacter and named Enterobacter hafniae,
Obesumbacterium proteus biogroup 1 may be a synonym of Hafnia alvei hybridization group 1.
- Hafnia paralvei Huys et al. 2010, previously Hafnia alvei hybridization group 2.
Gram-negative, straight, 1.0 x 2.0-5.0 μm, bipolar appearance bacilli. No capsule
produced. Motile by peritrichous flagella at 22-30 ºC, sometimes nonmotile strains.
Colonies are smooth (S type), low convex, entire edge, gray, 2 mm diameter after 24h
Facultatively anaerobic, optimum growth temperature 22-37 ºC. Grow on Nutrient agar
or nutrient broth, Trypticase Soy Agar ± 5% sheep blood, Mac Conkey, SS agar,
Drigalski, EMB agar.
Widely distributed in nature. Isolated from soil, water, dairy products and rarely from clinical specimens (feces) from humans & animals.
Hafnia alvei is an opportunistic pathogen. May cause nosocomial infections associated with other germs (septicaemia, enteritis,
urinary tract infections, pneumonia, absceses). H. alvei has been associated with cases of diarrhoea (some strains of H. alvei-like
are now known as Escherichia albertii ).
On animals may cause abortus, pneumonia, peritonitis or mammites. Has been associated with haemorrhagic septicemia of trout in
Bulgaria. May affect bees (bacteremia), especially those parasited with Varooa jacobsoni.
Wort contaminant (brewery).
- J. G. Holt et al., 1994. Facultatively Anaerobic Gram-Negative Rods. Subgroup 1. Family Enterobacteriaceae. In: Begey’s Manual of
Determinative Bacteriology, 9th-edition, Williams & Wilkins, pp 175-189.
- Don J. Brenner and J.J. Farmer III, 2001. Family I. Enterobacteriaceae. In: Bergey’s Manual of Systematic Bacteriology, Second
edition, Vol two, part B, George M. Garrity (Editor-in-Chief), pp 587-897.
- MJ Albert, K Alam, M Islam, J Montanaro, A S Rahaman, K Haider, M A Hossain, A K Kibriya, and S Tzipori Hafnia alvei, a probable
cause of diarrhea in humans. Infect Immun. 1991 April; 59(4): 1507–1513.
- Kevin B Laupland, Deirdre L Church, Terry Ross and Johann DD Pitout: Population-based laboratory surveillance of Hafnia alvei
isolates in a large Canadian health region. Annals of Clinical Microbiology and Antimicrobials 2006, 5:12
- Moller V. : Distribution of amino acid decarboxylases in Enterobacteriaceae. Acta Pathologica et Bacteriologica Scandinavica,
1954, 35, 259-277.
- Geert Huys, Margo Cnockaert, Sharon L. Abbott, J. Michael Janda, and Peter Vandamme. Hafnia paralvei sp. nov., formerly known
as Hafnia alvei hybridization group 2. Int J Syst Evol Microbiol August 2010 60:1725-1728.
Positive results for catalase, ONPG test, arginine dihydrolase, nitrate reduction, growth
on KCN media, Voges-Proskauer reaction (positive at 25 ºC and variable at 35 ºC),
acid production from: glucose, D-mannitol, rhamnose, L-arabinose, glycerol, maltose, D-mannose, trehalose and xylose.
Negative results for oxidase, lysine decarboxylase, ornithine decarboxylase, indole production, esculin hydrolysis, H2S production,
citrate utilization, malonate utilization, acetate utilization, DN-ase, lipase, urease, phenilalanine deaminase, gelatinase, acid
production from: D-adonitol, D-arabitol, erythritol, lactose, myo-inositol, D-sorbitol, sucrose, melibiose, D-arabinose, cellobiose,
dulcitol, alpha-methyl-D-glucoside, raffinose, salicin and mucate.
Hafnia paralvei can be separated from H. alvei by negative beta-glucosidase test, acid production from D-arabinose and no acid
production from: malonate and salicin.
(c) Costin Stoica