Listeria.

Listeria is a bacterial genus that contains six species. Named after the English pioneer of sterile surgery Joseph Lister, the genus received its current name in 1940. Listeria species are Gram-positive bacilli and are typified by L. monocytogenes, the causative agent of listeriosis.
Listeria ivanovii is a pathogen of ruminants, and can infect mice in the laboratory, although it is only rarely the cause of human disease.
Antibiotics effective against listeria species include ampicillin, vancomycin (unclear effectiveness), ciprofloxacin, linezolid, azithromycin.
Intralytix, a Baltimore, Maryland-based biotechnology firm, has created a product that combines six different bacteriophages (viruses that infect bacteria exclusively) and is applied to food and areas associated with food production. It has been shown effective in the elimination of Listeria monocytogenes bacteria.[citation needed]
EBI Food Safety has created and put a similar product on the market, LISTEX P100. LISTEX P100 reduces Listeria monocytogenes in food by using bacteriophages to kill them.
Preventing listeria as a food illness requires effective sanitation of food contact surfaces. Alcohol is an effective topical sanitizer against listeria. Quaternary ammonium can be used in conjunction with alcohol as a food contact safe sanitizer with increased duration of the sanitizing action. Refrigerated foods in the home should be kept below 4 °C (39.2 °F) to discourage bacterial growth. Preventing listeriosis also can be done by carrying out an effective sanitation of food contact surfaces.