This can include potentially harmful pathogens such as listeria, toxoplasmosis, and salmonella. Listeriosis is an infection caused by the bacterium "Listeria monocytogenes". The fungus inhibits growth of the bacteria "Listeria monocytogenes". "Listeria monocytogenes" is a gram-positive bacterium. STING deficient monocytes are intrinsically defective in migration to the liver during "Listeria monocytogenes" infection. Most "Listeria monocytogenes" strains are pathogenic to some degree. In this way, STING protects host from "Listeria monocytogenes" infection by regulating monocyte migration. Meropenem is bactericidal except against "Listeria monocytogenes", where it is bacteriostatic. A bacteriophage, "Listeria phage P100", has been proposed as food additive to control "L. monocytogenes". The major human pathogen in the genus "Listeria" is "L. monocytogenes". "Listeria monocytogenes" is ubiquitous in the environment. Representative genera include "Bacillus", "Listeria" and "Staphylococcus". Pasteurization and sufficient cooking kill "Listeria"; however, contamination may occur after cooking and before packaging. The non-spore formers are "Corynebacterium" and "Listeria" (a coccobacillus), whereas "Bacillus" and "Clostridium" produce spores. Listeria ivanovii is a species of bacteria in the genus "Listeria".