Listeria was first isolated from the liver of sick rabbits by Hulphers in 1911 and named Bacillus hepatitis. Later, this bacterium was called Listeria monocytogenes.
Listeria monocytogenes was the first species that came to mind in Listeria infections and the most researched species were investigated. L.monocytogenes has been described as a pathogen in humans since 1929 and a foodborne pathogen since 1981.
L.monocytogenes is a psychrotrophic bacterium that can develop in the limits of mesophyll although it is originally a mesophile character. The ability of the agent to survive and reproduce in such wide pH ranges can also develop in many foodstuffs, helping to create an infection risk.
L. monocytogenes is a very resistant microorganism to salt. 10% NaCl. The agent was reported to be able to survive 132 days in 25% NaCl. The ability of the microorganism to survive in excess saline environment also depends on pH and temperature. The ability to reproduce easily in the refrigerator temperature indicates that the development of the microorganism cannot be limited by using the cold chain in the food preservation. This poses a major problem in protecting food from Listeria risk.
The pathogen species of Listeria, especially L.monocytogenes, cause a food-borne disease called Listeriosis in humans. Listeriosis causes meningitis, miscarriage in pregnant women, lethal septicemia, endocarditis and encephalitis. Listeriosis in humans is more dangerous in pregnant women, fetus, newborn babies, elderly people and people who have weakened immune system due to various diseases. Therefore, more care should be taken to keep such people away from the disease.
The minimum infection dose of L.monocytogenes in humans is not fully known. The entry point of the infection is the digestive system and the incubation period occurs within one day following digestion.
In Listeria infections, the transmission is thought to result from primary or secondary contaminated raw or undercooked foods, and food contaminated with Listeria species after cooking for various reasons. Non-pasteurized milk, soft cheeses such as Feta, Brie and Camembert cheeses, Mexican cheeses such as Blue cheeses and queso blanco fresco, sushi, seafood such as smoked salmon, frozen shrimp, frozen, canned lobster and red meat such as ground beef, fermented sausage, deli products and poultry meat products such as chicken ground meat, meatballs and burgers pose a Listeria risk.
There are rules that consumers, especially individuals in risk groups, must comply with in order to avoid Listeria. These rules are:
Vegetables and fruits should be washed properly before eating.
Non-pasteurized milk and dairy products should not be consumed.
Foodstuffs that have obtained production permission from the Ministry of Agriculture should be consumed.
Raw eggs, raw meat of all kinds (raw meatballs, shellfish, fish, red meat) eating habits should be abandoned.
Cold prepared foods (sausage, sausage, hamburger, etc.), must be eaten after cooking
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