Listeria infection (listeriosis) – Symptoms, Causes, Complications Diagnosis, and treatments

Listeria is a food borne bacterial infection caused by eating foods contaminated by bacteria. These bacteria occur worldwide and may be very dangerous for pregnant women and people with weak immune system.  Listerosis is a rare infection and usually does not need any treatment. However, it can involve serious syndrome and even cause death in certain people. These groups of people include:

  • People with weak immune system
  • Pregnant women and also unborn babies
  • Newborn babies
  • Elder people


Listerosis symptoms may appear few days after eating contaminated food. It may take 30 or more days before the first sign of infection begins. The symptoms include:

  • Fever
  • Nausea
  • Diarrhea
  • Muscle aches

If the infection extends to nervous system then the symptoms include:

  • Headache
  • Loss of balance
  • Stiff neck
  • Changes in alertness

Symptoms during pregnancy:

The baby may die before birth or get a life-threatening infection within few days after birth. Like adults, the sign of infection in newborn can be delicate and includes:

  • Fever
  • Vomiting
  • Irritability
  • Little interest in feeding


Listeria (bacteria) can commonly develop in water, soil, and animal feces. Typically, humans are infected by consuming:

  • Contaminated animal meat
  • Unpasteurized milk
  • Foods made with unpasteurized milk
  • Raw vegetables contaminated from soil or fertilizers

Incubation period:

The average incubation period for listeria is about 30 days. After infection it can take from 1-over 90 days to develop illness called the incubation period. canton urgent care


Complications can be more severe for an unborn baby. During pregnancy, it can lead to complications like:

  • Miscarriage
  • Premature delivery
  • Infection to the newborn
  • Death of newborn

In some cases, listeria can lead to severe complications that include:

  • Septicemia (generalized blood infection)
  • Meningitis ( inflammation of membranes and fluid surrounding the brain)


Listeriosis can be diagnosed in laboratory by taking samples, which are tested for listeria germs such as samples of urine, blood, spinal fluid or amniotic fluid from the womb uterus.


Many children and adults with mild illness only require treatment of the symptoms. Medicines are used to treat fever or if you have infection of the gut then increase fluid intake. Antibiotics help to treat severe infection. People with severe symptoms should be treated in hospital. urgent care canton mi


Antibiotics help to treat listeria but prevention is better.  Some simple food safety guidelines are:

Keep things clean:

Wash your hands with soap and warm water before and after preparing or handling food. Wash utensils with warm water after cooking. Follow advice on food labels.

Scrub raw vegetables:

Clean raw vegetables with plenty of water by using a vegetable brush.

Cook food thoroughly:

Cook food such as meat, eggs, and vegetables completely by using a food thermometer.

  • Keep foods for as short period of time as possible
  • Keep cooked and raw food away from each other
  • Wash knives, hands, and cutting board after handling raw food.
  • Throw leftover reheated food.

Safe foods to avoid listeria:

In order to avoid listeria eat safe foods that include:

  • Freshly prepared food
  • Milk (freshly pasteurized)
  • Yogurt
  • Canned and pickled food
  • Freshly cooked foods

Leave a Reply

Your email address will not be published. Required fields are marked *