What Are the Symptoms of Listeriosis?

The main symptoms of listeriosis infection are characterized by aching or sore muscles and a fever. In some cases, however, stomach upset including diarrhea and nausea may also be present. In more serious incidents of infection, the symptoms of listeriosis may also include stiffness in the neck, headache, poor balance and mental confusion.

As a food-borne illness, the symptoms of listeriosis are best prevented by avoiding contact with uncooked or undercooked meat and poultry. The consumption of unwashed vegetables and unpasteurized dairy products should also be avoided. After handling these items during food preparation, hands, cooking utensils and cooking surfaces should be thoroughly washed.

Caused by a bacterium found in animals, water, soil and infected food, listeria monocytogenes poses a particular danger to individuals with fragile immune systems. People living with AIDS, HIV, cancer and diabetes must be especially careful to avoid infection, as the symptoms of listeriosis pose a more serious health threat to people with these underlying illnesses than to most other people. Other groups most at risk for infection are infants, pregnant women and aging adults. Research also indicates that individuals taking prescribed glucocorticosteroid medicines are also at increased risk of infection. While individuals who are deemed to be otherwise healthy rarely contract listeriosis, the symptoms are usually not severe or life-threatening.

In addition to the physical symptoms of listeriosis, laboratory testing can identify this infection. Specifically, blood tests and a testing of spinal fluid will alert doctors to a listeria infection. Such testing is only usually performed, however, on individuals who have had contact with contaminated foods and who are either in a high-risk group or show physical signs of infection.

For those in high risk groups, experts recommend that medical attention be sought at the earliest signs of listeriosis, particularly after eating food where an infection is suspected or after a food recall due to bacterial infection. The symptoms of listeriosis are treated with antibiotics and most people completely recover from it. In a small number of cases, however, death may result from infection.

In pregnant women, the symptoms of listeriosis are quite similar to symptoms of the influenza virus. Following this type of food poisoning, many pregnant women give birth prematurely and some infants are born infected with the bacteria. While listeriosis rarely results in death among normal populations, miscarriage after an infection is highly possible. Early antibiotic intervention, however, may prevent harm to an unborn child.