How Bacteria Cause Illness

Bacteria can cause illness in three ways: by infection, intoxication or toxicoinfection.

A foodborne infection occurs when the microorganism itself is ingested with the food. The organism establishes itself in the host's body and multiplies. Since the infection is a consequence of growth in the body, the time from ingestion until symptoms occur is relatively long.

A foodborne intoxication occurs when specific pathogenic bacteria grow in the food and release toxins into the food that is subsequently consumed. It is the toxin that makes the person sick. Since the illness is a consequence of absorption of the preformed toxin by the intestinal tract, and not microbial growth in the host's body, symptoms of intoxication have a much more rapid onset than foodborne infection.

A third type is called toxicoinfection, which combines the two. Toxicoinfections are characterized by bacteria that are non-invasive and cause illness by producing toxins while growing in the human intestines. The times of onset are generally, but not always, longer than those for intoxications, but less than those for infections.

Examples

Examples of bacterial pathogens that have been associated with seafood products are:

Clostridium botulinium (forms spores and a toxin)

Listeria monocytogenes

Salmonella

Vibrio species

Staphylococcus aureus

- What harm can bacteria cause?

Some types of bacteria can cause diseases in humans, such as cholera, diptheria, dysentery, bubonic plague, pneumonia, tuberculosis (TB), typhoid, and many more. If the human body is exposed to bacteria that the body does not recognize as helpful, the immune system will attack them.

- How do you get rid of a bacterial infection in your body?

The treatment for bacterial infections is usually a course of antibiotics. Doctors may prescribe antiviral medications for certain viral infections, but few antiviral medications exist. There are some illnesses that tend to develop due to either bacteria or viruses.