11. Fever and Chills
The Listeria bacteria create an immune response in the body as the brain detects the invading pathogen.
The first thing the immune system does to combat the bacteria is to turn up the body heat. This action
helps create an inhospitable environment for the bacteria, Preventing its spread and replication in the
body.
To create the fever, the hypothalamus signals for the creation of pyrogen proteins. These proteins
attach to receptors in the lower back, causing the central nervous system to increase the temperature
set point for the body. As a result, the body starts to enter a fever.
However, it may take the body some time to catch up to the new temperature set point selected by the
hypothalamus. As a result, the patient may find that they start to experience the onset of chills, even
though they have a high body temperature.
As the body catches up to the new temperature set point, they begin to notice the subsiding of the chills
and a return to fever.