Pathogens are disease causing agents, such as bacteria, viruses, or other microorganisms. Although bacteria are very commonly found in the human body, doing no harm, and even benefiting human health, in some cases bacteria can become pathogenic, being detrimental to the proper functioning of the body.

Phelix is interested in the effect particular pathogenic bacteria have on those who have a chronic infection.
We aim to explore the link between chronic infection and neurodegeneration.

Here are some of the pathogenic bacteria we study:


Borrelia is a genus of bacteria of the spirochete phylum. It causes Borreliosis, a disease transmitted primarily by ticks and lice, depending on the species. It is an obligate parasite which, when in the body, can live inside the cells and cause damage.
The bacterium are named after the French biologist Amédée Borrel. There are currently 36 known species of Borrelia.


Rickettsia is a genus of bacteria. They are also obligate intracellular parasites.
Rickettsia are transmitted by ticks, fleas and lice and are associated with human disease such as typhus.




Mycoplasma is a genus of intracellular bacteria which lack a cell wall around their cell membrane which makes them difficult to treat with antibiotics.
Some species have been linked with pneumonia and inflammatory conditions.




Chlamydia is a genus of obligate intracellular bacteria. The bacteria are known to cause ocular, genital and respiratory infections.
There are 3 species of Chlamydia and all three can cause disease in humans.





More about the link between chronic infections and neurodegenerative conditions.