Scientists recognize more than a dozen tick borne diseases and new ones are still being discovered. One tick may carry more than one disease, so sometimes people get more than one co-infection from the bite of a single tick.
Co-infections are opportunistic infections caused by pathogens, particularly opportunistic pathogens (those that take advantage of certain situations), such as bacterial, viral, fungal or protozoan infections that usually do not cause disease in a healthy host. A compromised immune system, however, presents an "opportunity" for the pathogen to infect the host rendering them very ill. Normally where there is Lyme, there are co-infections which makes treatment that more difficult.
New organisms are being discovered in ticks all the time, such as toxoplasmosis, giardia, roundworms, tapeworms, thread worms,amoebas, clostridia, the herpes virus family, parvovirus B 19, leptospirosis,chronic strep infections, molds and fungi, active measles (in the small intestine), Chlamydophila pneumoniae, Human Herpes Virus #6 (HHV6). Some of these infections may have been already present prior to being infected with Lyme. Each add to the complication of Lyme disease. Since few MD's are not literate in Lyme or other zoonotic infections they will fail to recognize symptoms as a specific co-infection, as well as Lyme itself.
Co-infections are not all the same in each person. Some Lyme infected people may not have any coinfections at all and then others may have many.
These are the most common co-infections - for a COMPLETE list of co-infections, click here.