Fossil Evidence Of Borrelia (Lyme Disease Bacteria) Found

[Oxytropidoceras]

Amber discovery indicates Lyme disease is older than human

race, Oregon State University, ScienceDaily, May 29, 2014

http://www.sciencedaily.com/releases/2014/05/140529142538.htm

Lyme Disease Bacteria Found in 15-Million-Year-Old

Amber, Sci-News.com, May 30, 2014

http://www.sci-news.com/paleontology/science-lyme-disease-bacteria-amber-01956.html

Amber discovery indicates Lyme disease is older than human

race, Oregon State University, May 29, 2014

http://oregonstate.edu/ua/ncs/archives/2014/may/amber-discovery-indicates-lyme-disease-older-human-race

A couple of papers are:

Poinar, G., 2014, Spirochete-like cells in a Dominican amber

Ambylommatick (Arachnida: Ixodidae). Historical Biology.

Published online: 22 Apr 2014

http://www.tandfonline.com/doi/abs/10.1080/08912963.2014.897699

Poinar, G., 2014, Rickettsial-like cells in the Cretaceous

tick, Cornupalpatum burmanicum (Ixodida: Ixodidae).

Cretaceous Research. Available online 24 March 2014

https://www.sciencedirect.com/science/article/pii/S0195667114000147

Yours,

Paul H.

Edited June 1, 2014 by Oxytropidoceras

[FossilDAWG]

Pretty interesting, Paul. Thanks for posting this.

I work on vector-borne diseases, and want to offer a couple of points. First, Borrelia is a large genus of spirochete bacteria, with some species that are involved in human or zoonotic diseases, and many that are apparently not pathenogenic to any vertebrate host. For example Borrelia burgdorferi is the cause of Lyme Disease, but Borrelia hermsii (as just one of several examples) causes a disease called tick-borne relapsing fever. Lyme disease is vectored only by ticks in the genus Ixodes, particularly Ixodes scapularis (the black-legged or deer tick) in the northeastern/upper midwestern US and Ixodes pacificus in the west. The fossil in the paper is an Amblyomma, a genus that includes the modern lone star tick. There are Borrelia that have been isolated from the lone star tick, but they are either non-pathogenic to humans or cause a mild self-resolving infection (unless you happen to be immunocompromised). So the statement that "Lyme disease predates the human race" is one that is not supported by this fossil, as the Borrelia in the fossil are certainly not Borrelia burgdorferi. That being said, rodents (especially the white footed mouse) are the natural reservoir hosts of Borrelia burgdorferi (humans are just an incidental host and play no role in the transmission cycle in nature), so the pathogen likely does have an ancestry that predates humans, but the fossil doesn't bear on that one way or the other.

Similarly there are many species of Rickettsia, some of which are pathogenic, such as Rickettsia rickettsii which causes Rocky Mountain Spotted Fever (RMSF). There are other Rickettsia that are involved in other diseases, but there are also many species that have not been associated with any disease. RMSF is vectored by Dermacentor ticks, so again the fossils do not indicate that RMSF was an issue for Cretaceous dinosaurs or whatever those ticks fed on.

There is evidence that many of these bacteria are symbionts in their tick hosts, so the ticks themselves are helped (grow better, are more fertile) because of the bacteria in their guts. The fact that these bacteria are pathogens in us is an unfortunate side effect of the mechanism the bacteria use to move from one tick to another via the blood of the vertebrate host.

Don

Edited June 1, 2014 by FossilDAWG