http://lymedisease.org/news/hardscienceonlyme/905.html
HARD SCIENCE ON LYME: Research Finds Bartonella Transmission from Tick to Host
26th January 2012
Click above to share articles
It
has long been known that ticks harbor Bartonella and that humans who
have Lyme disease may also have Bartonellosis. However, the actual
transmission of Bartonella from tick to host has not been demonstrated
until a mouse study by Drs Reis and colleagues was published in May
2011. The study is available free on line for those interested. “This
work represents the first in vivo demonstration of a Bartonella sp.
transmission by ticks. It . . . corroborate[s] a prospect that ticks
play a role in the natural cycles of some of the bartonellae including
those pathogenic for humans. Consequently, bartonelloses should be
included in the differential diagnosis for patients exposed to tick
bites.”
The study also found that transstadial transmission is high. This means that bartonella
survive in the tick through the molt from one life stage to another,
for example from nymphal ticks to adult ticks. It had been thought that
the possible mechanism of transmission of bartonella might be
through contaminated tick feces. LymeDisease.org funded a study at UC
Davis pursuing this theory. However, this study confirms that
transmission to the host occurs with saliva and not through contaminated
feces.Bartonella have also been detected by either PCR, serology, or culture in humans and animals after tick bites without any known contact with other arthropods. This study is very important to patients with Lyme disease because it confirms that the transmission of bartonella from ticks may produce Bartonelleosis. Note that this contradicts the guidelines of the Infectious Diseases Society of America on Lyme disease, which provide: “Bartonella DNA has been found in some Ixodes species, but there is no convincing evidence that Bartonella infections can be transmitted to humans by a tick bite.” This points to another example of how the IDSA Lyme guidelines–which were written in 2006 before this study was published–are now outdated.
The study by Drs. Reis and colleagues is entitled, “Vector Competence of the Tick Ixodes ricinus for Transmission of Bartonella birtlesii” (PLoS Negl Trop Dis. 2011 May; 5(5): e1186) is available free online at http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3104967/?tool=pubmed.
