https://www.ncbi.nlm.nih.gov/pubmed/30940200

2019 Apr 2;12(1):152. doi: 10.1186/s13071-019-3418-7.

Tick-borne pathogen detection in midgut and salivary glands of adult Ixodes ricinus.

Abstract

BACKGROUND:

The tick midgut and salivary glands represent the primary organs for pathogen acquisition and transmission, respectively. Specifically, the midgut is the first organ to have contact with pathogens during the blood meal uptake, while salivary glands along with their secretions play a crucial role in pathogen transmission to the host. Currently there is little data about pathogen composition and prevalence in Ixodes ricinus midgut and salivary glands. The present study investigated the presence of 32 pathogen species in the midgut and salivary glands of unfed I. ricinus males and females using high-throughput microfluidic real-time PCR. Such an approach is important for enriching the knowledge about pathogen distribution in distinct tick organs which should lead to a better understanding I. ricinus-borne disease epidemiology.

RESULTS:

  • Borrelia lusitaniae, Borrelia spielmanii and Borrelia garinii, were detected in both midgut and salivary glands suggesting that the migration of these pathogens between these two organs might not be triggered by the blood meal.
  • In contrast, Borrelia afzelii was detected only in the tick midgut.
  • Anaplasma phagocytophilum and Rickettsia helvetica were the most frequently detected in ticks and were found in both males and females in the midgut and salivary glands.
  • In contrast, Rickettsia felis was only detected in salivary glands.
  • Finally, Borrelia miyamotoi and Babesia venatorum were detected only in males in both midguts and salivary glands.
  • Among all collected ticks, between 10-21% of organs were co-infected.
  • The most common bacterial co-infections in male and female midgut and salivary glands were Rickettsia helvetica + Anaplasma phagocytophilum and Rickettsia helvetica + Borrelia lusitaniae, respectively.

CONCLUSIONS:

Analysing tick-borne pathogen (TBP) presence in specific tick organs enabled us to (i) highlight contrasting results with well-established transmission mechanism postulates; (ii) venture new hypotheses concerning pathogen location and migration from midgut to salivary glands; and (iii) suggest other potential associations between pathogens not previously detected at the scale of the whole tick. This work highlights the importance of considering all tick scales (i.e. whole ticks vs organs) to study TBP ecology and represents another step towards improved understanding of TBP transmission.

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**Comment**
Ixodes ricinus, commonly known as the castor bean tick, sheep tick, or deer tick, transmits numerous pathogens of medical and veterinary importance including tick-borne encephalitis virus and Borrelia burgdorferi (Lyme), and frequently bites humans. https://ecdc.europa.eu/en/disease-vectors/facts/tick-factsheets/ixodes-ricinus
The really important discovery was that three borrelia strains were found not only in the midgut but in the salivary glands – suggesting that the migration of these pathogens between these two organs might not be triggered by the blood meal.
For decades we’ve been told by the CDC that it takes a minimum of 36-48-hours for a tick to transmit Lyme to a human. Then, in 2013 we were told they needed to be embedded for 24 hours or more:  https://www.nhregister.com/columns/article/DR-KATZ-Of-Lyme-disease-and-lemonade-11412658.php
Then, microbiologist Holly Ahern came out with a fantastic video revealing that research on minimum attachment times have NEVER been done:  https://madisonarealymesupportgroup.com/2017/04/14/transmission-time-for-lymemsids-infection/

Transmission Time:  Only one study done on Mice. At 24 hours every tick had transmitted borrelia to the mice; however, animal studies have proven that transmission can occur in under 16 hours and it occurs frequently in under 24 hours.  No human studies have been done and https://www.dovepress.com/lyme-borreliosis-a-review-of-data-on-transmission-time-after-tick-atta-peer-reviewed-article-IJGM  no studies have determined the minimum time it takes for transmission.

Yet, “authorities” continue to propagate this longer window, despite Lyme/MSIDS being a true 21st century pandemic & plague.

This study finally begins pushing the ball down the hill by showing it may not take a blood meal for spirochetes already within the saliva to be much more quickly injected into humans, causing infection much more quickly.

Lastly, this is a French study. The CDC probably won’t even look at it.