NIE ma ustalonego czasu od ugryzienia przez kleszcza a zarażeniem się od niego Borelioza i koinfekcjami.
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TRANSMISSION TIMES
There is a delay between the time of tick attachment and pathogen transmission into the host,although this time may vary from organism to organism and tick species to tick species. This
“grace period” provides an opportunity to prevent disease transmission to people and pets via use of systemic or topical acaricides and appropriate and timely tick removal.
There are multiple factors that can affect the length of time a tick must be attached in order to effectively transmit a pathogen. These include the reactivation process of the organism, the tick species and life stage (nymph vs. adult), the environmental temperature and the type of vertebrate host. Therefore, transmission times for each pathogen can vary considerably and cannot be accurately predicted in any specific situation. However, it is generally thought that transmission times for Babesia spp. and Borrelia spp. are longer than transmission times for Ehrlichia spp. Anaplasma spp. or Rickettsia spp. Under experimental conditions I. scapularis ticks need to feed for 24 to 48 hours to ensure effective transmission of B. burgdorferi.
However, this feeding time may not be required under all circumstances and I. ricinus has been shown to transmit B. burgdorferi or B. afzelii in less than 24 hours. In addition, under experimental conditions, partially fed I. scapularis ticks transmitted B. burgdorferi in well under 24 hours when they reattached to a second vertebrate host. It is predicted that Babesia canis canis sporozoites are not transmitted by the tick until 48 hours or more after tick attachment.
Studies in dogs with Rickettsia spp., Anaplasma spp. and Ehrlichia spp. also indicate that transmission times can be less than 24 hours and Rhipicephalus sanguineous transmitted E. canis organisms to dogs within 3 hours of tick attachment. In general, however, most studies indicate that 12-18 hours of tick attachment are required to effectively transmit pathogens, and longer times are typically required for Borrelia spp.
Two additional points need to be considered. The first is that experimental work has shown that
an interrupted feeding nymph tick will seek another blood meal. Pathogen activation has already occurred during initial tick feeding and transmission time is more rapid upon reattachment to a new host. The risk of this phenomenon occurring in the natural situation is not clear. A second consideration is that manipulation of a feeding tick during human efforts to detach the tick could
increase the risk of pathogen injection.
http://cfavm.org/notes/DrAlleman/Understanding%20the%20Transmission%20of%20Tick-borne%20Pathogens.pdf.
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Lyme borreliosis is increasing rapidly in many parts of the world and is the most commonly occurring vector-borne disease in Europe and the USA. The disease is transmitted by ...ticks of the genus Ixodes. They require a blood meal at each stage of their life cycle and feed on a wide variety of wild and domestic animals as well as birds and reptiles. Transmission to humans is incidental and can occur during visits to a vector habitat, when host mammals and their associated ticks migrate into the urban environment, or when companion animals bring ticks into areas of human habitation. It is frequently stated that the risk of infection is very low if the tick is removed within 24–48 hours, with some claims that there is no risk if an attached tick is removed within 24 hours or 48 hours. A literature review has determined that in animal models, transmission can occur in <16 hours, and the minimum attachment time for transmission of infection has never been established. Mechanisms for early transmission of spirochetes have been proposed based on their presence in different organs of the tick. Studies have found systemic infection and the presence of spirochetes in the tick salivary glands prior to feeding, which could result in cases of rapid transmission. Also, there is evidence that spirochete transmission times and virulence depend upon the tick and Borrelia species. These factors support anecdotal evidence that Borrelia infection can occur in humans within a short time after tick attachment
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4278789/#b19-ijgm-8-001
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W jaki sposób kleszcz przekazuje nam te bakterie?
,,Wgryza się w naszą skórę i od razu wpuszcza do rany ślinę, w której znajdują się substancje znieczulające, więc my niczego nie czujemy. W tej ślinie znajdują się borelie. W ogóle kleszcz posiada w swoim wnętrzu całą fabrykę chemiczną. Między innymi dysponuje środkami zapobiegającymi krzepnięciu krwi, Ŝeby nie skrzepła w naczyniach krwionośnych w miejscu wkłucia. Kleszcz, karmiąc się naszą krwią, co pewien czas wstrzykuje nam swoją ślinę wraz z bakteriami ,,
http://wsseopole.pis.gov.pl/plikijednostki/wsseopole/userfiles/Zagro%C5%BCenia%20zwi%C4%85zane%20z%20kleszczami%20-%20artyku%C5%82.pdf.
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http://campother.blogspot.co.uk/2013/10/24-hours-of-attachment-is-estimate-not.html
relapsing
fever spirochetes are efficiently transmitted in saliva by
fast-feeding argasid ticks within minutes of their attachment to a
mammalian host
http://lymedisease.org/news/hardscienceonlyme/hard-science-on-lyme-ticks-can-transmit-infection-the-first-day.html
Researchers
Patmas and Remora reported on a case of Lyme disease that was
transmitted after only 6 hours of attachment by a deer tick.
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