We know that minimum times for borreliose is about 24-36hrs. Is this also the case for tularemia and TBRF?
yes, indeed, a good citation about transmission of borrelia. But what about the other creatures? Are there investigations into that?
Sibylle,
While I do not know the answer to your question, I would speculate that ticks need not be attached to a host to transmit F. tularensis for as long as they do to transmit B. burgdorferi, because F. tularensis can be transmitted by mechanical damage alone from mosquito and blackfly bites:
http://www.ncbi.nlm.nih.gov/pubmed/18842136
Other questions to consider in thinking about how long a tick must be attached to a mammal before it can transmit a particular pathogen are:
Can this pathogen be transovarially transmitted in the tick? If so, there's a potentially higher pathogen load in the tick by the time it attaches to a human. For Ixodes ticks and B. burgdorferi, the answer to this question is no; for Amblyomma and Dermacentor ticks and F. tularensis, it's an open question, as the article referenced above notes.
and
Does this pathogen have to change its gene expression to be able to successfully be transmitted from an arthropod to a mammal? If so, the tick probably has to be attached for longer for transmission to occur. For B. burgdorferi, the answer is yes: outer surface protein A (OspA) allows tick gut colonization, OspC allows transmission to a mammal; OspC is only expressed at higher temperatures; thus it takes a while for OspC to be expressed. For F. tularensis, the answer is, um, maybe? There are certainly a lot of genes in F. tularensis that are differentially regulated at mammalian and tick temperatures, but the relevance of these genes to transmission and to survival in mammals is unclear:
http://www.ncbi.nlm.nih.gov/pubmed/18842136
Sorry this isn't more definitive, but I hope it is helpful.
Best,
Rachel
There is no minimum attachment time for ticks infected with viruses of tick-borne encephalitis or Powassan. It was shown that human infection takes place during the first 15 minutes after tick attachment (see references in my paper Uspensky and Ioffe-Uspensky, 2006, which you'll find through ResearchGate). Best regards.
okay, thank you, good answer. But what about Babesiosis, Rickettsia and Ehrliochiosis. Minimum attachment times needed?
I can advise two more publications:
P.Katavolos et al. 1998. J. Infect. Diseases, 177: 1422-1425;
E.Hodzic et al. 1998. J. Clin. Microbiol., 36: 3574-3578.
Besides, there is a great difference in the duration of tick attachment necessary for infection with Bor. burgdorferi betwwen different Ixodes ticks. If for I. scapularis it is about 48 hrs, for I. persulcatus it is less than 24 hrs.
All the best.
Thanks, do you have any recent research results /profound explanations into why the attachment time of I scapularis is usually longer than for I.ricinus for transmission to occur?
The proportion of unfed Ixodes persulcatus with borreliae in the salivary glands is much greater than that of I. scapularis. See Korenberg and Moskvitina, Journal of Vector Ecology, 1996, 21 (2): 178-185. I don't specially follow this area of research, but my impression is that this topic has been studied rather insufficiently.
Best regards.
Well, yes thank you, I persulcatus is not the one that we can be overly interested in (as you might imagine due to its distribtion). But it is certainly an interesting topic that will attract more interest in future, I fathom.
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