KUINKA NOPEASTI BAKTEERI SIIRTYY PUNKISTA IHMISEEN?

Asiantuntijana Soile Juvonen TTT

Valvojat: Bb, Sailairina, maranoma, Tiina

KUINKA NOPEASTI BAKTEERI SIIRTYY PUNKISTA IHMISEEN?

ViestiKirjoittaja soijuv » Ma Touko 30, 2011 11:24

KUINKA NOPEASTI BAKTEERI SIIRTYY PUNKISTA IHMISEEN?

Soile Juvonen TTT

Joidenkin tutkimusten mukaan borrelia-bakteeri saattaa siirtyä punkista ihmiseen melko nopeastikin.

Leuba Garcian ym (Sveitsi 1994) tutkimuksessa borrelia-bakteereita oli punkin suoliston lisäksi sylkirauhasissa joten tartunta voi tapahtua jo veriaterian alussa eikä vasta tuntien kuluttua. Aiemmin on esitetty arvioita että bakteereita on punkin sylkirauhasissa vain noin 5%:ssa punkeista. Tässä tutkimuksessa niitä oli 36%:ssa.

M. Krounin esittämässä potilastapauksessa, punkki oli kiinnittyneenä lapseen noin 4 tuntia. Lapselle kehittyi tyypillinen ihomuutos. Vasta-ainetesti, ELISA, oli positiivinen. Lapsi sai 14 vrk:n suonensisäisen antibioottihoidon, mutta hoito ei auttanut. Lapselle kehittyi myöhemmin neurologisia oireita. Selkäydinnesteen vasta-ainetesti oli normaali.

Patmasin ja Remorcan tutkimuksessa bakteeri siirtyi punkista ihmiseen 6 tunnissa.
Angelovin tutkimuksessa esitetään tapaus, jossa bakteeri siirtyi alle 24 tunnissa ja tapaus, jossa henkilö sai bakteeritartunnan saatuaan punkin vatsan sisältöä silmiinsä. Moskvitinan ym. tutkimuksessa borrelia bakteereita löydettiin usein punkkien sylkirauhasista. Saksalaisessa Maiwaldin ym. tutkimuksessa tutkittiin 730 punkinpureman saanutta henkilöä. 11,3 % punkeista oli PCR positiivisia, 60 henkilöstä 16 sairastui Borrelioosiin. Tutkijoiden mukaan sairastumisriski on suurempi kuin on aiemmin oletettu.

Yleisissä ohjeissa kerrotaan usein ns. oikea tapa poistaa punkki iholta. Tämän pitäisi vähentää tartunnan riskiä. Kahlin ym. tutkimuksen mukaan sillä miten punkki poistettiin, ei ollut minkäänlaista merkitystä bakteerin tarttumisriskiin. Tutkimuksessa gerbiileiltä poistettiin punkki eri menetelmin: a) pinseteillä ilman esikäsittelyä, b) punkki vedettiin ulos vasta sen jälkeen kun sitä oli ensin puristettu voimakkaasti 3 minuutin ajan, c) punkin päälle levitettiin kynsilakanpoistoainetta noin tunti ennen sen poistoa. Puolet gerbiileistä oli saanut borreliatartunnan 16,7 ? 28,9 tunnin sisällä riippumatta siitä miten punkki oli poistettu.



TUTKIMUKSIA

Characterization of Borrelia burgdorferi isolated from different organs of Ixodes ricinus ticks collected in nature.

Leuba Garcia S, Kramer MD, Wallich R, Gern L. Int J Med Microbiol Virol Parasitol Infect Dis 1994 Mar; 280(4): 468-75
http://www.ncbi.nlm.nih.gov/entrez/quer ... t=Abstract

Borrelia burgdorferi was isolated from 22 out of 133 adult Ixodes ricinus ticks collected from vegetation at two sites in Switzerland. From 17 ticks, spirochetes could be isolated from more than one organ. When the different isolates obtained from one tick were compared by SDS-PAGE analysis, differences in the protein profiles were observed in 8 cases. The isolates were further compared by immunological methods using mono- and polyclonal antibodies. Differences were observed in the proteins of 31-35 kDa and 18-25 kDa. Genetic divergence among isolates was evaluated by use of a B. burgdorferi specific gene probe for ospA. Correlation could be observed between immunological differences in OspA defined by monoclonal antibody LA31 and genetic variation of ospA as judged by restriction fragment length polymorphism (RFLP).

Our findings indicate that systemic infection in unfed I. ricinus adults, as reflected by isolation of B. burgdorferi from multiple organs of one tick, is more frequent (8/22, 36%) than previously described (5%). Moreover, the presence of different B. burgdorferi phenotypes/genotypes in one tick is described for the first time.

The findings may have bearings (i) on the time of tick attachment required for spirochete transmission since borreliae are already present in the salivary glands of systemically infected ticks at the beginning of the blood meal and (ii) perhaps also on the diversity of B. burgdorferi phenotypes inoculated by these ticks.v
The presence of Borrelia in the intestines and salivary glands of spontaneously infected adult Ixodes persulcatus Schulze ticks during bloodsucking


Transmission of Bb after short duration tickbite (<24h):

(unpublished case story reported by Marie Kroun at a staffmeeting in Kolding, Denmark, March 1996)
I had a pediatric case, a girl who had done tick check about 4 hours after a walk in the forest. A tick was found behind the ear and removed properly (in the ER). She developed a typical EM-rash at the site of the bite and became seropositive for Bb on ELISA and later she developed neurological problems (nystagmus, convulsions), but spinal fluid was normal (not positive spinal-index on two occasions) and she had no relief from 14 days IV antibiotics, so it was not proven that her neurologic problems were due to borreliosis, but it raised the concern that it might be related. We can't do culture or PCR for borrelia here in Denmark, except for scientific purposes. The only test available is the ELISA for anti-flagellin!

Disseminated Lyme disease after short-duration tick bite
Patmas MA, Remorca C. Journal of Spirochetal and Tickborne Diseases 1994; 1:77-78

Lyme disease, an Ixodes tick-borne spirochetal infection, has been the subject of much controversy. One problematic area has been the prophylactic treatment of deer-tick bites in endemic areas. Some have argued against routine antimicrobial prophylaxis based upon the belief that transmission of Borrelia burgdorferi is unlikely before 24-48 hours of tick attachment. Others have suggested that it is cost effective to administer prophylactic antibiotics against Lyme disease when embedded deer-tick bites occur in endemic areas. Herein, a case of disseminated Lyme disease after only 6 hours of tick attachment is presented. The current recommendation against treatment of short-duration tick bites may need reconsideration, particularly in hyperendemic areas.

Unusual features in the epidemiology of Lyme borreliosis.
Angelov L. Eur J Epidemiol 1996 Feb; 12(1): 9-11 http://www.ncbi.nlm.nih.gov/entrez/quer ... t=Abstract
In this study two cases of Lyme borreliosis are presented. First, the author describes how he contracted Lyme borreliosis 24 hours after he visited an endemic area. The second case described is that of a woman who developed Lyme borreliosis symptoms, when intestinal content of an infected tick came into contact with her conjunctiva. In both cases the diagnosis is based on clinical picture and positive serological tests. The first case shows the probability of contracting Lyme borreliosis when the duration of the tick's attachment to the skin is less than 24 hours. The second case, described demonstrates transmission of B. burgdorferi by contact.

Transmission rate of Bb from bites of infected ticks:

Previous studies have shown that even in case the tick was infected with Borrelia burgdorferi the rate of transmission was usually low (<= 5%), but this work implicate that the rate of transmission from infected ticks may be much higher?

Transmission risk of Borrelia burgdorferi sensu lato from Ixodes ricinus ticks to humans in southwest Germany.
Maiwald M, Oehme R, March O, Petney TN, Kimmig P, Naser K, Zappe HA, Hassler D, von Knebel Doeberitz M. Epidemiol Infect 1998 Aug;121(1):103-8
htt://www.ncbi.nlm.nih.gov/entrez/query ... t=Abstract
The risk of Borrelia burgdorferi infection and the value of antibiotic prophylaxis after tick bite are controversial. In this study, performed in two areas of southwestern Germany, ticks were collected from 730 patients and examined by the polymerase chain reaction (PCR) for B. burgdorferi. To assess whether transmission of B. burgdorferi occurred, the patients were clinically and serologically examined after tick removal and during follow-up examinations. Data from all tick bites gave a total transmission rate of 2.6% (19 patients). Eighty-four ticks (11.3%) were PCR positive. Transmission occurred to 16 (26.7%) of 60 patients who were initially seronegative and could be followed up after the bite of an infected tick. These results indicate that the transmission rate from infected ticks in Europe is higher than previously assumed. Examination of ticks and antibiotic prophylaxis in the case of positivity appears to be indicated.

Risk of infection with Borrelia burgdorferi sensu lato for a host in relation to the duration of nymphal Ixodes ricinus feeding and the method of tick removal.
Kahl O, Janetzki Mittmann C, Gray JS, Jonas R, Stein J, de Boer R. Zentralbl Bakteriol 1998 Jan; 287(1-2): 41-52
http://www.ncbi.nlm.nih.gov/entrez/quer ... t=Abstract
The objectives of the present study were to investigate the risk of B. burgdorferi s.1. (Bb)-transmission by I. ricinus-nymphs to a host (i) after different periods of feeding, and (ii) with regard to the particular method of tick removal. On each of 72 Mongolian gerbils 3 tick nymphs taken from a highly infected batch were allowed to feed in a small capsule. Feeding ticks were removed 16.7, 28.9, 47.0, and 65.2 hrs post-attachment. In each of these 4 groups 3 sub-groups with 6 gerbils each were deticked by (a) pulling ticks out with forceps without any pretreatment, (b) pulling ticks out after 3 min of intensive squeezing, and (c) applying nail polish to ticks 1.1 hrs before removal. The infection status in each gerbil was subsequently determined by larval xenodiagnosis. All gerbils with ticks removed > or = 47 hrs post-attachment were found to be infected. After 16.7 hrs as well as after 28.9 hrs of tick feeding, approximately 50% of the gerbils had acquired a transmissible infection, thus Bb-transmission to a host may even occur in the early phases of I. ricinus feeding. There is no evidence from this study that the tick removal method used has any significant influence on a host's Bb-infection risk.

Preliminary studies on virus and spirochete accumulation in the cement plug of ixodid ticks.
Alekseev AN, Burenkova LA, Vasilieva IS, Dubinina HV, Chunikhin SP. Exp Appl Acarol 1996 Dec; 20(12): 713-23
http://www.ncbi.nlm.nih.gov/entrez/quer ... t=Abstract
We provide evidence that tick-borne encephalitis virus and Borrelia burgdorferi s.l. are accumulated in the cement plug in the host skin within the first few hours after tick attachment. Extirpation of the tick without the cement plug, even very soon after the attachment, did not prevent the transmission by Ixodes ricinus, Ixodes persulcatus or Dermacentor reticulatus to mice. This was within 1 hour in the case of the TBE virus and after 20-22 h of attachment, in the case of Borrelia and I. persulcatus. The epidemiological significance of these findings is discussed.

Borrelia burgdorferi sensu lato in female cement plug of Ixodes persulcatus ticks (Acari, Ixodidae).
Alekseev AN, Arumova EA, Vasilieva IS. Exp Appl Acarol 1995 Sep; 19(9): 519-22
http://www.ncbi.nlm.nih.gov/entrez/quer ... t=Abstract
Borrelia burgdorferi sensu lato was detected in one out of five cement plugs of female Ixodes persulcatus ticks. The spirochetes were found by dark field microscopy as early as 18 h after attachment of the ticks to the skin of a white mouse. The relevance of this finding is discussed in relation to the epidemiology of Lyme borreliosis.

Accelerated transmission of Lyme disease spirochetes by partially fed vector ticks.
Shih CM, Spielman A. J Clin Microbiol 1993 Nov; 31(11): 2878-81
http://www.ncbi.nlm.nih.gov/entrez/quer ... t=Abstract
To determine how rapidly Lyme disease spirochetes (Borrelia burgdorferi) can be transmitted by partially fed vector ticks (Ixodes dammini), attached nymphs were removed from their hosts at various intervals post-attachment and subsequently permitted to re-feed to repletion on noninfected mice. We confirm previous reports that ticks deposit Lyme disease spirochetes in the skin of their hosts mainly after 2 days of attachment. Those that have been removed from a host within this interval can reattach and commence feeding. Spirochete-infected nymphs that have previously been attached to a host for 1 day become infectious to other hosts within another day. Noninfected nymphs acquire infection from spirochete-infected hosts within a day of attachment and become infectious to other hosts 3 to 5 days later. Virtually all ticks transmitted infection when reattaching after first feeding for 2 days. We conclude that partially fed nymphal ticks transmit spirochetal infection more rapidly than do ticks that have never been attached to a host and that infected ticks become infectious before they molt.


Moskvitina GG, Korenberg EI, Gorban' Lia. Med Parazitol Mosk 1995 Jul-Sep(3): 16-20
http://www.ncbi.nlm.nih.gov/entrez/quer ... t=Abstract
A direct microscopic analysis of fixed smears and live preparations was used to reveal whether spirochetes are present in the gut and salivary glands of adult Ixodes persulcatus ticks spontaneously infected with Borrelia garinii and B. afzelii. Unfed ticks collected from a vegetation, partially fed ticks removed from human bodies, and ticks deliberately fed on laboratory animals were studied. In each preparation, all spirochetes were counted in 250 microscopic fields, and their concentration per 100 microscopic fields was determined. A total of 1962 ticks were individually analysed. The methods used on the study allowed a reliable identification of Borrelia in the viscera of not only unfed, but also of partially fed ticks. The infection rate in ticks that started bloodsucking was slightly lower than in the unfed ticks. This was associated with the decreased spirochete concentration in the preparations made from the partially fed ticks. Borrelia were frequently found in the salivary glands of the unfed infected I. persulcatus. During the first two to three days of bloodsucking, neither the proportion of ticks with spirochetes in the salivary glands, nor the spirochete concentrations increase. Borrelia migration from the tick gut into the salivary glands during early bloodsucking is not a prerequisite for or even important for pathogen transmission with saliva. The transmission rate appears to depend on the baseline proportion of the unfed ticks carrying spirochetes in their salivary glands

The frequency of generalized infection in adult fasting ticks of the genus Ixodes in foci of borreliosis in Russia and the USA
Moskvitina GG, Korenberg EI, Spielman A, Shchegoleva TV.
Parazitologiia 1995 Sep-Oct; 29(5): 353-60
http://www.ncbi.nlm.nih.gov/entrez/quer ... t=Abstract
A total of 740 adult Ixodes persulcatus ticks were collected from the vegetation by flagging in Russian foci where Borrelia afzelii and B. garinii circulate, and 156 I. dammini ticks were collected in northwestern USA regions in foci with B. burgdorferi s.str. circulation. Smears prepared from the internal organs of ticks were stained according to Romanovsky-Giemsa and analyzed under a microscope at a x 1125 magnification. All borreliae in 250 microscopic fields were counted, and concentration of microbial bodies per 100 microscopic fields was determined. The general level of infection by Borrelia in both vectors was similar: 26.2 x 3.2 in I. persulcatus and 26.3 +/- 7 in I. dammini. However, the proportions of ticks with generalized infections differ considerably (12.9 +/- 4.8 in I. persulcatus compared with 2.4 +/- 4.8 in I. dammini; significance of difference t = 3.1). We did not reveal any definite increase in the proportion of ticks with borreliae in the salivary glands among ticks with high concentrations of microbial bodies in the gut. In 25 I. persulcatus ticks with generalized infections, series of actual numbers of borreliae (per 100 microscopic fields) found in the gut and salivary glands did not correlate with one another (r = -0.23). These results confirm our previous conclusion (Korenberg, 1994) that frequencies of generalized infection in main vectors of different ixodid tick-borne borrelioses are also different, which is probably due to peculiarities of relationships between spirochetes of each species and corresponding tick vectors. These factors can be responsible for differences in the ways of horizontal and vertical transmission of pathogens belonging to the group under study.

http://lymerick.ulmarweb.dk/Transmissio ... e-time.htm
Viimeksi muokannut soijuv päivämäärä Ke Touko 30, 2012 09:45, muokattu yhteensä 1 kerran
soijuv
 
Viestit: 3097
Liittynyt: Ke Tammi 21, 2009 14:16

ViestiKirjoittaja soijuv » To Syys 08, 2011 10:27

http://www.terveysportti.fi/xmedia/duo/duo94555.pdf

Borrelia burgdorferin DNA:ta erythema migrans -potilaiden ihossa, veressä ja virtsassa.

Italialaisessa tutkimuksessa selvitettiin geenimonistustekniikalla Borrelia burgdorferin DNA: n esiintymistä iho-, veri - ja virtsanäytteissä.
Kaikilla 30 potilaalla DNA:ta löytyi ainakin yhdestä näytteestä. Seitsemällä potilaalla sitä löytyi kaikista, 16 potilaalla iho- ja verinäytteestä, kahdella ihosta ja virtsasta ja viidellä vain ihosta.

Tulos viittaa siihen, että Lymen borrelioosissa, joka on monen elimen sairaus, taudinaiheuttaja voi levitä jo varhain paikallisen ihoinfektiokohdan ulkopuolelle. (Acta Derm Venereol 2004;84:106)
soijuv
 
Viestit: 3097
Liittynyt: Ke Tammi 21, 2009 14:16

ViestiKirjoittaja soijuv » To Maalis 29, 2012 21:30

2012. Yleisesti sanotaan että borrelia-bakteeri sirtyy punkista ihmiseen vasta 36-48 tunnin kuluttua ihoon kiinnittymisestä. Bakteerin on kuitenkin havaittu siirtyvän tätä nopeammin, alle vuorokaudessa kiinnittymisestä. Terveydenhuollossa tulee ottaa huomioon lyhyen tartunta-ajan mahdollisuus.


Diagn Microbiol Infect Dis. 2012 Feb;72(2):188-92. Epub 2011 Nov 21
.
Clinical evidence for rapid transmission of Lyme disease following a tickbite.

Hynote ED, Mervine PC, Stricker RB.

Source

International Lyme and Associated Diseases Society1, Bethesda, MD 20827-1461, USA.

Abstract

Lyme disease transmission to humans by Ixodes ticks is thought to require at least 36-48 h of tick attachment. We describe 3 cases in which transmission of Borrelia burgdorferi, the spirochetal agent of Lyme disease, appears to have occurred in less than 24 h based on the degree of tick engorgement, clinical signs of acute infection, and immunologic evidence of acute Lyme disease. Health care providers and individuals exposed to ticks should be aware that transmission of Lyme disease may occur more rapidly than animal models suggest. A diagnosis of Lyme disease should not be ruled out based on a short tick attachment time in a subject with clinical evidence of B. burgdorferi infection.

Copyright © 2012 Elsevier Inc. All rights reserved.
soijuv
 
Viestit: 3097
Liittynyt: Ke Tammi 21, 2009 14:16

ViestiKirjoittaja soijuv » Ke Touko 30, 2012 09:51


Kuinka kauan punkin tulee olla kiinnittyneenä ihoon ennen kuin borreliabakteeri välittyy ihmiseen? Asiasta on olemassa erilaisia näkemyksiä. Joidenkin kannanottojen mukaan mahdollisuus sairastua borrelioosiin on mahdollista välittömästi punkin pureman jälkeen ja joidenkin mukaan punkin tulee olla kiinnittyneenä useista
tunneista päiviin. Yleisimmin kuitenkin nähdään että borreliatartunnan mahdollisuus kasvaa noin vuorokauden kuluttua punkin kiinnittymisestä iholle.

Euroopan Unionin kannanoton mukaan osalla punkeista on borreliabakteereita kuitenkin jo sylkirauhasissaan. Myös Willy Burgdorfer on maininnut asiasta. Hän kertoi Bard Collegessa pidetyssä Borrelioosikongressissa syksyllä 1999 tutkimuksesta jossa 5-10 %:lla punkeista oli spirokeettoja sylkirauhasissaan. Tällaisissa tapauksissa tartunnan voi saada heti pureman jälkeen.


?European Union Concerted Action on Lyme Borreliosis?

These findings show that borrelia can be transmitted by ticks when they start to feed. An explanation for this may be that a proportion of ticks carry borreliae in their salivary glands. Furthermore, a study on gerbils and I. ricinus by other EUCALB participants (Kahl, Gray) has shown that transmission can sometimes occur in less than 24 hours.

http://www.dis.strath.ac.uk/vie/LymeEU/pactin2.htm


Tiivistelmiä muutamista tutkimuksista/artikkeleista:

Ei ole tarkkaa tietoa missä ajassa borreliabakteeri tarttuu punkista ihmiseen


Urban Integrated Pest Management
North Carolina Cooperative Service College of Agriculture and Life Sciences
North Carolina Sate University

Ticks

"The minimum attachment time required for transmission of Lyme disease spirochete is not yet known."

Last Modified: 07/10/96

http://ipmwww.ncsu.edu/urban/cropsci/c1 ... ticks.html


3h

California Department of Health Services
Centers for Disease Control and Prevention
Disease Fact Sheets J through L

Lyme Disease
(tick-borne borreliosis, Lyme arthritis)

If removal occurs within three hours of attachment, the risk of tick-
borne infection is reduced.

http://www.dhs.cahwnet.gov/disease/disease5.html


Disseminoitunut taudinkuva 6h kuluttua tarttumisesta

Disseminated Lyme disease after short-duration tick bite
Patmas MA, Remorca C
JSTD 1994; 1:77-78

Abstract:
Lyme disease, an Ixodes tick-borne spirochetal infection, has been the subject of much controversy. One problematic area has been the prophylactic treatment of deer-tick bites in endemic areas. Some have argued against routine antimicrobial prophylaxis based upon the belief that transmission of Borrelia burgdorferi is unlikely before 24-48 hours of tick attachment. Others have suggested that it is cost effective to administer prophylactic antibiotics against Lyme disease when embedded deer-tick bites occur in endemic areas. Herein, a case of disseminated Lyme disease after only 6 hours of
tick attachment is presented. The current recommendation against treatment of short-duration tick bites may need reconsideration, particularly in hyperendemic areas. Color pictures.

Muutamien tuntien sisällä

Preliminary studies on virus and spirochete accumulation in the cement plug of ixodid ticks.
Exp Appl Acarol 1996 Dec;20(12):713-23
Alekseev AN; Burenkova LA; Vasilieva IS; Dubinina HV
Chunikhin SP
Zoological Institute, Russian Academy of Sciences, St Petersburg,
Russia. ana@21sp.spb.su

ABSTRACT:
We provide evidence that tick-borne encephalitis virus and Borrelia
burgdorferi s.l. are accumulated in the cement plug in the host skin within the first few hours after tick attachment. Extirpation of the tick without the cement plug, even very soon after the attachment, did not prevent the transmission by Ixodes ricinus, Ixodes persulcatus or Dermacentor reticulatus to mice. This was within 1 hour in the case of the TBE virus and after 20-22 h of attachment, in the case of Borrelia and I. persulcatus. The epidemiological significance of these findings is discussed.
NLM PUBMED CIT. ID:
9004495 NLM CIT. ID: 97158223

http://www.ncbi.nlm.nih.gov:80/entrez/q ... t=Abstract

8h
Differential spirochetal infectivities to vector ticks of mice chronically infected by the agent of Lyme disease.
J Clin Microbiol 1995 Dec;33(12):3164-8
Shih CM; Liu LP; Spielman A
Department of Parasitology and Tropical Medicine, National Defense
Medical Center, Taipei, Taiwan, Republic of China.

ABSTRACT:
We determined whether the infectivity of the Lyme disease spirochete (Borrelia burgdorferi) to vector ticks varies with the duration of infection in laboratory mice. Thus, noninfected nymphal deer ticks were permitted to feed on two strains of early (2 months after infection) and late (8 months after infection) spirochete-infected
mice. The attached ticks were removed from their hosts at specified time intervals and were thereafter examined for spirochetes by direct immunofluorescence microscopy. Spirochetes can be acquired by nymphal ticks as fast as 8 h after attachment. More than 80% of the attached ticks acquired spirochetal infection within 48 h after feeding on early spirochete-infected mice. In contrast, spirochetal infectivity to ticks was less than 50% after feeding on late spirochete-infected mice. The overall infectivity of spirochete-infected mice to ticks correlated with the duration of tick attachment. In addition, there was no adverse effect on the spirochetal infectivity to ticks by high levels of host antibody against spirochetes, and no obvious differences in infectivity to ticks was observed by the site of tick feeding. We conclude that the span of spirochetal infectivity to ticks varies with the duration of infection in mice and suggest that spirochetes may persist and may be evenly distributed in the skin of infected hosts, regardless of prominent host immunity.
NLM PUBMED CIT. ID: 8586694 NLM CIT. ID: 96156120

http://www.ncbi.nlm.nih.gov:80/entrez/q ... t=Abstract


Useita tunteja

The principal arthropod vectors of disease. What are the risks of travellers' to be bitten? To be infected?
Soc Pathol Exot 1998;91(5 Pt 1-2):467-73
Coosemans M; Van Gompel A
Institut de medecine tropicale Prince Leopold, Anvers, Belgique.

ABSTRACT:
Many blood-sucking arthropods are potential vectors of disease. To become a vector, the arthropod must be susceptible to the infective agent and must survive the incubation period so as to transmit the pathogens to a host. While some arthropod associated diseases affect only man (e.g. malaria) most of these diseases are (anthropo-) zoonoses with man often an accidental host. The risk of contamination depends on the one hand on the biting behaviour of the vector, its biology and distribution, and on the other hand on the sites visited by the traveller, the length of his stay, his activities, the conditions of sleeping accommodation. The risk of contracting malaria is very high in tropical Africa, in the forest area of South America and South East Asia, in Papua New Guinea. Malaria can be prevented if measures (e.g. pyrethroid impregnated bed nets, repellents) are taken to avoid bites of Anopheline mosquitoes between sunset and sunrise, but appropriate chemoprophylaxis must not be neglected. Lethal cases of yellow fever among unvaccinated travellers still occur despite a strict international regulation on vaccination requirements. Dengue is a major health problem in intertropical areas. As no vaccine is available, personal protection measures are recommended against daytime-biting mosquitoes, including the use of protective clothing, repellents. Other arthropod borne diseases among travellers are less common but the risks increase during adventure trips (e.g. zoonotic leishmaniasis, tick-borne relapsing fever) and humanitarian actions (e.g. risk of louse-borne typhus during visits of overcrowded prisons). Tick-borne diseases receive nowadays more attention. These diseases are not only restricted to some occupations (farmers, veterinarians) but also ramblers and campers are at risk. Attached ticks should be removed rapidly and carefully, since several hours of attachment are needed for transmission of spirochetes of LYME disease.
NLM PUBMED CIT. ID: 10078389 NLM CIT. ID: 99178115Bull http://www.ncbi.nlm.nih.gov:80/entrez/q ... t=Abstract

Alle 24h
TITLE: Unusual features in the epidemiology of Lyme borreliosis.
AUTHOR: Angelov L
AUTHOR AFFILIATION:
Medical University, Plovdiv, Bulgaria.
ABSTRACT:
In this study two cases of Lyme borreliosis are presented. First, the author describes how he contracted Lyme borreliosis 24 hours after he visited an endemic area. The second case described is that of a woman who developed Lyme borreliosis symptoms, when intestinal content of an infected tick came into contact with her conjunctiva. In both cases the diagnosis is based on clinical picture and positive serological tests. The first case shows the probability of contracting Lyme borreliosis when the duration of the tick's attachment to the skin is less than 24 hours. The second case, described demonstrates transmission of B. burgdorferi by contact.
NLM
PUBMED CIT. ID: 8817171 NLM CIT. ID: 96414111
SOURCE: Eur J Epidemiol 1996 Feb;12(1):9-11

http://www.ncbi.nlm.nih.gov:80/entrez/q ... t=Abstract


OURCE: FILIATION: borrelia bakteerin suoraan iholle ja sieltä se eteni muutaman päivän aikana muualle elimistöön 24h
Cultivation of Borrelia burgdorferi from human tick bite sites:
a guide to the risk of infection.
J Am Acad Dermatol 1995 Feb;32(2 Pt 1):184-7
Berger BW; Johnson RC; Kodner C; Coleman L
Department of Dermatology, State University of New York at Stony
Brook.

ABSTRACT:
The risk of acquiring Lyme disease has been evaluated by xenodiagnostic procedures with laboratory strains of Borrelia burgdorferi and laboratory-reared Ixodes ticks, or by clinical trials in which diagnosis was based on clinical findings, culture, or serologic tests. OBJECTIVE: Our purpose was to determine the risk of infection from tick bites in a natural setting in which wild strains of B. burgdorferi were involved, by a biopsy culture technique.
METHODS: Skin biopsy specimens were obtained from Ixodes scapularis tick bite sites, processed, and examined for the presence of B. burgdorferi. RESULTS: B. burgdorferi was cultivated from only 2 of 48 skin biopsy specimens. In both instances duration of tick attachment was approximately 24 hours. CONCLUSION: In a hyperendemic region for Lyme disease the risk of infection after a deer tick bite appears to be low, particularly if the tick has been attached for less than 24 hours.
NLM PUBMED CIT. ID: 7829700 NLM CIT. ID: 95130771
http://www.ncbi.nlm.nih.gov:80/entrez/q ... t=Abstract

Mahdollinen 24h - riski tämän jälkeen suurenee

Duration of tick attachment and Borrelia burgdorferi transmission.
Piesman J; Mather TN; Sinsky RJ; Spielman A
J Clin Microbiol 1987 Mar;25(3):557-8

ABSTRACT:
Nymphal Ixodes dammini transmitted Borrelia burgdorferi to 1 of 14 rodents exposed for 24 h, 5 of 14 rodents exposed for 48 h, and 13 of 14 rodents exposed for greater than or equal to 72 h. Prompt removal of attached ticks is a prudent public health measure, especially in regions where Lyme disease is endemic.
NLM PUBMED CIT. ID: 3571459 NLM CIT. ID: 87195350
http://www.ncbi.nlm.nih.gov:80/entrez/q ... t=Abstract

Suurin riski jos yli 24h

Prevention of Lyme disease.
Am J Hosp Pharm 1992 May;49(5):1164-73
Couch P; Johnson CE
College of Pharmacy, University of Michigan (UM), Ann Arbor.

ABSTRACT:
Lyme disease and the use of tick repellents and physical protective measures to prevent the disease are discussed. Lyme disease is a multiple-organ-system, immune-mediated inflammatory disorder transmitted by the bites of ixodid ticks infected with Borrelia burgdorferi. An individual is at greatest risk for infection when a tick has been attached to the skin for more than 24 hours. Lyme disease occurs in three stages and may affect the skin, nervous system, cardiac system, and joints. Antimicrobials used in management consist primarily of penicillins, cephalosporins, tetracyclines, and erythromycin. Tick repellents are divided into those applied to the skin and those applied to clothing. Skin repellents include N,N-diethyl-meta-toluamide (DEET), 2-ethyl-1,3-hexanediol, and dimethyl phthalate. Permethrin is by far the most effective clothing repellent. DEET plus a permethrin-containing clothing repellent offers the best overall protection. The adverse effects of repellents are minimal, but cases of hypersensitivity have been reported, especially in children. Physical measures to prevent tick bites include avoiding tick-infested areas, wearing light-colored clothing for easy identification of crawling ticks, regularly checking the body and pets for ticks, wearing protective garments and closed-toed shoes, and removing attached ticks promptly by using tweezers or forceps to apply a steady upward pull. A vaccine for the active immunization of humans against Lyme disease remains to be developed. Although antimicrobial therapy is available for persons with Lyme disease, the best approach for those who may be exposed to infected ticks is to apply topical skin or clothing repellents and to practice common-sense measures of physical protection.
NLM PUBMED CIT. ID: 1595748 NLM CIT. ID: 92280866
http://www.ncbi.nlm.nih.gov:80/entrez/q ... t=Abstract

48h
Duration of adult female Ixodes dammini attachment and transmission of Borrelia burgdorferi, with description of a needle aspiration isolation method.
J Infect Dis 1991 Apr;163(4):895-7
Piesman J; Maupin GO; Campos EG; Happ CM
Division of Vector-Borne Infectious Diseases, Centers for Disease
Control, Ft. Collins, CO 80522.

ABSTRACT:
The relationship between the attachment duration of adult female Ixodes dammini and the transmission of Borrelia burgdorferi was studied. Sixteen rabbits were exposed to spirochete-infected female ticks for specified intervals. All five rabbits exposed to ticks that fed to repletion (greater than 120 h) became infected, as did two of three exposed for 48 h. In contrast, five rabbits exposed to a cumulative total of 53 infected female I. dammini for 36 h failed to become infected, as did three rabbits exposed for 24 h. A needle aspirate method facilitated the isolation of spirochetes from host skin.
NLM PUBMED CIT. ID: 2010643 NLM CIT. ID: 91185898
http://www.ncbi.nlm.nih.gov:80/entrez/q ... t=Abstract

48h
Prospects for suppressing transmission of Lyme disease.
Ann N Y Acad Sci 1988;539:212-20
Spielman A
Department of Tropical Public Health, Harvard School of Public Health,
Boston, Massachusetts 02115.

ABSTRACT:
A variety of methods have been developed to prevent human infection by the Lyme disease spirochete in the northeastern United States, mainly based on the observations that nymphal Ixodes dammini serve as vector, that deer serve as hosts for the reproductive stage of this tick, that white-footed mice serve as the reservoir of infection, and that nymphs are most abundant in early summer and must attach for 2 days before infection is transmitted. Methods for personal protection included seasonal avoidance of infested sites, the use of repellants, and prompt removal of attached ticks. Destruction of mouse habitat, but not of mice, was locally effective. Nondestructive acaricidal treatment of deer proved ineffective, but the elimination of these hosts resulted in reduced transmission after several years. Treatment of mice by means of acaricide-impregnated bedding material effectively reduced transmission.
NLM PUBMED CIT. ID: 3190093 NLM CIT. ID: 89048794

http://www.ncbi.nlm.nih.gov:80/entrez/q ... t=Abstract

48h jälkeen

Duration of tick bites in a Lyme disease-endemic area.
Falco RC; Fish D; Piesman J
Am J Epidemiol 1996 Jan 15;143(2):187-92
Vector Ecology Laboratory, Calder Ecology Center, Fordham University,
Armonk, NY 10504,
USA.

ABSTRACT:
Regression equations, based on scutal index (body length/scutal width), were developed to determine the duration of attachment for nymphal and adult female lxodes scapularis ticks. Feeding times were calculated for 444 nymphal and 300 female ticks submitted by bite victims between 1985 and 1989 in Westchester County, New York, an area where Lyme disease is highly endemic. Nymphs were attached for a mean of 34.7 hours, with 26.8% removed after 48 hours, the critical time for transmission of Borrelia burgdorferi. Attachment times increased with victim age class (Kruskal-Wallis test, p < 0.05). Mean duration of attachment for female ticks (28.7 hours) was significantly less (Kruskal-Wallis test, p < 0.05) than that for nymphs, with 23.3% attached for more than 48 hours. The 0- to 9-year age class had the highest proportion (37.1%) of females attached for more than 48 hours. Nymphs remain attached to adult tick-bite victims longer than they remain attached to children. However, children have a high risk of acquiring Lyme disease because they receive more nymphal bites and also because they are less likely to have female ticks removed in time to prevent transmission.
NLM PUBMED CIT. ID: 8546120 NLM CIT. ID: 96138331

http://www.ncbi.nlm.nih.gov:80/entrez/q ... t=Abstract

Suurentunut riski jos yli 72h

Duration of tick attachment as a predictor of the risk of Lyme disease in an area in which Lyme disease is endemic.
J Infect Dis 1997 Apr;175(4):996-9
Sood SK; Salzman MB; Johnson BJ; Happ CM; Feig K
Carmody L; Rubin LG; Hilton E; Piesman J
Department of Medicine, Long Island Jewish Medical Center and
Albert Einstein College of Medicine, New Hyde Park, New York, USA.

ABSTRACT:
Animal studies have shown an exponential increase in the risk of Borrelia burgdorferi infection after 48-72 h of deer tick attachment. Persons with tick bites were prospectively studied to determine if those with prolonged tick attachment constitute a high-risk group for infection. Ticks were identified, measured for engorgement, and assayed by polymerase chain reaction (PCR) for B. burgdorferi DNA. Duration of attachment was determined from the scutal index of engorgement. Of 316 submissions, 229 were deer ticks; 14% were positive by PCR. Paired sera and an intact tick for determination of duration of attachment were available for 105 subjects (109 bites). There were 4 human cases (3.7% of bites) of B. burgdorferi infection. The incidence was significantly higher for duration of attachment > or =72 h than for <72 h: 3 (20%) of 15 vs. 1 (1.1%) of 94 (P = .008; odds ratio, 23.3; 95% confidence interval, 2.2-242). PCR was an unreliable predictor of infection. Tick identification and
measurement of engorgement can be used to identify a small, high-risk subset of persons who may benefit from antibiotic prophylaxis.
NLM PUBMED CIT. ID: 9086168 NLM CIT. ID: 97240708
http://www.ncbi.nlm.nih.gov:80/entrez/q ... t=Abstract

Jos punkki on iholla yli 72 h, vaara sairastua borrelioosiin on 20-kertainen

Long Island Jewish Medical Center Study Shows Lyme Disease Risk Linked to Length of Time Tick is Attached to Skin
June 1997

*Patients 20 times more likely to get Lyme disease if tick on skin for 72 hours

New Hyde Park, NY... A study at Schneider Children's Hospital (SCH) of Long Island Jewish Medical Center (LIJ) shows that people bitten by a deer tick are 20 times more likely to contract Lyme disease if the tick remains undetected on their skin for 72 hours or more. The findings, published in The Journal of Infectious Diseases, April edition, showed that the incidence of infection following a tick bite is one to three percent. However, if the tick has been on the skin for 72 hours, the risk of contracting Lyme Disease jumps to 20 percent.

"The study illustrates the importance of checking yourself and your children for ticks if you're in an area where Lyme disease is prevalent," said Sunil Sood, MD, the pediatric Lyme disease specialist who conducted the research. "Removing a tick correctly, that is, using tweezers and getting as close to the skin as possible when pulling it off, can mean the difference between contracting Lyme disease and avoiding it."

How do you know how long a tick has been on your skin? The laboratory at the Children's Hospital is available to analyze ticks brought in by the public. "If the lab finds that it is indeed a deer tick and that it was attached for 72 hours, patients will be advised on whether they should receive antibiotics as a precautionary measure," said Dr. Sood.

http://www.lij.edu/news/lyme_disease.html

Punkit välittävät borreliabakteerin suoraan iholle ja sieltä se etenee muutaman päivän sisällä eri puolille elimistöä

Delayed dissemination of Lyme disease spirochetes from the site of deposition in the skin of mice.
J Infect Dis 1992 Oct;166(4):827-31
Shih CM; Pollack RJ; Telford SR 3d; Spielman A
Department of Tropical Public Health, Harvard School of Public Health,
Boston, Massachusetts 02115.

ABSTRACT:
To determine whether the agent of Lyme disease disseminates in vertebrate hosts directly after deposition by an infecting tick, a 6-mm disk of skin was excised from the sites where nymphal Ixodes dammini ticks infected by Lyme disease spirochetes, Borrelia burgdorferi, had fed. Infection in each mouse was tested by examining xenodiagnostic ticks that had engorged on these mice 4 weeks later and by serologic testing. Generalized infection was aborted when the site of inoculation was excised within 2 days after the infecting tick detached but not after 2 weeks. In contrast, all mice became infected when the bite site remained intact. Spirochetes could be cultured from the tissues around the site of attachment solely when the sample was ablated within a week after infecting ticks detached. These observations suggest that infecting ticks deliver the agent of Lyme disease directly into the skin and that such spirochetes multiply locally for some days before disseminating to remote sites.
NLM PUBMED CIT. ID: 1527418 NLM CIT. ID: 92407384
http://www.ncbi.nlm.nih.gov:80/entrez/q ... t=Abstract
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