rate of Bb from bites of infected ticks:
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
risk of Borrelia burgdorferi sensu lato from Ixodes ricinus ticks to humans in
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 PMID: 9747761
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
, 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
is higher than previously assumed. Examination of ticks and antibiotic
prophylaxis in the case of positivity appears to be indicated.
of Bb after short duration tickbite (<24h):
story reported by Marie Kroun at a staffmeeting in
, 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 her in
, except for scientific purposes. The only test available is the ELISA
Lyme disease after short-duration tick bite
MA, Remorca C.
Journal of Spirochetal and Tickborne Diseases 1994; 1:77-78 [Not listed on
PubMed, have scanned to PDF]
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.
features in the epidemiology of Lyme borreliosis.
Eur J Epidemiol 1996 Feb; 12(1): 9-11 PMID: 8817171
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.
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.
O, Janetzki Mittmann C, Gray JS, Jonas R, Stein J, de Boer R.
Zentralbl Bakteriol 1998 Jan; 287(1-2): 41-52 PMID:
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
ricinus feeding. There is no evidence from this study that the
tick removal method used has any significant influence on a host's
studies on virus and spirochete accumulation in the cement plug of ixodid
AN, Burenkova LA, Vasilieva IS, Dubinina HV, Chunikhin SP.
Exp Appl Acarol 1996 Dec; 20(12): 713-23 PMID: 9004495
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
persulcatus. The epidemiological significance of these findings is discussed.
Lyme borreliosis: 231 culture-confirmed cases involving patients with erythema
Nelson JA, Ruzic Sabljic E, Cimperman J.
Clin Infect Dis 1996 Jul; 23(1): 61-5. PMID: 8816130
In 1994, we isolated Borrelia burgdorferi sensu lato from 231 patients with
erythema migrans who presented to the University Medical Center in Ljubljana,
Slovenia. Samples of erythema migrans-affected skin were placed in media to
support the growth of Borrelia species and evaluated in Ljubljana and Chicago.
Patients whose cultures were positive included 132 women and 99 men; 136 of
these 231 patients recalled a tick bite. Patients noted a rash an average of
24 days after a bite and presented a mean of 34 days after the bite with
erythema migrans (mean diameter. 16 cm). Itching (44%) burning (18%), and pain
(11%) were the most common local symptoms. Systemic complaints (40%) included
headache, fatigue, malaise, and arthralgia. Other than erythema migrans,
findings on physical examination were minimal (< 5% had fever, and in <
10% local lymph nodes were affected). Serial serological studies using
indirect immunofluorescence assay, ELISA, and Western blot methods were
performed, and antibodies to B, burgdorferi sensu lato were detected in <
50% of samples from patients. This is the largest series reported to date of
patients with culture-confirmed Lyme borreliosis. It highlights the
deficiencies of serological tests in early disease, demonstrates the
sensitivity of direct detection methods for evaluation of patients with
erythema migrans, and suggests that patients with early Lyme borreliosis in
Slovenia may suffer a milder illness than those in the United States.
Of the 467
skin biopsy specimens, 231 (49%) yielded B. burgdorferi sensu lato. ... Only
four of the patients had received antimicrobials before biopsy. ...
majority of the rashes had central clearing (71%), but a fairly large group
demonstrated a homogeneous erythema (29%). Rashes appeared most often on the
legs (62%). The most common local symptom was pruritus (45%), and the most
frequent systemic complaint was headache (20%). Multiple EM lesions (6%) and
additional physical examination findings were unusual. Of the 136 patients
who recalled a tick bite, the majority noted their rash several weeks
following the bite (mean, 24 days; median, 17 days). Figure 1 shows the
seasonal nature of this disease and summarizes the months in which patients
recalled their bites, noticed the EM, and presented for care. ...
patients in our series reported having EM previously. At
least six of these patients had evidence of IgG antibodies to B. burgdorfen
sensu lato on presentation, yet they were not protected from a second
occurrence of EM. Western blotting was performed on samples from four
of these patients. Two samples contained antibodies
to outer surface protein A (OspA), and three showed evidence of antibodies
to OspC. It is unclear whether or not these patients may have been
afforded some protection against disseminated disease, but local disease
developed despite the previous occurrence of disease and the presence of
some immune memory.
[in 25] disease transmission occurred despite a tick attachment time of
tick attachment time 34 (15%)
<6 h 9 (4%)
<24 h 16 (7%)
Of <48 h
patients had received brief courses of antimicrobials and yet their
specimens still yielded Borrelia organisms. ... This suggests that a few
doses of antimierobials will not necessarily preclude culture of the
organisms from skin specimens
... The lack
of maturation of the serological response in our study ...
... The Western
blot method with use of B. burgdorferi sensu stricto was most sensitive.
of our patients developed a serological response to infection. ... It
may be that B. afzelii has less potential to disseminate early in the
burgdorferi sensu lato in female cement plug of Ixodes persulcatus ticks (Acari,
AN, Arumova EA, Vasilieva IS.
Exp Appl Acarol 1995 Sep; 19(9): 519-22 PMID: 8575271
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
transmission of Lyme disease spirochetes by partially fed vector ticks.
CM, Spielman A.
J Clin Microbiol 1993 Nov; 31(11): 2878-81 PMID: 8263171
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.
of Borrelia burgdorferi isolated from different organs of Ixodes ricinus ticks
collected in nature.
Garcia S, Kramer MD, Wallich R, Gern L.
Int J Med Microbiol Virol Parasitol Infect Dis 1994 Mar; 280(4): 468-75
Borrelia burgdorferi was isolated from 22 out of 133 adult Ixodes ricinus
ticks collected from vegetation at two sites in
. 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
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
presence of Borrelia in the intestines and salivary glands of spontaneously
infected adult Ixodes persulcatus Schulze ticks during bloodsucking]
GG, Korenberg EI, Gorban' Lia.
Med Parazitol Mosk 1995 Jul-Sep(3): 16-20 PMID: 7476674
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
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.(ABSTRACT
TRUNCATED AT 250 WORDS)
frequency of generalized infection in adult fasting ticks of the genus Ixodes
in foci of borreliosis in
GG, Korenberg EI, Spielman A, Shchegoleva TV.
Parazitologiia 1995 Sep-Oct; 29(5): 353-60 PMID: 8524615
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
I. persulcatus and 26.3 +/-
dammini. However, the proportions
of ticks with generalized infections differ considerably (12.9 +/-
I. persulcatus compared with 2.4 +/-
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
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
differences found here among different tick species may explain the different
findings of transmission rate in US and in the 'old world' ... need to
know more about Ixodes ricinus, the common vector in EU]