The nymphal stage of the blacklegged tick, Ixodes scapularis (Acari: Ixodidae), is responsible for most transmission of Borrelia burgdorferi, the etiologic agent of Lyme disease, to humans in North America. From 2010 to fall of 2012, we compared two commonly used techniques, flagging and dragging, as sampling methods for nymphal I. scapularis at three sites, each with multiple sampling arrays (grids), in the eastern and central United States. Flagging and dragging collected comparable numbers of nymphs, with no consistent differences between methods. Dragging collected more nymphs than flagging in some samples, but these differences were not consistent among sites or sampling years. The ratio of nymphs collected by flagging vs dragging was not significantly related to shrub density, so habitat type did not have a strong effect on the relative efficacy of these methods. Therefore, although dragging collected more ticks in a few cases, the numbers collected by each method were so variable that neither technique had a clear advantage for sampling nymphal I. scapularis.

Lyme disease also called ,,the illness with a thousand faces" ("The Great Imitator") because it may mimic very well the symptoms and signs of other diseases, is an unusual medical encounter for the urologist. Every patient with Lyme disease has his own clinical feature, while the superposition over an unknown but easy to discover urological disease may lead to a misdiagnosis.Male patient A. P. was an emergency transfer in our clinic with multiple system organ failure. The mirage of first imaging finding, bilateral obstructive ureteral calculi was obviated after the serological confirmation of Lyme disease suspected after the thorough history obtained from his family. The intensive care treatment, broad-spectrum antibiotics and hemodialysis sessions, together with external urinary drainage, lead to the improvement of the patient status, and subsequent proper urological treatment to urolithiasis cure.This case identifies several challenges faced by practitioners, challenges which involve the diagnosis and the treatment of Lyme disease associated with urolithiasis. Although Lyme disease remains a controversial clinical entity, its diagnosis is based on a history of possible exposure to ticks, the appearance of specific clinical symptoms, whether or not combined with serological tests.

Lipid rafts in eukaryotic cells are sphingolipid and cholesterol-rich, ordered membrane regions that have been postulated to play roles in many membrane functions, including infection. We previously demonstrated the existence of cholesterol-lipid-rich domains in membranes of the prokaryote, B. burgdorferi, the causative agent of Lyme disease [LaRocca et al. (2010) Cell Host & Microbe 8, 331-342]. Here, we show that these prokaryote membrane domains have the hallmarks of eukaryotic lipid rafts, despite lacking sphingolipids. Substitution experiments replacing cholesterol lipids with a set of sterols, ranging from strongly raft-promoting to raft-inhibiting when mixed with eukaryotic sphingolipids, showed that sterols that can support ordered domain formation are both necessary and sufficient for formation of B. burgdorferi membrane domains that can be detected by transmission electron microscopy or in living organisms by Förster resonance energy transfer (FRET). Raft-supporting sterols were also necessary and sufficient for formation of high amounts of detergent resistant membranes from B. burgdorferi. Furthermore, having saturated acyl chains was required for a biotinylated lipid to associate with the cholesterol-lipid-rich domains in B. burgdorferi, another characteristic identical to that of eukaryotic lipid rafts. Sterols supporting ordered domain formation were also necessary and sufficient to maintain B. burgdorferi membrane integrity, and thus critical to the life of the organism. These findings provide compelling evidence for the existence of lipid rafts and show that the same principles of lipid raft formation apply to prokaryotes and eukaryotes despite marked differences in their lipid compositions.

The selection of controls is an important methodological consideration for case-control studies. Neighborhood-matched control selection is particularly crucial for studies of vector-borne disease, such as Lyme disease, for which risk is intrinsically linked to geographical location. The matching of case-control pairs on neighborhood can help control for variation in ecological risk factors that are tied to geographical location, like vector and host habitat in the peridomestic environment. Random-digit dialing has been used to find neighborhood controls by using the area code and exchange of the case to generate lists of potential control households. An alternative to random-digit dialing is the purchase of residential telephone numbers from a commercial marketing database. This report describes the utility of the InfoUSA.com (InfoGroup, Papillion, Nebraska) commercial marketing database for neighborhood control recruitment in a Lyme disease case-control study in Connecticut during 2005-2007.

Lyme disease is a tick-borne infection caused by the transmission of Borrelia burgdorferi from infected Ixodes ticks to a mammalian host during the blood meal. Previous studies have shown that the expression of B. burgdorferi surface-localized lipoproteins, which include BBA64, is up-regulated during the process of tick feeding. Although the exact function of BBA64 is not known, this lipoprotein is critical for the transmission of the spirochete from the tick salivary glands to the mammalian organism after a tick bite. Since the mechanism of development of the disease and the functions of the surface lipoproteins associated with borreliosis are still poorly understood, the crystal structure of the B. burgdorferi outer surface lipoprotein BBA64 was solved at 2.4 Å resolution in order to obtain a better insight into the pathogenesis of B. burgdorferi and to promote the discovery of novel potential preventive drugs against Lyme disease. In this study, the crystal structure of BBA64 was also compared with that of the paralogous protein CspA (also referred to as BbCRASP-1, CRASP-1 or BBA68). CspA is the complement regulator-acquiring surface protein-1 of B. burgdorferi; its structure is known, but its function apparently differs from that of BBA64. It is demonstrated that unlike the homologous CspA, BBA64 does not form a homodimer. Their differences in function could be explained by divergence in their amino-acid sequences, electrostatic surface potentials and overall tertiary structures. The C-terminal part of BBA64 has a different conformation to that of CspA; the conformation of this region is essential for the proper function of CspA.

In the United States, 30,158 people were reported as having contracted Lyme disease during 2010; 96% of the cases in 2011 were reported from 13 northeast and north-central states. Time of tick attachment is a critical factor. Prolonged attachment allows time for a bacterium to move from tick to human. Patient history and meticulous skin inspection are the most important elements used in diagnosis of Lyme disease. The most common drug for treatment is doxycycline. Ticks find their hosts by several senses: odor, moisture, heat, and vibration. Avoidance of tick-infested areas, such as wooded areas and leaf piles, is paramount in preventing Lyme disease.

BACKGROUND:

Lyme disease is commonly diagnosed in humans in Latvia, but up to date no studies have been performed to investigate its prevalence in dogs. The aim of this study was to evaluate if seroprevalence against B. burgdorferi sensu lato (B. burgdorferi s.l.) and co-expression of antibodies against B.burgdorferi s.l. and A. phagocytophilum is higher in dogs with clinical suspicion of tick-borne diseases compared to healthy dogs.

FINDINGS:

Venous blood was taken from healthy dogs (n=441) and dogs suspected to have borreliosis and/ or canine granulocytic anaplasmosis (n=29). The presence of antibodies was detected with SNAP 4Dx test (IDEXX, Westbrook, Maine, USA). The seroprevalence against B. burgdorferi s.l. in healthy dogs was 2.49% (11/441) and 36% (4/11) of seropositive dogs had antibodies against both of investigated bacteria. None of the dogs in sick dog group had detectable antibodies against B. burgdorferi s.l.

CONCLUSIONS:

We conclude that seroprevalence to B. burgdorferi s.l. in dogs in Latvia is low and that dogs with suspicion of tick-borne disease do not have higher B. burgdorferi s. l. seroprevalence than healthy dogs. Dogs that express antibodies against B. burgdorferi s.l. frequently co-express antibodies against A. phagocytophilum.

Borrelia burgdorferi, the causative agent of Lyme disease, must adapt to two diverse niches, an arthropod vector and a mammalian host. RpoS, an alternative sigma factor, plays a central role in spirochetal adaptation to the mammalian host by governing expression of many genes important for mammalian infection. B. burgdorferi is known to be unique in metal utilization and little is known of the role of biologically available metals in B. burgdorferi. Here, we identified two transition metal ions, manganese (Mn(2+)) and zinc (Zn(2+)), that influenced regulation of RpoS. The intracellular Mn(2+) level fluctuated approximately 20-fold under different conditions, and inversely correlated with levels of RpoS and the major virulence factor OspC. Furthermore, an increase in intracellular Mn(2+) repressed temperature-dependent induction of RpoS and OspC; this repression was overcome by an excess of Zn(2+). Conversely, a decrease of intracellular Mn(2+) by deletion of the Mn(2+) transporter, bmtA, resulted in elevated levels of RpoS and OspC. Mn(2+) affected RpoS through BosR, a Fur family homolog that is required for rpoS expression: elevated intracellular Mn(2+) levels greatly reduced the level of BosR protein, but not the level of bosR mRNA. Thus, Mn(2+) and Zn(2+) appeared to be important in modulation of the RpoS pathway that is essential to the life cycle of the Lyme disease spirochete. This finding supports the emerging notion that transition metals such as Mn(2+) and Zn(2+) play a critical role in regulation of virulence in bacteria.

Lyme disease is a multi-systemic disorder caused by Borrelia burgdorferi infection. Upon infection, some B. burgdorferi genes are up-regulated, including members of the microbial surface components recognizing adhesive matrix molecule (MSCRAMM) protein family, which facilitate B. burgdorferi adherence to extracellular matrix components of the host. Comparative genome analysis has revealed a new family of B. burgdorferi proteins containing the von Willebrand factor A (vWFA) domain. In the present study, we characterized the expression and membrane association of the vWFA domain-containing protein BB0172, using in vitro transcription/translation systems in the presence of microsomal membranes, and detergent phase separation assays. Our results show evidence of BB0172 localization in the outer membrane, the orientation of the vWFA domain to the extracellular environment, and its function as a metal ion-dependent integrin-binding protein. This is the first report of a borrelial adhesin with a metal ion-dependent adhesion site (MIDAS) motif that is similar to those observed in eukaryotic integrins and has a similar function.