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Medically important ixodid ticks often carry multiple pathogens, with individual ticks frequently coinfected and capable of transmitting multiple infections to hosts, including humans. Acquisition of multiple zoonotic pathogens by immature blacklegged ticks (Ixodes scapularis) is facilitated when they feed on small mammals, which are the most competent reservoir hosts for Anaplasma phagocytophilum (which causes anaplasmosis in humans), Babesia microti (babesiosis) and Borrelia burgdorferi (Lyme disease). Here, we used data from a large-scale, long-term experiment to ask whether patterns of single and multiple infections in questing nymphal I. scapularis ticks from residential neighbourhoods differed from those predicted by independent assortment of pathogens, and whether patterns of coinfection were affected by residential application of commercial acaricidal products. Quantitative polymerase chain reaction was used for pathogen detection in multiplex reactions. In control neighbourhoods and those treated with a fungus-based biopesticide deployed against host-seeking ticks (Met52), ticks having only single infections of either B. microti or B. burgdorferi were significantly less common than expected, whereas coinfections with these 2 pathogens were significantly more common. However, use of tick control system bait boxes, which kill ticks attempting to feed on small mammals, eliminated the bias towards coinfection. Although aimed at reducing the abundance of host-seeking ticks, control methods directed at ticks attached to small mammals may influence human exposure to coinfected ticks and the probability of exposure to multiple tick-borne infections.

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Although human exposure to the ticks that transmit Lyme-disease bacteria is widely considered to occur around people's homes, most studies of variation in tick abundance and infection are undertaken outside residential areas. Consequently, the patterns of variation in risk of human exposure to tick-borne infections in these human-dominated landscapes are poorly understood. Here, we report the results of four years of sampling for tick abundance, tick infection, tick encounters, and tick-borne disease reports on residential properties nested within six neighborhoods in Dutchess County, New York, USA, an area of high incidence for Lyme and other tick-borne diseases. All properties were within neighborhoods that had been randomly assigned as placebo controls in The Tick Project; hence, none were treated to reduce tick abundance during the period of investigation, providing a unique dataset of natural variation within and between neighborhoods. We estimated the abundance of host-seeking blacklegged ticks (Ixodes scapularis) in three types of habitats on residential properties-forests, lawns, and gardens. In forest and lawn habitats, some neighborhoods had consistently higher tick abundance. Properties within neighborhoods also varied consistently between years, suggesting hot spots and cold spots occurring at a small (~ 1-hectare) spatial scale. Across neighborhoods, the abundance of nymphal ticks was explained by neither the amount of forest in that neighborhood, nor by the degree of forest fragmentation. The proportion of ticks infected with three common tick-borne pathogens did not differ significantly between neighborhoods. We observed no effect of tick abundance on human encounters with ticks, nor on either human or pet cases of tick-borne diseases. However, the number of encounters between ticks and outdoor pets in a neighborhood was negatively correlated with the abundance of questing ticks in that neighborhood. Our results reinforce the need to understand how human behavior and neglected ecological factors affect variation in human encounters with ticks and cases of tick-borne disease in residential settings.

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Background: Controlling populations of ticks with biological or chemical acaricides is often advocated as a means of reducing human exposure to tick-borne diseases. Reducing tick abundance is expected to decrease immediate risk of tick encounters and disrupt pathogen transmission cycles, potentially reducing future exposure risk. Materials and Methods: We designed a placebo-controlled, randomized multiyear study to assess whether two methods of controlling ticks-tick control system (TCS) bait boxes and Met52 spray-reduced tick abundance, tick encounters with people and outdoor pets, and reported cases of tick-borne diseases. The study was conducted in 24 residential neighborhoods in a Lyme disease endemic zone in New York State. We tested the hypotheses that TCS bait boxes and Met52, alone or together, would be associated with increasing reductions in tick abundance, tick encounters, and cases of tick-borne disease over the 4-5 years of the study. Results: In neighborhoods with active TCS bait boxes, populations of blacklegged ticks (Ixodes scapularis) were not reduced over time in any of the three habitat types tested (forest, lawn, shrub/garden). There was no significant effect of Met52 on tick abundance overall, and there was no evidence for a compounding effect over time. Similarly, we observed no significant effect of either of the two tick control methods, used singly or together, on tick encounters or on reported cases of tick-borne diseases in humans overall, and there was no compounding effect over time. Thus, our hypothesis that effects of interventions would accumulate through time was not supported. Conclusions: The apparent inability of the selected tick control methods to reduce risk and incidence of tick-borne diseases after years of use requires further consideration.

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Acaricides are hypothesized to reduce human risk of exposure to tick-borne pathogens by decreasing the abundance and/or infection prevalence of the ticks that serve as vectors for the pathogens. Acaricides targeted at reservoir hosts such as small mammals are expected to reduce infection prevalence in ticks by preventing their acquisition of zoonotic pathogens. By reducing tick abundance, reservoir-targeted or broadcast acaricides could reduce tick infection prevalence by interrupting transmission cycles between ticks and their hosts. Using an acaricide targeted at small-mammal hosts (TCS bait boxes) and one sprayed on low vegetation (Met52 fungal biocide), we tested the hypotheses that infection prevalence of blacklegged ticks with zoonotic pathogens would be more strongly diminished by TCS bait boxes, and that any effects of both acaricidal treatments would increase during the four years of deployment. We used a masked, placebo-controlled design in 24 residential neighborhoods in Dutchess County, New York. Analyzing prevalence of infection with Borrelia burgdorferi, Anaplasma phagocytophilum, and Babesia microti in 5380 nymphal Ixodes scapularis ticks, we found little support for either hypothesis. TCS bait boxes did not reduce infection prevalence with any of the three pathogens compared to placebo controls. Met52 was associated with lower infection prevalence with B. burgdorferi compared to placebo controls but had no effect on prevalence of infection with the other two pathogens. Although significant effects of year on infection prevalence of all three pathogens were detected, hypothesized cumulative reductions in prevalence were observed only for B. burgdorferi. We conclude that reservoir-targeted and broadcast acaricides might not generally disrupt pathogen transmission between reservoir hosts and tick vectors or reduce human risk of exposure to tick-borne pathogens.

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Tickborne diseases (TBDs) such as Lyme disease result in ≈500,000 diagnoses annually in the United States. Various methods can reduce the abundance of ticks at small spatial scales, but whether these methods lower incidence of TBDs is poorly understood. We conducted a randomized, replicated, fully crossed, placebo-controlled, masked experiment to test whether 2 environmentally safe interventions, the Tick Control System (TCS) and Met52 fungal spray, used separately or together, affected risk for and incidence of TBDs in humans and pets in 24 residential neighborhoods. All participating properties in a neighborhood received the same treatment. TCS was associated with fewer questing ticks and fewer ticks feeding on rodents. The interventions did not result in a significant difference in incidence of human TBDs but did significantly reduce incidence in pets. Our study is consistent with previous evidence suggesting that reducing tick abundance in residential areas might not reduce incidence of TBDs in humans.

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INTRODUCTION: Pharyngo-oesophageal stricturing is common following treatment of head and neck cancers. Absolute dysphagia secondary to total stenosis, although rare, is particularly debilitating and presents a significant therapeutic challenge. We present a strategy for managing total neopharyngeal stenosis following pharyngolaryngo-oesophagectomy (PLOG). PRESENTATION OF CASE: A 71-year-old female developed total neopharyngeal stenosis following PLOG with gastric interposition for squamous cell carcinoma of the proximal cervical oesophagus/post-cricoid. A transcervical, percutaneous, radiologically guided procedure was performed to restore lumenal patency, which enabled resumption of oral feeding. DISCUSSION: Established treatments for pharyngo-oesophageal strictures are frequently limited by complications in patients with complex strictures or total stenoses. Whilst several interventions have been described, recent interest has focussed on combined antegrade/retrograde endoscopic procedures dilating a pre-existing gastrostomy site for access. This was not possible in our patient due to the surgically altered anatomy which posed a unique therapeutic challenge. CONCLUSION: This is the first reported percutaneous, transcervical, radiologically guided technique to treat neopharyngeal stenosis following PLOG. It demonstrates a novel and efficacious approach which may be considered in the management of this rare but significant complication.

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This retrospective observational study aimed to establish the outcome for patients packed with a nasal tampon as first-line therapy for epistaxis in Accident & Emergency compared to those packed by ENT. During our study period, 189 admissions were treated with a nasal tampon as first-line therapy; 89 were inserted by ENT and 100 by A&E. A significantly higher number of patients packed by A&E required further treatment to control bleeding (p = 0.004; 95 per cent CI 7-34) than those in the group packed by ENT. A significantly greater proportion from the A&E group required additional cautery alone to control bleeding (p = 0.005; 95 per cent CI 5-30). We suggest that this may be due to inadequate initial assessment and inappropriate first-line therapy in the A&E department. It is recommended that ENT review patients prior to packing, in order to reduce the morbidity associated with multiple treatments.

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BACKGROUND: Lyme disease is a vector-borne infectious disease, accounting for more than 95% of all reported vector-borne illness in the United States. From 1992 2000, Dutchess County reported more cases of Lyme disease than any other county in the United States, consistently ranking among the top ten in incidence rates. We analyzed 1992-2000 Dutchess County Lyme disease surveillance data to characterize Lyme disease trends, identify high-risk populations, and examine the frequency of the characteristic lesion, erythema migrans. METHODS: A Lyme disease case was defined as a person with physician-diagnosed erythema migrans or at least one late manifestation of the disease, with laboratory confirmation. A surveillance database of cases reported in Dutchess County from 1992-2000 was obtained from the New York State Department of Health. Annual incidence rates by age, gender, race, ethnicity, and ZIP codes, and frequency of erythema migrans were calculated. RESULTS: From 1992 through 2000, a total of 9,548 cases of Lyme disease were reported by Dutchess County to the New York State Department of Health, for a crude mean annual incidence rate of 400 cases per 100,000 persons per year. The incidence rate peaked at 683/100,000 in 1996, and then declined from 1998 to 2000. A bimodal age distribution was seen, with the initial peak among children aged 5-9 years (617/100,000) and the second peak among adults aged 60-64 years (627/100,000). A male preponderance was clearly seen between the ages of 5-19 years, and beyond the age of 60 years. Highest incidence rates were reported in central Dutchess County. Onset of illness occurred most frequently in June, July, and August. Ninety-four percent of cases occurred among the predominantly white population, which had the highest incidence rate (431/100,000) among the races. Incidence rate for non-Hispanics was more than double that for Hispanics. Eighty-one percent of reported cases had erythema migrans. CONCLUSIONS: While some prevention programs could be broadly targeted to the entire Dutchess County population, other interventions might be most effective if they focused on the high-risk population groups and areas defined in this report. The high proportion of cases with erythema migrans suggests that early diagnosis and treatment should be effective in reducing late-stage complications of Lyme disease in Dutchess County. Surveillance data for other endemic counties and states can be similarly analyzed to enhance and monitor local prevention programs.

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