Lyme Disease Prophylaxis by Single-Dose Doxycycline in the United States, 2010-2020.

Single-dose doxycycline after high-risk tick bites can prevent Lyme disease, which disproportionately affects children. We described single-dose doxycycline dispensings in an outpatient cohort in the United States. During 2010-2020, a total of 427 105 patients received ≥1 dispensing(s); most were aged ≥65 years. Lyme disease postexposure prophylaxis may be underprescribed for some groups, including children.

Pregnancy Among Reported Lyme Disease Cases-United States, 1992-2019.

BACKGROUND: Lyme disease (LD), the most common vector-borne disease in the United States, typically presents with a localised erythema migrans rash (EM). Left untreated, infection can disseminate to cause severe heart, joint or nervous system manifestations. Summaries of LD surveillance data have been published previously but did not include the frequency, demographic or clinical characteristics of LD cases during pregnancy. METHODS: We summarised confirmed and probable LD cases by pregnancy status as reported to the U.S. Centers for Disease Control and Prevention during 1992-2019. We defined an LD case during pregnancy as one with (1) female sex, (2) age 14-49 years and (3) positive pregnancy indication. We evaluated the frequency, seasonality, age distribution, race and ethnicity, geographic distribution and clinical manifestations of LD cases during pregnancy and cases among non-pregnant females. We compared proportions using chi-squared tests. RESULTS: Among 698,876 reported LD cases, 112,002 (16%) were confirmed or probable cases among females aged 14-49 years; 32,301 (29%) were specifically reported as non-pregnant and 643 (0.6%) (568 confirmed and 75 probable cases) reported as pregnant. Illness onset peaked in June among LD cases during pregnancy, but in July for cases among non-pregnant females. A higher proportion of confirmed LD cases during pregnancy had only EM rash than did cases among non-pregnant females (66% vs. 60%, p = 0.019). CONCLUSIONS: LD cases during pregnancy are rare. Compared to non-pregnant females, cases among pregnant females more commonly involve early clinical manifestations. These patterns could suggest earlier detection or more complete reporting of LD cases during pregnancy than their non-pregnant counterparts. Earlier detection could be due to frequent contact with healthcare or increased self-advocacy during pregnancy. Prompt antimicrobial treatment is critical for preventing severe disease and reducing risk of adverse pregnancy or birth outcomes.

Barriers to the Uptake of Tickborne Disease Prevention Measures: Connecticut, Maryland 2016-2017.

CONTEXT: Public health programs promote numerous tickborne disease (TBD) prevention measures. However, measures are not frequently or consistently performed. OBJECTIVE: Describe barriers to consistent use of 4 commonly promoted TBD prevention measures. DESIGN: We conducted an online survey (n = 1883) evaluating behaviors regarding TBD prevention measures including conducting tick checks, applying insect repellents, showering/bathing, and applying chemical or natural pesticides to residential yards. Respondents could select reasons for never, rarely, or sometimes performing these measures. Descriptive analysis and logistic regression modeling evaluated associations between the 3 most cited barriers for each measure and select demographic variables. SETTING: The survey was administered to residents in high Lyme disease incidence counties of Connecticut and Maryland, 2016-2017. RESULTS: For tick checks (n = 800), the most cited barriers were forgetting (63%), not spending time in tick habitat (28%), and too much trouble (11%). For applying insect repellents (n = 1303), the most cited barriers were forgetting (38%), personal safety concerns (24%), and too much trouble (19%). For showering/bathing 2 hours after outdoor activity in tick habitat (n = 1080), the most cited barriers were being unaware of the prevention measure (51%), too much trouble (18%), and forgetting (18%). For applying chemical pesticides to yards (n = 1320), the most cited barriers were having environmental (45%), pet safety (31%), and personal safety concerns (28%). Lastly, for applying natural pesticides to yards (n = 1357), the most cited barriers were being unaware of natural pesticides (31%), having cost concerns (23%), and not being concerned about ticks on property (16%). CONCLUSIONS: Forgetting, too much trouble, unawareness, and safety concerns were primary barriers to using several TBD prevention measures. Education regarding effectiveness, safety, and timing may increase uptake of certain measures. These challenges can be difficult to address, highlighting the need for passive TBD prevention measures, such as a Lyme disease vaccine.

Epidemiology of Lyme Disease Diagnoses among Older Adults, United States, 2016-20191.

We used Medicare data to identify >88,000 adults >65 years of age diagnosed and treated for Lyme disease during 2016-2019 in the United States. Most diagnoses occurred among residents of high-incidence states, in summer, and among men. Incidence of diagnoses was substantially higher than that reported through public health surveillance.

Epidemiologic and tick exposure characteristics among people with reported Lyme disease - Minnesota, 2011-2019.

AIMS AND METHODS: In the United States, blacklegged Ixodes spp. ticks are the primary vector of Lyme disease. Minnesota is among the states with the highest reported incidence of Lyme disease, having an average of 1857 cases reported annually during 2011-2019. In contrast to the Northeast and mid-Atlantic United States where exposure to ticks predominately occurs around the home, the circumstances regarding risk for exposure to blacklegged ticks in Minnesota are not well understood, and risk is thought to be highest in rural areas where people often participate in recreational activities (e.g. hiking, visiting cabins). We analysed enhanced surveillance data collected by the Minnesota Department of Health during 2011-2019 to describe epidemiologic and tick exposure characteristics among people with reported Lyme disease. RESULTS: We found that younger age, male gender, residence in a county with lower Lyme disease risk, residence in the Minneapolis-St. Paul metropolitan area, and an illness onset date later in the year were independently associated with higher odds of reporting tick exposures away from the home. We also describe the range of activities associated with tick exposure away from the home, including both recreational and occupational activities. CONCLUSIONS: These findings refine our understanding of Lyme disease risk in Minnesota and highlight the need for heterogeneous public health prevention messaging, including an increased focus on peridomestic prevention measures among older individuals living in high-risk rural areas and recreational and occupational prevention measures among younger individuals living in the Minneapolis-St. Paul metropolitan area.

Knowledge and practices related to louse- and flea-borne diseases among staff providing services to people experiencing homelessness in the United States.

BACKGROUND AND AIMS: Louse-borne Bartonella quintana infection and flea-borne murine typhus are two potentially serious vector-borne diseases that have led to periodic outbreaks among people experiencing homelessness in the United States. Little is known about louse- and flea-borne disease awareness and prevention among staff who provide services to the population. We surveyed staff in seven US states to identify gaps in knowledge and prevention practices for these diseases. METHODS AND RESULTS: Surveys were administered to 333 staff at 89 homeless shelters and outreach teams in California, Colorado, Georgia, Maryland, Minnesota, New York and Washington from August 2022 to April 2023. Most participants (>68%) agreed that body lice and fleas are a problem for people experiencing homelessness. About half were aware that diseases could be transmitted by these vectors; however, most could not accurately identify which diseases. Less than a quarter of staff could describe an appropriate protocol for managing body lice or fleas. Misconceptions included that clients must isolate or be denied services until they are medically cleared. CONCLUSIONS: Our findings reveal significant knowledge gaps among staff who provide services to people experiencing homelessness in the prevention and control of louse- and flea-borne diseases. This demonstrates an urgent need for staff training to both reduce disease and prevent unnecessary restrictions on services and housing.

Surveillance for Lyme Disease After Implementation of a Revised Case Definition - United States, 2022.

Lyme disease, a tickborne zoonosis caused by certain species of Borrelia spirochetes, is the most common vectorborne disease in the United States. Approximately 90% of all cases are reported from 15 high-incidence jurisdictions in the Northeast, mid-Atlantic, and upper-Midwest regions. After the implementation of a revised surveillance case definition in 2022, high-incidence jurisdictions report cases based on laboratory evidence alone, without need for additional clinical information. In 2022, 62,551 Lyme disease cases were reported to CDC, 1.7 times the annual average of 37,118 cases reported during 2017-2019. Annual incidence increased most in older age groups, with incidence among adults aged ≥65 years approximately double that during 2017-2019. The sharp increase in reported Lyme disease cases in 2022 likely reflects changes in surveillance methods rather than change in disease risk. Although these changes improve standardization of surveillance across jurisdictions, they preclude detailed comparison with historical data.

Lyme disease vaccine attitudes and intentions among parents of children aged 5-18 years in the United States.

BACKGROUND: Lyme disease (LD) is the most common vector-borne disease in the United States, with increasing incidence and geographic range. Case incidence peaks among school-aged children. New LD preventives are in clinical trials. METHODS: We conducted an online survey of parents of children aged 5-18 years in states with high or emerging incidence of LD. Our primary outcome was willingness ("definitely" or "probably") for their child to receive an LD vaccine. Our secondary outcome was preference for annual monoclonal antibody injections compared to a 3-dose vaccine series with boosters. Analyses were weighted to reflect parent gender, parent race/ethnicity, and child age by state. RESULTS: Among 1,351 parent respondents, most (68.0 %) would have their child vaccinated against LD, with significantly more being willing in high compared to emerging incidence states (70.4 % versus 63.6 %, p = 0.027). Of parents who were unsure or unwilling, 33.5 % and 16.5 %, respectively, would do so with a provider recommendation. Vaccine safety concerns were among the top reasons for LD vaccine hesitancy. More parents preferred a pre-formed antibody (42.3 %) compared to a 3-dose vaccine series (34.7 %). Significant predictors of willingness to have one's child vaccinated were higher parental education; higher perceived risk of child getting LD; child spending time outdoors daily or weekly; following a regular vaccine schedule; and positive attitude towards vaccines. Significant predictors of preference for monoclonal antibody over a 3-dose vaccine series included prior awareness of LD, living in a rural area, and less positive attitudes towards vaccines. CONCLUSIONS: Two-thirds of parents in high and emerging incidence states would vaccinate their children against Lyme disease. Addressing safety concerns will be important, and a health care provider recommendation could also encourage those who are unsure or unwilling. Given the slight preference for monoclonal antibody over vaccine, particularly in rural areas, access to both may increase LD prevention.

Francisella tularensis Bone and Joint Infections: United States, 2004-2023.

Tularemia is caused by the highly infectious bacterium Francisella tularensis, which is recognized as a Tier 1 bioterrorism agent. Tularemia has a range of recognized clinical manifestations, but fewer than 20 bone or joint infections from 6 countries have been reported in the literature to date. This series includes 13 cases of F. tularensis septic arthritis or osteomyelitis in the United States during 2004-2023 and describes exposures, clinical presentation, diagnosis, and outcomes for this rare but severe form of tularemia. Clinicians should consider F. tularensis in patients with compatible exposures or a history of joint replacement or immunosuppression.

Operational Considerations for Using Deer-Targeted 4-Poster Tick Control Devices in a Tick-borne Disease Endemic Community.

CONTEXT: In the northeastern United States, recommendations to prevent diseases spread by black-legged ticks ( Ixodes scapularis ) and lone star ticks ( Amblyomma americanum ) often rely on individuals to use personal protection or yard-based strategies. The 4-Poster deer treatment stations (4-Posters) suppress tick populations by treating deer hosts with acaricide, potentially offering a community-wide approach for reducing tick-borne diseases in endemic areas. The 4-Poster deployment logistics in mainland community settings are not well documented but are needed for future public health tick control efforts. PROGRAM: As part of a public health research effort to design a population-based 4-Poster effectiveness study aimed at reducing tick-borne disease incidence, TickNET researchers partnered with the Town of Ridgefield (Connecticut) to understand the feasibility and operational logistics of deploying 4-Posters on public land within a residential community to inform future public health interventions by municipalities or vector control agencies. IMPLEMENTATION: We deployed three 4-Posters on a municipal property from July to December 2020 and used motion-activated cameras to record wildlife activity nearby. We documented per-device operational details, costs, materials consumed, and animal activity. EVALUATION: Operation of 4-Posters was feasible, and device challenges were easily remedied. Deer visitation and heavy nontarget animal use were documented at all devices. Unexpectedly, monthly corn consumption was not correlated with monthly deer-view days. The monthly cost per device was US $1279 or US $305 per hectare with an average 21 minutes of weekly service time. DISCUSSION: Use of 4-Posters by communities, public health agencies, or vector control programs may be a practicable addition to tick management programs in tick-borne disease endemic areas in the Northeast. Such programs should carefully consider local and state regulations, follow manufacturer and pesticide label guidelines, and include wildlife monitoring. High labor costs incurred in this project could be mitigated by training vector control agency or municipality staff to service 4-Posters.

Lyme Disease Knowledge, Practices, and Vaccine Acceptability Among Nurse Practitioners in Pediatric Practice.

INTRODUCTION: Lyme disease (LD) is a major public health problem in the United States. Given its incidence and geographic expansion, nurse practitioners (NPs) will likely encounter patients with this condition. METHOD: NPs were invited to participate in an electronic survey via email, newsletter, and social media posts. The 31-question survey collected information on provider characteristics, clinical scenario decisions, resources used, and vaccine sentiment for LD. RESULTS: Survey participants (n = 606) were primarily cisgender female (75%) and aged 30-49 years (62%). Responding to six hypothetical clinical scenarios, only 31% of participants answered most questions correctly. If an LD vaccine becomes available, 39% said they would incorporate it into practice; 48% would seek further information before deciding. DISCUSSION: Additional education on LD prevention, diagnosis, and treatment is needed for NPs. Increasing provider awareness of current guidelines and developing tailored resources for NPs may improve patient care.

Acceptability of 4-poster deer treatment devices for community-wide tick control among residents of high Lyme disease incidence counties in Connecticut and New York, USA.

The 4-Poster Tick Control Deer Feeder (4-poster) device applies acaricide to white-tailed deer (Odocoileus virginianus) and can reduce populations of the blacklegged tick (Ixodes scapularis), which transmits the agents of Lyme disease, anaplasmosis, babesiosis, and Powassan virus disease in the Northeastern United States. While 4-poster devices have the potential to provide community-wide management of blacklegged ticks in Lyme disease endemic areas, no recent study has assessed their acceptability among residents. We conducted a survey of residents from 16 counties with high annual average Lyme disease incidence (≥ 10 cases per 100,000 persons between 2013 and 2017) in Connecticut and New York to understand perceptions and experiences related to tickborne diseases, support or concerns for placement of 4-poster devices in their community, and opinions on which entities should be responsible for tick control on private properties. Overall, 37% of 1652 respondents (5.5% response rate) would support placement of a 4-poster device on their own property, 71% would support placement on other private land in their community, and 90% would support placement on public land. Respondents who were male, rented their property, resided on larger properties, or were very or extremely concerned about encountering ticks on their property were each more likely to support placement of 4-poster devices on their own property. The primary reason for not supporting placement of a 4-poster device on one's own property was the need for weekly service visits from pest control professionals, whereas the top reason for not supporting placement on other land (private or public) was safety concerns. Most respondents (61%) felt property owners should be responsible for tick control on private properties. Communities considering 4-poster devices as part of a tick management strategy should consider targeting owners of larger properties and placing devices on public lands.

Characteristics of Hard Tick Relapsing Fever Caused by Borrelia miyamotoi, United States, 2013-2019.

Borrelia miyamotoi, transmitted by Ixodes spp. ticks, was recognized as an agent of hard tick relapsing fever in the United States in 2013. Nine state health departments in the Northeast and Midwest have conducted public health surveillance for this emerging condition by using a shared, working surveillance case definition. During 2013-2019, a total of 300 cases were identified through surveillance; 166 (55%) were classified as confirmed and 134 (45%) as possible. Median age of case-patients was 52 years (range 1-86 years); 52% were male. Most cases (70%) occurred during June-September, with a peak in August. Fever and headache were common symptoms; 28% of case-patients reported recurring fevers, 55% had arthralgia, and 16% had a rash. Thirteen percent of patients were hospitalized, and no deaths were reported. Ongoing surveillance will improve understanding of the incidence and clinical severity of this emerging disease.

Soft Tick Relapsing Fever - United States, 2012-2021.

Soft tick relapsing fever (STRF) (also known as tickborne relapsing fever) is a rare infection caused by certain Borrelia spirochetes and transmitted to humans by soft-bodied Ornithodoros ticks. In the United States, acquisition of STRF is commonly associated with exposure to rustic cabins, camping, and caves. Antibiotic treatment is highly effective for STRF, but without timely treatment, STRF can result in severe complications, including death. No nationally standardized case definition for STRF exists; however, the disease is reportable in 12 states. This report summarizes demographic and clinical information for STRF cases reported during 2012-2021 from states where STRF is reportable. During this period, 251 cases were identified in 11 states. The median annual case count was 24. Most patients with STRF (55%) were hospitalized; no fatalities were reported. The geographic distribution and seasonal pattern of STRF have remained relatively constant since the 1990s. Persons should avoid rodent-infested structures and rodent habitats, such as caves, in areas where STRF is endemic. STRF surveillance, prevention, and control efforts would benefit from a standardized case definition and increased awareness of the disease among the public and clinicians.

Impacts Over Time of Neighborhood-Scale Interventions to Control Ticks and Tick-Borne Disease Incidence.

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.

Association Between Prolonged Shedding of Zika Virus in Human Semen and Male Reproductive Tract Inflammation.

Zika virus (ZIKV) is a mosquito-borne flavivirus that causes congenital defects. Sexual transmission of ZIKV was confirmed in a recent epidemic; however, mechanisms behind ZIKV infection and persistence in the male reproductive tract (MRT) are unknown. Previously, we found that approximately 33% of men with symptomatic ZIKV infections shed ZIKV RNA in semen, and some men shed ZIKV RNA for >3 months. Here, we evaluated the semen of 49 ZIKV-infected men to identify immune factors correlating with long-term ZIKV shedding in semen and ZIKV-infected cell types in semen. We found that prolonged ZIKV RNA shedding in semen was associated with MRT inflammation, indicated by higher leukocyte counts and inflammatory cytokine concentrations in semen of long-term versus short-term shedders. In addition, we found ZIKV RNA in seminal leukocytes and epithelial cells. This study of human semen from ZIKV-infected men provides critical insights into the effects of ZIKV on MRT health.

Effectiveness of personal protection measures against Lyme disease: A review of epidemiologic studies from the United States.

Lyme disease, the most commonly reported vector-borne disease in the United States, is caused by the bacteria Borrelia burgdorferi and is transmitted through the bite of an infected blacklegged tick. In the absence of a licensed vaccine, the prevention of Lyme disease relies heavily on limiting tick exposure. Methods for limiting tick exposure include personal protection measures such as repellent use, wearing protective clothing, avoiding areas where ticks may be present, bathing after exposure to tick habitat and performing regular tick checks. Public health officials typically recommend all these personal protection measures; however, there is limited evidence to promote one behaviour or practice over another. The focus of this article is to review available literature that examines the effectiveness of recommended personal protection measures to prevent Lyme and other Ixodes-transmitted diseases in humans. Articles included in this review were identified through Google Scholar and PubMed searches using specific search terms. We identified over 56,000 articles using Google Scholar and PubMed searches. Of those, 16 studies fit our criteria for inclusion and were reviewed in their entirety. Among the personal protection measures evaluated, no intervention was predominantly or consistently effective across studies, demonstrating that, currently, there is no single best method for primary prevention of Ixodes-transmitted diseases in the United States. Frequently recommended practices such as tick checks, repellent use and protective clothing had mixed results across studies. Study design differences limited comparability among studies, and sample sizes for these studies may have been too small to detect statistically significant results even if a prevention method was effective. Though many of the reviewed personal protection measures are frequently recommended to the public, limited evidence demonstrates their ability to prevent tick-borne disease. Additional standardized studies are needed to evaluate personal protection measures.

Economic Burden of Reported Lyme Disease in High-Incidence Areas, United States, 2014-2016.

Approximately 476,000 cases of Lyme disease are diagnosed in the United States annually, yet comprehensive economic evaluations are lacking. In a prospective study among reported cases in Lyme disease-endemic states, we estimated the total patient cost and total societal cost of the disease. In addition, we evaluated disease and demographic factors associated with total societal cost. Participants had a mean patient cost of ≈$1,200 (median $240) and a mean societal cost of ≈$2,000 (median $700). Patients with confirmed disseminated disease or probable disease had approximately double the societal cost of those with confirmed localized disease. The annual, aggregate cost of diagnosed Lyme disease could be $345-968 million (2016 US dollars) to US society. Our findings emphasize the importance of effective prevention and early diagnosis to reduce illness and associated costs. These results can be used in cost-effectiveness analyses of current and future prevention methods, such as a vaccine.

Effects of Tick-Control Interventions on Tick Abundance, Human Encounters with Ticks, and Incidence of Tickborne Diseases in Residential Neighborhoods, New York, USA.

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.

Potential quantitative effect of a laboratory-based approach to Lyme disease surveillance in high-incidence states.

Historically, public health surveillance for Lyme disease has required clinical follow-up on positive laboratory reports for the purpose of case classification. In areas with sustained high incidence of the disease, this resource-intensive activity yields a limited benefit to public health practice. A range of burden-reducing strategies have been implemented in many states, creating inconsistencies that limit the ability to decipher trends. Laboratory-based surveillance, or surveillance based solely on positive laboratory reports without follow-up for clinical information on positive laboratory reports, emerged as a feasible alternative to improve standardization in already high-incidence areas. To inform expectations of a laboratory-based surveillance model, we conducted a retrospective analysis of Lyme disease data collected during 2012-2018 from 10 high-incidence states. The number of individuals with laboratory evidence of infection ranged from 1302 to 20,994 per state and year. On average, 55% of those were ultimately classified as confirmed or probable cases (range: 29%-86%). Among all individuals with positive laboratory evidence, 18% (range: 2%-37%) were determined to be 'not a case' upon investigation and 23% (range: 2%-52%) were classified as suspect cases due to lack of associated clinical information and thus were not reported to the Centers for Disease Control and Prevention (CDC). The number of reported cases under a laboratory-based approach to surveillance in high-incidence states using recommended two-tier testing algorithms is likely to be, on average, 1.2 times higher (range: 0.6-1.8 times) than what was reported to CDC during 2012-2018. A laboratory-based surveillance approach for high-incidence states will improve standardization and reduce burden on public health systems, allowing public health resources to focus on prevention messaging, exploration of novel prevention strategies and alternative data sources to yield information on the epidemiology of Lyme disease.