Ecology and Epidemiology of Tickborne Pathogens, Washington, USA, 2011-2016.

Tickborne diseases are rare in Washington, USA, and the ecology of these pathogens is poorly understood. We integrated surveillance data from humans and ticks to better describe their epidemiology and ecology. During 2011-2016, a total of 202 tickborne disease cases were reported in Washington residents. Of these, 68 (34%) were autochthonous, including cases of Lyme disease, Rocky Mountain spotted fever, tickborne relapsing fever, and tularemia. During May 2011-December 2016, we collected 977 host-seeking ticks, including Ixodes pacificus, I. angustus, I. spinipalpis, I. auritulus, Dermacentor andersoni, and D. variabilis ticks. The prevalence of Borrelia burgdorferi sensu stricto in I. pacificus ticks was 4.0%; of B. burgdorferi sensu lato, 3.8%; of B. miyamotoi, 4.4%; and of Anaplasma phagocytophilum, 1.9%. We did not detect Rickettsia rickettsii in either Dermacentor species. Case-patient histories and detection of pathogens in field-collected ticks indicate that several tickborne pathogens are endemic to Washington.

Lyme Disease Diagnosed by Alternative Methods: A Phenotype Similar to That of Chronic Fatigue Syndrome.

BACKGROUND: A subset of patients reporting a diagnosis of Lyme disease can be described as having alternatively diagnosed chronic Lyme syndrome (ADCLS), in which diagnosis is based on laboratory results from a nonreference Lyme specialty laboratory using in-house criteria. Patients with ADCLS report symptoms similar to those reported by patients with chronic fatigue syndrome (CFS). METHODS: We performed a case-control study comparing patients with ADCLS and CFS to each other and to both healthy controls and controls with systemic lupus erythematosus (SLE). Subjects completed a history, physical exam, screening laboratory tests, 7 functional scales, reference serology for Lyme disease using Centers for Disease Control and Prevention criteria, reference serology for other tick-associated pathogens, and cytokine expression studies. RESULTS: The study enrolled 13 patients with ADCLS (12 of whom were diagnosed by 1 alternative US laboratory), 25 patients with CFS, 25 matched healthy controls, and 11 SLE controls. Baseline clinical data and functional scales indicate significant disability among ADCLS and CFS patients and many important differences between these groups and controls, but no significant differences between each other. No ADCLS patient was confirmed as having positive Lyme serology by reference laboratory testing, and there was no difference in distribution of positive serology for other tick-transmitted pathogens or cytokine expression across the groups. CONCLUSIONS: In British Columbia, a setting with low Lyme disease incidence, ADCLS patients have a similar phenotype to that of CFS patients. Disagreement between alternative and reference laboratory Lyme testing results in this setting is most likely explained by false-positive results from the alternative laboratory.

Current trend on syphilis diagnosis: issues and challenges.

Syphilis is a century old sexually transmitted infection transmitted worldwide. WHO reports 12 million new cases that were identified in 1999, with over 90% of these infections reported from patients from low-income countries. This case number of syphilis is on the rise globally in the Men have sex with Men (MSM) population. Dark field microscopy (DFM) and direct fluorescence assay (DFA) have been used in clinical laboratories for decades to demonstrate Treponema pallidum in acutely infected human tissue and/or body fluids. Molecular technologies allow detecting T. pallidum and also determine drug resistance (by identifying DNA point mutation). It is evident from the published literature that PCR is useful as an adjunct test to DFA and DFM, and is useful in confirming syphilis in genital ulcer, tissue, and other body fluid samples, providing even more sensitive detection algorithm. Serological tests remain the mainstay tests since T. pallidum is nonculturable and also because blood collection is easy. The practice of serological testing is changing rapidly from traditional nontreponemal screening followed by confirmatory treponemal testing to screening by treponemal tests referred to as "Reverse Algorithm" followed by nontreponemal testing to determine active infections. Special and further complex algorithms are essential to deal with complex issues such as neurosyphilis or congenital syphilis. Due to the huge surge of syphilis in developing countries where access to medical care is not optimal, point of care or rapid tests may play an important role. This author took an attempt to summarize the current trend of syphilis diagnosis and challenges from a global perspective.

Rational design of antigens to improve the serodiagnosis of tick-borne borreliosis in central regions of Russia.

Tick-borne borreliosis (Lyme disease-LD) is caused by pathogenic Borrelia spirochetes that is transmitted through bite of Ixodes ticks to humans and animals. In the Russian Federation, borreliosis registered with an index of 6-7 per 100,000 people annually. In reality, LD morbidity in Russia is much higher because Russian strains develop less erythematous rashes compared to North American strains, thus missed by physicians in most of the early cases, and current serology tests have insufficient sensitivity as well. The aim of this work was to improve the sensitivity and specificity of serology tests for LD in Russia using rationale-designed Borrelia antigens. It was anticipated that sensitivity of LD sero-diagnosis will be higher if antigen for test-systems are derived from a strain that is circulated in a geographical region of test application. A large portion of the Russian population lives in the Central region. Thus, effort has been made to create a serological test using antigens from Moscow region, Tula and Ul'janovsk areas. In this study we included wild strains (ultrasonic-treated spirochetes B. garinii H19, B. afzelii P1, B. afzelii P1H13, B. burgdorferi s.s. 39/40, B. burgdorferi s.s. B31), recombinant (expressed in E.coli DbpA, Bgp, Bbk B. garinii, and B. afzelii) antigens and some of their combinations were produced and tested against LD patients and donors serum collected in hospitals of Central regions of Russia by ELISA and Western blotting. Considering sensitivity and specificity, DbpA B. afzelii and DbpA B. garinii recombinant antigens were selected among all probed antigens for regional serology test. As long as DbpA B. afzelii and DbpA B. garinii antigens interacted with LD patient's serum in a complementary mode, it is possible to combine epitopes DbpA B. afzelii and B. garinii in a single antigen for improving sensitivity. We created recombinant fusion protein DbpA B. afzelii/B using dbpA genes from Russian isolates of B. afzelii and B. garinii in E. coli. Fusion DbpA A + G protein was then used for formulation of fast immunochromatographic serodiagnosis test (LF) in a "deep-stick" format. The trials of LF-test were conducted separately at Institute of Rheumatology Russian Academy of Medical Science (using 325 sera) and at the Borreliosis Reference Center of Ministry of Health RF (using 120 reference sera). The average sensitivity and specificity of LF-test was 80.5 and 100 %, respectively.

Draft whole-genome sequences of three Borrelia burgdorferi isolates from Western Canada.

Whole-genome sequences are presented for three Borrelia burgdorferi, a causative agent of Lyme disease in North America, isolated from Ixodes pacificus ticks collected in British Columbia, Canada. Shotgun DNA libraries were prepared with Illumina DNA Prep and sequenced using the MiniSeq platform. Genome assemblies enabled multilocus sequence typing and ospC typing.

Whole-genome sequencing of Western Canadian Borrelia spp. collected from diverse tick and animal hosts reveals short-lived local genotypes interspersed with longer-lived continental genotypes.

Changing climates are allowing the geographic expansion of ticks and their animal hosts, increasing the risk of Borrelia-caused zoonoses in Canada. However, little is known about the genomic diversity of Borrelia from the west of the Canadian Rockies and from the tick vectors Ixodes pacificus, Ixodes auritulus and Ixodes angustus. Here, we report the whole-genome shotgun sequences of 51 Borrelia isolates from multiple tick species collected on a range of animal hosts between 1993 and 2016, located primarily in coastal British Columbia. The bacterial isolates represented three different species from the Lyme disease-causing Borrelia burgdorferi sensu lato genospecies complex [Borrelia burgdorferi sensu stricto (n=47), Borrelia americana (n=3) and Borrelia bissettiae (n=1)]. The traditional eight-gene multi-locus sequence typing (MLST) strategy was applied to facilitate comparisons across studies. This identified 13 known Borrelia sequence types (STs), established 6 new STs, and assigned 5 novel types to the nearest sequence types. B. burgdorferi s. s. isolates were further differentiated into ten ospC types, plus one novel ospC with less than 92 % nucleotide identity to all previously defined ospC types. The MLST types resampled over extended time periods belonged to previously described STs that are distributed across North America. The most geographically widespread ST, ST.12, was isolated from all three tick species. Conversely, new B. burgdorferi s. s. STs from Vancouver Island and the Vancouver region were only detected for short periods, revealing a surprising transience in space, time and host tick species, possibly due to displacement by longer-lived genotypes that expanded across North America.This article contains data hosted by Microreact.

New proteins for a new perspective on syphilis diagnosis.

Syphilis is a sexually transmitted disease caused by Treponema pallidum subsp. pallidum; it can be effectively treated with penicillin yet remains prevalent worldwide, due in part to the shortcomings of current diagnostic tests. Here we report the production of soluble recombinant versions of three novel diagnostic candidate proteins, Tp0326, Tp0453, and a Tp0453-Tp0326 chimera. The sensitivities of these recombinant proteins were assessed by screening characterized serum samples from primary, secondary, and latent stages of infection (n = 169). The specificities were assessed by screening false positives identified with the standard diagnostic testing algorithm (n = 21), samples from patients with potentially cross-reactive infections (Leptospira spp., Borrelia burgdorferi, Helicobacter pylori, Epstein-Barr virus, hepatitis B virus, hepatitis C virus, or cytomegalovirus) (n = 38), and samples from uninfected individuals (n = 11). The sensitivities of Tp0326, Tp0453, and the Tp0453-Tp0326 chimera were found to be 86%, 98%, and 98%, respectively, and the specificities were 99%, 100%, and 99%. In a direct comparison, the Captia syphilis (T. pallidum)-G enzyme immunoassay (Trinity Biotech) was used to screen the same serum samples and was found to have a sensitivity of 98% and a specificity of 90%. In particular, Tp0453 and the chimera exhibited superior accuracy in classifying analytical false-positive samples (100%, compared to 43% for the Captia assay). These findings identify Tp0453 and the Tp0453-Tp0326 chimera as novel syphilis-specific diagnostic candidates that surpass the performance of a currently available diagnostic enzyme immunoassay test for syphilis and that allow accurate detection of all stages of infection.

Surveillance for Ixodes scapularis and Ixodes pacificus ticks and their associated pathogens in Canada, 2019.

Background: The primary vectors of the agent of Lyme disease in Canada are Ixodes scapularis and Ixodes pacificus ticks. Surveillance for ticks and the pathogens they can transmit can inform local tick-borne disease risk and guide public health interventions. The objective of this article is to characterize passive and active surveillance of the main Lyme disease tick vectors in Canada in 2019 and the tick-borne pathogens they carry. Methods: Passive surveillance data were compiled from the National Microbiology Laboratory Branch and provincial public health data sources. Active surveillance was conducted in selected sentinel sites in all provinces. Descriptive analysis of ticks submitted and infection prevalence of tick-borne pathogens are presented. Seasonal and spatial trends are also described. Results: In passive surveillance, specimens of I. scapularis (n=9,858) were submitted from all provinces except British Columbia and I. pacificus (n=691) were submitted in British Columbia and Alberta. No ticks were submitted from the territories. The seasonal distribution pattern was bimodal for I. scapularis adults, but unimodal for I. pacificus adults. Borrelia burgdorferi was the most prevalent pathogen in I. scapularis (18.8%) and I. pacificus (0.3%). In active surveillance, B. burgdorferi was identified in 26.2% of I. scapularis; Anaplasma phagocytophilum in 3.4% of I. scapularis, and Borrelia miyamotoi and Powassan virus in 0.5% or fewer of I. scapularis. These same tick-borne pathogens were not found in the small number of I. pacificus tested. Conclusion: This surveillance article provides a snapshot of the main Lyme disease vectors in Canada and their associated pathogens, which can be used to monitor emerging risk areas for exposure to tick-borne pathogens.

Passive Tick Surveillance and Detection of Borrelia Species in Ticks from British Columbia, Canada: 2002-2018.

Lyme disease, caused by Borrelia burgdorferi sensu lato (s.l.) complex, is the most common vector-borne disease in North America. This disease has a much lower incidence in western compared with eastern North America. Passive tick surveillance data submitted over 17 years from 2002 to 2018 were analyzed to determine the occurrence of tick species and the prevalence of Borrelia spp. in ticks in British Columbia (BC), Canada. The BC Centre for Disease Control Public Health Laboratory received tick submissions from physicians, veterinarians, and BC residents. Ticks were identified to species, and all ticks, except Dermacentor andersoni, were tested using generic B. burgdorferi s.l. primer sets and species-specific PCR primer sets for B. burgdorferi sensu stricto (s.s.). Tick submission data were analyzed to assess temporal and geographical trends, tick life stages, and tick species. Poisson regression was used to assess temporal trends in annual tick submissions. A total of 15,464 ticks were submitted. Among these, 0.29% (n = 10,235) of Ixodes spp. ticks and 5.3% (n = 434) of Rhipicephalus sanguineus ticks were found carrying B. burgdorferi s.s. B. burgdorferi s.s. was primarily detected in Ixodes pacificus (52%; n = 16) and Ixodes angustus ticks (19%; n = 6) retrieved from humans (n = 5) and animals (n = 26). B. burgdorferi was found in ticks submitted throughout the year. Ixodes spp. ticks were primarily submitted from the coastal regions of southwestern BC, and D. andersoni ticks were primarily submitted from southern interior BC. The number of human tick submissions increased significantly (p < 0.001) between 2013 and 2018. The annual prevalence of B. burgdorferi in ticks remained stable during the study period. These findings correspond to those observed in US Pacific Northwestern states. Passive tick surveillance is an efficient tool to monitor long-term trends in tick distribution and B. burgdorferi prevalence in a low endemicity region.

Comprehensive Immune Profiling of a Kidney Transplant Recipient With Peri-Operative SARS-CoV-2 Infection: A Case Report.

To date there is limited data on the immune profile and outcomes of solid organ transplant recipients who encounter COVID-19 infection early post-transplant. Here we present a unique case where the kidney recipient's transplant surgery coincided with a positive SARS-CoV-2 test and the patient subsequently developed symptomatic COVID-19 perioperatively. We performed comprehensive immunological monitoring of cellular, proteomic, and serological changes during the first 4 critical months post-infection. We showed that continuation of basiliximab induction and maintenance of triple immunosuppression did not significantly impair the host's ability to mount a robust immune response against symptomatic COVID-19 infection diagnosed within the first week post-transplant.

Global phylogeny of Treponema pallidum lineages reveals recent expansion and spread of contemporary syphilis.

Syphilis, which is caused by the sexually transmitted bacterium Treponema pallidum subsp. pallidum, has an estimated 6.3 million cases worldwide per annum. In the past ten years, the incidence of syphilis has increased by more than 150% in some high-income countries, but the evolution and epidemiology of the epidemic are poorly understood. To characterize the global population structure of T. pallidum, we assembled a geographically and temporally diverse collection of 726 genomes from 626 clinical and 100 laboratory samples collected in 23 countries. We applied phylogenetic analyses and clustering, and found that the global syphilis population comprises just two deeply branching lineages, Nichols and SS14. Both lineages are currently circulating in 12 of the 23 countries sampled. We subdivided T. p. pallidum into 17 distinct sublineages to provide further phylodynamic resolution. Importantly, two Nichols sublineages have expanded clonally across 9 countries contemporaneously with SS14. Moreover, pairwise genome analyses revealed examples of isolates collected within the last 20 years from 14 different countries that had genetically identical core genomes, which might indicate frequent exchange through international transmission. It is striking that most samples collected before 1983 are phylogenetically distinct from more recently isolated sublineages. Using Bayesian temporal analysis, we detected a population bottleneck occurring during the late 1990s, followed by rapid population expansion in the 2000s that was driven by the dominant T. pallidum sublineages circulating today. This expansion may be linked to changing epidemiology, immune evasion or fitness under antimicrobial selection pressure, since many of the contemporary syphilis lineages we have characterized are resistant to macrolides.

Cryptococcus gattiivgi in a spinner dolphin (Stenella longirostris) from Hawaii.

A spinner dolphin (Stenella longirostris) was found stranded in Hawaii with cutaneous nodules and enlarged lymph nodes. Numerous Cryptococcus gattii VGI yeast were observed in multiple organs with minimal inflammation. This case represents the first reported infection of C. gattii in a dolphin from Hawaii.

Detection of 'Candidatus Ehrlichia khabarensis' in rodents and ticks removed from rodents in British Columbia, Canada.

'Candidatus Ehrlichia khabarensis' was first described from rodents and insectivores in the Far East territory of Khabarovsk on the Russian Pacific Coast. Here we report the detection of DNA from this microorganism in rodents and fed ticks collected from rodents in British Columbia, Canada in 2013-2014. 'Candidatus Ehrlichia khabarensis' was detected in (i) a female Ixodes angustus tick collected from a Peromyscus maniculatus; (ii) a female Dermacentor andersoni tick collected from a Perognathus parvus; (iii) a pool of 2 larval Ixodes pacificus ticks collected from a single P. maniculatus; and (iv) a pool of 3 nymphal I. pacificus ticks collected from a single P. maniculatus. Three of these four rodents (2 P. maniculatus and 1 P. parvus) with infected ticks also had evidence of 'Candidatus Ehrlichia khabarensis' in at least one tissue type. The infected P. maniculatus and Ixodes ticks came from the Vancouver area in western British Columbia and the P. parvus and Dermacentor tick from an inland site in central British Columbia. Although it remains to be determined whether 'Candidatus Ehrlichia khabarensis' has any negative impacts on wildlife, domestic animals or humans, we note that all three tick species found to contain the DNA of this microorganism are known to bite humans. Future detection of this microorganism either in ticks collected from rodents and allowed to molt to the next life stage prior to being tested, or from host-seeking ticks, is required to determine if it can survive the tick's molt after being ingested via an infectious blood meal.

Spread of Cryptococcus gattii into Pacific Northwest region of the United States.

Cryptococcus gattii has emerged as a human and animal pathogen in the Pacific Northwest. First recognized on Vancouver Island, British Columbia, Canada, it now involves mainland British Columbia, and Washington and Oregon in the United States. In Canada, the incidence of disease has been one of the highest worldwide. In the United States, lack of cryptococcal species identification and case surveillance limit our knowledge of C. gattii epidemiology. Infections in the Pacific Northwest are caused by multiple genotypes, but the major strain is genetically novel and may have emerged recently in association with unique mating or environmental changes. C. gattii disease affects immunocompromised and immunocompetent persons, causing substantial illness and death. Successful management requires an aggressive medical and surgical approach and consideration of potentially variable antifungal drug susceptibilities. We summarize the study results of a group of investigators and review current knowledge with the goal of increasing awareness and highlighting areas where further knowledge is required.

Baylisascariasis: A young boy with neural larva migrans due to the emerging raccoon round worm.

A 17-month-old boy from Vancouver, Canada, presented with a 5-day history of progressive somnolence, ataxia, and torticollis. Additional investigations revealed eosinophilic encephalitis with deep white matter changes on MR imaging. On day 13, serology came back positive for Baylisascaris procyonis antibodies. While prophylaxis after ingestion of soil or materials potentially contaminated with raccoon feces can prevent baylisascariasis, timely treatment can sometimes alter a disastrous outcome. Populations of infected raccoons are propagating globally, but cases of Baylisascaris neural larva migrans have so far only been reported from North America.

Neurosyphilitic gumma in a homosexual man with HIV infection confirmed by polymerase chain reaction.

The brain gumma is a rare manifestation of the tertiary stage of syphilis. A case of neurosyphilitic gumma was confirmed by the Treponema pallidum polymerase chain reaction in a 46-year-old HIV-positive homosexual man. The patient presented with a severe headache and was hospitalized. A computed tomography scan was performed which revealed a left frontal lobe mass. Lymphoma was suspected. However, infectious disease diagnostics were performed on the cerebrospinal fluid that included investigations for syphilis and other microbiological agents such as Toxoplasma gondii. This revealed a reactive venereal disease research laboratory test, a reactive syphilis rapid plasma reagin and a reactive T. pallidum particle agglutination test. The patient was treated for syphilis till complete recovery.

Low prevalence of Helicobacter pylori infection in Canadian children: a cross-sectional analysis.

BACKGROUND: The incidence and prevalence rates of childhood Helicobacter pylori infection vary greatly by nation, with infection rates of 8.9% to 72.8% reported in developed and developing countries, respectively. To date, few studies have assessed the prevalence of H pylori in Canadian children, with studies limited to Aboriginal communities and single tertiary care centres from Ontario and Quebec. OBJECTIVES: To determine the prevalence of H pylori in consecutive children referred to three Canadian tertiary care academic centres for upper gastrointestinal (GI) endoscopy due to upper GI symptoms, and to determine the sensitivity and specificity of the carbon-13-labelled urea breath test, the rapid urease test and the H pylori stool monoclonal antigen test. RESULTS: Two hundred four patients were recruited. The prevalence of H pylori was 7.1%. Of the H pylori-positive patients, 41.7% were male, with a mean age of 10.3 years. Ethnic minorities accounted for 42% of the H pylori-positive patients. Consistent with previous observations, the sensitivity and specificity of the carbon-13-labelled urea breath test were 1.0 and 0.98, respectively. The sensitivity and specificity of the rapid urease test were 1.0 and 0.99, respectively. Stool samples were collected from 34 patients from one centre, with a sensitivity and specificity of 1.0 and 0.68, respectively. No defining symptoms of H pylori infection were evident and no peptic ulcer disease was demonstrated. CONCLUSION: H pylori infection rates in Canadian children with upper GI symptoms are low, and are lower than those reported for other developed countries. Further studies are required in Canada to determine the prevalence in the general population and specifically in the populations at risk.

Rapid introduction of Lyme disease spirochete, Borrelia burgdorferi sensu stricto, in Ixodes scapularis (Acari: Ixodidae) established at Turkey Point Provincial Park, Ontario, Canada.

Borrelia burgdorferi sensu stricto (s.s.) was isolated from questing adult Ixodes scapularis Say ticks collected from Turkey Point Provincial Park (TPPP), Ontario, Canada during 2005-2006. DNA from ten (67%) of 15 pools of ticks was confirmed positive for B. burgdorferi s.s. using polymerase chain reaction (PCR) by targeting the rrf (5S)-rrl (23S) intergenic spacer region and OspA genes. This significant infection rate indicates an accelerated development of B. burgdorferi s.s. in TPPP, because this pathogen was not detected five years previously during sampling of the three motile life stages of I. scapularis. Our study provides the initial report of the presence of B. burgdorferi s.s. in TPPP, which is now endemic for Lyme disease. Ultimately, people and domestic animals are at risk of contracting Lyme disease when they frequent this park.