Human Anaplasmosis Research Articles

Detection of serum antibodies to tick-borne and other infections in patients with lymphadenopathy

The aim was to determine the prevalence of serum antibodies to tick-borne pathogens and other infectious agents in patients with lymphadenopathy. Materials and methods. 68 patients with lymphadenopathy aged 20 to 63 years who received outpatient or inpatient treatment were followed up at Ternopil University Hospital and Ternopil Regional Clinical Dermatological and Venereological Dispensary. There were 41 women (60.3 %) and 27 men (39.7 %). Two-stage serological detection (ELISA and immunoblot) was used for diagnosis of Lyme borreliosis (LB). Indirect immunofluorescence, including the BIOCHIP multiplex indirect immunofluorescence technique, was used for serological identification of human granulocytic anaplasmosis (HGA) and other infectious diseases, which could be associated with lymphadenopathy. Results. In total, 45.6 % of 68 enrolled patients were positive for the presence of specific antibodies IgM and/or IgG against B. burgdorferi s. l. Further examination demonstrated the presence of specific serum anti-A. phagocytophilum antibodies IgM and/or IgG in 33 patients with lymphadenopathy. It was found that 24.2 % of involved patients were positive for the presence of at least one type of anti-A. phagocytophilum antibodies; 12.1 % had positive or intermediate results only for B. burgdorferi s. l.; 60.6 % of patients were positive for the presence of antibodies against both pathogens. 46.9 % of patients were seropositive for EBV-CA, 40.6 % – for Parainfluenza virus type 1, 37.5 % – for HHV-6, 34.4 % – for HSV-1, 31.3 % – for EBV-EA and Toxoplasma gondii, 6.3 % – for Coxsackievirus type A9 and HIV-2. Conclusions. One-third of all involved patients with lymphadenopathy were positive for antibodies to B. burgdorferi s. l., causa tive agent of Lyme borreliosis. Co-infection of Lyme borreliosis and human granulocytic anaplasmosis was established in more than half of the patients. Besides, specific antibodies to 18 causative agents of other infectious diseases were detected with varying rate. Almost half of positive results detected were the antibodies to parainfluenza virus type 1 and Epstein–Barr virus.

A Case of Human Granulocytic Anaplasmosis Suspected to be Complicated by Cholangitis

A Case of Human Granulocytic Anaplasmosis Suspected to be Complicated by Cholangitis

Anaplasma phagocytophilum infection rates in questing and host-attached ticks: a global systematic review and meta-analysis

Anaplasma phagocytophilum causes a multi-organ non-specific febrile illness referred to as human granulocytic anaplasmosis. The epidemiologic risk of the pathogen is underestimated despite human encroachment into the natural habitats of ticks. In this study, we performed a systematic review and meta-analysis to determine the global infection rates and distribution of A. phagocytophilum in tick vectors. We pooled data using the random-effects model, assessed individual study quality using the Joanna Briggs Institute critical appraisal instrument for prevalence studies and determined heterogeneity and across study bias using Cochran's Q-test and Egger's regression test respectively. A total of 126 studies from 33 countries across 4 continents reported A. phagocytophilum estimated infection rate of 4.76% (9453/174,967; 95% CI: 3.96, 5.71). Estimated IRs across sub-groups varied significantly (p <0.05) with a range of 1.95 (95% CI: 0.63, 5.86) to 7.15% (95% CI: 5.31, 9.56). Country-based IRs ranged between 0.42 (95% CI: 0.22, 0.80) in Belgium and 37.54% (95% CI: 0.72, 98.03) in Norway. The highest number of studies on A. phagocytophilum were in Europe (82/126) by continent and the USA (33/126) by country. The risk of transmitting this pathogens from ticks to animals and humans exist and therefore, we recommend the use of chemical and biological control measures as well as repellents and protective clothing by occupationally exposed individuals to curtail further transmission of the pathogen to humans and animals.

Epidemiology, Diagnosis, and Control of Canine Infectious Cyclic Thrombocytopenia and Granulocytic Anaplasmosis: Emerging Diseases of Veterinary and Public Health Significance.

This review highlights the diagnostic methods used, the control strategies adopted, and the global epidemiological status of canine cyclic thrombocytopenia and granulocytic anaplasmosis at the animal–human interface. Canine anaplasmosis is an important worldwide disease, mainly caused by Anaplasma platys and A. phagocytophilum with zoonotic implications. A. platys chiefly infects platelets in canids, while A. phagocytophilum is the most common zoonotic pathogen infecting neutrophils of various vertebrate hosts. Diagnosis is based on the identification of clinical signs, the recognition of intracellular inclusions observed by microscopic observation of stained blood smear, and/or methods detecting antibodies or nucleic acids, although DNA sequencing is usually required to confirm the pathogenic strain. Serological cross-reactivity is the main problem in serodiagnosis. Prevalence varies from area to area depending on tick exposure. Tetracyclines are significant drugs for human and animal anaplasmosis. No universal vaccine is yet available that protects against diverse geographic strains. The control of canine anaplasmosis therefore relies on the detection of vectors/reservoirs, control of tick vectors, and prevention of iatrogenic/mechanical transmission. The control strategies for human anaplasmosis include reducing high-risk tick contact activities (such as gardening and hiking), careful blood transfusion, by passing immunosuppression, recognizing, and control of reservoirs/vectors.

Human Granulocytic Anaplasmosis as a COVID-19 Mimicker.

IntroductionHuman granulocytic anaplasmosis (HGA) is a tick-borne illness caused by the bacterium Anaplasma phagocytophilum. HGA has a widely variable clinical presentation and can be life-threatening.Case descriptionA 77-year-old man was transferred from an outside facility with altered mental status, a fever of up to 40.5°C, and shortness of breath. Laboratory analysis revealed a progressively worsening pro-inflammatory state and abnormalities in the patient’s coagulation studies. With clinical and laboratory evidence concerning for potential COVID-19 infection, the patient was placed in isolation as a precaution. The results of two COVID-19 tests, given approximately 24 hours apart, were negative. The patient’s spouse confirmed a bug bite to his upper extremity while working outdoors. His symptoms resolved completely after a 10-day course of empiric doxycycline.DiscussionThe diverse clinical presentations of HGA necessitate a broad differential diagnosis, including viral, bacterial and non-infectious aetiologies. In severe cases, a cytokine-mediated immune cascade can occur (namely, cytokine storm) leading to devastating downstream effects. This cytokine storm can be seen in many other diseases, but most recently it has been demonstrated in the novel coronavirus disease 2019 (COVID-19).ConclusionHere we present a case of HGA in which diagnosis was delayed due to mimicry of COVID-19 infection. This case highlights the importance of taking clinical and social histories, seasonality and geography into account during diagnosis, and maintaining a broad differential with non-specific symptoms. Despite the current COVID-19 pandemic, we recommend that HGA remains in the differential diagnosis of a pro-inflammatory state with an atypical respiratory presentation.LEARNING POINTSHuman granulocytic anaplasmosis (HGA) has a widely variable clinical presentation and can be life-threatening.When presented with non-specific symptoms, it is critical to consider clinical and social histories, seasonality and geography while maintaining a broad differential.Cytokine storm can be seen in HGA and other diseases, but most recently it has been observed in the novel COVID-19. However, despite the prevalence of COVID-19, we recommend that HGA remain in the differential diagnosis of a pro-inflammatory state with an atypical respiratory presentation.

Molecular evidence of Anaplasma phagocytophilum in olive baboons and vervet monkeys in Kenya

BackgroundNonhuman primates (NHPs) play a significant role in zoonotic spill-overs, serving as either reservoirs, or amplifiers, of multiple neglected tropical diseases, including tick-borne infections. Anaplasma phagocytophilum are obligate intracellular bacteria of the family Anaplasmatacae, transmitted by Ixodid ticks and cause granulocytic anaplasmosis (formerly known as Human Granulocytic Ehrlichiosis (HGE)) in a wide range of wild and domestic mammals and humans too. The aim of this study was to determine whether Anaplasma phagocytophilum was circulating in olive baboons and vervet monkeys in Laikipia County, Kenya.ResultsSome 146 blood samples collected from olive baboons and 18 from vervet monkeys from Mpala Research Center and Ol jogi Conservancy in Laikipia County were screened for the presence of Anaplasma species using conventional Polymerase Chain Reaction (PCR), and then A. phagocytophilum was confirmed by sequencing using conventional PCR targeting 16S rRNA. This study found an overall prevalence of 18.3% for Anaplasma species. DNA sequences confirmed Anaplasma phagocytophilum in olive baboons for the first time in Kenya.ConclusionThis study provides valuable information on the endemicity of A. phagocytophilum bacteria in olive baboons in Kenya. Future research is needed to establish the prevalence and public health implications of zoonotic A. phagocytophilum isolates and the role of nonhuman primates as reservoirs in the region.

Current Status of the Natural Foci of Tick-Borne Diseases in the Stavropol Region

Background: Tick-borne diseases are a serious threat to the epidemiological safety of the population of the Stavropol Region, making up more than 70 per cent of all natural focal infectious diseases registered in this territory annually. A wide range of hosts contributes to high tick abundance, diversity of tick-borne pathogens, and maintenance of the natural foci. Objective: To assess the activity of natural foci of tick-borne infections in the Stavropol Region in 2016–2020. Materials and methods: We used notifications submitted by the Center for Hygiene and Epidemiology in the Stavropol Region to the Scientific and Methodological Center for Monitoring the Pathogens of Infectious and Parasitic Diseases of Pathogenicity Groups II–IV for the subjects of the North Caucasian and Southern Federal Districts and the results of an epizootological survey of the Stavropol territory by specialists of the Stavropol Plague Control Research Institute. Markers of the causative agents of tick-borne diseases were detected by ELISA and PCR methods. Data processing was carried out using Microsoft Excel 2010. Results: Active natural foci of Crimean-Congo hemorrhagic fever, Q fever, a group of tick-borne spotted fevers, Lyme disease, human granulocytic anaplasmosis, and human monocytic ehrlichiosis were established in the region in 2016–2020. Human cases of the Crimean-Congo hemorrhagic fever, Lyme borreliosis and Q fever were also registered annually. The abundance of infected ticks in resort towns of the Caucasian Mineral Waters is of particular concern. Conclusion: We established up-to-date epizootic and epidemic manifestations of tick-borne infections in the Stavropol Region in the modern period, which are an important link in epidemiological surveillance and the basis for improving preventive measures

Human granulocytic anaplasmosis combined with rhabdomyolysis: a case report

BackgroundHuman granulocytic anaplasmosis (HGA) is a systemic inflammatory response caused by the rickettsial bacterium Anaplasma phagocytophilum. Rhabdomyolysis and acute kidney injury (AKI) are rare complications of HGA. Here, we report a case of HGA concurrent with rhabdomyolysis and AKI in an elderly patient.Case presentationAn 84-year old woman with a medical history of hypertension was hospitalised after two days of fever, dizziness, whole body pain, and general weakness. Laboratory investigations showed severe thrombocytopenia, leukopenia, impaired renal function, and elevated cardiac enzyme and myoglobin levels. On the day after admission, peripheral blood smear revealed morula inclusions in neutrophils, a suggestive finding of HGA. Real-time polymerase chain reaction (PCR) results indicated the presence of A. phagocytophilum. Antibiotics were de-escalated to doxycycline monotherapy. After 10 days of antibiotic treatment, laboratory tests showed complete recovery from HGA complicated with rhabdomyolysis and AKI.ConclusionsHGA can lead to serious complications in patients with associated risk factors. Therefore, in patients with HGA accompanied by rhabdomyolysis, management with antibiotics and hydration should be initiated immediately, and not delayed until diagnostic confirmation.

EARLY IDENTIFICATION FOR PREVENTING SEVERE BABESIA PARASITEMIA AND ARDS IN A POST-SPLENECTOMY PATIENT

TOPIC: Chest Infections TYPE: Medical Student/Resident Case Reports INTRODUCTION: Babesiosis is an emerging health risk and a nationally notifiable disease in the United States.1 It can present as shock and multi-organ dysfunction in immunocompromised host. As babesiosis prophylaxis in patients with splenectomy is not common, it should be considered in post-splenectomy sepsis syndrome.1 This case describes a post-splenectomy patient with severe babesiosis presenting with refractory Acute Respiratory Distress Syndrome (ARDS). CASE PRESENTATION: 59-year-old man presented to emergency department with 2 weeks of worsening generalized weakness, fever, and headaches, not getting better on oral antibiotics prescribed outpatient. His Computed Tomography (CT) head, lumbar puncture was normal. He developed severe respiratory distress and was emergently intubated. Chest imaging revealed bilateral pulmonary infiltrates. Arterial blood gas analysis confirmed severe ARDS with a PaO2/FiO2 (P/F) ratio <100. The patient was managed with lung protective ventilation and prone positioning. Peripheral smear revealed intraerythrocytic ring inclusions consistent with Babesia microti trophozoites (Figure1). Testing for other bacterial infections, viral pathogens, and tick-borne illnesses were negative. Labs were significant for hemoglobin (Hb) 10.8 g/dl, platelet count 170 K/uL, haptoglobin <10 mg/dl, lactate dehydrogenase 373 U/L, aspartate aminotransferase 68 U/L and alanine aminotransferase 71 U/L. He was treated with atovaquone and azithromycin. Doxycycline was initiated for possible co-infection with other tick-borne illnesses. The patient also had red cell exchange transfusion given his critical condition and history of splenectomy. He was evaluated for Veno-venous extracorporeal membrane oxygenation (ECMO), but cannulation was deferred due to initial improvement with prone positioning. Though there was initial improvement, his hemodynamic status continued to decline requiring initiation of vasopressor support and was transitioned to comfort care after prolonged intubation with goals of care discussions with family. DISCUSSION: Early recognition and diagnosis of babesia, especially in patients with asplenia, is imperative as babesiosis can progress to refractory ARDS, shock and multi-organ dysfunction. Clinicians should have a high index of suspicion for a patient living in an endemic area who presents with unexplained nonspecific symptoms and laboratory findings including thrombocytopenia, hemolytic anemia, and/or elevation of liver enzymes. If clinical suspicion is high, sever real-time PCR assays are useful to detect low-grade parasitemia and are more sensitive than blood smears.2 Prone positioning has been shown to improve outcomes with ARDS if used early and for longer sessions and may help patients avoid need for ECMO.3 CONCLUSIONS: Our case reveals the importance of early recognition of babesiosis in immunocompromised patients living in endemic areas for preventing refractory ARDS. REFERENCE #1: Rosner F, Zarrabi MH, Benach JL, Habicht GS. Babesiosis in splenectomized adults: review of 22 reported cases. The American journal of medicine. 1984 Apr 1;76(4):696-701. REFERENCE #2: Sanchez E, Vannier E, Wormser GP, Hu LT. Diagnosis, treatment, and prevention of Lyme disease, human granulocytic anaplasmosis, and babesiosis: a review. Jama. 2016 Apr 26;315(16):1767-77. REFERENCE #3: Guérin C, Reignier J, Richard JC, Beuret P, Gacouin A, Boulain T, Mercier E, Badet M, Mercat A, Baudin O, Clavel M. Prone positioning in severe acute respiratory distress syndrome. New England Journal of Medicine. 2013 Jun 6;368(23):2159-68. DISCLOSURES: No relevant relationships by Kinjal Banerjee, source=Web Response No relevant relationships by Taesung Kwon, source=Web Response No relevant relationships by Thomas Lettich, source=Web Response No relevant relationships by Sanjeev Shrestha, source=Web Response No relevant relationships by Cynthia Tsai, source=Web Response

Ticks and their epidemiological role in Slovakia: from the past till present.

In Slovakia, 22 tick species have been found to occur to date. Among them, Ixodes ricinus, Dermacentor reticulatus, D. marginatus and marginally Haemaphysalis concinna, H. inermis and H. punctata have been identified as the species of public health relevance. Ticks in Slovakia were found to harbour and transmit zoonotic and/or potentially zoonotic agents such as tick-borne encephalitis virus (TBEV), spirochaetes of the Borrelia burgdorferi sensu lato (s.l.) complex, the relapsing fever sprirochaete Borrelia miyamotoi, bacteria belonging to the orders Rickettsiales (Rickettsia spp., Anaplasma phagocytophilum, Neoehrlichia mikurensis), Legionellales (Coxiella burnetii), and Thiotrichales (Francisella tularensis), and Babesia spp. parasites (order Piroplasmida). Ixodes ricinus is the principal vector of the largest variety of microorganisms including viruses, bacteria and piroplasms. TBEV, B. burgdorferi s.l., rickettsiae of the spotted fever group, C. burnetii and F. tularensis have been found to cause serious diseases in humans, whereas B. miyamotoi, A. phagocytophilum, N. mikurensis, Babesia microti, and B. venatorum pose lower or potential risk to humans. Distribution of TBEV has a focal character. During the last few decades, new tick-borne encephalitis (TBE) foci and their spread to new areas have been registered and TBE incidence rates have increased. Moreover, Slovakia reports the highest rates of alimentary TBE infections among the European countries. Lyme borreliosis (LB) spirochaetes are spread throughout the distribution range of I. ricinus. Incidence rates of LB have shown a slightly increasing trend since 2010. Only a few sporadic cases of human rickettsiosis, anaplasmosis and babesiosis have been confirmed thus far in Slovakia. The latest large outbreaks of Q fever and tularaemia were recorded in 1993 and 1967, respectively. Since then, a few human cases of Q fever have been reported almost each year. Changes in the epidemiological characteristics and clinical forms of tularaemia have been observed during the last few decades. Global changes and development of modern molecular tools led to the discovery and identification of emerging or new tick-borne microorganisms and symbionts with unknown zoonotic potential. In this review, we provide a historical overview of research on ticks and tick-borne pathogens in Slovakia with the most important milestones and recent findings, and outline future directions in the investigation of ticks as ectoparasites and vectors of zoonotic agents and in the study of tick-borne diseases.

Priority directions for non-specific prevention of tick-borne infections

Objective. An important role in the prevention of diseases, the causative agents of which are transmitted by ixodic ticks (tick-borne encephalitis, ixodic tick-borne borreliosis, human granulocytic anaplasmosis, human monocytic erlichiosis) is assigned to non-specific measures. To prevent infection by all pathogens of these infections at the same time, nonspecific preventive measures are of paramount importance. They include the extermination of hungry ticks on the vegetation of relatively small areas of natural biotopes, forest parks, health institutions, recreational areas, summer cottages or gardens; individual protection of the population from ticks and awareness-raising work.&#x0D; Materials and methods. The data of official statistics and materials of long-term observation of epidemic process were analyzed.&#x0D; Results. Despite the fact that since 2016 according to official data, there is observed a phase of decreased activity of the epidemic process of tick-borne infections, statistical analysis shows that in the forthcoming years an activation of epidemic situation is expected.&#x0D; Conclusions. In order to prevent tick attacks, specialists of medical organizations, departments of Rospotrebnadzor of the Russian Federation should intensify sanitary and educational work on non-specific protection of the population. In addition to standard activities, it is important to organize schools, courses for the public, schoolchildren, tourists and other population groups for the prevention of tick-borne infections, including the development of skills for correct tick removal using the Tick Removal Trainer and an algorithm for emergency measures in specific situation.

Ehrlichiosis and anaplasmosis subcommittee report to the Tick-borne Disease Working Group

Ehrlichioses and anaplasmosis have undergone dramatic increases in incidence, and the geographic ranges of their occurrence and vectors have also expanded. There is marked underreporting of these diseases owing to deficient physician awareness and knowledge of the illnesses as well as limited access to appropriate diagnostic tests. Human monocytic ehrlichiosis and anaplasmosis are life threatening diseases with estimated case fatality rates of 2.7 and 0.3%, respectively. However, knowledge of their full range of signs and symptoms is incomplete, and the incidence of subclinical infections is unknown. Currently available laboratory diagnostic methods are poorly utilized, and with the exception of nucleic acid amplification tests are not useful for diagnosis during the acute stage of illness when timely treatment is needed.The Ehrlichiosis and Anaplasmosis Subcommittee of the Tick-Borne Disease Working Group recommended active clinical surveillance to determine the true incidence, full clinical spectrum, and risk factors for severe illness, as well as standardized surveillance of ticks for these pathogens, and enhanced education of primary medical caregivers and the public regarding these diseases. The subcommittee identified the needs to develop sensitive, specific acute stage diagnostic tests for local clinical laboratories and point-of-care testing, to develop approaches for utilizing electronic medical records, data mining, and artificial intelligence for assisting early diagnosis and treatment, and to develop adjunctive therapies for severe disease.

COVID-19 and the Consequences of Anchoring Bias.

Suspicion of coronavirus disease in febrile patients might lead to anchoring bias, causing misdiagnosis of other infections for which epidemiologic risks are present. This bias has potentially severe consequences, illustrated by cases of human granulocytic anaplasmosis and Lyme disease in a pregnant woman and human granulocytic anaplasmosis in another person.

Epidemiology and Spatial Emergence of Anaplasmosis, New York, USA, 2010‒2018.

Human granulocytic anaplasmosis, a tickborne disease caused by the bacterium Anaplasma phagocytophilum, was first identified during 1994 and is now an emerging public health threat in the United States. New York state (NYS) has experienced a recent increase in the incidence of anaplasmosis. We analyzed human case surveillance and tick surveillance data collected by the NYS Department of Health for spatiotemporal patterns of disease emergence. We describe the epidemiology and growing incidence of anaplasmosis cases reported during 2010–2018. Spatial analysis showed an expanding hot spot of anaplasmosis in the Capital Region, where incidence increased >8-fold. The prevalence of A. phagocytophilum increased greatly within tick populations in the Capital Region over the same period, and entomologic risk factors were correlated with disease incidence at a local level. These results indicate that anaplasmosis is rapidly emerging in a geographically focused area of NYS, likely driven by localized changes in exposure risk.

Epidemiology and Spatial Emergence of Anaplasmosis, New York, USA, 2010‒2018

Abstract Human granulocytic anaplasmosis, a tickborne disease caused by the bacterium Anaplasma phagocytophilum, was first identified during 1994 and is now an emerging public health threat in the United States. New York state (NYS) has experienced a recent increase in the incidence of anaplasmosis. We analyzed human case surveillance and tick surveillance data collected by the NYS Department of Health for spatiotemporal patterns of disease emergence. We describe the epidemiology and growing incidence of anaplasmosis cases reported during 2010–2018. Spatial analysis showed an expanding hot spot of anaplasmosis in the Capital Region, where incidence increased >8-fold. The prevalence of A. phagocytophilum increased greatly within tick populations in the Capital Region over the same period, and entomologic risk factors were correlated with disease incidence at a local level. These results indicate that anaplasmosis is rapidly emerging in a geographically focused area of NYS, likely driven by localized changes in exposure risk.

A Comparative Spatial and Climate Analysis of Human Granulocytic Anaplasmosis and Human Babesiosis in New York State (2013-2018).

Human granulocytic anaplasmosis (HGA) and human babesiosis are tick-borne diseases spread by the blacklegged tick (Ixodes scapularis Say, Acari: Ixodidae) and are the result of infection with Anaplasma phagocytophilum and Babesia microti, respectively. In New York State (NYS), incidence rates of these diseases increased concordantly until around 2013, when rates of HGA began to increase more rapidly than human babesiosis, and the spatial extent of the diseases diverged. Surveillance data of tick-borne pathogens (2007 to 2018) and reported human cases of HGA (n = 4,297) and human babesiosis (n = 2,986) (2013-2018) from the New York State Department of Health (NYSDOH) showed a positive association between the presence/temporal emergence of each pathogen and rates of disease in surrounding areas. Incidence rates of HGA were higher than human babesiosis among White and non-Hispanic/non-Latino individuals, as well as all age and sex groups. Human babesiosis exhibited higher rates among non-White individuals. Climate, weather, and landscape data were used to build a spatially weighted zero-inflated negative binomial (ZINB) model to examine and compare associations between the environment and rates of HGA and human babesiosis. HGA and human babesiosis ZINB models indicated similar associations with forest cover, forest land cover change, and winter minimum temperature; and differing associations with elevation, urban land cover change, and winter precipitation. These results indicate that tick-borne disease ecology varies between pathogens spread by I. scapularis.

Modeling future climate suitability for the western blacklegged tick, Ixodes pacificus, in California with an emphasis on land access and ownership

In the western United States, Ixodes pacificus Cooley & Kohls (Acari: Ixodidae) is the primary vector of the agents causing Lyme disease and granulocytic anaplasmosis in humans. The geographic distribution of the tick is associated with climatic variables that include temperature, precipitation, and humidity, and biotic factors such as the spatial distribution of its primary vertebrate hosts. Here, we explore (1) how climate change may alter the geographic distribution of I. pacificus in California, USA, during the 21st century, and (2) the spatial overlap among predicted changes in tick habitat suitability, land access, and ownership. Maps of potential future suitability for I. pacificus were generated by applying climate-based species distribution models to a multi-model ensemble of climate change projections for the Representative Concentration Pathway (RCP) 4.5 (moderate emission) and 8.5 (high emission) scenarios for two future periods: mid-century (2026-2045) and end-of-century (2086-2099). Areas climatically-suitable for I. pacificus are projected to expand by 23% (mid-century RCP 4.5) to 86% (end-of-century RCP 8.5) across California, compared to the historical period (1980-2014), with future estimates of total suitable land area ranging from about 88 to 133 thousand km2, or up to about a third of California. Regions projected to have the largest area increases in suitability by end-of-century are in northwestern California and the south central and southern coastal ranges. Over a third of the future suitable habitat is on lands currently designated as open access (i.e. publicly available), and by 2100, the amount of these lands that are suitable habitat for I. pacificus is projected to more than double under the most extreme emissions scenario (from ~23,000 to >51,000 km2). Of this area, most is federally-owned (>45,000 km2). By the end of the century, 26% of all federal land in the state is predicted to be suitable habitat for I. pacificus. The resulting maps may facilitate regional planning and preparedness by informing public health and vector control decision-makers.

Clinical and laboratory evidence of Lyme disease in North India, 2016–2019

BackgroundLyme disease is endemic to parts of the Americas, Europe and Asia. However, only a handful of sporadic cases have been reported from India. In this study, we systematically evaluated the clinical and epidemiological features of Lyme disease in North India. MethodAll samples were tested by using the standard two-tiered testing algorithm (STTA). Paired serum and cerebrospinal fluid (CSF) were used for demonstrating Borrelia burgdorferi specific intrathecal IgG antibody synthesis (AI). In addition, a commercial tick-borne bacterial flow chip (TBFC) system and a real-time PCR were also used to detect Borrelia species and Anaplasma phagocytophilum in patients who were positive by STTA. ResultsThe diagnosis of Lyme disease was confirmed in 18 (7.14%) of the 252 clinically suspected cases by STTA. Neurological involvement was reported in 14 (77.78%) patients, whereas joint and heart involvement was reported in five (27.78%) and three (16.67%) patients, respectively. Lymphocytic pleocytosis (median 37.5 cells/mm3; range 12–175 cells/mm3) in the CSF was seen in 11 of 14 Lyme neuroborreliosis (LNB) patients. Intrathecal production of Borrelia specific IgG antibodies was demonstrated in 9 (64.28%, n = 14) patients, a highly specific finding for neuroborreliosis. Two patients (11.11%) were also found to be co-infected with human granulocytic anaplasmosis. ConclusionsThe results of this study show clinical and laboratory evidence of endemic Lyme disease in North India and thus, highlight the importance for travel medicine practitioners and physicians to evaluate for Lyme disease in patients with compatible symptoms and a history of travel to tick risk areas.

Anaplasma phagocytophilum AptA enhances the UPS, autophagy, and anti-apoptosis of host cells by PSMG3

Anaplasma phagocytophilum is an obligate intracellular bacterium and a common tick-borne infectious pathogen that can cause human granulocytic anaplasmosis (HGA). Effector proteins play an important role in the pathogenic mechanism of A. phagocytophilum, but the specifics of the disease mechanism are unclear. We studied the effector protein AptA (A. phagocytophilum toxin A) using yeast two hybrid assays to screen its interacting protein proteasome assembly chaperone 3 (PSMG3, PAC3), and identified new mechanisms for the pathogenicity of A. phagocytophilum in HEK293T cells. After AptA enters the host cell, it interacts with PSMG3 to enhance the activity of the proteasome, causing ubiquitination and autophagy in the host cell and thereby increasing cross-talk between the ubiquitination-proteasome system (UPS) and autophagy. AptA also reduces the apoptotic efficiency of the host cells. These results offer new clues as to the pathogenic mechanism of A. phagocytophilum and support the hypothesis that AptA interacts with host PSMG3.

Anaplasma phagocytophilum in domestic cats from Germany, Austria and Switzerland and clinical/laboratory findings in 18 PCR-positive cats (2008-2020).

Anaplasma phagocytophilum is considered the most significant rickettsial pathogen affecting cats. The organism is transmitted by ticks of the species Ixodes ricinus in Central Europe and can cause granulocytic anaplasmosis in pets, wildlife and humans. The aims of this study were to assess the frequency of positive test results for A phagocytophilum in cats in Germany, Austria and Switzerland, as well as to evaluate clinical and laboratory findings in cats with positive PCR results. This study included the results of direct (PCR) and indirect detection methods (immunofluorescence antibody tests [IFAT]) requested by veterinarians in Germany, Austria and Switzerland between 2008 and 2020 from the LABOKLIN laboratory (Bad Kissingen, Germany). The veterinarians treating the PCR-positive cats were contacted by telephone to enquire about their clinical signs, laboratory findings, management and outcomes. In total, 244/1636 cats (15%) tested positive by direct (PCR: n = 27/725 [4%]) and/or indirect detection methods (IFAT: n = 221/956 [23%]). In 18/26 cats with PCR results positive for A phagocytophilum, additional information about clinical signs, laboratory findings, treatment and outcome was obtained. Of these 18 cats, five had comorbidities independent of their infection with A phagocytophilum. The most common clinical signs in PCR-positive cats (total/without comorbidities) were lethargy (83%/92%), fever (83%/85%) and thrombocytopenia (61%/62%). Overall, more than half (57%) of the cats with and without comorbidities recovered clinically. Infections with A phagocytophilum should be considered as differential diagnoses in cats with tick infestation, lethargy, fever and thrombocytopenia. The clinical signs and laboratory findings are consistent with published case reports in cats. Ectoparasite prophylaxis in cats is recommended throughout the entire year.