Tick-borne infections and co-infections in patients with non-specific symptoms in Poland

Aim

The aim of the study was the evaluation of the frequency of infections and co-infections among patients hospitalized because of non-specific symptoms after a tick bite.

Assessment of tick-borne pathogens presence in Dermacentor reticulatus ticks in north-eastern Poland

PurposeDermacentor reticulatus is the second most common tick species in Poland after Ixodes ricinus. The aim of the study was to analyze the presence of pathogen DNA in D. reticulatus.Materials and methodsTicks were collected in The Protected Landscape Area of the Bug and Nurzec Valley (52°40′ N and 22°28’ E) between 2016 and 2017. End-point PCR for Borrelia burgdorferi sensu lato, Anaplasma phagocytophilum, Babesia spp., Rickettsia spp., Bartonella spp. and Coxiella burnetii detection was performed.ResultsTick-borne pathogens’ DNA was detected in 11.3% of 301 ticks: B. burgdorferi s.l. in 3.6%, Babesia spp. in 6.3%, A. phagocytophilum in 0.7% and B. burgdorferi s.l.-Babesia spp. co-infection in 0.7%. In all 21 Babesia spp. positive samples, sequence analysis confirmed the presence of Babesia canis with an 80.3%–98.3% homology with the B. canis sequences in GenBank. C. burnetii, Bartonella spp., and Rickettsia spp. DNA were not detected.ConclusionsDermacentor reticulatus from north-eastern Poland were found to carry three of the most common tick-borne pathogens (B. burgdorferi s.l., Babesia canis, A. phagocytophilum) which lead to single and mixed infections. Babesia canis was the most prevalent pathogen identified in D. reticulatus.     

Serological detection of Anaplasma phagocytophilum,Borrelia burgdorferi sensu lato and Ehrlichia canis antibodies and Dirofilaria immitis antigen in a countrywide survey in dogs in Poland

Canine vector-borne diseases (CVBDs) have increasingly become a focus of attention in the past few years. Nevertheless, in many parts of Europe information on their occurrence is still scarce. In a large study in Poland 3,094 serum samples taken from dogs throughout all 16 Polish provinces were tested using a commercial kit for the detection of circulating antibodies against Anaplasma phagocytophilum, Borrelia burgdorferi sensu lato and Ehrlichia canis and of Dirofilaria immitis antigen. A total of 12.31 % (381/3,094; 95 % confidence interval [CI]: 11.18–13.52 %) and 3.75 % (116/3,094; 95 % CI: 3.11–4.48 %) of the dogs were positive for A. phagocytophilum and B. burgdorferi s.l. antibodies, respectively. Furthermore, 0.26 % (8/3,094; 95 % CI: 0.11–0.51 %) were positive for E. canis antibodies and 0.16 % (5/3,094; 95 % CI: 0.05–0.38 %) for D. immitis antigen. The highest percentages of A. phagocytophilum-positive dogs were noted in Lesser Poland, Silesia and ?ód? Provinces. For B. burgdorferi s.l., the highest prevalence was recorded in ?ód? Province. Co-infections with A. phagocytophilum and B. burgdorferi s.l. were recorded in 1.71 % of all examined dogs (53/3,094; 95 % CI: 1.29–2.23 %). One dog even had a triple infection, testing positive for E. canis too. Both A. phagocytophilum and B. burgdorferi s.l. have previously been reported in Poland and were confirmed in the present study by positive samples from all 16 provinces. Concerning E. canis and D. immitis travel history or importation cannot be excluded as factors which may have determined the occurrence of these pathogens in the relevant animals. Practitioners in Poland should be aware of the above mentioned CVBDs and of prophylactic measures to protect dogs and their owners.     

Assessment of PCR status of vector-borne pathogens in dogs presenting arrhythmias

Arrhythmias are frequent and can be caused by many diseases. Vector-borne diseases are increasing in importance as a cause of arrhythmias in veterinary medicine. The objective of the study was to evaluate dogs presenting arrhythmias of any aetiology and to assess the influence of polymerase chain reaction (PCR) status for vector-borne pathogens in the Mediterranean area of Spain. A total of 120 dogs presenting arrhythmias were prospectively selected, and PCR for several vector-borne pathogens (Leishmania infantum, Ehrlichia/Anaplasma spp., Babesia spp., Rickettsia spp., Mycoplasma spp., Hepatozoon canis and Bartonella spp.) were analysed in blood samples. Twenty-four (20 %) dogs had positive results for PCR. Found pathogens were Ehrlichia/Anaplasma spp. (n?=?10, 8.3 %), Babesia spp. (n?=?7, 5.8 %), Rickettsia spp. (n?=?5, 4.2 %), Leishmania spp. (n?=?4, 3.3 %), Mycoplasma spp. (n?=?4, 3.3 %), and H. canis (n?=?1, 0.8 %). No significant differences were found in relation to PCR status and type or cause of the arrhythmia. Although there is a clear association between some infectious diseases and cardiac diseases, this study could not find evidence of the role of infectious agents as triggers for arrhythmias in dogs. More studies are needed to further explore this association.     

Prevalence of Rickettsiales (Anaplasma phagocytophilum and Rickettsia spp.) in hard ticks (Ixodes ricinus) in the city of Hamburg,Germany

To narrow the gap of missing knowledge on Rickettsia spp. and Anaplasma phagocytophilum infections in ticks in northwestern Germany and, at the same time, to provide first prevalence data on these pathogens in the city of Hamburg, a total of 1,400 questing Ixodes ricinus ticks were collected at ten different public green areas from April until October 2011. Ticks were examined using probe-based quantitative real-time PCR. A percentage of 3.6 % (51/1,400) ticks were tested positive for A. phagocytophilum infections divided into 2.1 % (3/141) adults [1.7 % (1/60) females and 2.5 % (2/81) males] and 3.8 % (48/1,259) nymphs. The percentage of infected ticks per sampling site varied statistically significantly from 0.7 % (1/140) to 12.1 % (17/140), whereas between sampling months, no statistically significant differences were observed (2.0–6.5 %, 4–13/140). The overall Rickettsia spp. infection rate was 52.5 % (735/1,400). In adult ticks, Rickettsia spp. infection rate was 56 % (79/141) divided into 61.7 % (37/60) infected females and 51.9 % (42/81) infected males. Nymphs showed an infection rate of 52.1 % (656/1,259). In contrast to A. phagocytophilum infections, no statistically significant differences in Rickettsia spp. infection rates among sampling sites (44.3–63.6 %, 62–89/140) were observed, whereas seasonal variations were obvious: the percentage of Rickettsia-positive ticks was significantly lower in April (36.5 %, 73/200) and May (29.5 %, 59/200) compared to the summer and fall months (55.0–64.5 %, 110–129/200). Rickettsia species differentiation via real-time pyrosequencing revealed Rickettsia helvetica as the only occurring species. Co-infections with both Rickettsia spp. and A. phagocytophilum were detected in 2.0 % (28/1,400) of the ticks. The present study revealed that in the city of Hamburg, the tick infection rate with A. phagocytophilum is comparable with other German data, whereas the Rickettsia spp. infection rate of 52.5 % is by far the highest prevalence detected in Germany so far. As the city of Hamburg has 1.8 million inhabitants and attracts millions of tourists every year, the potential health risk should not be underestimated.     

Genetic polymorphism of CCL2-2510 and susceptibility to enterovirus 71 encephalitis in a Chinese population

The study was performed in 36 Chinese patients with enterovirus 71 (EV71) encephalitis and 141 patients with EV71-related hand, foot and mouth disease (HFMD) without encephalitis. Genotyping was done by the polymerase chain reaction-restriction fragment length polymorphism technique. Patients with EV71 encephalitis had a significantly higher frequency of the CCL2-2510GG genotypes when compared to patients with EV71-related HFMD without encephalitis (66.7 % vs. 41.8 %, p = 0.028). The frequency of CCL2-2510G alleles was also significantly higher among the patients with EV71 encephalitis than among patients with EV71-related HFMD without encephalitis (79.2 % vs. 64.9 %, OR = 2.1, 95 % CI = 1.1-3.8, P = 0.023). Significant differences were found in gender, age, fever days, white blood cell count, C-reactive protein level, blood glucose concentration, and CCL2 level among genotypes of CCL2-2510A/G in EV71-infected patients, but no significant differences were found in alanine aminotransferase, aspartate aminotransferase, or creatine kinase myocardial isozyme levels or in cerebrospinal fluid evaluations (except monocytes) in patients with EV71 encephalitis. These findings suggest that the CCL2-2510G allele is associated with susceptibility to EV71 encephalitis in Chinese patients.     

Longitudinal field study on bovine Babesia spp. and Anaplasma phagocytophilum infections during a grazing season in Belgium

Anaplasmosis and babesiosis are major tick-borne diseases with a high economic impact but are also a public health concern. Blood samples collected in the spring, summer, and autumn of 2010 from 65 cows in seven different farms in Belgium were monitored with an indirect immunofluorescence antibody test to assess seroprevalence against these pathogens. Seroprevalences to Babesia spp. were measured as 10.7%, 20%, and 12.3% in spring, summer, and autumn, respectively, whereas seroprevalences to Anaplasma phagocytophilum were 30.8%, 77%, and 56.9%, respectively. A total of 805 Ixodes ricinus ticks were collected at the same time from both cattle (feeding ticks) and grazed pastures (questing ticks). The infection level of ticks, assessed by PCR assay, for Babesia spp. DNA was 14.6% and 7.9% in feeding and questing ticks, respectively, whereas 21.7% and 3% of feeding and questing ticks were found be positive for A. phagocytophilum cDNA. Fifty-five PCR-positive samples were identified by sequencing as Babesia sp. EU1, of which five from feeding ticks were positive for both A. phagocytophilum and Babesia sp. EU1. The high density of wild cervids in the study area could explain these observations, as deer are considered to be the main hosts for adults of I. ricinus. However, the absence of Babesia divergens both in feeding and questing ticks is surprising, as the study area is known to be endemic for cattle babesiosis. Increasing cervid populations and comorbidity could play an import role in the epidemiology of these tick-borne diseases.     

Peripheral facial palsy in patients with tick-borne encephalitis

Although tick-borne encephalitis (TBE) has been recognized in Europe for more than 70 years and has been the topic of numerous reports, information on the involvement of facial nerves in the course of the disease is limited. Our study conducted at a single medical centre revealed that facial nerve involvement in the course of TBE in Central Europe is (i) infrequent—it was found in only 11 of 1218 (0.9%) consecutive adult patients diagnosed with TBE; (ii) manifests with unilateral or rarely bilateral peripheral facial palsy (PFP) (nine and two patients, respectively); (iii) appears late in the course of acute illness—in our patients 10-20 days after the onset of the meningoencephalitic phase of TBE, and often after defervescence (in 8/11 patients; 6-13 days after normalization of body temperature); (iv) develops more often in patients with more severe illness, i.e. more frequently in those with encephalitic than in those with meningitic clinical presentation, and more commonly in patients with monophasic than biphasic illness; and (v) has a favourable outcome—our patients had a clinically complete recovery from PFP within 7-90 (median 30) days after its onset. Moreover, the finding of Borrelia infection in 3/11 (27.3%) patients (diagnosis of confirmed Lyme neuroborreliosis was established in 1/11 patients and two patients fulfilled criteria for possible Lyme neuroborreliosis) suggests that in countries where TBE and Lyme borreliosis are endemic, concomitant infection with Borrelia burgdorferi sensu lato should be considered and searched for in patients who develop PFP in the course of TBE.     

Foci of tick-borne diseases in Southwest Germany

Presently known tick-borne diseases in Germany include Lyme borreliosis, tick-borne encephalitis (TBE-virus, western subtype), Q-fever, babesiosis and presumably ehrlichiosis. Blood samples of 4,368 forestry workers in the State of Baden-Wuerttemberg (B-W), southwestern Germany, were tested for the presence of antibodies against Borrelia burgdorferi sensu lato, TBE-virus and Ehrlichia spp. (genogroup E. phagocytophila). Furthermore 12,327 ticks (Ixodes ricinus) collected in various areas of B-W were analysed by PCR and genotyping for the prevalence of pathogen RNA and DNA. The human seroprevalence rates of antibodies to B. burgdorferi sensu lato ranged from 18 % to 52 %, for TBE-virus from 0 % to 43 % and for Ehrlichia spp. from 5 % to 16 % in various counties of the State. The foci of B. burgdorferi and TBE-virus as indicated by antibody prevalence in humans are only partly overlapping with each other. The highest rates of TBE-virus antibodies are in concordance with available clinical data. However antibody prevalence up to 27 % in areas with no reports of clinical cases was found, suggesting that TBE occurs throughout the State of B-W, The prevalence of Ehrlichia spp. antibodies suggests that ehrlichiosis plays a role as a tick-borne disease in Germany, but as long as no clinical data are available, this will remain unclear.Investigations of ticks for TBE-virus (n = 9,189) by nested PCR showed prevalence rates from 0% to 2.3% and for Ehrlichia spp. (n = 1,963) from 2.6% to 3.1%. Examination of ticks (n = 3,138) for the presence of B. burgdorferi sensu lato DNA was performed by PCR and revealed prevalence rates from 13.9% up to 24%. Furthermore 1,106 samples positive for B. burgdorferi sensu lato were used for genotyping. B. afzelii DNA was found in 407 ticks (36.8%), followed by B. garinii (21.9 %), B. valaisiana (13.7%), and B. burgdorferi sensu stricto (9.9 %). Double infection was found in 6.4% and triple infection in 0.8% of the ticks. 10.5% of the positive samples could not be classified.Prevention of tick-borne diseases has to focus on behavioural intervention to reduce individual tick exposure by proper behaviour in the environment, as a large-scale control of the tick population seems impossible and thus reduction of Lyme borreliosis and TBE through tick control is unlikely. Vaccination against TBE-virus should not only be recommended for high endemic areas but also for persons with a high individual risk.     

Relationship of faecal egg count with packed cell volume and anaemia in Sahel sheep and goats in semi-arid northeastern Nigeria

Sahel sheep and goats, under extensive or semi-intensive management in smallholder farms in semi-arid northeastern Nigeria (Maiduguri), were evaluated to determine the relationship between faecal egg count (FEC) and packed cell volume (PCV) with associated anaemia and whether concurrent haemoparasitic infections would confound the variables. Faecal and anticoagulated blood samples from Sahel sheep (n?=?227) and goats (n?=?415) were collected January–December 2006, after conjunctival colour was estimated as FAMACHA score (FS) as follows: red (1), red–pink (2), pink (3), pink–white (4) or white (5). Presumed level of helminth infection, based on FEC with modified McMaster technique, was graded as mild (<600/g), moderate (600–1,500/g) or severe (>1,500/g). Out of 642 animals, 276 (43.0 %) had helminth infection based on FEC. More goats (11.5 %) were severely infected than sheep (1.3 %). PCV was decreased by only severe helminth burden. FS correlated with PCV (r?=??0.69, ?0.86; p?Babesia, 0.8 %; Anaplasma, 5.6 %) was observed in 16 (2.5 %) animals and did not have confounding effects on FEC and PCV. This report has provided preliminary information needed for further evaluation of the diagnostic criteria for helminthiasis and the associated anaemia in a semi-arid environment.     

Prevalence and incidence of antibodies to Borrelia burgdorferi and to tick-borne encephalitis virus in agricultural and forestry workers from Tuscany, Italy

The ticks Ixodes persulcatus and Ixodes ricinus are the main vectors of both Borrelia burgdorferi sensu lato and tick-borne encephalitis (TBE) virus in Eurasia. Borrelia burgdorferi is the cause of Lyme borreliosis, and TBE is a biphasic meningoencephalitis induced by an arbovirus belonging to the flavivirus family. The principal aims of the current investigation were (i) to determine the frequency of serological evidence of Borrelia burgdorferi sensu lato and TBE infections in healthy agricultural and forestry workers, (ii) to determine the incidence of seroconversion for antibodies against Borrelia burgdorferi sensu lato and TBE virus in Tuscan workers during a 1-year survey; and (iii) to assess the occupational risk for agricultural and forestry activities in a defined area (Tuscany, Italy). A total of 412 blood samples were taken from agricultural and forestry workers, and information on age, duration of employment, and history of tick bites was collected in a questionnaire to establish the risk factors for the diseases. Three hundred sixty-five blood donors from the same region served as controls. To estimate the rate of seroconversion, 176 of the agricultural and forestry workers were tested 1 year later. IgG and IgM antibodies against Borrelia burgdorferi sensu lato and TBE virus were detected in serum by an enzyme-linked immunosorbent assay and confirmed by Western blot analysis for Borrelia burgdorferi and by a test for inhibition of hemagglutination for TBE. Antibodies against Borrelia burgdorferi were more frequent among the workers than in the control group (7.8% vs. 4.9% in the IgG-IgM enzyme-linked immunosorbent assay and 7.03% vs. 3.56% in the confirmatory test). No seropositivity was observed for TBE virus. Eighteen of 176 subjects who underwent a second blood test developed specific antibodies against Borrelia burgdorferi within 1 year.     

Characterisation of ecto- and endoparasites in domestic cats from Tirana,Albania

During 2008 to 2011, faecal samples, ear swabs, and ectoparasites obtained by full body search and total body comb were collected from 252 cats originating from the greater Tirana area. Faecal samples were examined using the McMaster and Baermann techniques, and a subset of 58 samples was tested for Giardia-specific antigen using a coproantigen enzyme-linked immunosorbent assay (ELISA). The ear swabs were examined for the presence of parasitic mites. Overall, almost 93 % of the cats were identified harbouring one or more parasites: 59.1 % (95 % confidence interval (CI), 53.0–65.0) and 86.9 % (95 % CI, 82.7–91.1) of the cats tested positive for ecto- or endoparasites, respectively; 53.2 % of the cats had evidence for concomitant ectoparasite infestation and endoparasite infection. For ectoparasite infestation, prevalence was 52.0 % for total fleas (Ctenocephalides felis, 51.2 %; Ctenocephalides canis, 2.0 %; and Leptopsylla segnis, 0.4 %), 8.3 % each for Felicola subrostratus and Otodectes cynotis and 4.0 % for Rhipicephalus sanguineus sensu lato. The most prevalent endoparasites were Toxocara ascarids (48.0 %), followed by Aelurostrongylus lungworms (39.7 %), Capillaria spp. (31.7 %), hookworms (32.9 %), dipylidiid cestodes (27.8 %), Cystoisospora spp. (23.4 %) and taeniid cestodes (2.0 %). One animal was found shedding Pseudamphistomum truncatum eggs. Giardia-specific antigen was detected in 29.3 % of the 58 cats tested. Mixed infections with up to six endoparasites concurrently (excluding Giardia) and mixed infestations with two or three species of ectoparasites were recorded in 73.1 and 22.8 % of the parasite-positive cats, respectively. Cats ≤9 months of age were more frequently tested (p?Toxocara and Cystoisospora infections than cats >9 months while these cats tested more often (p?Aelurostrongylus-positive compared with the younger cats. The prevalence of infestation with ectoparasites did not differ between the cats of these two age groups. Given the impact that some of the parasites may have upon animal health as well as the zoonotic potential of some of them, measures should be taken to minimise the transmission of these parasites.     

Molecular identification of Theileria and Babesia in sheep and goats in the Black Sea Region in Turkey

This study was carried out to investigate presence and distribution of Theileria and Babesia species via microscopic examination and reverse line blotting (RLB) techniques in sheep and goats in the Black Sea region of Turkey. For this purpose, 1,128 blood samples (869 sheep and 259 goats) were collected by active surveillance from sheep and goats in different provinces of various cities in the region in the years 2010 and 2011. Smears were prepared from the blood samples, stained with Giemsa, and examined under the light microscope for Theileria and Babesia piroplasms. The genomic DNAs were extracted from blood samples. The length of 360–430-bp fragment in the variable V4 region of 18S SSU rRNA gene of Theileria and Babesia species was amplified using the gDNAs. The polymerase chain reaction products were hybridized to the membrane-connected species-specific probes. A total of 38 animals (3.37 %) including 34 sheep (3.91 %) and 4 goats (1.54 %) were found to be positive for Theileria spp. piroplasms in microscopic examination of smears while Babesia spp. piroplasm could not detected. Infection rates were 34.64 % in sheep, 10.04 % in goats, and totally 28.99 % for Theileria ovis while 0.58 % in sheep and totally 0.44 % for Babesia ovis. However, Theileria sp. OT3 was detected in 2.65 % of sheep and 2.04 % of all animals; besides Theileria sp., MK had 0.58 % prevalence in sheep and 0.77 % in goats, with a total 0.62 % with RLB. Although T. ovis and Theileria sp. MK were determined in both sheep and goats, B. ovis and Theileria sp. OT3 were observed only in the sheep. These results provide the first detailed molecular data for sheep and goat theileriosis and babesiosis in the region.     

Humoral Immune Responses in Patients with Lyme Neuroborreliosis

The aim of this study was to analyze and compare the humoral immune responses in serum and cerebrospinal fluid (CSF) for 34 adult patients with clinically evident Lyme neuroborreliosis, 27 patients with clinically suspected Lyme neuroborreliosis, and 32 patients with tick-borne encephalitis. Additionally, we wanted to compare the findings of two methods for the detection of intrathecally synthesized borrelial antibodies: the IDEIA Lyme neuroborreliosis test using flagellar antigen and an approach based on the Liaison indirect chemiluminescence immunoassay using the OspC and VlsE antigens. Borrelial IgM and IgG antibodies were detected by at least one of these methods in the sera of 22/34 (64.7%) and 28/34 (82.4%) patients with clinically evident Lyme neuroborreliosis, respectively, and in the cerebrospinal fluid of 22/34 (64.7%) and 20/34 (58.8%) of these patients, respectively. Intrathecal synthesis of borrelial IgM and/or IgG was found in 19/34 (55.9%) patients: IgM in 17/34 (50%) patients and IgG in 15/34 (44.1%) patients. The relatively low proportion of intrathecal synthesis of borrelial antibodies and the high ratio of IgM positivity could be explained by the short duration of neurological disease as evidenced by reported symptoms (median, 10 days). Assessment of the humoral immune response in the sera and CSF of patients with early Lyme neuroborreliosis confirmed previous findings on the relationship between the duration of illness and the proportion of patients with detectable responses.Lyme borreliosis is a multisystemic disease caused by the tick-transmitted spirochete Borrelia burgdorferi sensu lato. In the course of the disease, many different organs and organ systems may be affected, including the nervous system (Lyme neuroborreliosis) (20). In Europe, Borrelia garinii is the main cause of Lyme neuroborreliosis, whereas Borrelia afzelii is mostly associated with skin manifestations (17, 20).Diagnosis of Lyme neuroborreliosis is usually based on isolation of B. burgdorferi sensu lato from cerebrospinal fluid (CSF), demonstration of borrelial DNA in CSF samples, and/or detection of specific borrelial antibodies (seroconversion and/or intrathecal production). Isolation of the etiological agent from CSF still represents the gold standard, although the method is demanding, time-consuming, and of low sensitivity (1, 4, 20). Detection of intrathecal synthesis of specific antibodies, a conventional diagnostic marker of Lyme neuroborreliosis (3), is convenient for routine laboratory work but has limitations in that the antibodies may be absent during the first few weeks (10), and a positive test result does not distinguish between acute infection and past infection (8).The aim of this study was to assess the humoral immune responses in the sera and CSF of patients with Lyme neuroborreliosis and to compare the findings of two methods for the detection of intrathecally synthesized borrelial antibodies. We expected (i) that the proportions of patients with borrelial antibodies in serum would be similar in cases of clinically evident and clinically suspected Lyme neuroborreliosis and would be higher than those for patients with tick-borne encephalitis (TBE); (ii) that patients with clinically evident Lyme neuroborreliosis would have borrelial antibodies in CSF more often than those with suspected Lyme neuroborreliosis, and that these antibodies would be found only exceptionally in the CSF of patients with TBE; and (iii) that intrathecal borrelial antibody production would be limited to patients with clinically evident Lyme neuroborreliosis, with potential rare exceptions for patients with suspected Lyme neuroborreliosis.     

Application of TaqMan qPCR for the detection and monitoring of Naegleria species in reservoirs used as a source for drinking water

Naegleria spp. can be found in the natural aquatic environments. Naegleria fowleri can cause fatal infections in the central nervous system in humans and animals, and the most important source of infection is through direct water contact. In this study, PCR of 5.8S ribosomal RNA (rRNA) gene and internal transcribed spacer (ITS) region was performed in order to identify Naegleria isolates and quantify the Naegleria spp. by TaqMan real-time quantitative PCR in reservoir water samples. The occurrence of Naegleria spp. was investigated in 57 water samples from reservoirs with culture and PCR positive in 2 of them (3.5 %), respectively. The total detection rate was 7.0 % (4/ 57) for Naegleria spp. The identified species included Naegleria spp., Naegleria canariensis, and Naegleria clarki. N. fowleri was not found in Taiwan’s reservoirs used for drinking purposes. The concentrations of Naegleria spp. in detected positive reservoir water samples were in the range of 599 and 3.1?×?10³ cells/L. The presence or absence of Naegleria spp. within the reservoir water samples showed significant difference with the levels of water temperature. The presence of Naegleria spp. in reservoirs considered a potential public health threat if pathogenic species exist in reservoirs.     

Distribution of common pathogens in patients with pyogenic liver abscess in China: a meta-analysis

Pyogenic liver abscess (PLA) is a potentially life-threatening disease in many parts of the world, especially in Asia. The aim of this study was to quantify the proportion of common pathogens in patients with PLA in China, using a meta-analysis method based on systematic review of published studies. Several electronic databases were searched to identify the studies reporting the pathogens of PLA. We performed a meta-analysis to calculate the pooled proportion of pathogens and subgroup analysis among the included studies using R 3.1.1 software. In total, 183 studies were included in our final analysis, Klebsiella spp (54 %), Escherichia spp (29 %), Enterobacter spp (9 %), Proteus spp (6 %) and Pseudomonas spp (5 %) comprised the major gram-negative bacteria. Gram-positive bacteria mainly included Staphylococcus spp (13 %), Streptococcus spp (8 %) and Enterococcus spp (7 %). The distribution of pathogens in PLA patients were different in different economic regions in China. The proportion of Klebsiella spp had an upward tendency in recent years compared to other pathogens. In addition, the proportion of common pathogens in PLA patients with diabetes mellitus (DM) were carried out indicating that the dominant pathogens were Klebsiella spp (66 %), Escherichia spp (21 %) and Enterobacter spp (11 %). This meta-analysis showed that the main pathogens of PLA were Klebsiella spp, Escherichia spp, Staphylococcus spp, and Enterobacter spp in China. To ensure a precise estimate of the epidemiology of the pathogens, further large-scale or even a population-based study is needed.     

PCR-detection and molecular-genetic analysis of tick-transmitted pathogens in patients of Novosibirsk region,Russia

Blood samples of patients collected after tick bite in Novosibirsk region, Russia, in spring–summer of 2003–2004 were examined for tick-borne encephalitis virus (TBEV), Borrelia, Anaplasma, Babesia, and Rickettsia by (RT)-PCR. TBEV of the Far-Eastern subtype, Bo. garinii, Bo. afzelii, and Rickettsia sp. closely related to R. sibirica but not Anaplasma sp. or Babesia sp. were found.     

Risk of acquiring tick-borne infections in forestry workers from Lazio, Italy

The seroprevalence of antibodies to Borrelia burgdorferi and tick-borne encephalitis (TBE) virus was evaluated in a group of forestry rangers in the Lazio region of Italy. One hundred and forty-five forestry rangers and 282 blood donors were examined by two-tiered serological tests for B. burgdorferi and TBE virus. Information on occupation, residence, tick bites, outdoor leisure activities and other risk factors was obtained. The prevalence of IgG/IgM antibodies to B. burgdorferi showed no statistical difference between the two groups, but there was a higher occurrence of IgM antibodies. There were significant differences between indoor and outdoor, urban and rural workplaces among the 145 exposed workers (χ² test: p?<?0.001), and a higher risk for outdoor rural than urban tasks was detected among the ten Western blot-tested forestry rangers positive to B. burgdorferi (χ² test: p?<?0.1). No seropositivity was observed for the TBE virus. Forestry rangers from the Lazio region did not have a higher risk of Borrelia infection than the blood donors, though an increase in the risk for outdoor tasks in a rural environment was observed.     

Serological reactivity to <Emphasis Type="Italic">Anaplasma phagocytophilum</Emphasis> in neoehrlichiosis patients

The tick-borne bacterium Candidatus (Ca.) Neoehrlichia (N.) mikurensis is a cause of “fever of unknown origin” because this strict intracellular pathogen escapes detection by routine blood cultures. Case reports suggest that neoehrlichiosis patients may display serological reactivity to Anaplasma (A.) phagocytophilum. Since Anaplasma serology is part of the diagnostic work-up of undetermined fever in European tick-exposed patients, we wanted to investigate (1) the prevalence of A. phagocytophilum seropositivity among neoehrlichiosis patients, (2) the frequency of misdiagnosed neoehrlichiosis patients among A. phagocytophilum seropositive patients, and (3) the frequency of A. phagocytophilum and Ca. N. mikurensis co-infections. Neoehrlichiosis patients (n?=?18) were analyzed for A. phagocytophilum IgM and IgG serum antibodies by indirect immunofluorescence assay. Serum samples from suspected anaplasmosis patients (n?=?101) were analyzed for bacterial DNA contents by singleplex PCR specific for A. phagocytophilum and Ca. N. mikurensis, respectively. One fifth of the neoehrlichiosis patients (4/18) were seropositive for IgM and/or IgG to A. phagocytophilum at the time of diagnosis. Among the patients with suspected anaplasmosis, 2% (2/101) were positive for Ca. N. mikurensis by PCR whereas none (0/101) had detectable A. phagocytophilum DNA in the serum. To conclude, patients with suspected anaplasmosis may in fact have neoehrlichiosis. We found no evidence of A. phagocytophilum and Ca. N. mikurensis co-infections in humans with suspected anaplasmosis or confirmed neoehrlichiosis.     

Expression,cloning, and IgE-binding of the full-length dust mite allergen Der f 8

Dermatophagoides farinae, a domestic mite species, produces some of the most potent allergens that contribute to allergy in China and worldwide. We sought to clone and express the group 8 allergen of D. farinae (Der f 8) to investigate its IgE-binding reactivity. The full-length cDNA encoding Der f 8 was generated by using RT-PCR and 5′ RACE, cloned into pCold-TF expression vector, confirmed by nucleotide sequencing, sub-cloned into pET-28b (+), and transfected into E. coli BL21 cells for expression. After purification by nickel affinity chromatography and identified by SDS-PAGE, the recombinant Der f 8 bound with sera from 40.9 % (9/22) of mite-allergic patients according to ELISA testing. Analysis of the recombinant DNA sequence revealed a 231 amino acid open reading frame encoding a protein with a derived molecular mass of 26.4 kDa and an isoelectric point of 6.84. The deduced amino acid sequence has nine phosphorylation sites, displaying strong homology with glutathione S-transferase, and its secondary structure comprises alpha helix (45.5 %), extended strand (11.3 %), and random coils (43.3 %). BLAST through the National Center for Biotechnology Information database and alignment identified similarity with group 8 allergens or glutathione S-transferases of Dermatophagoides pteronyssinus, Suidasia medanensis, Lepidoglyphus destructor, Glycyphagus domesticus, and Aleuroglyphus ovatus (64, 65, 53, 53, and 50 %, respectively). The first recombinant Der f 8 protein produced in full length successfully bound with patient IgE, demonstrating the importance of Der f 8 in mite allergy.