Borrelia yangtzensis sp. nov., a rodent-associated species in Asia, is related to Borrelia valaisiana.

Twenty-nine isolates of Lyme borreliosis (LB) group spirochaetes collected from ticks and rodents in China and Japan were included in a multilocus sequence analysis (MLSA). Using a different typing system, three of these strains had previously been identified as being divergent from other LB spirochaete species and the name 'Borrelia yangtze' sp. nov. was proposed. The data presented here confirm that the genetic distance, calculated using sequences of MLSA housekeeping genes, to other known LB group spirochaete species was < 95 % and to Borrelia valaisiana was 96.67 % (which represents the most closely related species within the group of LB spirochaetes). This and the fact that these strains are ecologically distinct from B. valaisiana (rodent-transmitted vs bird-transmitted) provide strong support for the validation of the proposed species status. We suggest the name Borrelia yangtzensis sp. nov. The type strain is Okinawa-CW62T ( = DSM 24625T = JCM 17189T).

Borrelia bavariensis sp. nov. is widely distributed in Europe and Asia.

Since the original description of Borrelia bavariensis sp. nov. in 2009, additional samples available from humans and ticks from Europe and Mongolia, respectively, have been used to further characterize Borrelia strains belonging to this group of spirochaetes that utilize rodents as reservoir hosts. These investigations suggested the presence of related strains in Europe and Asia and confirmed their status as representing a distinct species. Furthermore, samples that were investigated by researchers from China and Japan confirm the ecological relationship of members of this proposed species with rodents and suggest that it has a wide distribution in Eurasia. Here, we use phylogenetic and genetic distance analyses to validate B. bavariensis sp. nov. as a species within the Borrelia burgdorferi sensu lato species complex. The type strain is PBi(T) ( = DSM 23469(T) = BAA-2496(T)).

Spatio-temporal analysis of malaria incidence at the village level in a malaria-endemic area in Hainan, China.

BACKGROUND: Malaria incidence in China's Hainan province has dropped significantly, since Malaria Programme of China Global Fund Round 1 was launched. To lay a foundation for further studies to evaluate the efficacy of Malaria Programme and to help with public health planning and resource allocation in the future, the temporal and spatial variations of malaria epidemic are analysed and areas and seasons with a higher risk are identified at a fine geographic scale within a malaria endemic county in Hainan. METHODS: Malaria cases among the residents in each of 37 villages within hyper-endemic areas of Wanning county in southeast Hainan from 2005 to 2009 were geo-coded at village level based on residence once the patients were diagnosed. Based on data so obtained, purely temporal, purely spatial and space-time scan statistics and geographic information systems (GIS) were employed to identify clusters of time, space and space-time with elevated proportions of malaria cases. RESULTS: Purely temporal scan statistics suggested clusters in 2005,2006 and 2007 and no cluster in 2008 and 2009. Purely spatial clustering analyses pinpointed the most likely cluster as including three villages in 2005 and 2006 respectively, sixteen villages in 2007, nine villages in 2008, and five villages in 2009, and the south area of Nanqiao town as the most likely to have a significantly high occurrence of malaria. The space-time clustering analysis found the most likely cluster as including three villages in the south of Nanqiao town with a time frame from January 2005 to May 2007. CONCLUSIONS: Even in a small traditional malaria endemic area, malaria incidence has a significant spatial and temporal heterogeneity on the finer spatial and temporal scales. The scan statistics enable the description of this spatiotemporal heterogeneity, helping with clarifying the epidemiology of malaria and prioritizing the resource assignment and investigation of malaria on a finer geographical scale in endemic areas.

Practicality of Wound Detection Using Smartphone Measure App.

The record of the pressure sore with photo needs to be measurable. We compare the time consumption of wound assessment ruler and measure application of smartphone and the satisfaction of the users. The time needed is 20 and 35 seconds for the ruler and the application on average. But the satisfaction is better for application for its convenience, less infection, and the accuracy of measurements.

Quarantine methods and prevention of secondary outbreak of pandemic (H1N1) 2009.

During the 2009 influenza (H1N1) pandemic, some countries used quarantine for containment or mitigation. Of 152 quarantined university students we studied, risk for illness was higher for students quarantined in a room with a person with a confirmed case; we found no difference between students quarantined in double or single rooms.

Anaplasma phagocytophilum and Borrelia burgdorferi in rabbits from southeastern China.

A total of 54 wild rabbits captured from southeastern China were examined for Anaplasma phagocytophilum and Borrelia burgdorferi sensu lato by polymerase chain reaction (PCR) assays. One and three samples were positive for A. phagocytophilum and B. burgdorferi, respectively. Sequence analyses of PCR products identified a variant of A. phagocytophilum and a B. garinii genotype. This is the first detection of the two tick-borne agents in Chinese rabbits, the role of which in the maintenance of the agents deserve further investigations.

Epidemiological Characteristics and Spatial Analysis of Tick-Borne Encephalitis in Jilin Province, China.

Tick-borne encephalitis (TBE) is a viral infectious disease and has become a reemerging public health threat in recent years in northeastern China. However, no studies has characterized the epidemiologic features and explored the spatial dynamics and environmental factors of TBE cases in Jilin Province. In this study, we have described the epidemiological features of 846 reported human TBE cases from 2006 to 2016 in Jilin Province. There was an obvious single peak pattern of TBE cases from May to July in Jilin Province. More than 60% of TBE cases occurred in farmers, and the people in 50- to 59-year-old group had the high incidence of the disease. The results of Getis-Ord Gi* statistics demonstrated that the human TBE cases were more clustered in the northeastern border including Dunhua and Yanji cities and Antu and Wangqing counties, and southern areas including Huinan, Jingyu, Jiangyuan, and Liuhe counties in Jilin Province. We demonstrated that the temporal dynamics of TBE in Jilin was significantly associated with the dynamics of meteorological factors especially after 2009. The results from the auto-logistic regression analysis showed that the percentage coverage of forest, temperature, and autoregressive term were significantly associated with the occurrence of human TBE cases in Jilin Province. Our findings will provide a scientific evidence for the targeted prevention and control programs.

Novel genospecies of Borrelia burgdorferi sensu lato from rodents and ticks in southwestern China.

By using multilocus sequence analysis, five Borrelia valaisiana-related strains isolated from rodents and ticks in southwestern China were eventually classified as a new genospecies of B. burgdorferi sensu lato rather than B. valaisiana. The finding explained the differences in transmission cycle and phenotype between B. valaisiana strains from Europe and B. valaisiana-related strains from eastern Asia.

Presence of pathogenic Borrelia burgdorferi sensu lato in ticks and rodents in Zhejiang, south-east China.

A molecular epidemiological survey was conducted to investigate the presence of pathogenic Borrelia burgdorferi sensu lato (s.l.) species in the forest areas of Zhejiang province, south-east China. A total of 182 ticks of 6 species and 200 rodents of 8 species were collected and individually examined for the presence of B. burgdorferi s.l. DNA by nested PCR targeting the 5S-23S rRNA intergenic spacer. Forty-one ticks of four species, Haemaphysalis concinna, Haemaphysalis longicornis, Rhipicephalus microplus and Haemaphysalis warburconi, were infected with B. burgdorferi s.l., with an overall infection rate of 23 %. Sixteen rodents of four species, Nivivener confucianus, Nivivener coxingi, Apodemus sylvaticus and Rattus losea, were positive for B. burgdorferi s.l., with an overall prevalence of 8 %. MseI RFLP analysis and sequence analysis of the positive PCR products showed that Borrelia spirochaetes in specimens consisted of Borrelia garinii, Borrelia afzelii and Borrelia valaisiana-related group. Forty (98 %) of the B. burgdorferi s.l.-positive ticks were infected with B. garinii and one (2 %) was infected with B. afzelii. Twelve (75 %) of the positive rodents were infected with B. garinii and four (25 %) were infected with the Borrelia spirochaete belonging to B. valaisiana-related group.

Combined interventions for mitigation of an influenza A (H1N1) 2009 outbreak in a physical training camp in Beijing, China.

OBJECTIVES: Many studies have suggested the effectiveness of single control measures in the containment and mitigation of pandemic influenza A (H1N1) 2009. The effects of combined interventions by multiple control measures in reducing the impact of an influenza A (H1N1) 2009 outbreak in a closed physical training camp in Beijing, China were evaluated. METHODS: Oseltamivir was prescribed for the treatment of confirmed cases and possible cases and as prophylaxis for all other participants in this training camp. Public health control measures were applied simultaneously, including the isolation of patients and possible cases, personal protection and hygiene, and social distancing measures. Symptom surveillance of all participants was initiated, and the actual attack rate was calculated. For comparison, the theoretical attack rate for this outbreak was projected using the Newton-Raphson numerical method. RESULTS: A total of 3256 persons were present at the physical training camp. During the outbreak, 405 (68.3%) possible cases and 26 (4.4%) confirmed cases were reported before the intervention and completed oseltamivir treatment; 162 (27.3%) possible cases were reported after the intervention and received part treatment and part prophylaxis. The other 2663 participants completed oseltamivir prophylaxis. Of the possible cases, 181 with fever ≥38.5°C were isolated. The actual attack rate for this outbreak of pandemic influenza A (H1N1) 2009 was 18.2%, which is much lower than the theoretical attack rate of 80% projected. CONCLUSIONS: Combined interventions of large-scale antiviral ring prophylaxis and treatment and public health control measures could be applied to reduce the magnitude of influenza A (H1N1) 2009 outbreaks in closed settings.

Function of the Borrelia burgdorferi FtsH Homolog Is Essential for Viability both In Vitro and In Vivo and Independent of HflK/C.

UNLABELLED: In many bacteria, the FtsH protease and its modulators, HflK and HflC, form a large protein complex that contributes to both membrane protein quality control and regulation of the cellular response to environmental stress. Both activities are crucial to the Lyme disease pathogen Borrelia burgdorferi, which depends on membrane functions, such as motility, protein transport, and cell signaling, to respond to rapid changes in its environment. Using an inducible system, we demonstrate that FtsH production is essential for both mouse and tick infectivity and for in vitro growth of B. burgdorferi FtsH depletion in B. burgdorferi cells resulted in membrane deformation and cell death. Overproduction of the protease did not have any detectable adverse effects on B. burgdorferi growth in vitro, suggesting that excess FtsH does not proteolytically overwhelm its substrates. In contrast, we did not observe any phenotype for cells lacking the protease modulators HflK and HflC (ΔHflK/C), although we examined morphology, growth rate, growth under stress conditions, and the complete mouse-tick infectious cycle. Our results demonstrate that FtsH provides an essential function in the life cycle of the obligate pathogen B. burgdorferi but that HflK and HflC do not detectably affect FtsH function. IMPORTANCE: Lyme disease is caused by Borrelia burgdorferi, which is maintained in nature in an infectious cycle alternating between small mammals and Ixodes ticks. B. burgdorferi produces specific membrane proteins to successfully infect and persist in these diverse organisms. We hypothesized that B. burgdorferi has a specific mechanism to ensure that membrane proteins are properly folded and biologically active when needed and removed if improperly folded or dysfunctional. Our experiments demonstrate that FtsH, a protease that fulfills this role in other microorganisms, is essential to B. burgdorferi viability. Cells depleted of FtsH do not survive in laboratory culture medium and cannot colonize mice or ticks, revealing an absolute requirement for this protease. However, the loss of two potential modulators of FtsH activity, HflK and HflC, does not detectably affect B. burgdorferi physiology. Our results provide the groundwork for the identification of FtsH substrates that are critical for the bacterium's viability.

Transmission characteristics of different students during a school outbreak of (H1N1) pdm09 influenza in China, 2009.

Many outbreaks of A(H1N1)pdm09 influenza have occurred in schools with a high population density. Containment of school outbreaks is predicted to help mitigate pandemic influenza. Understanding disease transmission characteristics within the school setting is critical to implementing effective control measures. Based on a school outbreak survey, we found almost all (93.7%) disease transmission occurred within a single grade, only 6.3% crossed grades. Transmissions originating from freshmen exhibited a star-shaped network; other grades exhibited branch- or line-shaped networks, indicating freshmen have higher activity and are more likely to cause infection. R0 for freshmen, calculated as 2.04, estimated as 2.76, was greater than for other grades (P < 0.01). Without intervention, the estimated number of cases was much greater when the outbreak was initiated by freshmen than by other grades. Furthermore, the estimated number of cases required to be under quarantine and isolation for freshmen was less than that of equivalent other grades. So we concluded that different grades have different transmission mode. Freshmen were the main facilitators of the spread of A(H1N1)pdm09 influenza during this school outbreak, so control measures (e.g. close contact isolation) priority used for freshmen would likely have effectively reduced spread of influenza in school settings.

Spatial spread and demographic expansion of Lyme borreliosis spirochaetes in Eurasia.

The Lyme borreliosis (LB) group of spirochaetes currently comprises 18 named species that vary in their geographic distribution, host specificity and ability to cause disease in humans. In Europe three species are most abundant, Borrelia afzelii, Borrelia garinii and Borrelia valaisiana but only two of these (B. garinii and B. afzelii) are regularly found in Asia as well. A recently published study has shown that Borrelia species associated with birds, such as B. garinii, showed limited geographic structuring between European countries while, the rodent associated species, B. afzelii, showed extensive spatial structuring in Europe. Here, we use multilocus sequence analysis to show that when the wider, inter-continental, distribution is considered, there is evidence of spatial structuring even in the bird-associated species B. garinii. Furthermore, our investigations into historical LB populations provided evidence for range expansions of B. garinii and B. afzelii populations in Europe in the distant past. We propose that the expansion of B. afzelii in Europe may be linked to rodent population expansions after the last glacial maximum.

Genetic diversity of Borrelia burgdorferi sensu lato isolates from Northeastern China.

Thirty-two strains of Borrelia burgdorferi sensu lato were isolated from Ixodes persulcatus ticks collected from northeastern China from May to June in 2004 and 2005. Restriction fragment length polymorphism (RFLP) analysis and sequence analysis of 5S-23S rRNA intergenic spacer revealed that 29 (90.6%) belonged to Borrelia garinii, demonstrating B, C, and a unique pattern. The remaining three isolates (9.4%) were Borrelia afzelii with pattern D. The phylogenetic analysis based on 5S-23S rRNA intergenic spacer showed that B. garinii and B. afzelii genospecies clustered into two separate lineages. B. garinii strains were classified into three different branches: All the strains with RFLP pattern C were in the same branch, strain VH10 with a unique RFLP pattern clustered with strains VH9 and MDH2 with pattern B, and the rest of the strains with pattern B constitute another branch. These findings demonstrate the genetic diversity of B. burgdorferi sensu lato isolates from northeastern China.

Genetic diversity of Borrelia burgdorferi sensu lato isolates from Northeastern China.

Thirty-two strains of Borrelia burgdorferi sensu lato were isolated from Ixodes persulcatus ticks collected from northeastern China from May to June in 2004 and 2005. Restriction fragment length polymorphism (RFLP) analysis and sequence analysis of 5S-23S rRNA intergenic spacer revealed that 29 (90.6%) belonged to Borrelia garinii, demonstrating B, C, and a unique pattern. The remaining three isolates (9.4%) were Borrelia afzelii with pattern D. The phylogenetic analysis based on 5S-23S rRNA intergenic spacer showed that B. garinii and B. afzelii genospecies clustered into two separate lineages. B. garinii strains were classified into three different branches: All the strains with RFLP pattern C were in the same branch, strain VH10 with a unique RFLP pattern clustered with strains VH9 and MDH2 with pattern B, and the rest of the strains with pattern B constitute another branch. These findings demonstrate the genetic diversity of B. burgdorferi sensu lato isolates from northeastern China.

[Identification of Amur like virus in Apodemus peninsulae and its molecular characteristics in China].

OBJECTIVE: To confirm the existence of Amur-like viruses in Apodemus peninsulae in China, and to understand the molecular characteristics of these viruses. METHODS: Total RNA was extracted from lungs of A. peninsulae captured in Jilin of Northeast China with Trizol reagent. Complete S and partial M segments of Amur virus were amplified and sequenced. Phylogenetic analyses on multiple nucleotide sequences were performed with the Clustal method and DNASTAR software. RESULTS: 383 bp cDNA of M segment and 1696 bp of S segment of Amur like virus were recovered from lung tissue of A. peninsulae, named JilinAP06. The full-length of its S gene comprised of 1696 nucleotides with ORF including 1287 nucleotides and encoding a protein which comprised 429 amino acids. The phylogenetic analysis of this sample with other hantaviruses revealed that the complete S and partial M segment sequence of JilinAP06 both were closely related to those Amur viruses such as AP63, AP61, AP1371 and AP1168 found in A. peninsulae from Far East region of Russia and B78 strain, Liu strain and H5 strain, which were all from Chinese patients. The complete S and partial M segment sequence of JilinAP06 had only 81.0% identities with the nucleotide sequences of HV prototype 76-118 strain. CONCLUSION: Amur-like viruses did exist in A. peninsulae from Northeasern China while A. peninsulae might be the natural reservoir of Amur-like viruses in China and was the important infectious source to HFRS patients which were caused by Amur-like viruses.

[Investigation on Anaplasma phagocytophilum infection in rodents from forest areas in northeastern China].

OBJECTIVE: To investigate the prevalence of Anaplasma phagocytophilum in rodents from forest areas in northeastern China. METHODS: PCR amplification, followed by sequence analysis was carried out. The sequences of 16S rRNA and gltA gene fragment amplified from rodent specimens were compared with corresponding part of the sequences deposited in GenBank. RESULTS: A total number of 276 rodents were tested, including 102 in Jilin province, 61 in Helongjiang province and 113 in Inner Mongolia autonomous region. The positive rates were 8.82%, 1.64% and 0.00%, respectively. The infection rate in rodents infected by ticks was 11.30 times higher than that in rodents without ticks (P = 0.002). The S. A. phagocytophilum 16S rRNA sequences from rodents in Jilin and Heilongjiang were identical and differed in 3-5 bases compared with the corresponding parts of A. phagocytophilum from America, Sweden and Japan. Compared with the sequences registered in GenBank, the nucleotide sequence of gltA varied from 87%-97% and its deduced amino acid sequence changed from 84%-99%. CONCLUSION: A. phagocytophilum infection was presented in rodents from Jilin and Heilongjiang province.

[Investigation on Borrelia burgdorferi sensu lato in ticks and rodents collected in Da Xing-An Mountains Forest areas of China].

OBJECTIVE: To detect and study the types of Borrelia burgdorferi sensu lato in ticks and rodents from Da Xing-An Mountains Forest areas of China. METHODS: Nested PCR was performed to amplify 5S-23S rRNA intergenic spacer of B. burgdorferi. Positive products were analysed by restriction fragment length polymorphism (RFLP) and single strand conformation polymorphism (SSCP), specimens showing unique RFLP profile were sequenced and analysed. RESULTS: 1336 Ixodes persulcatus, 144 Dermacento silvarum, 144 Haemaphysalis concinna and 145 rodents of 9 species were collected from 16 sections of Da Xing-An Mountains Forest areas of China. Specific fragments were amplified from 293 I. persulcatus and 6 D. silvarum and 5 rodents of 4 species. B. burgdorferi was not detected in H. concinna. Among the positively tested I. persulcatus, 209 contained B. garinii genospecies and 45 contained B.afzelii genospecies based on RFLP. Moreover, B.garinii genospecies consisted of B. garinii 20047 and B. garinii NT29. 17 adult I. persulcatus were simultaneously infected with B. garinii 20047 and B. garinii NT29. Nine adult I. persulcatus were simultaneously infected with B. garinii 20047 and B. afzelii. Four adult I. persulcatus were simultaneously infected with B. garinii 20047 and B. garinii NT29 and B. afzelii. Two D. silvarum were infected with B. garinii 20047, 1 D. silvarum with B. garinii 20047, 2 D. silvarum with B. afzelii. 3 rodents were infected with B. garinii 20047 while 2 rodents were infected with B. garinii NT29. Mixed infection was not found in D. silvarum and rodents. In addition, nine I. persulcatus and one D. silvarum specimens showed unique RFLP pattern. Data from sequential analysis showed that they all belonged to B. garinii. PCR-SSCP profiles of 5S-23S rRNA intergenic spacer of B. burgdorferi in the positive specimens exceeded 36 types; B. garinii 20047 showed 16 types while B. garinii NT29 showing 11 types, B. afzelii showing 9 types. SSCP profiles of the specimens coinfected with multiple B. burgdorferi was relatively complex. CONCLUSION: The infection of B. burgdorferi was found in the ticks and rodents in Da Xing-An Mountains Forests areas. The infection rate of I. persulcatus was high. B. garinii was predominant genospecies, and the population of B. burgdorferi was heterogeneous in the area. Mixed infections of different B. burgdorferi genospecies in ticks were found. I. persulcatus and Clethrionomys rufocanus were possibly served as major vector and major host for B. burgdorferi, respectively, suggesting that further study is needed to confirm the coinfection in humans and animals in this region.