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Although anaplasmosis cases have been nationally identified in China, no human isolates of A. phagocytophilum have been obtained, which limits the analysis of any molecular and genetic contributions to patients' severe clinical manifestations and the study of the bacteria's pathogeneses in China. Given this situation, a joint project was conducted in 2009–2010. A total of 421 febrile cases of unknown etiology were collected and the patients' blood samples were collected for laboratory diagnoses including serologic diagnosis based on the four-fold rise in the anti- A. phagocytophilum IgG titer by indirect micro-immunofluorescence assay (IFA), positive PCR assay and confirmation of A. phagocytophilum DNA and positive culture of A. phagocytophilum and confirmed by amplification and sequencing of the 16S rRNA and ank A genes of the A. phagocytophilum isolates. A total of 570 ticks were collected from the patients' domestic animals (456) and from wild fields (114) for culturing and amplifying and sequencing the 16S rRNA gene of A. phagocytophilum. Phylogenetic analyses were performed on the 16S rRNA and ank A gene sequences of the isolates and the ticks tested in the study. A total of 46 (10.9%) confirmed and 16 (3.8%) probable cases were diagnosed and severe clinical features and higher mortality rates were observed in these Chinese patients. Five isolates were obtained and the 16S rRNA genes of the 5 isolates were conserved but variety for ank A genes. Two human isolates and 1 tick isolate from Shandong Peninsula, where all patients exhibited severe clinical manifestations, were grouped as one clan based on the phylogenetic analyses, while 2 other human isolates were clustered in a second clan. 43.5% of H. longicornis were infected with A. phagocytophilum.The present study is the first to obtain clinical isolates of A. phagocytophilum in China. The diversity of the ank A genes of Chinese isolates will help us to further discern the relationship between the variations in the ank A genes and the severity of the disease's clinical manifestations in China. [ABSTRACT FROM AUTHOR]

• The contribution of oyster reefs characteristics to the omnivorous fish intestinal microbiota was distinct. • Microbial communities in the oyster reefs and fish intestines showed various predictive functions and unique core indicators. • The microbial diversity in sediments were significantly higher than that in intestines. The habitats of oyster reefs had played various ecological services functions, as an important means of marine ecological restoration and fishery resources conservation, which had been widely used worldwide. And the characteristics of microbial communities would be inevitably affected by habitat of oyster reefs. The aim of this study was to reveal the relationship between oyster reefs and the intestinal microbiota of fish (Takifugu ocellatus , Acanthopagrus latus , Clupanodon thrissa , and Mugil cephalus). Here, based on 16S rRNA sequencing, this research analyzed the microbial communities of fishes gut in the oyster reefs from the most crucial estuary economic zone in Southern China. It was significantly lower that the bacterial alpha-diversity in the fish intestines than in the sediments of oyster reefs. The non-metric multidimensional scaling (NMDS) and analysis of similarities (ANOSIM) results showed that intestines microbiota of T. ocellatus and A. latus were more homologous to sediments microbiota, but intestines microbiota of C. thrissa and M. cephalus were more similar to the water microbiota. There were obvious differences in the contribution of oyster reefs habitat to intestinal microorganisms of four fishes. Source tracking analysis as well reached the similar conclusion. For instance, contribution of water to T. ocellatus and A. latus was lesser than sediments, which was related to their benthic habits. Based on the differences in microbial community compositions, the functional prediction analysis had demonstrated that special functional pathways and independent core indicators had been formed separately from oyster reefs and fish intestines. Overall, these findings highlighted the characteristics of microbial diversity and functions from the omnivorous fish living in oyster reefs habitats. This research proposed new insights into the function of oyster reefs habitats, which have enriched the ecological service value of oyster reefs from microbial ecology and provided a reference for the application of oyster reefs habitats in other estuaries. [ABSTRACT FROM AUTHOR]

• A multi-dimensional functional space was built to visualize the functional structure. • The functional structure and trait composition of fish in the PRE vary seasonally. • The CWM traits were mainly affected by temperature, DO, chlorophyll-a, and depth. Estuaries are one of the most important ecosystems with high biological productivity. They connect freshwater and marine ecosystems, and the fish community assemblages face intense environmental changes, so estuarine fish communities have unique ecological characteristics. With the increase of human activities and the discharge of pollutants, the pressure on the ecosystem of the Pearl River Estuary (PRE) is intensifying, and its ecosystem functions and services are inevitably affected. To better understand the functional structure of the fish community in the PRE and its response to environmental changes, we analyzed the trait composition of the community and its relationships to environmental factors based on 10 functional traits of 130 fish species collected in the PRE during the summer and winter of 2020–2021. In addition, we built a multi-dimensional functional space to visualize the overall functional structure of the PRE and explore the seasonal variation of the selected traits in the functional space. Our findings suggest that the functional traits of the fish communities in the PRE were mainly affected by temperature, dissolved oxygen, chlorophyll-a, and depth. Among them, the effects of dissolved oxygen, temperature, and chlorophyll-a on CWM traits were reflected in seasonal differences, while the effects of depth were reflected in spatial differences. We also found the main trait categories that occupied the most functional space and contributed the most to the seasonal differences in functional space. The results of this study are significant for understanding the seasonal variation of the functional structure in the PRE and how environmental gradients drive the functional traits of fish communities, and also provide insights for effective ecosystem-based management in the PRE. [ABSTRACT FROM AUTHOR]

As emerging tick born rickettsial diseases caused by A. phagocytophilum and E. chaffeensis, anaplasmosis and ehrlichiosis have become a serious threat to human and animal health throughout the world. In particular, in China, an unusual transmission of nosocomial cases of human granulocytic anaplasmosis occurred in Anhui Province in 2006 and more recent coinfection case of A. phagocytophilum and E. chaffeensis was documented in Shandong Province. Although the seroprevalence of human granulocytic anaplasmosis (former human granulocytic ehrlichiosis, HGE) has been documented in several studies, these data existed on local investigations, and also little data was reported on the seroprevalence of human monocytic ehrlichiosis (HME) in China. In this cross-sectional epidemiological study, indirect immunofluorescence antibody assay (IFA) proposed by WHO was used to detect A. phagocytophilum and E. chaffeensis IgG antibodies for 7,322 serum samples from agrarian residents from 9 provinces/cities and 819 urban residents from 2 provinces. Our data showed that farmers were at substantially increased risk of exposure. However, even among urban residents, risk was considerable. Seroprevalence of HGA and HME occurred in diverse regions of the country and tended to be the highest in young adults. Many species of ticks were confirmed carrying A. phagocytophilum organisms in China while several kinds of domestic animals including dog, goats, sheep, cattle, horse, wild rabbit, and some small wild rodents were proposed to be the reservoir hosts of A. phagocytophilum. The broad distribution of vector and hosts of the A. phagocytophilum and E. chaffeensis, especially the relationship between the generalized susceptibility of vectors and reservoirs and the severity of the disease's clinical manifestations and the genetic variation of Chinese HGA isolates in China, is urgently needed to be further investigated.

Although anaplasmosis cases have been nationally identified in China, no human isolates of A. phagocytophilum have been obtained, which limits the analysis of any molecular and genetic contributions to patients' severe clinical manifestations and the study of the bacteria's pathogeneses in China. Given this situation, a joint project was conducted in 2009-2010. A total of 421 febrile cases of unknown etiology were collected and the patients' blood samples were collected for laboratory diagnoses including serologic diagnosis based on the four-fold rise in the anti- A. phagocytophilum IgG titer by indirect micro-immunofluorescence assay (IFA), positive PCR assay and confirmation of A. phagocytophilum DNA and positive culture of A. phagocytophilum and confirmed by amplification and sequencing of the 16S rRNA and ank A genes of the A. phagocytophilum isolates. A total of 570 ticks were collected from the patients' domestic animals (456) and from wild fields (114) for culturing and amplifying and sequencing the 16S rRNA gene of A. phagocytophilum. Phylogenetic analyses were performed on the 16S rRNA and ank A gene sequences of the isolates and the ticks tested in the study. A total of 46 (10.9%) confirmed and 16 (3.8%) probable cases were diagnosed and severe clinical features and higher mortality rates were observed in these Chinese patients. Five isolates were obtained and the 16S rRNA genes of the 5 isolates were conserved but variety for ank A genes. Two human isolates and 1 tick isolate from Shandong Peninsula, where all patients exhibited severe clinical manifestations, were grouped as one clan based on the phylogenetic analyses, while 2 other human isolates were clustered in a second clan. 43.5% of H. longicornis were infected with A. phagocytophilum.The present study is the first to obtain clinical isolates of A. phagocytophilum in China. The diversity of the ank A genes of Chinese isolates will help us to further discern the relationship between the variations in the ank A genes and the severity of the disease's clinical manifestations in China.

Objectives: To describe clinical characteristics of severe acute respiratory syndrome (SARS) patients in a hospital in Tianjin, China, thereby comparing probable and suspected cases; to study risk factors associated with the death of cases; to describe the implementation of preventive interventions during the hospital outbreak., Methods: Physical and haematological information was obtained from clinical records. White blood cell counts, and percentages of neutrophilic granulocytes and neutrophilic lymphocytes were measured. The service department of the hospital provided information about daily use of protective materials. Differences in clinical symptoms between probable and suspected SARS cases were tested by Fisher's exact test. Non-linear mixed modelling was used to test for differences between the haematological patterns for probable and suspected cases. Risk factors for dying among probable SARS cases were tested by logistic regression., Results: The SARS outbreak started with a patient from Beijing on 15 April 2003, and spread quickly among the healthcare workers and in-patients in the hospital. In total 90 probable and 21 suspected cases were reported, with 17 deaths among them (case fatality rate 15%). Haematological patterns were significantly different between probable and suspected cases, whereas the percentages with certain clinical symptoms showed no apparent difference. Death of probable SARS cases was only significantly associated with high age and use of a respiratory machine (mainly for the most severe cases), whereas e.g. co-morbidity and steroid treatment showed no impact in multivariate analysis. Stringent control measures, including distribution of huge numbers of protective materials, started on 20 April, which soon lead to a strong decrease in the incidence of new cases. After the last SARS case left the hospital on 6 June, protective materials were dispensed at substantially lower rates, but not to zero, as was the case during the first days of the outbreak., Conclusion: The working definition of probable SARS used during the epidemic appeared to have been fairly accurate. Many valuable lessons were learned regarding prevention of hospital spread of infection, especially the need to have sufficient protective supplies available and to implement these rigidly and at an early stage of an (threatening) epidemic.

Background: Host genetic factors may play a role in the occurrence and progress of SARS-Cov infection. This study was to investigate the relationship between tumor necrosis factor (TNF)-alpha gene polymorphisms with the occurrence of SARS-CoV infection and its role in prognosis of patients with lung interstitial fibrosis and femoral head osteonecrosis., Methods: The association between genetic polymorphisms of TNF-alpha gene and susceptibility to severe acute respiratory syndromes (SARS) was conducted in a hospital-based case-control study including 75 SARS patients, 41 health care workers and 92 healthy controls. Relationships of TNF-alpha gene polymorphisms with interstitial lung fibrosis and femoral head osteonecrosis were carried out in two case-case studies in discharged SARS patients. PCR sequencing based typing (PCR-SBT) method was used to determine the polymorphisms of TNF-alpha gene in locus of the promoter region and univariate logistic analysis was conducted in analyzing the collected data., Results: Compared to TT genotype, the CT genotype at the -204 locus was found associated with a protective effect on SARS with OR(95%CI) of 0.95(0.90-0.99). Also, TT genotype, CT and CC were found associated with a risk effect on femoral head necrosis with ORs(95%CI) of 5.33(1.39-20.45) and 5.67(2.74-11.71), respectively and the glucocorticoid adjusted OR of CT was 5.25(95%CI 1.18-23.46) and the combined (CT and CC) genotype OR was 6.0 (95%CI 1.60-22.55) at -1031 site of TNF-alpha gene. At the same time, the -863 AC genotype was manifested as another risk effect associated with femoral head necrosis with OR(95%CI) of 6.42(1.53-26.88) and the adjusted OR was 8.40(95%CI 1.76-40.02) in cured SARS patients compared to CC genotype., Conclusion: SNPs of TNF-alpha gene of promoter region may not associate with SARS-CoV infection. And these SNPs may not affect interstitial lung fibrosis in cured SARS patients. However, the -1031CT/CC and -863 AC genotypes may be risk factors of femoral head necrosis in discharged SARS patients.