Incidence and warning signs for complications of human brucellosis: a multi-center observational study from China

BACKGROUND

Brucellosis is a severe zoonotic disease that is often overlooked, particularly in impoverished countries. Timely identification of focal complications in brucellosis is crucial for improving treatment outcomes. However, there is currently a lack of established indicators or biomarkers for diagnosing these complications. Therefore, this study aimed to investigate potential warning signs of focal complications in human brucellosis, with the goal of providing practical parameters for clinicians to aid in the diagnosis and management of patients.

METHODS

A multi-center cross-sectional study was conducted in China from December 2019 to August 2021. The study aimed to investigate the clinical characteristics and complications of patients with brucellosis using a questionnaire survey and medical record system. The presence of warning signs for complications was assessed using univariate and multivariate logistic regression models. Receiver operating characteristic (ROC) curves and the area under the curve (AUC) were used for variable screening and model evaluation.

RESULTS

A total of 880 participants diagnosed with human brucellosis were enrolled. The median age of the patients was 50 years [interquartile range (IQR): 41.5-58.0], and 54.8% had complications. The most common organ system affected by complications was the osteoarticular system (43.1%), with peripheral arthritis (30.0%), spondylitis (16.6%), paravertebral abscess (5.0%), and sacroiliitis (2.7%) being the most prevalent. Complications in other organ systems included the genitourinary system (4.7%), respiratory system (4.7%), and hematologic system (4.6%). Several factors were found to be associated with focal brucellosis. These factors included a long delay in diagnosis [odds ratio (OR) = 3.963, 95% confidence interval (CI) 1.906-8.238 for > 90 days], the presence of underlying disease (OR = 1.675, 95% CI 1.176-2.384), arthralgia (OR = 3.197, 95% CI 1.986-5.148), eye bulging pain (OR = 3.482, 95% CI 1.349-8.988), C-reactive protein (CRP) > 10 mg/L (OR = 1.910, 95% CI 1.310-2.784) and erythrocyte sedimentation rate (ESR) elevation (OR = 1.663, 95% CI 1.145-2.415). The optimal cutoff value in ROC analysis was > 5.4 mg/L for CRP (sensitivity 73.4% and specificity 51.9%) and > 25 mm/h for ESR (sensitivity 47.9% and specificity 71.1%).

CONCLUSIONS

More than 50% of patients with brucellosis experienced complications. Factors such as diagnostic delay, underlying disease, arthralgia, eye pain, and elevated levels of CRP and ESR were identified as significant markers for the development of complications. Therefore, patients presenting with these conditions should be closely monitored for potential complications, regardless of their culture results and standard tube agglutination test titers.

[Interpretation of the National Regulation for the Rabies Exposure Prophylaxis (2023 Edition)]

Rabies is one of the important zoonotic infectious diseases, with a mortality rate of almost 100%. Rabies is a vaccine preventable disease, and proper rabies exposure prophylaxis can effectively prevent the occurrence of human rabies. In recent years, there has been significant progress in clinical research on the rabies exposure prophylaxis both domestically and internationally. World Health Organization (WHO) released the Rabies Vaccine: WHO Position Paper-April 2018. In order to guide medical institutions of all levels in rabies exposure prophylaxis, the National Administration of Disease Prevention and Control, in conjunction with the National Health Commission of the People's Republic of China, organized the Rabies Vaccine Working Group of the National Immunization Program Technical Working Group and invited experts to revise and issue the National Regulation for the Rabies Exposure Prophylaxis (2023 Edition). This article compares the National Regulation for the Rabies Exposure Prophylaxis (2009 Edition) and interprets the updated key points and supporting basis of the new version of the guidelines to guide clinical application and implementation.

[Progress and prospect of clinical application of anti-rabies virus monoclonal antibody preparation]

Rabies is a severe infectious disease caused by the rabies virus, which seriously damages the central nervous system. Once it occurs, the fatality rate is close to 100%. The World Health Organization's position paper on rabies vaccines recognizes that rabies immunoglobulin (RIG) should be used for post-exposure prophylaxis (PEP) in all category Ⅲ exposure for the first time, as well as in category Ⅱ exposure that suffer from severe immune deficiency, long-term massive use of immunosuppressants, and head and face exposure. The anti-rabies virus monoclonal antibody has high purity and specific activity, can be produced on a sustainable scale, and has no risk of blood source virus contamination. Preclinical pharmacodynamic studies and clinical trial results of the anti-rabies virus monoclonal antibody preparation have confirmed that the preparation has a broad-spectrum neutralization effect on the rabies virus. Additionally, its combined application with the vaccine has little impact on the active immunity of the vaccine. Therefore, the anti-rabies virus monoclonal antibody preparation shows great potential for clinical application in PEP.

[Epidemiological characteristics of severe fever with thtrombocytopenia syndrome in China, 2011-2021]

Objective: To analyze the epidemiological characteristics of severe fever with thrombocytopenia syndrome (SFTS) in China from 2011 to 2021, and provide evidence for the prevention and control of SFTS. Methods: The incidence data of SFTS were collected from the National Disease Reporting Information System of Chinese Center for Disease Control and Prevention for a descriptive epidemiological analysis and Cochran-Armitage trend test was used to evaluate the association between age and the morbidity rate and case fatality rate (CFR) of SFTS. Results: From 2011 to 2021, a total of 18 902 laboratory confirmed cases of SFTS, including 966 deaths, were reported in 533 counties (districts) of 154 prefecture-level cities in 27 provinces. The annual average morbidity rate was 0.125/100 000, and the annual average CFR was 5.11%. From 2011 to 2021 the overall morbidity rate of SFTS was in increase with an average annual percentage change (AAPC) of 14.80% (P=0.001). Most cases (99.23%) occurred in 7 provinces, including Shandong, Henan, Anhui, Hubei, Liaoning, Zhejiang and Jiangsu, with 70.28% of the cases in 11 prefecture-level cities. The average annual CFRs in the 7 provinces varied greatly from 1.30% to 11.27%. In 2011, SFTS cases were reported in 108 counties (districts) of 51 prefecture-level cities in 13 provinces, but SFTS cases were reported in 277 counties (districts) of 88 prefecture-level cities in 19 provinces in 2021, the disease spread from central area to the northeast and from the west and the south. SFTS mainly occurred in summer and autumn in both southern and northern China, and 96.63% of the cases were reported from April to October, and the incidence peak was during May-June. The cases mainly occurred in age group 50-74 years (69.46%), and the deaths mainly occurred in age group ≥60 years (79.71%). Both the morbidity rate and the CFR increased with age. The morbidity rate increased from 0.040/100 000 in age group 0-4 years to 4.480/100 000 in age group ≥80 years in males (χ²=13 185.21, P<0.001) and from 0.038/100 000 in age group 0-4 years to 3.318/100 000 in age group ≥80 years in females (χ²=12 939.83, P<0.001); the CFR increased from 0.70% in age group 30-34 years to 11.58% in age group ≥80 years in males (χ²=115.70, P<0.001) and from 1.56% in age group 35-39 years to 8.98% in age group ≥80 years in females (χ²=103.42, P<0.001). Conclusion: From 2011 to 2021, the incidence of SFTS increased in China, and the spread and obvious spatiotemporal distribution of SFTS were observed. The reported CFR varied greatly with area, and both the morbidity and mortality risk were high in the elderly.

[Meta analysis on acceptance rate of HIV pre-exposure prophylaxis among men who have sex with men in China]

Objective: To systematically evaluate the acceptance of pre-exposure prophylaxis (PrEP)among men who have sex with men (MSM) in China, so as to provide reference for the promotion of preventive drug use before human immunodeficiency virus exposure in China. Methods: By searching the databases of China national knowledge infrastructure, VIP database, Wanfan knowledge service platform, PubMed, Web of Science, Embase and The Cochrane Library with key words of "men who have sex with men" "pre-exposure prophylaxis" "PrEP" and "MSM". The literature on the willingness of Chinese MSM population to accept PrEP was systematically collected, and the data of the literature meeting the inclusion criteria were extracted for Meta analysis. Results: A total of 12 articles were selected in this study, including 6 articles in English and 6 in Chinese. The score of bias risk assessment of eligible articles was 14-18, which was more than 70% of the total score. The total number of samples was 11 269. The overall acceptance rate of PrEP was 0.77(95%CI:0.71-0.82). In subgroup analysis, the acceptance rates of different nationalities, marriage, household registration, age, education background, income, sexual orientation, sexual behavior and awareness of PrEP were statistically significant. Conclusion: In general, the acceptance rate of PrEP in MSM population is higher, but the awareness rate is low. There are differences in the acceptance rate among different groups.

Spatial distribution of leptospirosis incidence in the Upper Yangtze and Pearl River Basin, China: Tools to support intervention and elimination

BACKGROUND

Since 2011 human leptospirosis incidence in China has remained steadily low with persistent pockets of notifications reported in communities within the Upper Yangtze River Basin (UYRB) and Pearl River Basin (PRB). To help guide health authorities within these residual areas to identify communities where interventions should be targeted, this study quantified the local effect of socioeconomic and environmental factors on the spatial distribution of leptospirosis incidence and developed predictive maps of leptospirosis incidence for UYRB and PRB.

METHODS

Data on all human leptospirosis cases reported during 2005-2016 across the UYRB and PRB regions were geolocated at the county-level and included in the analysis. Bayesian conditional autoregressive (CAR) models with zero-inflated Poisson link for leptospirosis incidence were developed after adjustment of environmental and socioeconomic factors such as precipitation, normalized difference vegetation index (NDVI), modified normalized difference water index (MNDWI), land surface temperature (LST), elevation, slope, land cover, crop production, livestock density, gross domestic product and population density.

RESULTS

The relationship of environmental and socioeconomic variables with human leptospirosis incidence varied between both regions. While across UYRB incidence of human leptospirosis was associated with MNDWI and elevation, in PRB human leptospirosis incidence was significantly associated with NDVI, livestock density and land cover. Precipitation was significantly and positively associated with the spatial variation of incidence of leptospirosis in both regions. After accounting for the effect of environmental and socioeconomic factors, the predicted distribution of residual high-incidence county is potentially more widespread both in the UYRB and PRB compared to the observed distribution. In the UYRB, the highest predicted incidence was found along the border of Chongqing and Guizhou towards Sichuan basin and northwest Yunnan. The highest predicted incidence was also identified in counties in the central and lower reaches of the PRB.

CONCLUSIONS

This study demonstrated significant geographical heterogeneity in leptospirosis incidence within UYRB and PRB, providing an evidence base for prioritising targeted interventions in counties identified with the highest predicted incidence. Furthermore, environmental drivers of leptospirosis incidence were highly specific to each of the regions, emphasizing the importance of localized control measures. The findings also suggested the need to expand interventional coverage and to support surveillance and diagnostic capacity on the predicted high-risk areas.

[Early containment strategies and core measures for prevention and control of novel coronavirus pneumonia in China]

In December 2019, novel coronavirus pneumonia epidemic occurred in Wuhan, Hubei Province, and spread rapidly across the country. In the early stages of the epidemic, China adopted the containment strategy and implemented a series of core measures around this strategic point, including social mobilization, strengthening case isolation and close contacts tracking management, blocking epidemic areas and traffic control to reduce personnel movements and increase social distance, environmental measures and personal protection, with a view to controlling the epidemic as soon as possible in limited areas such as Wuhan. This article summarizes the background, key points and core measures in the country and provinces. It sent prospects for future prevention and control strategies.

[Expert consensus on rabies exposure prophylaxis]

Rabies is a zoonotic infectious disease caused by lyssavirus and characterized by central nervous system symptoms. The fatality rate of rabies is almost 100%. About 59 000 cases die of rabies worldwide every year, mainly in Asia and Africa. China is an epidemic country of rabies. Grade II and III exposures are the main types of rabies exposures in China. Standardized post-exposure prophylaxis (PEP) can prevent rabies almost 100%. Human Rabies Vaccine Technical Working Group, National Immunization Advisory Committee and invited experts reached an expert consensus on PEP by referring to the World Health Organization's position paper on rabies vaccine in 2018 and related research progress in recent.

Climate variability, satellite-derived physical environmental data and human leptospirosis: A retrospective ecological study in China

BACKGROUND

In the past three decades, the incidence rate of notified leptospirosis cases in China have steeply declined and are now circumscribed to discrete areas in the country. Previous research showed that climate and environmental variation may play an important role in leptospirosis transmission. However, quantitative associations between climate, environmental factors and leptospirosis in the high-risk areas in China, is still poorly understood.

OBJECTIVE

To quantify the temporal effects of climate and remotely-sensed physical environmental factors on human leptospirosis in the high-risk counties in China.

METHODS

Time series seasonal decomposition was performed to explore the seasonality pattern of leptospirosis incidence in Mengla County, Yunnan and Yilong County, Sichuan for the period 2006-2016. Time series cross-correlation analysis was carried out to examine lagged effects of rainfall, relative humidity, normalized difference vegetation index (NDVI), modified normalized difference water index (MNDWI) and land surface temperature (LST) on leptospirosis. The associations of climatic and physical environment factors with leptospirosis in each county were assessed by using a generalized linear regression model with negative binomial link, adjusted by seasonal components.

RESULTS

Leptospirosis incidence in both counties showed strong and unique annual seasonality. Our results show that in Mengla County leptospirosis notifications exhibits a bi-modal temporal pattern while in Yilong County it follows a typical single epidemic curve. After adjusting for seasonality, the final best-fitting model for Mengla County indicated that leptospirosis notifications were significantly associated with present LST values (incidence rate ratio, IRR = 0.857, 95% confidence interval (CI):0.729-0.929) and rainfall at a lag of 6-months (IRR = 0.989; 95% CI: 0.985-0.993). The incidence of leptospirosis in Yilong was associated with rainfall at 1-month lag (IRR = 1.013, 95% CI: 1.003-1.023), LST (3-months lag) (IRR = 1.193, 95% CI: 1.095-1.301), and MNDWI (5-months lag) (IRR = 7.960, 95% CI: 1.241-47.66).

CONCLUSIONS

Our study identified lagged effects between leptospirosis incidence and climate and remotely-sensed environmental factors in the two most endemic counties in China. Rainfall in combination with satellite derived physical environment factors provided better insight of the local epidemiology as well as good predictors for leptospirosis outbreak in both counties. This would also be an avenue for the development of leptospirosis early warning systems to support leptospirosis control in China.

[Expert consensus on rabies exposure prophylaxis]

Rabies is a zoonotic infectious disease caused by lyssavirus and characterized by central nervous system symptoms. The fatality rate of rabies is almost 100%. About 59 000 cases die of rabies worldwide every year, mainly in Asia and Africa. China is an epidemic country of rabies. Grade II and III exposures are the main types of rabies exposures in China. Standardized post-exposure prophylaxis (PEP) can prevent rabies almost 100%. Human Rabies Vaccine Technical Working Group, National Immunization Advisory Committee and invited experts reached an expert consensus on PEP by referring to the World Health Organization's position paper on rabies vaccine in 2018 and related research progress in recent.

[Reduced frequency of natural killer cell on siglec-7(+) is associated with progression of hepatitis B virus-related cirrhosis]

Objective: To explore the relationship between sialic-acid-binding immunoglobulin-like lectin 7 (Siglec-7) expressed on NK cells and hepatitis B virus-related cirrhosis. Methods: Peripheral venous blood samples were collected from 23 healthy controls and 31 patients with hepatitis B virus-related cirrhosis (Child-Pugh A, n = 7; Child-Pugh B, n = 12; Child-Pugh C, n = 12). Peripheral blood mononuclear cells (PBMCs) were obtained by using Ficoll-Hypaque density gradient centrifugation and the expression of Siglec-7 and NK cells phenotype and their subpopulations were detected by flow cytometry. Comparisons between various groups were performed using t -test, one-way analysis of variance (ANOVA), and correlations between variables were analyzed using Pearson's-correlation coefficient. Results: (1) There was no significant difference in the percentage of NK cells and in their subpopulations with HBV-related cirrhosis and healthy controls. (2) Siglec-7 expression on NK cells in patients with HBV-related cirrhosis(62.44±13.45%)was significantly down-regulated than that to healthy controls(75.39±12.19%)while the frequency of Siglec-7(+) NK cells were negatively correlated with Child-Pugh score. (3) Subpopulation analysis showed that Siglec-7 expression on CD56(bright)CD16(-)NK cells(66.99±15.93%)was significantly lower than CD56(dim)CD16(+)NK cells(76.54±13.9%) in HBV-related cirrhosis. However, the expression of Siglec-7 in healthy controls showed no difference in these two NK cell subsets. (4) Phenotypic analysis showed that Siglec-7(+) NK cells express higher levels of activating receptor CD16, CD38, NKp46 and lower levels of inhibitory receptor CD158b. Indeed, the frequency of CD16 and CD38 on Siglec-7(+) NK cells in HBV-related cirrhosis was lower than that in healthy controls. Conclusion: The disease progression in patients with hepatitis B virus-related cirrhosis is associated to decreased frequencies of Siglec-7(+)NK cells.

[Strategy for prevention and control of imported infectious disease]

The process of globalization increases the risk of global transmission of infectious diseases, resulting in pressure for country's prevention and control of imported infectious disease. Based on the risk assessment of disease importation and local transmission, a strategy that conducting importation prevention and routine prevention and control before the importation of disease and taking emergency control measures after the importation of disease was developed. In addition, it is important to take part in global infectious disease response action, aid the countries with outbreak or epidemic to actively decrease the risk of disease importation.

Epidemiological shift and geographical heterogeneity in the burden of leptospirosis in China

Background

Leptospirosis morbidity and mortality rates in China have decreased since the 2000s. Further analyses of the spatiotemporal and demographic changes occurring in the last decade and its implication on estimates of disease burden are required to inform intervention strategies. In this study, we quantified the epidemiological shift and geographical heterogeneity in the burden of leptospirosis during 2005–2015 in China.

Methods

We used reported leptospirosis case data from 1st January 2005 to 31st of December 2015 that routinely collected by the China Information System for Disease Control and Prevention (CISDCP) to analyze the epidemiological trend and estimate the burden in terms of disability-adjusted life-years (DALYs) over space, time, and demographical groups.

Results

A total of 7763 cases were reported during 2005–2015. Of which, 2403 (31%) cases were the laboratory-confirmed case. Since 2005, the notified incidence rate was gradually decreased (P < 0.05) and it was relatively stable during 2011–2015 (P > 0.05). During 2005–2015, we estimated a total of 10 313 DALYs were lost due to leptospirosis comprising a total of 1804 years-lived with disability (YLDs) and 8509 years-life lost (YLLs). Males had the highest burden of disease (7149 DALYs) compared to females (3164 DALYs). The highest burden estimate was attributed to younger individuals aged 10–19 years who lived in southern provinces of China. During 2005–2015, this age group contributed to approximately 3078 DALYs corresponding to 30% of the total DALYs lost in China. Yet, our analysis indicated a declining trend in burden estimates (P < 0.001) since 2005 and remained relatively low during 2011–2015. Low burden estimates have been identified in the endemic regions where infections principally distributed. Most of the changes in DALY estimates were driven by changes in YLLs.

Conclusions

In the last 11-years, the burden estimates of leptospirosis have shown a declining trend across the country; however, leptospirosis should not be neglected as it remains an important zoonotic disease and potentially affecting the young and productive population in economically less-developed provinces in southern of China. In addition, while in the last five years the incidence has been reported at very low-level, this might not reflect the true incidence of leptospirosis. Strengthened surveillance in the endemic regions is, hence, substantially required to capture the actual prevalence to better control leptospirosis in China.

Electronic supplementary material

The online version of this article (10.1186/s40249-018-0435-2) contains supplementary material, which is available to authorized users.

[Analysis on the epidemiological features of human brucellosis in northern and southern areas of China, 2015-2016]

Different epidemiological features of human brucellosis appeared in both northern and southern areas of China. The disease was seen endemic in the northern and dispersal in the southern provinces. Appropriate strategies for brucellosis prevention and control should be developed, according to the different epidemiological characteristics in the northern or southern areas.

Genetic source tracking of an anthrax outbreak in Shaanxi province, China

Background

Anthrax is an acute zoonotic infectious disease caused by the bacterium known as Bacillus anthracis. From 26 July to 8 August 2015, an outbreak with 20 suspected cutaneous anthrax cases was reported in Ganquan County, Shaanxi province in China. The genetic source tracking analysis of the anthrax outbreak was performed by molecular epidemiological methods in this study.

Methods

Three molecular typing methods, namely canonical single nucleotide polymorphisms (canSNP), multiple-locus variable-number tandem repeat analysis (MLVA), and single nucleotide repeat (SNR) analysis, were used to investigate the possible source of transmission and identify the genetic relationship among the strains isolated from human cases and diseased animals during the outbreak.

Results

Five strains isolated from diseased mules were clustered together with patients’ isolates using canSNP typing and MLVA. The causative B. anthracis lineages in this outbreak belonged to the A.Br.001/002 canSNP subgroup and the MLVA15-31 genotype (the 31 genotype in MLVA15 scheme). Because nine isolates from another four provinces in China were clustered together with outbreak-related strains by the canSNP (A.Br.001/002 subgroup) and MLVA15 method (MLVA15-31 genotype), still another SNR analysis (CL10, CL12, CL33, and CL35) was used to source track the outbreak, and the results suggesting that these patients in the anthrax outbreak were probably infected by the same pathogen clone.

Conclusions

It was deduced that the anthrax outbreak occurred in Shaanxi province, China in 2015 was a local occurrence.

Electronic supplementary material

The online version of this article (doi:10.1186/s40249-016-0218-6) contains supplementary material, which is available to authorized users.

A practical community-based response strategy to interrupt Ebola transmission in sierra Leone, 2014-2015

Background

The Ebola virus disease spread rapidly in West Africa in 2014, leading to the loss of thousands of lives. Community engagement was one of the key strategies to interrupt Ebola transmission, and practical community level measures needed to be explored in the field and tailored to the specific context of communities.

Methods

First, community-level education on Ebola virus disease (EVD) prevention was launched for the community’s social mobilizers in six districts in Sierra Leone beginning in November 2014. Then, from January to May of 2015, in three pilot communities, local trained community members were organized to engage in implementation of EVD prevention and transmission interruption measures, by involving them in alert case report, contact tracing, and social mobilization. The epidemiological indicators of transmission interruption in three study communities were evaluated.

Results

A total of 6 016 community social mobilizers from 185 wards were trained by holding 279 workshops in the six districts, and EVD message reached an estimated 631 680 residents. In three pilot communities, 72 EVD alert cases were reported, with 70.8 % of them detected by trained local community members, and 14 EVD cases were finally identified. Contact tracing detected 64.3 % of EVD cases. The median duration of community infectivity for the cases was 1 day. The secondary attack rate was 4.2 %, and no third generation of infection was triggered. No health worker was infected, and no unsafe burial and noncompliance to EVD control measures were recorded. The community-based measures were modeled to reduce 77 EVD cases, and the EVD-free goal was achieved four months earlier in study communities than whole country of Sierra Leone.

Conclusions

The community-based strategy of social mobilization and community engagement was effective in case detection and reducing the extent of Ebola transmission in a country with weak health system. The successfully practical experience to reduce the risk of Ebola transmission in the community with poor resources would potentially be helpful for the global community to fight against the EVD and the other diseases in the future.

Electronic supplementary material

The online version of this article (doi:10.1186/s40249-016-0167-0) contains supplementary material, which is available to authorized users.

[Technical guideline for human rabies prevention and control (2016)]

In order to promote the prevention and control programs on rabies in our country, to regulate the prevention and disposition of rabies and to reduce the deaths caused by rabies, the Chinese Center for Disease Control and Prevention has organized a panel of experts, in the reference with Guidelines issued by WHO, American Advisory Committee on Immunization Practices, and the latest research progress from home and abroad, and compiled this document-"Technical Guidelines for Human Rabies Prevention and Control (2016)". The Guidelines conducted a systematic review on the etiology, clinical characteristics, laboratory diagnosis, epidemiology of rabies and provided evidence on varieties, mechanisms, effects, side-effects and security of rabies vaccine, as well as on other preparations on passive immunity of its kind, on methods related to prevention and disposition of exposure etc, finally to have come up with the recommendation on the above mentioned various techniques. The guidelines will be used by staff working on prevention and control of rabies from the Center for Disease Control and Prevention at all levels, from the departments of outpatient and divisions of infection and emergency control in all the medical institutions. The guideline will be updated and revised, following the research progress from home and abroad.

A national assessment of the epidemiology of severe fever with thrombocytopenia syndrome, China

First discovered in rural areas of middle-eastern China in 2009, severe fever with thrombocytopenia syndrome (SFTS) is an emerging tick-borne zoonosis affecting hundreds of cases reported in China each year. Using the national surveillance data from 2010 to 2013, we conducted this retrospective epidemiological study and risk assessment of SFTS in China. We found that the incidence of SFTS and its epidemic areas are continuing to grow, but the case fatality rate (CFR) has steadily decreased. SFTS most commonly affected elderly farmers who acquired infection between May and July in middle-eastern China. However, other epidemiological characteristics such as incidence, sex ratio, CFR, and seasonality differ substantially across the affected provinces, which seem to be consistent with local agricultural activities and the seasonal abundance of ticks. Spatial scan statistics detected three hot spots of SFTS that accounted for 69.1% of SFTS cases in China. There was a strong association of SFTS incidence with temporal changes in the climate within the clusters. Multivariate modeling identified climate conditions, elevation, forest coverage, cattle density, and the presence of Haemaphysalis longicornis ticks as independent risk factors in the distribution of SFTS, based on which a predicted risk map of the disease was derived.

Spatiotemporal transmission dynamics of hemorrhagic fever with renal syndrome in China, 2005-2012

Background

Hemorrhagic fever with renal syndrome (HFRS) is a rodent-borne disease caused by many serotypes of hantaviruses. In China, HFRS has been recognized as a severe public health problem with 90% of the total reported cases in the world. This study describes the spatiotemporal dynamics of HFRS cases in China and identifies the regions, time, and populations at highest risk, which could help the planning and implementation of key preventative measures.

Methods

Data on all reported HFRS cases at the county level from January 2005 to December 2012 were collected from Chinese Center for Disease Control and Prevention. Geographic Information System-based spatiotemporal analyses including Local Indicators of Spatial Association and Kulldorff's space-time scan statistic were performed to detect local high-risk space-time clusters of HFRS in China. In addition, cases from high-risk and low-risk counties were compared to identify significant demographic differences.

Results

A total of 100,868 cases were reported during 2005–2012 in mainland China. There were significant variations in the spatiotemporal dynamics of HFRS. HFRS cases occurred most frequently in June, November, and December. There was a significant positive spatial autocorrelation of HFRS incidence during the study periods, with Moran's I values ranging from 0.46 to 0.56 (P<0.05). Several distinct HFRS cluster areas were identified, mainly concentrated in northeastern, central, and eastern of China. Compared with cases from low-risk areas, a higher proportion of cases were younger, non-farmer, and floating residents in high-risk counties.

Conclusions

This study identified significant space-time clusters of HFRS in China during 2005–2012 indicating that preventative strategies for HFRS should be particularly focused on the northeastern, central, and eastern of China to achieve the most cost-effective outcomes.

Hemorrhagic fever with renal syndrome (HFRS) is a rodent-borne viral disease caused by many serotypes of hantaviruses. In China, HFRS has been recognized as a severe public health problem and accounts for 90% of the reported cases in the world. We examined the spatiotemporal dynamics of HFRS cases in China during 2005–2012 and compared characteristics between cases from high-risk and low-risk counties. Several distinct HFRS cluster areas were identified, concentrated in northeastern, central, and eastern of China. Compared with cases from low-risk areas, a higher proportion of cases were younger, non-farmer, and floating residents in high-risk counties. These findings suggest preventative strategies for HFRS should be focused on the identified clusters in order to achieve the most cost-effective outcomes.

Risk factors for bunyavirus-associated severe Fever with thrombocytopenia syndrome, china

Background

Severe fever with thrombocytopenia syndrome (SFTS) is an emerging disease that is caused by a novel bunyavirus, referred to as SFTS virus. During January 2011 to December 2011 we conducted a case-control study in Henan, Hubei and Shandong Provinces of China to determine the risk factors for SFTS.

Methods

Case-patients were identified in hospitals and reported to provincial Centers for Disease Control and Prevention while being notified electronically to the National Surveillance System. Controls were randomly selected from a pool of patients admitted to the same hospital ward within one week of the inclusion of the cases. They were matched by age (+/−5 years) and gender.

Results

A total of 422 patients participated in the study including 134 cases and 288 matched controls. The median age of the cases was 58.8 years, ranging from 47.6 to 70.1 years; 54.5% were male. No differences in demographics were observed between cases and controls; however, farmers were frequent and more common among cases (88.8%) than controls (58.7%). In multivariate analysis, the odds for SFTS was 2.4∼4.5 fold higher with patients who reported tick bites or presence of tick in the living area. Other independent risk factors included cat or cattle ownership and reported presence of weeds and shrubs in the working environment.

Conclusions

Our findings support the hypothesis that ticks are important vectors of SFTS virus. Further investigations are warranted to understand the detailed modes of transmission of SFTS virus while vector management, education on tick bites prevention and personal hygiene management should be implemented for high-risk groups in high incidence areas.

Since 2009, an emerging infectious disease which was identified as the severe fever with thrombocytopenia syndrome (SFTS) was reported in rural areas of Hubei, Shandong and Henan provinces in China. A novel bunyavirus designated severe fever with thrombocytopenia syndrome bunyavirus (SFTSV) had been identified to be the etiological cause of SFTS. But what risk factors lead to the disease is still not clear. Further investigations for risk factors are needed to effectively prevent and control the disease. Here we have designed case-control study to try to develop the risk factors of the spread of SFTSV. It is hoped that our research could provide epidemiological evidence for further study. Also help to determine the spread of the virus in the environment.

Spatiotemporal patterns of Japanese encephalitis in China, 2002-2010

Objective

The aim of the study is to examine the spatiotemporal pattern of Japanese Encephalitis (JE) in mainland China during 2002–2010. Specific objectives of the study were to quantify the temporal variation in incidence of JE cases, to determine if clustering of JE cases exists, to detect high risk spatiotemporal clusters of JE cases and to provide evidence-based preventive suggestions to relevant stakeholders.

Methods

Monthly JE cases at the county level in mainland China during 2002–2010 were obtained from the China Information System for Diseases Control and Prevention (CISDCP). For the purpose of the analysis, JE case counts for nine years were aggregated into four temporal periods (2002; 2003–2005; 2006; and 2007–2010). Local Indicators of Spatial Association and spatial scan statistics were performed to detect and evaluate local high risk space-time clusters.

Results

JE incidence showed a decreasing trend from 2002 to 2005 but peaked in 2006, then fluctuated over the study period. Spatial cluster analysis detected high value clusters, mainly located in Southwestern China. Similarly, we identified a primary spatiotemporal cluster of JE in Southwestern China between July and August, with the geographical range of JE transmission increasing over the past years.

Conclusion

JE in China is geographically clustered and its spatial extent dynamically changed during the last nine years in mainland China. This indicates that risk factors for JE infection are likely to be spatially heterogeneous. The results may assist national and local health authorities in the development/refinement of a better preventive strategy and increase the effectiveness of public health interventions against JE transmission.

Japanese encephalitis (JE) is a mosquito-borne disease, which primarily occurs in rural and suburban areas of Southeast Asia and the Western Pacific region. JE still remains a significant public health problem in mainland China, with approximately 50% of global cases annually. Few studies have explored the spatiotemporal patterns of JE cases in China. Here we reported the results of Local Indicators of Spatial Association and spatial scan statistics of JE cases in mainland China at the county level during the four periods: 2002; 2003–2005; 2006; 2007–2010. The primary spatiotemporal cluster of JE was detected in Southwestern China between July and August, with the geographical range of JE transmission increasing over the past years. The results of LISA and spatial scan statistics were consistent which indicates that these methods are reliable and could have wider applications in the fields of disease surveillance and management in China, particularly in the surveillance and monitoring of other vector-borne diseases. These findings may assist in informing prevention and control strategies and increase the effectiveness of public health interventions against JE transmission.

[The current epidemic situation and surveillance regarding hemorrhagic fever with renal syndrome in China, 2010]

OBJECTIVE

To analyze the surveillance data on hemorrhagic fever with renal syndrome (HFRS) including the epidemiological characteristics and trend of the disease, in 2010.

METHODS

Descriptive methods were conducted to analyze the surveillance data in 2010 which were collected from the internet-based National Notifiable Disease Reporting System and 40 HFRS sentinels in China.

RESULTS

There were 9526 cases of HFRS reported in 2010 in the country with an annual morbidity of 0.71/10(5), which was higher than that reported in 2009. And the case fatality rate in 2010 was 1.24%. During the year 2010, most cases were reported in spring and autumn-winter season, with November as the peak month. The proportion of cases reported in autumn-winter season was higher than that in spring. The number of cases reported in males was higher than that in females among all the age groups, and similar pattern of mortality could be seen in most of the age groups. The percentage of cases over 60 years old had increased in recent years. Farmers were still under the highest risk. Density and the virus-carrying rate of animal hosts, as well as the infection rate were relatively stable and similar to the previous findings. As to the prevailing species, Apodemus agrarius and Rattus norvegicus were still the most common and leading animal hosts. However, the dominant species in sentinel of Yunnan were Rattus flavipectus and Eothenomys miletus respectively, and a new hantavirus called LUXV was found, namely Eothenomys miletus.

CONCLUSION

HFRS cases were widely distributed in most provinces of China, but cases mainly focus on certain areas and present the nature of aggregation. The risk of outbreak could not be ruled out for variety of factors. Population characteristics and seasonal fluctuation had been changing.

[Epidemiological analysis of rabies in 2010, China]

OBJECTIVE

To understand the related factors of rabies epidemic and provide the basic data for rabies control and prevention in China by statistic and retrospective analysis of rabies surveillance data in 2010.

METHODS

We used descriptive epidemiology method and statistic analysis to analyze the epidemiological characteristics of rabies in 2010 of China.

RESULTS

2048 rabies cases were rabies cases were reported in 817 counties (districts) in 2010, which dropped 7.46% compares to 2009. The incidences in children and elder people were high; farmers are main occupation of the cases, the male to female ratio of the cases was 2.44:1. Children and older people are higher acquired rabies than other age population. 640 cases reported through national rabies sentinel surveillance system, 87.50% cases were caused by exposed to dogs, bite was the main exposure reason. The situation of deposing wounds was poor, and the use of vaccine was still low in individual cases, but in the rabies clinic cases under surveillance, the vaccine usage can reach 98%, the usage of immunoglobulin (RIG) or anti-serum for category III exposure in either group cases was not high.

CONCLUSION

The epidemic of the rabies in 2010 was eased, Out-patient post-exposure prophylaxis was in good station, but there are still lots of problem existed: post-exposure prophylaxis of individual case was not desirable yet.

Fever with thrombocytopenia associated with a novel bunyavirus in China

BACKGROUND

Heightened surveillance of acute febrile illness in China since 2009 has led to the identification of a severe fever with thrombocytopenia syndrome (SFTS) with an unknown cause. Infection with Anaplasma phagocytophilum has been suggested as a cause, but the pathogen has not been detected in most patients on laboratory testing.

METHODS

We obtained blood samples from patients with the case definition of SFTS in six provinces in China. The blood samples were used to isolate the causal pathogen by inoculation of cell culture and for detection of viral RNA on polymerase-chain-reaction assay. The pathogen was characterized on electron microscopy and nucleic acid sequencing. We used enzyme-linked immunosorbent assay, indirect immunofluorescence assay, and neutralization testing to analyze the level of virus-specific antibody in patients' serum samples.

RESULTS

We isolated a novel virus, designated SFTS bunyavirus, from patients who presented with fever, thrombocytopenia, leukocytopenia, and multiorgan dysfunction. RNA sequence analysis revealed that the virus was a newly identified member of the genus phlebovirus in the Bunyaviridae family. Electron-microscopical examination revealed virions with the morphologic characteristics of a bunyavirus. The presence of the virus was confirmed in 171 patients with SFTS from six provinces by detection of viral RNA, specific antibodies to the virus in blood, or both. Serologic assays showed a virus-specific immune response in all 35 pairs of serum samples collected from patients during the acute and convalescent phases of the illness.

CONCLUSIONS

A novel phlebovirus was identified in patients with a life-threatening illness associated with fever and thrombocytopenia in China. (Funded by the China Mega-Project for Infectious Diseases and others.).

[Self-management behaviors among children after exposure to rabies in two severe rabies epidemic areas of China]

OBJECTIVE

To understand the situation of rabies exposure and self-management behaviors among primary school students from rabies epidemic areas in China.

METHODS

This population-based investigation was conducted in Guizhou and Guangdong provinces which had been severe epidemic areas of rabies in China from January 2007 to May 2008. Primary schools from two prefectural, two county, four township and four village levels were selected in the 2 provinces. Students were sampled from each grade of the 12 schools to collect information on post-exposure prophylaxis.

RESULTS

In the 2408 primary school students interviewed, 290 person/times exposure were found from 2007 to 2008. The self wound-treatment rates was 47.93%, with 16.55% of them went to the clinic for care-seeking initiatively and 63.79% informed their parents or teachers. However 23.10% of the students did nothing after exposure. Students in Guangdong province had lower exposure rate and higher rate of good management behaviors than in Guizhou. No significant statistical difference was found between the self-management behaviors among male and female students or among different levels of primary schools. The proportion of disinfection on wounds with alcohol and seeking medical treatment in rabies clinic initiatively were both low in all grades of the students but the proportion of telling their parents or teachers about the exposure among children was high in all grades of students.

CONCLUSION

Some students after rabies exposure did not have any disposal in Guangdong and Guizhou provinces. Related education should be strengthened.

[Current situation and surveillance on dengue fever in China, 2005 - 2007]

OBJECTIVE

To provide scientific evidence for prevention and control program on dengue fever through analyzing the situation of dengue fever in China, from 2005 to 2007.

METHODS

Data was collected from Internet-based National Notifiable Infectious Disease Reporting System, National Enhanced Dengue Fever Surveillance System and field investigation on dengue outbreaks, described and analyzed with descriptively and by SPSS statistical software.

RESULTS

There was a total number of 1623 dengue cases (including 1356 laboratory confirmed cases and 267 probable cases) and 1 death case reported in China from 2005 to 2007. Among the identified cases, 151 were imported from foreign countries as the Southeast Asian countries, accounting for 9.3%, while the rest 1472 cases were reported from local infections, identified only in 9 cities from Guangdong and Fujian provinces. Data from the monitoring program on Aedes Mosquitoes indicated that: The indicators of BI from 84.6% of the sentinels were over 5, and BI from 72.2% of the sentinels were over 10. This index was especially at a higher level during summer in the southern areas of China. Aedes albopictus was found in all the sentinel sites while Aedes aegypti was only found in Hainan and in limited counties of Guangdong. No dengue virus was isolated from mosquito vectors collected from national sentinel sites, whereas positive results had been detected by PCR test in Guangdong province.

CONCLUSION

It was assumed that a sustainable local circulation of dengue virus had not yet been established successfully in Mainland China according to the surveillance data. However, more local outbreaks reported in Guangdong and Fujian with the wide distribution and high-level density of aedes mosquito, low antibody level in healthy population and the increasing number of imported dengue cases, there is a potential of Dengue outbreaks in southern China. An integrated mosquito vector monitoring and management system is needed in high risk area to reduce the transmission of dengue fever.

Experimental evaluation of a hyperbolic ion trap for fourier transform ion cyclotron resonance mass spectrometry

The Penning ion trap, consisting of hyperbolically curved electrodes arranged as an unbroken ring electrode capped by two end electrodes whose interelectrode axis lies along the direction of an applied static magnetic field, has long been used for single-ion trapping. More recently, it has been used in "parametric" mode for ion cyclotron resonance (lCR) detection of off-axis ions. In this article, we describe and test a Penning trap whose ring electrode has been cut into four equal quadrants for conventional dipolar ICR excitation (on one pair of opposed ring quadrants) and dipolar ICR detection (on the other pair). In direct comparisons to a cubic trap, the present hyperbolic trap offers somewhat improved ICR mass spectral peak shape, higher mass resolving power, and comparable frequency shift as a function of trapping voltage. Mass measurement accuracy over a wide mass range is improved twofold and mass discrimination is somewhat worse than for a cubic trap. The relative advantages of parametric, dipolar, and quadrupole modes are briefly discussed in comparison to screened and unscreened cubic traps.