Brucellosis In China Research Articles

Brucellosis Seroprevalence in Cattle in China During 2014–2024: A Systematic Review and Meta-analysis

Brucellosis, caused by several species of Brucella, continues to be a significant illness that poses a global threat to public health. China remains a persistent hotspot for brucellosis, despite the implementation of extensive control measures. This study aims to conduct a systematic review and meta-analysis of the seroprevalence of bovine brucellosis in different breeds and regions of China from 2014-2024, and to provide predictions on the future prevalence patterns of brucellosis in cattle and humans. The analysis comprised a total of 80 research studies, which consisted of 187 datasets and a combined sample size of 3,130,706. We estimated the overall pooled seroprevalence of bovine brucellosis in China to be 1.5% (95% CI: 0.6-2.6%). Subgroup analysis revealed that the seroprevalence in dairy cattle was 3.1%, surpassing the seroprevalence in beef cattle (1.3%) and yak (1.5%). Regions that had authorized vaccination programs exhibited higher seroprevalence (1.8%) compared to regions that did not have vaccination (0.5%). Notably, the study observed a simultaneous rise in both the prevalence of brucellosis in cattle and the number of human brucellosis cases. This suggests that high-quality routine surveillance of brucellosis in cattle will be essential for predicting and responding to cases in humans. Additionally, given the existing prevention and control measures, brucellosis will likely continue to be prevalent in both cattle and people. This systematic review will assist policymakers in adjusting animal surveillance and interregional livestock movement policies, ultimately contributing to the public safety goal of preventing brucellosis in humans by controlling it in animals.

Analysis of the Brucella melitensis epidemic in Xinjiang: genotyping, polymorphism, antibiotic resistance and tracing

Brucella spp. are facultative intracellular pathogens that cause zoonosis- brucellosis worldwide. There has been a trend of the re-emergence of brucellosis worldwide in recent years. The epidemic situation of brucellosis is serious in Xinjiang. To analyze the epidemic situation of Brucella spp. in Xinjiang among humans and animals, this study identified 144 Brucella isolates from Xinjiang using classical identification and 16 S rRNA sequencing. MLVA, drug resistance testing, and wgSNP detection were also performed. At the same time, analysis was conducted based on the published data of Brucella isolates worldwide. The results showed that the dominant species was B. melitensis biovar 3, which belonged to GT42 (MLVA-8 typing) and the East Mediterranean lineage. The correlation among isolates was high both in humans or animals. The isolates in Xinjiang exhibited higher polymorphism compared to other locations in China, with polymorphism increasing each year since 2010. No amikacin/kanamycin-resistant strains were detected, but six rifampicin-intermediate isolates were identified without rpoB gene variation. The NJ tree of the wgSNP results indicated that there were three main complexes of the B. melitensis epidemic in Xinjiang. Based on the results of this study, the prevention and control of brucellosis in Xinjiang should focus on B. melitensis, particularly strains belonging to B. melitensis bv.3 GT42 (MLVA-8 typing) and East Mediterranean lineage. Additionally, the rifampicin- and trimethoprim-sulfamethoxazole- resistance of isolates in Xinjiang should be closely monitored to avoid compromising the therapeutic efficacy and causing greater losses. These results provide essential data for the prevention and control of brucellosis in Xinjiang and China. Although the isolates from Xinjiang have significant characteristics among Chinese isolates and can reflect the epidemiological situation of brucellosis in China to some extent, this study cannot represent the characteristics of isolates from other regions.

Analysis on personal protection in occupational population at high risk for brucellosis and influencing factor in China

Objective: To understand the current status of personal protection in occupational population at high risk for brucellosis in China and provide evidence for the evaluation of implementation of National Brucellosis Prevention and Control Plan (2016-2020). Methods: Four counties in Shanxi Province and Xinjiang Uygur Autonomous Region were selected to conduct a questionnaire survey in occupational population at high risk for brucellosis from December 2019 to July 2020 by using cross-sectional survey methods. Results: A total of 2 384 persons at high risk for brucellosis were surveyed, and the standardized utilization rate of personal protective equipment (PPE) was 20.13% (480/2 384). The utilization rate of glove, mask, rubber shoe, and work cloth were 38.26% (912/2 384), 31.80% (758/2 384), 32.01% (763/2 384) and 30.87% (736/2 384),respectively. There were significant differences in the utilization rate and standardized utilization rate of the four types of PPE among populations in different age, occupation, educational level and area groups (all P<0.001). The utilization rate and standardized utilization rate of PPE were lower in people over 60 years old, women, farmers, and those with lower educational level. The results of multivariate analysis showed that occupation and area were the influencing factors for the standardized utilization of PPE, the standardized utilization rates of PPE were higher in herdsmen and veterinarians. The standardized utilization rate of PPE in Yanggao County and Huocheng County was significantly higher than that in Zuoyun County and Hunyuan County. Conclusions: The utilization rate of the four types of PPE in occupational population at high risk for brucellosis was not high in China, and the standardized utilization rate was low, lower than the requirement in National Brucellosis Prevention and Control Plan, and there were significant differences among different areas. It is urgent to distribute PPE to occupational population at high risk for brucellosis and carry out health education about PPE utilization. Meanwhile, it is necessary to strengthen information exchange or sharing among different areas.

The spatiotemporal trend of human brucellosis in China and driving factors using interpretability analysis

Human brucellosis has reemerged in China, with a distinct change in its geographical distribution. The incidence of human brucellosis has significantly risen in inland regions of China. To gain insights into epidemic characteristics and identify factors influencing the geographic spread of human brucellosis, our study utilized the Extreme Gradient Boosting (XGBoost) algorithm and interpretable machine learning techniques. The results showed a consistent upward trend in the incidence of human brucellosis, with a significant increase of 8.20% from 2004 to 2021 (95% CI: 1.70, 15.10). The northern region continued to face a serious human situation, with a gradual upward trend. Meanwhile, the western and southern regions have experienced a gradual spread of human brucellosis, encompassing all regions of China over the past decade. Further analysis using Shapley Additive Explanations (SHAP) demonstrated that higher Gross Domestic Product (GDP) per capita and increased funding for education have the potential to reduce the spread. Conversely, the expansion of human brucellosis showed a positive correlation with bed availability per 1000 individuals, humidity, railway mileage, and GDP. These findings strongly suggest that socioeconomic factors play a more significant role in the spread of human brucellosis than other factors.

Spatiotemporal dynamics and influencing factors of human brucellosis in Mainland China from 2005–2021

BackgroundBrucellosis poses a significant public health concern. This study explores the spatial and temporal dynamic evolution of human brucellosis in China and analyses the spatial heterogeneity of the influencing factors related to the incidence of human brucellosis at the provincial level.MethodsThe Join-point model, centre of gravity migration model and spatial autocorrelation analysis were employed to evaluate potential changes in the spatial and temporal distribution of human brucellosis in mainland China from 2005 to 2021. Ordinary Least Squares (OLS), Geographically Weighted Regression (GWR), and Multi-scale Geographically Weighted Regression (MGWR) models were constructed to analyze the spatial and temporal correlation between the incidence rate of human brucellosis and meteorological and social factors.ResultsFrom 2005 to 2021, human brucellosis in China showed a consistent upward trend. The incidence rate rose more rapidly in South, Central, and Southwest China, leading to a shift in the center of gravity from the North to the Southwest, as illustrated in the migration trajectory diagram. Strong spatial aggregation was observed. The MGWR model outperformed others. Spatio-temporal plots indicated that lower mean annual temperatures and increased beef, mutton, and milk production significantly correlated with higher brucellosis incidence. Cities like Guangxi and Guangdong were more affected by low temperatures, while Xinjiang and Tibet were influenced more by beef and milk production. Inner Mongolia and Heilongjiang were more affected by mutton production. Importantly, an increase in regional GDP and health expenditure exerted a notable protective effect against human brucellosis incidence.ConclusionsHuman brucellosis remains a pervasive challenge. Meteorological and social factors significantly influence its incidence in a spatiotemporally specific manner. Tailored prevention strategies should be region-specific, providing valuable insights for effective brucellosis control measures.

Socioeconomic, meteorological factors and spatiotemporal distribution of human brucellosis in China between 2004 and 2019-A study based on spatial panel model.

Human brucellosis continues to be a great threat to human health in China. The present study aimed to investigate the spatiotemporal distribution of human brucellosis in China from 2004 to 2019, to analyze the socioeconomic factors, meteorological factors and seasonal effect affecting human brucellosis incidence in different geographical regions with the help of spatial panel model, and to provide a scientific basis for local health authorities to improve the prevention of human brucellosis. The monthly reported number and incidence of human brucellosis in China from January 2004 to December 2019 were obtained from the Data Center for China Public Health Science. Monthly average air temperature and monthly average relative humidity of 31 provincial-level administrative units (22 provinces, 5 autonomous regions and 4 municipalities directly under the central government) in China from October 2003 to December 2019 were obtained from the National Meteorological Science Data Centre. The inventory of cattle, the inventory of sheep, beef yield, mutton yield, wool yield, milk yield and gross pastoral product of 31 provincial-level administrative units in China from 2004 to 2019 were obtained from the National Bureau of Statistics of China. The temporal and geographical distribution of human brucellosis was displayed with Microsoft Excel and ArcMap software. The spatial autocorrelation and hotspot analysis was used to describe the association among different areas. Spatial panel model was constructed to explore the combined effects on the incidence of human brucellosis in China. A total of 569,016 cases of human brucellosis were reported in the 31 provincial-level administrative units in China from January 2004 to December 2019. Human brucellosis cases were concentrated between March and July, with a peak in May, showing a clear seasonal increase. The incidence of human brucellosis in China from 2004 to 2019 showed significant spatial correlations, and hotspot analysis indicated that the high incidence of human brucellosis was mainly in the northern China, particularly in Inner Mongolia, Shanxi, and Heilongjiang. The results from spatial panel model suggested that the inventory of cattle, the inventory of sheep, beef yield, mutton yield, wool yield, milk yield, gross pastoral product, average air temperature (the same month, 2-month lagged and 3-month lagged), average relative humidity (the same month) and season variability were significantly associated with human brucellosis incidence in China. The epidemic area of human brucellosis in China has been expanding and the spatial clustering has been observed. Inner Mongolia and adjacent provinces or autonomous regions are the high-risk areas of human brucellosis. The inventory of cattle and sheep, beef yield, mutton yield, wool yield, milk yield, gross pastoral product, average air temperature, average relative humidity and season variability played a significant role in the progression of human brucellosis. The present study strengthens the understanding of the relationship between socioeconomic, meteorological factors and the spatial heterogeneity of human brucellosis in China, through which 'One Health'-based strategies and countermeasures can be provided for the government to tackle the brucellosis menace.

Driving role of climatic and socioenvironmental factors on human brucellosis in China: machine-learning-based predictive analyses

BackgroundBrucellosis is a common zoonotic infectious disease in China. This study aimed to investigate the incidence trends of brucellosis in China, construct an optimal prediction model, and analyze the driving role of climatic factors for human brucellosis.MethodsUsing brucellosis incidence, and the socioeconomic and climatic data for 2014–2020 in China, we performed spatiotemporal analyses and calculated correlations with brucellosis incidence in China, developed and compared a series of regression and Seasonal Autoregressive Integrated Moving Average X (SARIMAX) models for brucellosis prediction based on socioeconomic and climatic data, and analyzed the relationship between extreme weather conditions and brucellosis incidence using copula models.ResultsIn total, 327,456 brucellosis cases were reported in China in 2014–2020 (monthly average of 3898 cases). The incidence of brucellosis was distinctly seasonal, with a high incidence in spring and summer and an average annual peak in May. The incidence rate was highest in the northern regions’ arid and continental climatic zones (1.88 and 0.47 per million people, respectively) and lowest in the tropics (0.003 per million people). The incidence of brucellosis showed opposite trends of decrease and increase in northern and southern China, respectively, with an overall severe epidemic in northern China. Most regression models using socioeconomic and climatic data cannot predict brucellosis incidence. The SARIMAX model was suitable for brucellosis prediction. There were significant negative correlations between the proportion of extreme weather values for both high sunshine and high humidity and the incidence of brucellosis as follows: high sunshine, r = −0.59 and −0.69 in arid and temperate zones; high humidity, r = −0.62, −0.64, and −0.65 in arid, temperate, and tropical zones.ConclusionsSignificant seasonal and climatic zone differences were observed for brucellosis incidence in China. Sunlight, humidity, and wind speed significantly influenced brucellosis. The SARIMAX model performed better for brucellosis prediction than did the regression model. Notably, high sunshine and humidity values in extreme weather conditions negatively affect brucellosis. Brucellosis should be managed according to the “One Health” concept.

Clearance of bacteria from lymph nodes in sheep immunized with Brucella suis S2 vaccine is associated with M1 macrophage activation

Ovine brucellosis is a global zoonotic disease of sheep caused by Brucella melitensis, which inflicts a significant burden on human and animal health. Brucella suis strain S2 (B. suis S2) is a smooth live attenuated vaccine for the prevention of ovine brucellosis in China. However, no previous studies have assessed the immunogenicity of B. suis S2 vaccine after oral immunization in sheep. Here, we attempted to evaluate the ovine immune response over the course of B. suis S2 immunization and to identify in vivo predictors for vaccine development. Body temperature, serum Brucella antibodies, serum cytokines (IL-12p70 and interferon [IFN]-γ), and bacterial load in the mandibular lymph nodes (LN), superficial cervical LN, superficial inguinal LN, and spleen were investigated to determine the safety and efficacy of the vaccine. The abnormal body temperature of sheep occurred within 8 days post-infection (dpi). Brucella suis S2 persisted for a short time (< 21 dpi) in the mandibular LN. The highest level of IL-12p70 was observed at 9 dpi, whereas serum IFN-γ levels peaked at 12 dpi. Transcriptome analysis and quantitative reverse transcription PCR were performed to determine gene expression profiles in the mandibular LN of sheep. Antigen processing and presentation pathway was the dominant pathway related to the dataset. Our studies suggest that the immune response in ovine LN resembled type 1 immunity with the secretion of IL-12p70 and IFN-γ after B.suis S2 immunization and the vaccine may eliminate Brucella via stimulation of M1 macrophages through the course of Th cells.

Epidemic Characteristics, High-Risk Areas and Space-Time Clusters of Human Brucellosis - China, 2020-2021.

Analyze the recent epidemiological and temporal-spatial characteristics of human brucellosis in China and provide information for adjusting strategies for brucellosis control. Human brucellosis data were obtained from the National Notifiable Disease Reporting System (NNDRS). A geographical information system (GIS) was used to visualize high-risk areas with annual incidence based on county (district) polygons. The space-time scan statistic (STSS) was applied to detect the space-time clusters of human brucellosis. A total of 69,767 cases were reported from 2,083 counties in the mainland of China in 2021, a 47.7% increase from 2020 (47,425). About 95.5% of the total cases were centralized in northern China and 31.8% in Inner Mongolia (IM). The number of counties with an incidence exceeding 100 per 100,000 was 34 in 2020 and 65 in 2021. From 2020 to 2021, 24 space-time clusters were detected. The two primary clusters were located northeast of IM, including 109 counties. The secondary clusters affected 208 counties in 2020 and spread to 297 counties in 2021, the majority of which were located in the middle of IM, exhibiting a trend spreading west from IM to neighboring provincial-level administrative divisions (PLADs). From 2020 to 2021, the incidence of human brucellosis nationwide was exponential, demonstrating distinct spatiotemporal characteristics. Space-time clusters were located in IM and neighboring areas. Therefore, considerable efforts are required to curb this momentum.

Interactions of periodic birth and shearing induce outbreak of Brucellosis in Inner Mongolia

Brucellosis, a zoonotic disease, has brought about enormous human suffering and tremendous economic burden to animal husbandry in China. However, Inner Mongolia is the hardest hit area of brucellosis in China. A total of 132,037 human cases have been reported from 2010 to 2020. Endogenous mechanisms of brucellosis spreading across Inner Mongolia till remains to be revealed. We propose a periodic epidemic model to investigate the effect of periodic parameter changes on brucellosis epidemics. Then we evaluate the basic reproduction number [Formula: see text] and analyze the global dynamics of the model. Furthermore, key parameters related to periodic transmission are estimated based on the monthly data of human brucellosis cases and the trend of newly infected human brucellosis cases are predicted in Inner Mongolia. Our modeling results illustrate that periodical birth and sheep shearing play a significant role in inducing periodical outbreak of brucellosis in Inner Mongolia. Moreover, it is exhibited that the annual peak number and the final scale of human brucellosis cases will be reduced dramatically with the delayed peak time of sheep birth. While the annual peak time will be lagged and the annual peak number will be decreased as the peak time of sheep shearing is postponed. In addition, we discover that it is difficult to stem brucellosis even if all sheep are vaccinated besides ewes. Nevertheless, the detection rate exceed a certain value 0.032 or the decaying rate of Brucella surpass a critical value 0.585, the human brucellosis can be regulated in Inner Mongolia according to the sensitivity analysis of [Formula: see text]. The insights shed herein may contribute to the careful implementation of brucellosis control strategies in other regions.

Aortic Pseudoaneurysm: Tumor? Igg Related Disorder? Infection?

A 67-year-old man presented with 5-month fatigue and weight loss. He also had constipation and persistent abdominal pain two weeks before hospitalization. A blood test showed an ESR of 34mm/ hour, CRP of 36.8mg/L, and a white cell count of 3600/mm3 with 84.3% neutrophils. A decreased density mass wrapping the lower abdominal aorta on the left was noticed by enhanced CT scan, 42*27mm in size with uneven enhancement (Panel A). Two weeks later, the mass aggressively developed into a size of 43*56mm with an aneurysmal protrusion (Panel B). He was suspected of IgG4 related disorder, tumors such as sarcoma, and infection [1-3]. Tracing back his history, he used to work on the farm of Inner Mongolia, where is the endemic area for human brucellosis in China [4]. Finally, brucellosis infection was confirmed by serology, sample smear microscopy, fluid culture, and metagenomics sequencing after a CT guided puncture. Now the patient was discharged with a prescription of 6-week antibiotics and waiting for further assessments. Human brucellosis has a broad spectrum of clinical manifestations, which ranges from subclinical infection to a full-blown clinical picture with an emphasis on muscular pain and night sweats [3]. Aorta wrapping brucellosis mass is a very rare complication [5,6] (Figure 1).

Evaluation and Differential Diagnosis of a Genetic Marked Brucella Vaccine A19ΔvirB12 for Cattle.

Brucella abortus is an important zoonotic pathogen that causes severe economic loss to husbandry and poses a threat to human health. The B. abortus A19 live vaccine has been extensively used to prevent bovine brucellosis in China. However, it is difficult to distinguish the serological response induced by A19 from that induced by natural infection. In this study, a novel genetically marked vaccine, A19ΔvirB12, was generated and evaluated. The results indicated that A19ΔvirB12 was able to provide effective protection against B. abortus 2308 (S2308) challenge in mice. Furthermore, the safety and protective efficacy of A19ΔvirB12 have been confirmed in natural host cattle. Additionally, the VirB12 protein allowed for serological differentiation between the S2308 challenge/natural infection and A19ΔvirB12 vaccination. However, previous studies have found that the accuracy of the serological detection based on VirB12 needs to be improved. Therefore, we attempted to identify potential supplementary antigens with differential diagnostic functions by combining label-free quantitative proteomics and protein chip technology. Twenty-six proteins identified only in S2308 were screened; among them, five proteins were considered as potential supplementary antigens. Thus, the accuracy of the differential diagnosis between A19ΔvirB12 immunization and field infection may be improved through multi-antigen detection. In addition, we explored the possible attenuation factors of Brucella vaccine strain. Nine virulence factors were downregulated in A19ΔvirB12. The downregulation pathways of A19ΔvirB12 were significantly enriched in quorum sensing, ATP-binding cassette transporter, and metabolism. Several proteins related to cell division were significantly downregulated, while some proteins involved in transcription were upregulated in S2308. In conclusion, our results contribute to the control and eradication of brucellosis and provide insights into the mechanisms underlying the attenuation of A19ΔvirB12.

Fluorescence polarization assay improves the rapid detection of human brucellosis in China

BackgroundBrucellosis is an infectious-allergic zoonotic disease caused by bacteria of the genus Brucella. Early diagnosis is the key to preventing, treating, and controlling brucellosis. Fluorescence polarization immunoassay (FPA) is a new immunoassay for relatively rapid and accurate detection of antibodies or antigens based on antigen–antibody interaction. However, there is no report on FPA-based detection of human brucellosis in China. Therefore, this study is to evaluate the value of FPA for the diagnosis of human brucellosis in China.MethodsWe recruited 320 suspected brucellosis cases who had the clinical symptoms and epidemiological risk factors between January and December, 2019. According to China Guideline for Human Brucellosis Diagnosis, the Rose Bengal test (RBT) was used for the screening test, and the serum agglutination test (SAT) was used as the confirmatory test. Brucellosis was confirmed only if the results of both tests were positive. Additionally, FPA and enzyme linked immune sorbent assay (ELISA) were compared with SAT, and their sensitivity, specificity, coincidence rate and consistency coefficient (Kappa value) as diagnostic tests were analyzed individually and in combination. The optimal cut-off value of FPA was also determined using the receiver operator characteristic (ROC) curve.ResultsThe optimum cut-off value of FPA was determined to be 88.5 millipolarization (mP) units, with a sensitivity of 94.5% and specificity of 100.0%. Additionally, the coincidence rate with the SAT test was 96.6%, and the Kappa value (0.9) showed excellent consistency. The sensitivity and specificity of FPA and ELISA combined were higher at 98.0% and 100.0% respectively.ConclusionsWhen the cut-off value of FPA test is set at 88.5 mP, it has high value for the diagnosis of brucellosis. Additionally, when FPA and ELISA are combined, the sensitivity of diagnosis is significantly improved. Thus, FPA may have potential in the future as a diagnostic method for human brucellosis in China.Graphic abstract

Characteristics of Brucella abortus vaccine strain A19 reveals its potential mechanism of attenuated virulence

Brucella vaccination is one of the most important strategies for controlling brucellosis in livestock. The A19 strain was the effective vaccine used to control brucellosis in China. However, the characteristics of physiological and attenuated virulence of the A19 strain are not investigated in detail. In this study, we compared the phenotypic characteristics of the A19 to the wild-type strain S2308. Virulence test showed that the A19 was significantly attenuated at chronic infection stage in infected mouse model. In growth analysis, the A19 exhibited a quick growth at exponential phase and premature at stationary phase. The inflammatory response of macrophages infected by the A19 was detected using TaqMan qPCR assay, indicating that the inflammatory level of the A19-infected macrophages was higher than that of the S2308 infection. Cell death analysis showed that the A19 was not cytotoxic for macrophages. Cell infection showed that the A19 reduced its ability to invade, survive and traffic within host cells, and the intracellular A19 hardly excludes lysosome-associated marker LAMP-1, suggesting that the A19 can’t escape the lysosome degradation within host cells. In further study, the sensitivity test exhibited that the A19 is more sensitive to stress and bactericidal factors than the S2308 strain, Western blot and silver staining analysis exhibited that the A19 has a different expression pattern of OMPs and reduces LPS O-antigen expression relative to the S2308 strain. Those data give us a more detailed understanding about the A19 vaccine strain, which will be beneficial for improvement of current Brucella vaccine and overcoming its defects.

Application and thinking of diagnostic methods of brucellosis in China

Brucellosis is a global public health problem, and the research on its diagnostic methods is still one of the hot fields. This article compares the diagnostic criteria of brucellosis of China, the United States and World Health Organization. The main detection methods of brucellosis in China and the current progress of molecular biological detection are described,and the characteristics of different diagnostic methods are compared. Although a relatively complete diagnostic system has been established in China, up to now, there is still no simple and rapid detection method with high sensitivity and specificity, indicating that further studies are needed to provide scientific evidence for the improvement of the diagnosis criteria of brucellosis in China.

Human distribution and spatial-temporal clustering analysis of human brucellosis in China from 2012 to 2016

BackgroundBrucellosis is a major public health issue in China, while its temporal and spatial distribution have not been studied in depth. This study aims to better understand the epidemiology of brucellosis in the mainland of China, by investigating the human, temporal and spatial distribution and clustering characteristics of the disease.MethodsHuman brucellosis data from the mainland of China between 2012 and 2016 were obtained from the China Information System for Disease Control and Prevention. The spatial autocorrelation analysis of ArcGIS10.6 and the spatial-temporal scanning analysis of SaTScan software were used to identify potential changes in the spatial and temporal distribution of human brucellosis in the mainland of China during the study period.ResultsA total of 244 348 human brucellosis cases were reported during the study period of 2012–2016. The average incidence of human brucellosis was higher in the 40–65 age group. The temporal clustering analysis showed that the high incidence of brucellosis occurred between March and July. The spatial clustering analysis showed that the location of brucellosis clustering in the mainland of China remained relatively fixed, mainly concentrated in most parts of northern China. The results of the spatial-temporal clustering analysis showed that Heilongjiang represents a primary clustering area, and the Tibet, Shanxi and Hubei provinces represent three secondary clustering areas.ConclusionsHuman brucellosis remains a widespread challenge, particularly in northern China. The clustering analysis highlights potential high-risk human groups, time frames and areas, which may require special plans and resources to monitor and control the disease.

Current status, progress and suggestions regarding prevention and control of brucellosis in China

Brucellosis is a neglected zoonosis, which not only endangers health of the people but also affects the development of animal husbandry, tourism and international trade as well as food safety. In the past two decades, great progress has been achieved in the prevention and control of both human and animal brucellosis, however, tremendous challenges still exists in the control and eradication of brucellosis, especially in the developing countries. In recent years, along with the increase of livestock breeding and animal or related product trade, human contacts with livestock has increased, resulting in the expansion of brucellosis endemic areas. In China, the brucellosis endemic areas are mainly distributed in Inner Mongolia and adjacent provinces, which might be explained by a lot of reasons, such as the development of animal husbandry, emerging and re-emerging of brucellosis endemic area and the movement of infection sources and degree of paid-attention. This paper summarizes the current status and progress in brucellosis prevention/control and surveillance in China and puts forward suggestions for the future improvement.

Optimization of Precontrol Methods and Analysis of a Dynamic Model for Brucellosis: Model Development and Validation.

BackgroundBrucella is a gram-negative, nonmotile bacterium without a capsule. The infection scope of Brucella is wide. The major source of infection is mammals such as cattle, sheep, goats, pigs, and dogs. Currently, human beings do not transmit Brucella to each other. When humans eat Brucella-contaminated food or contact animals or animal secretions and excretions infected with Brucella, they may develop brucellosis. Although brucellosis does not originate in humans, its diagnosis and cure are very difficult; thus, it has a huge impact on humans. Even with the rapid development of medical science, brucellosis is still a major problem for Chinese people. Currently, the number of patients with brucellosis in China is 100,000 per year. In addition, due to the ongoing improvement in the living standards of Chinese people, the demand for meat products has gradually increased, and increased meat transactions have greatly promoted the spread of brucellosis. Therefore, many researchers are concerned with investigating the transmission of Brucella as well as the diagnosis and treatment of brucellosis. Mathematical models have become an important tool for the study of infectious diseases. Mathematical models can reflect the spread of infectious diseases and be used to study the effect of different inhibition methods on infectious diseases. The effect of control measures to obtain effective suppression can provide theoretical support for the suppression of infectious diseases. Therefore, it is the objective of this study to build a suitable mathematical model for brucellosis infection.ObjectiveWe aimed to study the optimized precontrol methods of brucellosis using a dynamic threshold–based microcomputer model and to provide critical theoretical support for the prevention and control of brucellosis.MethodsBy studying the transmission characteristics of Brucella and building a Brucella transmission model, the precontrol methods were designed and presented to the key populations (Brucella-susceptible populations). We investigated the utilization of protective tools by the key populations before and after precontrol methods.ResultsAn improvement in the amount of glove-wearing was evident and significant (P<.001), increasing from 51.01% before the precontrol methods to 66.22% after the precontrol methods, an increase of 15.21%. However, the amount of hat-wearing did not improve significantly (P=.95). Hat-wearing among the key populations increased from 57.3% before the precontrol methods to 58.6% after the precontrol methods, an increase of 1.3%.ConclusionsBy demonstrating the optimized precontrol methods for a brucellosis model built on a dynamic threshold–based microcomputer model, this study provides theoretical support for the suppression of Brucella and the improved usage of protective measures by key populations.

The spatiotemporal distribution of human brucellosis in mainland China from 2007-2016

BackgroundDespite the considerable efforts made to address the issue of brucellosis worldwide, its prevalence in dairy products continues to be difficult to estimate and represents a key public health issue around the world today. The aim of the present study was to better understand the epidemiology of this disease in mainland China. We set out to investigate the yearly spatial distribution and possible hotspots of the disease.MethodsHuman brucellosis data from mainland China between 2007 and 2016 were collected from the China Information System for Disease Control and Prevention. A geographic information system ArcGIS10.3 (ESRI, Redlands) was used to identify potential changes in the spatial and temporal distribution of human brucellosis in mainland China during the study period. These distributions were evaluated using three-dimensional trend analysis and spatial autocorrelation analyse. A gravity-center was used to analyse the migration track of human brucellosis.ResultsA total of 399,578 cases of human brucellosis were reported during the 10-year study period. The monthly incidence of brucellosis in China demonstrates clear seasonality. Spring and summer are the peak seasons, while May is the peak month for brucellosis. Three-dimensional trend analysis suggests that brucellosis is on the rise from south to north, and that the epidemic situation in northern China is more severe. Between 2007 and 2016, the overall migration distance of the brucellosis incidence gravity-center was 906.43 km, and the direction was southwest. However, the overall gravity center of brucellosis was still in the northern part of China. In the global autocorrelation analysis, brucellosis in China demonstrated a non-random distribution between 2013 and 2014, with spatial autocorrelation (Z > 1.96, P < 0.05) and a clustering trend, while no clustering trend was found from 2007 to 2012 or from 2015 to 2016. In the local autocorrelation analysis, a Low-Low cluster phenomenon was found in the south of China in 2013 and 2014.ConclusionHuman brucellosis remains a widespread challenge, particularly in northern China. The hotspots highlight potential high-risk areas which may require special plans and resources for monitoring and controlling the disease.

Analysis on duplicated reporting of brucellosis in China, 2005-2017

Objective: To analyze the current status of duplicated reporting of brucellosis in China during 2005-2017, to understand the impact of duplicated reporting on the incidence of brucellosis, analyze the possible causes of duplicated reporting, and put forward propose solutions to further improve the brucellosis surveillance data quality. Methods: Data were from brucellosis case reporting cards in National Notifiable Disease Report System (NNDRS), Excel 2010 software was used to establish the database, the duplicated reporting was identified by using Spark DataFrame aggregation analysis in Python 3.2. Results: During 2005-2017, a total of 499 577 cases of brucellosis were reported, but the duplicated reporting rate was 75.76/10 000 (3 785/499 577). The duplicated reporting rate in same year was 37.21/10 000 (1 859/499 577), the duplicated reporting rate in other year was 39.87/10 000 (1 992/499 577) and the overall duplicated reporting rate increased year by year. The duplicated reporting rate in same institution was 33.59% (1 271/3 785) and the duplicated reporting rate by other institutions was 66.41% (2 514/3 785). Hospitals had the highest number of duplicated reporting (2 757), and community healthcare centers had the highest of duplicated reporting rate (281.27/10 000) (123/4 373). The reported incidence of brucellosis was 2.926 4/100 000 in 2017, the corrected incidence was 2.844 8/100 000 after removing the duplicated reporting, which was the maximum decrease from 2005 to 2017, the corrected incidence decreased by 2.79%. From 2005 to 2017, the average reported incidence of brucellosis in Xinjiang Uygur autonomous region was 14.712 0/100 000, and the corrected incidence was 14.060 0/100 000 after removing the duplicate reporting, with a decrease by 4.43%, the biggest decline in China. The average reported incidence of brucellosis in Ningxia Hui autonomous region was 13.987 1/100 000, and the corrected incidence of brucellosis was 13.662 2/100 000, with a decrease of 2.32%, ranking second in China. The reasons for duplicated reporting of brucellosis included repeated medical care seeking in same or different medical institutions in same year or other year, including the repeated medical care seeking in other areas. Conclusions: During 2005-2017, the number of duplicated reporting of brucellosis cases was on the rise in China. Hospital and community health service centers had highest case number and rate of duplicate reporting respectively, the duplicated reporting was mainly caused by re-reporting by other institutions or in other years. The duplicated reporting of brucellosis had greatly affected the accuracy of surveillance data of brucellosis in some provinces, such as Xinjiang and Ningxia. It is recommended to further strengthen brucellosis reporting management, improve data quality of NNDRS.