Epidemiological Characteristics Of Human Brucellosis Research Articles

Human brucellosis epidemiological characteristics in Qiqihar, Heilongjiang, 2004–2019

Objective To analyze the epidemiological characteristics of human brucellosis in Qiqihar of Heilongjiang province from 2004–2019, and provide scientific evidence for the development of brucellosis prevention and control strategy. Methods The time, geographical and population distributions of laboratory confirmed brucellosis case were analyzed with descriptive epidemiological method. Results A total of 25 999 laboratory-confirmed human brucellosis cases, without death, were reported online in Qiqihar from 2004 to 2019. The average annual incidence rate was 29.50/100 000, 11.17 times higher than national average (2.64/100 000) during the same period. The incidence of human brucellosis in Qiqihar was at a high level. There were two peaks in 2005 and 2012. The incidence increased significantly in 2019, with incidence rates of 23.56/100 000, the highest incidence was during March–July. The cases were aged from 9 months to 92 years. Most cases were middle-aged, men, farmers and herdsmen. The spread area of the disease was wide, the cases were reported in 94.60% of townships and 57.70% of all villages in 16 counties in 2012. In the non-occupational group, the proportions of the jobless or unemployed, students, workers, children outside child care settings were relatively high. The proportion of the jobless or employed was in increase. Conclusion The incidence of brucellosis in Qiqihar was much higher than the national level, Animal husbandry departments should strengthen the prevention and control of brucellosis. To reduce the incidence of human brucellosis, the quarantine, immunization and culling of livestock should be further strengthened, and health education and promotion should be implemented.

Changes in the epidemiological characteristics of human brucellosis in Shaanxi Province from 2008 to 2020

In the present study, surveys of case numbers, constituent ratios, conventional biotyping, and multilocus sequence typing (MLST) were applied to characterize the incidence rate and epidemiological characteristics of human brucellosis in Shaanxi Province, China. A total of 12,215 human brucellosis cases were reported during 2008–2020, for an annual average incidence rate of 2.48/100,000. The most significant change was that the county numbers of reported cases increased from 36 in 2008 to 84 in 2020, with a geographic expansion trend from northern Shaanxi to Guanzhong, and southern Shaanxi regions; the incidence rate declined in previous epidemic northern Shaanxi regions while increasing each year in Guanzhong and southern Shaanxi regions such as Hancheng and Xianyang. The increased incidence was closely related to the development of large-scale small ruminants (goats and sheep) farms in Guanzhong and some southern Shaanxi regions. Another significant feature was that student cases (n = 261) were ranked second among all occupations, accounting for 2.14% of the total number of cases, with the majority due to drinking unsterilized goat milk. Three Brucella species were detected (B. melitensis (bv. 1, 2, 3 and variant), B. abortus bv. 3/6, and B. suis bv. 1) and were mainly distributed in the northern Shaanxi and Guanzhong regions. Three known STs (ST8, ST2, and ST14) were identified based on MLST analysis. The characteristics that had not changed were that B. melitensis strains belonging to the ST8 population were the dominant species and were observed in all nine regions during the examined periods. Strengthened human and animal brucellosis surveillance and restriction of the transfer of infected sheep (goats) as well as students avoiding drinking raw milk are suggested as optimal control strategies.

Epidemiological Characteristics of Human Brucellosis - China, 2016-2019.

IntroductionBrucellosis is an important zoonotic infectious disease with its main mode of transmission from livestock to humans. The study analyzed epidemiological characteristics of human brucellosis from 2016 to 2019 in China, aiming to understand progress of the National Program of Brucellosis Prevention and Control. MethodsThe research obtained data on human brucellosis cases reported through China’s National Notifiable Disease Reporting System (NNDRS) from January 1, 2016 to December 31, 2019 and described brucellosis epidemiological patterns by region, seasonality, age, sex, and occupation. ResultsThe number of cases reported nationwide in China decreased from 47,139 (3.4/100,000) in 2016 to 37,947 (2.7/100,000) in 2018, and then increased to 44,036 (3.2/100,000) in 2019, with an average annual incidence of 3.0/100,000 during the four study years. Brucellosis in Xinjiang declined from 35.6/100,000 in 2016 to 16.3/100,000 in 2019 — an average annual decrease of 22.9%. Brucellosis in Inner Mongolia increased from 23.8/100,000 in 2016 to 54.4/100,000 in 2019 — an average increase of 31.8% per year and accounting for 22% of all reported cases. Northern China reported 95.2% of cases during this period and still had an incidence of 7.2/100,000 and 87.0% of counties being affected by brucellosis in 2019. In this region in 2019, males aged 45-64 years old had an incidence of over 15.9/100,000, compared with over 7.0/100,000 among females aged 45-64 years old. Conclusionslthough there was progress in prevention and control of human brucellosis in some provincial-level administrative divisions (PLADs) in 2016 through 2019, progress was limited nationwide and there was an overall resurgence of brucellosis in 2019. The resurgence was primarily in Inner Mongolia. An One Health approach should be strengthened to ensure successful and sustainable brucellosis prevention and control in China.

Human Brucellosis as an Epidemic Zoonosis in Zenica-Doboj Canton (Bosnia and Herzegovina) During 2008-2018

Background:Brucellosis is associated with people living in close proximity to their animals, where conditions for disease onset and spread exist. An epidemic of brucellosis in Bosnia and Herzegovina (B&H) has persisted since 2004. Zenica-Doboj Canton is one of the most affected areas.Objective:To investigate the epidemiological characteristics of human brucellosis from the year 2008 to2018.Methods:Data collected from paper-based patients/cases reported to the Epidemiology Department were analyzed.Results:After 2008, the annual number of patients diagnosed with brucellosis was decreasing, except in 2017 and 2018 with 20 and 35 cases, respectively. Within the 2008-2018 period, a total of 263 human brucellosis cases were recorded, decreasing from 102 (incidence of 44.7/100,000) cases in 2008 to three cases in 2012, but increased to 35 cases in 2018. Males were predominant, with a total of 205 (77.9%) cases. The mean age of the affected patients was 39.2 years; but the most affected age group was the 25-49 years age group with 117 (44.5%) cases. Most cases (151 cases, 66%) were reported during the period of March-July, and 242 (92%) cases were from the rural areas.Conclusion:With the implementation of the small ruminant vaccination program in 2009, the number of infected humans had declined, while brucellosis still remains.

Epidemiology of human brucellosis in Nahavand county, Hamadan Province, western Iran: an 8-year (2010-2017) registry-based analysis.

Brucellosis is an infectious zoonosis, which greatly afflicts human health and animal productivity. To describe the trends and epidemiological characteristics of human brucellosis in Nahavand county, Hamadan Province, western Iran over 8 years (2010-2017). In this registry-based longitudinal study, we analyzed all reported cases of human brucellosis, including 1,130 patients from 2010 to 2017. A checklist including demographic and clinical characteristics of patients with reported cases of brucellosis had been used to gather data. We calculated annual percent changes (APCs) and average annual percent changes (AAPCs) using Joinpoint software to determine the trend of brucellosis using a segmented regression model. Among the patients, 60.9% were male and 87.3% lived in rural areas. The mean age of the patients was 35.9 ± 18.34 years. Compared with male patients, female patients were more affected when they were elderly (15.6% men vs. 24.2% women for those aged ≥55 years) (P = 0.001). Of patients with brucellosis, 65.2% had consumed unpasteurized dairy products and 82.3% had a history of contact with animals. The incidence of human brucellosis in Nahavand county increased between 2010 and 2014, then decreased in 2015, and thereafter remained steady. Per 100,000 population, the AAPC pertaining to the incidence was 17.4 in the male population (95% CI: 4.4, 31.9), 13.8 in the female population (95% CI: 0.2, 29.3), and 16.1 in rural dwellers (95% CI: 2.2, 31.8) indicating an increasing trend from 2010 to 2017 (P < 0.05). The incidence of brucellosis in the western part of Iran is high and remains a challenging health problem. In the present study, age, job, sex, and seasonal changes are important risk factors for human brucellosis.

Epidemiological characteristics of human brucellosis in Tongliao city of Inner Mongolia Autonomous Region, 2004-2018

Objective: To analyze the epidemiological characteristics of human brucellosis (HB), evolution and origin feature of Brucella strains in Tongliao city, Inner Mongolia Autonomous Region during 2004-2018, and to provide evidence for strategy development against the disease. Methods: Data from the reports on HB in Tongliao during 2004-2018 were extracted from the China Information System for Disease Control and Prevention before being analyzed with software Excel 2016. Epidemiologic feature was described, using the number of cases, constituent ratio and related rates. Conventional biotypes methods were used for identification of species/biovars strains while species of six Brucella strains were further verified by AMOS-PCR. Cluster analyze on six Brucella strains were performed with Bio-Numerics 5.0 software and for examining and revealing the genetic characteristics of the related strains. Results: During 2004-2018, a total of 16 704 HB cases were reported, with the incidence rate as 35.41/100 000. The incidence rates appeared as 110.51/100 000 in Jarud Banner and 67.84/100 000 in Kulun flag, which were both higher than the other areas. Most of the cases were reported in the 40-54 year olds, which accounted for 48.75% (8 143/16 704). The number of HB in farmers appeared as 14 873, which counted for 89.04% (14 873/16 704) of all the cases. Male to female ratio of incidence was 2.40∶1. Most of the reported cases appeared between March to May, which accounted for 56.30% (9 405/16 704). Peak of the disease was seen in April. Using the conventional identification method, results showed that the available six strains all belonged to B. melitensis, including three of them as B. melitensis bv.1 and others three strains as B. melitensis bv. 3. Results from the amplified AMOS-PCR showed that all the strains were B. melitensis. The six strains clustered in two MLVA-11 genotypes (111 and 116) and all belonged to the Eastern Mediterranean lineage. Based on the MLVA-16 cluster analysis, results suggested that strains from this study were having close genetic relationship with B. melitensis strains that were from Jilin and Heilongjiang provinces. Conclusions: Human brucellosis identified in Tongliao area was with greater risk in spreading the disease to the vicinity. Our findings indicated that the programs on detection and control of the disease should be strengthened.

Epidemiologically characteristics of human brucellosis and antimicrobial susceptibility pattern of Brucella melitensis in Hinggan League of the Inner Mongolia Autonomous Region, China

BackgroundHinggan League is located in the Northeast of the Inner Mongolia Autonomous Region, the historically endemic area of animal and human brucellosis. In this study, the epidemiological characteristics of human brucellosis were analyzed, and the genotypic profile and antimicrobial susceptibilities of Brucella melitensis strains isolated from humans in Hinggan League were investigated.MethodsThe epidemic characteristics were described using case number, constituent ratio, and rate. The 418 human blood samples were collected and tested by bacteriology, and suspect colonies were isolated and identified by conventional biotyping assays, the VITEK 2.0 microbial identification system, and AMOS (Brucella abortus, B. melitensis, B. ovis, and B. suis)-PCR. Subsequently, all strains were genotyped using multiple-locus variable-number tandem repeat analysis (MLVA) assays, and the antimicrobial susceptibility pattern of Brucella strains against the 10 most commonly used antibiotics was determined by microdilution method.ResultsA total of 22 848 cases of human brucellosis were reported from 2004 to 2019, with an annual average incidence of 87.2/100 000. The incidence rates in developed areas of animal husbandry (Horqin Youyi Qianqi [161.2/100 000] and Horqin Youyi Zhongqi [112.1/100 000]) were significantly higher than those in forest areas (Arxan [19.2/100 000]) (χ2 = 32.561, P < 0.001). In addition, peak morbidity occurred during May–August, accounting for 72.6% (16582/22 848) of cases. The highest number of cases occurred in the 40+ age group, accounting for 44.4% (10 137/22484) of cases, and morbidity in males was significantly higher than that in females in all age groups (χ2 = 299.97, P < 0.001), the most common occupation was farmers. A total of 54 B. melitensis strains were divided into 37 genotypes (GT1–37) with 80–100% genetic similarity. All 25 strains were sensitive to seven tested antibiotics, phenotypic resistance to cotrimoxazole and azithromycin was observed in 5 (20%) and 25 (100%) of the isolates, respectively.ConclusionsHuman brucellosis exhibited a significant increasing trend and B. melitensis is the main pathogen responsible for human brucellosis in this region. Improved surveillance of infected animals (sheep) and limiting their transfer and trade are optional strategies for decreasing the incidence of this disease.

Epidemiology of human brucellosis and source of Brucella isolates in Hunan province

Objective: To analyze the epidemiological characteristics of human brucellosis and trace back source of infection of human brucellosis in Hunan province during 2010-2018, and provide evidence for the prevention and control of human brucellosis. Methods: The surveillance data of human brucellosis in Hunan during 2010-2018 were analyzed with software Excel 2016 and ArcGIS 10.5, the epidemic characteristics were described using cases number, constituent ratio and rate. The conventional biotype methods were used for the identification of Brucella species, UTS-PCR was applied to further confirm the results from conventional biotype detections, then six virulence genes of two clinical Brucella strains were detected by PCR assay. Cluster analysis of two Brucella strains were performed with Multiple locus variable-number tandem repeat analysis (MLVA) for the investigation of the infection source of human brucellosis. Results: From 2010 to 2018, a total of 728 human brucellosis cases were reported in Hunan with the annual incidence rate of 0.12/100 000. The incidence rate was 2.50/100 000 in Chenzhou and 1.90/100 000 in Yongzhou, higher than those in other areas. The number of counties reporting cases increased from 5 in 2010 to 69 in 2018. Most cases were reported in age group 45-54 years, accounting for 38.32% (279/728). The cases in farmers accounted for 59.07% (430/728) of the total. The male to female ratio of the cases was 2.75 ∶ 1. The reported case number was highest during May-July, accounting for 45.33% (330/728). The incidence was high in summer and autumn, and the peak was in May. The conventional identification showed that two strains were all Brucella melitensis biovar 1, consistent with UTS-PCR amplification results. Six virulence genes were found in two isolated strains, suggesting that the Brucella melitensis strains in this study had strong virulence. MLVA results confirmed that two strains detected in Hunan had complete identical MLVA-16 genotype with strains isolated from goat and camel in Inner Mongolia Autonomous Region, indicating that there was molecular epidemiology relationship between these strains and the source of infection were originated from Inner Mongolia. Conclusions: The epidemic of human brucellosis in Hunan is becoming serious, and disease has spread to general population and non-epidemic areas. Two Brucella melitensis strains detected in Hunan were originated from Inner Mongolia. The quarantine and inspection in animal transportation should be strengthened to prevent human outbreaks of brucellosis.

Epidemiological characteristics of human brucellosis in Hamadan Province during 2009–2015: results from the National Notifiable Diseases Surveillance System

BackgroundHuman brucellosis and recurrent brucellosis is an ever-increasing public health concern, especially in endemic areas like Iran. Nevertheless, little is known regarding the epidemiology and determinants of recurrent brucellosis. Therefore, the objective of this study was to investigate epidemiological patterns and potential determinants of recurrent brucellosis in Hamadan Province during the years 2009–2015. MethodsData on reported cases of new and recurrent brucellosis from 2009 to 2015 were obtained from the provincial Notifiable Diseases Surveillance System at Hamadan University of Medical Sciences. Incidence rates per 100000 were estimated at the county level. Binary logistic regression was used to estimate the effects of background characteristics and recurrent brucellosis. The power of discrimination of the model for recurrent brucellosis was assessed using the area under the curve (AUC). ResultsAmong 7318 brucellosis cases, the total frequency (%) of recurrent cases was 472 (6.45%). The rate of recurrent brucellosis was higher in females, people aged 50 years and over, people with a history of consuming unpasteurized dairy products with no history of contact with animals, and in the winter season. Multivariable logistic regression analysis showed that female sex (adjusted odds ratio (AOR) 1.36, 95% confidence interval (CI) 1.13–1.65), age ≥55 years (AOR 4.15, 95% CI 2.32–7.42), consumption of unpasteurized dairy products (AOR 1.16, 95% CI 0.96–1.40), and winter season (AOR 1.32, 95% CI 1.03–1.71) are potential risk factors for recurrent brucellosis. The final model that involved all the determinants showed moderate discrimination (AUC 0.61). ConclusionsFemale sex, older age, and winter months were found to be significant determinants of recurrent human brucellosis. Enhanced surveillance systems with an emphasis on these population characteristics will allow effective preventive and protective measures to be implemented and might alleviate the recurrence of brucellosis in the country.

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

Objective: To analyze the epidemiological characteristics of human brucellosis in northern and southern areas of China, and to develop national strategies for brucellosis prevention and control. Methods: Individual data on human brucellosis was collected from the National Notifiable Infectious Disease Reporting Information System to describe the situation of brucellosis in China during 2015-2016. Epidemiological features of the disease in northern and southern areas of China were analyzed. Results: A total of 104 125 cases were reported in mainland China during 2015-2016, with an average incidence rate as 3.81/100 000. The overall incidence rate from the northern provinces was 7.77/100 000 in 2016, a 18.6% decrease from 2015 (9.55/100 000), whereas the incidence rate in the southern provinces was 0.27/100 000 in 2016, with an increase of 28.6% than 0.21/100 000 in 2015. 90.0% of the newly infected counties mainly distributed in southern China. As for the locations of reporting cases, most of them were in the same counties in the northern areas (52.3%) while most cases in the southern areas (59.6%) were imported from other counties. The median age of the cases was 48 (IQR: 38-58) years, with male-to-female ratios as 2.7∶1 in the north and 2.2∶1 in the south. Majority of the cases were occupation-related, from both the northern (86.8%) and southern (62.7%) areas. Human brucellosis occurred every month throughout the year but with an obvious seasonal increase between March and July. Conclusions: 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.

Epidemiological characteristics of human brucellosis in Al-Qassim region, Saudi Arabia, between 2010 and 2014

Background: Brucellosis, a zoonotic infection having an important public health issue in endemic countries; Saudi Arabia is one of these countries. The incidence of brucellosis in AlQassim region is much higher than the national one. Evaluation of the epidemiological situation of brucellosis is the first step in prevention and control. The objective was to describe the epidemiological characteristics of brucellosis in Al-Qassim region during the period between 2010 and 2014. Methods: All epidemiological surveillance forms from 2010 to 2014 were analyzed for epidemiological characteristics. Results: There were 4283 notified cases of human brucellosis in AL-Qassim region between 2010 and 2014, the annual incidence decreased from 84.5 to 48.7 per 100,000 populations. The highest number of cases was reported from Uyoon Al-Jawa followed by Buraidah. The number of cases was highest from March to June. and lowest was in November; the male to female ratio was 3:1. Saudis represents 51.1% of cases. The mean age of the cases was 34±15 years; the most common age group was middle age. Shepherds and farmers represent 46.5% of cases. The most common presenting symptoms were fever (79.7%), joint pain (72.7%), and muscle pain (70.9%). The most common antibiotics used as treatment were doxycycline (80.9%) and streptomycin (63.2%). A history of animal contact was the most common risk factor (80.7%), followed by consumption of raw milk (55.6%). Conclusions: There was a marked decrease in the incidence of brucellosis from 2010 to 2014 in the Al-Qassim region. However, continued efforts are needed to eliminate the disease.

Epidemiological characteristics of brucellosis in Serbia, 1980-2008.

To analyze the epidemiological characteristics of human brucellosis in Serbia from 1980 to 2008 and the most important factors affecting its emergence and spread. Public sources of data on brucellosis were used, including official reports of infectious diseases and epidemics, as well as monthly and annual reports of the Serbia and Vojvodina Institutes of Public Health. From 1980 through 2008, there were 1521 human brucellosis cases in Serbia. The annual number ranged from 2 in 2000 to 324 in 1991. Infections occurred more often in men (67% of cases) than in women (odds ratio, 2.17; 95% confidence interval, 1.57-3.00; chi2=24.52, P<0.001). The largest number of patients over the entire study period (1184) was recorded in Kosovo and Metohija, which accounted for 78% of the total number of patients. The maximum incidence rate in Kosovo and Metohija was 12 per 100,000 in 1991. In Vojvodina, the first autochthonous human cases of brucellosis were recorded in 1999, and 101 affected persons were registered by the end of 2008. During the period 1994-2008, the largest number of patients in Serbia was recorded from June to September (310 of 623 cases, 50%). The disease was most prevalent among people aged 30-49 years, accounting for 81 of 177 (46%) of the cases in Serbia from 1999 to 2008. Brucellosis has been a significant public health concern in Serbia. This problem may be solved by joint efforts of all relevant factors, first of all human and veterinary medical services.