Changing epidemiology of human brucellosis, Germany, 1962-2005

Effector Proteins of Type IV Secretion System: Weapons of Brucella Used to Fight Against Host Immunity

Brucella is an intracellular bacterial pathogen capable of long-term persistence in the host, resulting in chronic infections in livestock and wildlife. The type IV secretion system (T4SS) is an important virulence factor of Brucella and is composed of 12 protein complexes encoded by the VirB operon. T4SS exerts its function through its secreted 15 effector proteins. The effector proteins act on important signaling pathways in host cells, inducing host immune responses and promoting the survival and replication of Brucella in host cells to promote persistent infection. In this article, we describe the intracellular circulation of Brucella-infected cells and survey the role of Brucella VirB T4SS in regulating inflammatory responses and suppressing host immune responses during infection. In addition, the important mechanisms of these 15 effector proteins in resisting the host immune response during Brucella infection are elucidated. For example, VceC and VceA assist in achieving sustained survival of Brucella in host cells by affecting autophagy and apoptosis. BtpB, together with BtpA, controls the activation of dendritic cells during infection, induces inflammatory responses, and controls host immunity. This article reviews the effector proteins secreted by Brucella T4SS and their involvement in immune responses, which can provide a reliable theoretical basis for the subsequent mechanism of hijacking the host cell signaling pathway by bacteria and contribute to the development of better vaccines to effectively treat Brucella bacterial infection.

Seroprevalence of Brucella Infection in Wild Boars (Sus scrofa) of Bavaria, Germany, 2019 to 2021 and Associated Genome Analysis of Five B. suis Biovar 2 Isolates

Brucella species are highly pathogenic zoonotic agents and are found in vertebrates all over the world. To date, Germany is officially declared free from brucellosis and continuous surveillance is currently limited to farm ruminants. However, porcine brucellosis, mostly caused by B. suis biovar 2, is still found in wild boars and hares. In the present study, a three-year monitoring program was conducted focusing on the wild boar population in the state of Bavaria. Serologic screening of 11,956 animals and a direct pathogen detection approach, including a subset of 681 tissue samples, was carried out. The serologic incidence was 17.9%, which is in approximate accordance with previously published results from various European countries. Applying comparative whole genome analysis, five isolated B. suis biovar 2 strains from Bavaria could be assigned to three known European genetic lineages. One isolate was closely related to another strain recovered in Germany in 2006. Concluding, porcine brucellosis is endemic in Bavaria and the wild boar population represents a reservoir for genetically distinct B. suis biovar 2 strains. However, the transmission risk of swine brucellosis to humans and farm animals is still regarded as minor due to low zoonotic potential, awareness, and biosafety measures.

Prevalence, diagnosis, and manifestations of brucellosis: A systematic review and meta-analysis

Objectives

Brucellosis is one of the most prevalent zoonotic diseases common between humans and animals. Despite eradication efforts, the burden of the disease is well-known in endemic countries and in countries where brucellosis has not been an important health issue until recently. The aim of this study was to evaluate the prevalence, diagnosis, and manifestations of brucellosis.

Methods

In this study, PubMed, Web of Science, Scopus, Embase, and Google scholar databases were systematically searched to find studies published from 2011 to 2021. The search was conducted using text words and Medical Subject Headings (MeSH) Terms on the prevalence of brucellosis. Stata software 14.0 was used for all analyses.

Results

Based on the results, the pooled prevalence of brucellosis was 15.27% (95% CI: 9.68-21.86; heterogeneity I 2 index: 97.43; p < 0.001) for man and 15.33% (95% CI: 7.19-25.75; heterogeneity I 2 index: 98.19; p < 0.001) for woman. Age (coefficient: 0.240; p = 0.480), gender (coefficient: -0.017; p = 0.800), and publication year (coefficient: 0.114; p = 0.861) showed no significant effect on heterogeneity among studies. Egger's test indicated a significant publication bias for the prevalence of brucellosis (coefficient 3.894; p < 0.001). Moreover, the trim-and-fill method exhibited that the adjusted prevalence of brucellosis (18.30%, 95% CI: 14.10-22.52) was not significantly different from the original prevalence of brucellosis.

Conclusion

The pooled estimate for brucellosis prevalence was estimated as 15.53%. To better understand the epidemiology of brucellosis globally, more extensive studies are needed to be conducted throughout the world, especially in developing and low-income countries.

Methodological choices in brucellosis burden of disease assessments: A systematic review

BACKGROUND

Foodborne and zoonotic diseases such as brucellosis present many challenges to public health and economic welfare. Increasingly, researchers and public health institutes use disability-adjusted life years (DALYs) to generate a comprehensive comparison of the population health impact of these conditions. DALYs calculations, however, entail a number of methodological choices and assumptions, with data gaps and uncertainties to accommodate. Thisreview identifies existing brucellosis burden of disease studies and analyzes their methodological choices, assumptions, and uncertainties. It supports the Global Burden of Animal Diseases programme in the development of a systematic methodology to describe the impact of animal diseases on society, including human health.

METHODS/PRINCIPAL FINDINGS

A systematic search for brucellosis burden of disease calculations was conducted in pre-selected international and grey literature databases. Using a standardized reporting framework, we evaluated each estimate on a variety of key methodological assumptions necessary to compute a DALY. Fourteen studies satisfied the inclusion criteria (human brucellosis and quantification of DALYs). One study reported estimates at the global level, the rest were national or subnational assessments. Data regarding different methodological choices were extracted, including detailed assessments of the adopted disease models. Most studies retrieved brucellosis epidemiological data from administrative registries. Incidence data were often estimated on the basis of laboratory-confirmed tests. Not all studies included mortality estimates (Years of Life Lost) in their assessments due to lack of data or the assumption that brucellosis is not a fatal disease. Only two studies used a model with variable health states and corresponding disability weights. The rest used a simplified singular health state approach. Wide variation was seen in the duration chosen for brucellosis, ranging from 2 weeks to 4.5 years, irrespective of the whether a chronic state was included.

CONCLUSION

Available brucellosis burden of disease assessments vary widely in their methodology and assumptions. Further research is needed to better characterize the clinical course of brucellosis and to estimate case-fatality rates. Additionally, reporting of methodological choices should be improved to enhance transparency and comparability of estimates. These steps will increase the value of these estimates for policy makers.

Trends in the Epidemiology of Brucellosis Cases in Iran during the Last Decade

Background

Brucellosis is one of the most important zoonotic diseases that impose a serious public health burden on some countries in the world. Annually, the WHO reports more than 500000 new cases of human brucellosis. The disease is endemic in most parts of Iran; especially, in areas where people live in close contact with infected animals. According to data from the Iranian Ministry of Health, the average incidence of brucellosis in Iran was 22 cases per 100000 population, with a decreasing trend of surveillance.

Methods

This cross-sectional survey was carried out within 2011-2020 in all provinces of Iran and from patients with clinical symptoms.

Results

During the last decade, a total of 173526 cases were reported from different provinces of Iran, with a higher frequency of occurrence in males (58.2%) living in rural areas (77%), as compared to those in urban areas (23%). Moreover, brucellosis was more common in the summer season (June) and most of the cases were via contact with infected livestock (91%) and consumption of unpasteurized dairy products (78% in rural areas and 76% in the urban areas).

Conclusion

The failure to effectively control brucellosis may be attributed to lack of knowledge about the disease, consumption of unpasteurized dairy and raw meat, lack of proper and safe vaccines for prevention and eradication programs, lack of rapid detection systems, and ineffective methods of isolating infected animals. Therefore, education and advancement of people's knowledge are key to the prevention and control of the disease.

The Retrospective on Atypical Brucella Species Leads to Novel Definitions

The genus Brucella currently comprises twelve species of facultative intracellular bacteria with variable zoonotic potential. Six of them have been considered as classical, causing brucellosis in terrestrial mammalian hosts, with two species originated from marine mammals. In the past fifteen years, field research as well as improved pathogen detection and typing have allowed the identification of four new species, namely Brucella microti, Brucella inopinata, Brucella papionis, Brucella vulpis, and of numerous strains, isolated from a wide range of hosts, including for the first time cold-blooded animals. While their genome sequences are still highly similar to those of classical strains, some of them are characterized by atypical phenotypes such as higher growth rate, increased resistance to acid stress, motility, and lethality in the murine infection model. In our review, we provide an overview of state-of-the-art knowledge about these novel Brucella sp., with emphasis on their phylogenetic positions in the genus, their metabolic characteristics, acid stress resistance mechanisms, and their behavior in well-established in cellulo and in vivo infection models. Comparison of phylogenetic classification and phenotypical properties between classical and novel Brucella species and strains finally lead us to propose a more adapted terminology, distinguishing between core and non-core, and typical versus atypical brucellae, respectively.

Microbiological Laboratory Diagnosis of Human Brucellosis: An Overview

Brucella spp. are Gram-negative, non-motile, non-spore-forming, slow-growing, facultative intracellular bacteria causing brucellosis. Brucellosis is an endemic of specific geographic areas and, although underreported, represents the most common zoonotic infection, with an annual global incidence of 500,000 cases among humans. Humans represent an occasional host where the infection is mainly caused by B. melitensis, which is the most virulent; B. abortus; B. suis; and B. canis. A microbiological analysis is crucial to identifying human cases because clinical symptoms of human brucellosis are variable and aspecific. The laboratory diagnosis is based on three different microbiological approaches: (i) direct diagnosis by culture, (ii) indirect diagnosis by serological tests, and (iii) direct rapid diagnosis by molecular PCR-based methods. Despite the established experience with serological tests and highly sensitive nucleic acid amplification tests (NAATs), a culture is still considered the “gold standard” in the laboratory diagnosis of brucellosis due to its clinical and epidemiological relevance. Moreover, the automated BC systems now available have increased the sensitivity of BCs and shortened the time to detection of Brucella species. The main limitations of serological tests are the lack of common interpretative criteria, the suboptimal specificity due to interspecies cross-reactivity, and the low sensitivity during the early stage of disease. Despite that, serological tests remain the main diagnostic tool, especially in endemic areas because they are inexpensive, user friendly, and have high negative predictive value. Promising serological tests based on new synthetic antigens have been recently developed together with novel point-of-care tests without the need for dedicated equipment and expertise. NAATs are rapid tests that can help diagnose brucellosis in a few hours with high sensitivity and specificity. Nevertheless, the interpretation of NAAT-positive results requires attention because it may not necessarily indicate an active infection but rather a low bacterial inoculum, DNA from dead bacteria, or a patient that has recovered. Refined NAATs should be developed, and their performances should be compared with those of commercial and home-made molecular tests before being commercialized for the diagnosis of brucellosis. Here, we review and report the most common and updated microbiological diagnostic methods currently available for the laboratory diagnosis of brucellosis.

Analysis of Electrocardiogram Among 108 Patients with Brucella

Objective

To improve our knowledge of cardiac manifestations caused by brucellosis through analyzing abnormal electrocardiograms of patients infected with brucella.

Methods

A total of 108 cases were enrolled, and their electrocardiograms were analyzed and summarized retrospectively.

Results

Among 108 cases, 77 (71.3%) had a normal electrocardiogram, and 31 (28.7%) had an abnormal electrocardiogram. There were 13 cases with nodal tachycardia (12%), 9 cases with sinus bradycardia (8%), 7 cases with sinus arrhythmia (6%), 8 cases with left ventricular high voltage (7%), 13 cases with abnormal ST segment and T wave (12%), 2 cases with abnormal Q wave (1.85%), 3 cases with complete right bundle branch block (2.78%), 3 cases with ventricular premature beat (2.78%), 1 case with left anterior fascicular block (0.9%), 1 case with first degree a-v block (0.9%), 1 case with QT internal prolongation (0.9%), 1 case with poor R wave progression (0.9%), and 1 case with short PR interval (0.9%).

Conclusion

The cardiac manifestations of brucellosis were rare, but the mortality was high. Patients with abnormal electrocardiogram should have improved echocardiography in time. Early detection of the abnormal electrocardiogram could give a hint of cardiac damage to avoid the serious consequences.

The Incidence and Geographical Distribution of Brucellosis in Iran Using Geographic Information System and Prediction of its Incidence in 2021

BACKGROUND

Brucellosis is one of the most challenging health issues in many developing countries including Iran. The purpose of this study is to investigate the incidence and geographical distribution of brucellosis using Geographic Information System (GIS) and to predict its incidence in Iran in 2021.

METHOD

This is a descriptive-analytical cross-sectional study, which contains spatial and climatic information along with the prevalence rate of brucellosis in Iran. Disease information was obtained from the National Center for Infectious Diseases Management during 2011-2015. Then, Arc GIS version 9.3 was used to plot the geographical maps for the incidence and frequency of the disease. Using the Raster calculator tool, the disease prediction map for the future was plotted. For proper spatial distribution of hot and cold spots, Getis-Ord-Gi statistic was employed.

FINDINGS

The highest incidence of brucellosis during 2009-2015 was observed in the western provinces of Iran (North Khorasan, South Khorasan and Razavi Khorasan provinces). The incidence of brucellosis in Iran decreased from 2009 to 2011 but it exhibited an increasing trend from 2011 to 2014. The provinces of Kurdistan, Lorestan, Ilam, Zanjan and Kermanshah may be among the hot spots in terms of brucellosis incidence in 2021.

CONCLUSION

We predicted significant variations in brucellosis risk distribution in Iran in the coming years. In the western and northwestern provinces, which are among the high risk areas for the incidence of this disease in the future, this disease can pose a serious health threat to the residents of these areas.

An epidemiological study of brucellosis on mainland China during 2004-2018

Brucellosis has re-emerged in China in recent years, resulting in an increasing health burden and economic losses for humans and the livestock industries. This study integrated data from human and livestock brucellosis surveillance systems to explore the changing epidemiology of brucellosis from 2004 to 2018 in China. A total of 524,980 human cases of brucellosis were reported, with the average annual incidence in humans being significantly higher for the period 2012-2018 than for 2004-2011 (3.3 vs. 1.9 per 100,000 residents). An autoregressive integrated moving average (ARIMA) model predicted an upward trend in the monthly incidence of brucellosis in humans in 2019 and 2020. Characteristics including being male, aged 45-54 years, working in the livestock industries, and residing in the northern provinces of China increased the risk of people contracting brucellosis. The percentage of provinces with infected people increased from 67.7% (21/31) in 2004 to all provinces in 2018. A total of 29,115 outbreaks were reported in livestock from 2004 to 2018, with 443,883 seropositive animals although only 381,224 (85.9%) of these were culled. The monthly incidence of brucellosis in humans was strongly positively correlated (r = .539, p < .001) with the number of outbreaks of brucellosis in livestock reported 3 months prior to the human cases. At the provincial level, the annual incidence of brucellosis in humans was significantly positively correlated with the sheep population (r = .786, p < .01). In conclusion, brucellosis in humans and livestock has been spreading in mainland China in the past decade. A more active surveillance of brucellosis in both livestock and humans in China should be coordinated and adjusted by adopting an evidence-based 'One Health' approach, particularly in high-risk regions and livestock industries.

Serosurvey and Risk Factors Associated with Brucella Infection in High Risk Occupations from District Lahore and Kasur of Punjab, Pakistan

Brucellosis is a neglected zoonotic disease, and occupations with a high risk of infection exist. Limited information is available on brucellosis for these employees at high risk in Pakistan. A total of 459 persons with high-risk occupations, i.e., 211 abattoir workers, 63 milkers, 52 dung cake makers, 44 veterinarians, 44 shepherds, and 45 veterinary students of the districts Kasur and Lahore, Pakistan, were tested in this study. Blood samples and information on place of residence, gender, age, urbanicity, type of occupation, socioeconomic status, contact with animals, consumption of raw milk, contact to women who had a miscarriage, contact to aborted animal fetus or abortion material, pregnancy, miscarriage history, or intrauterine fetal death were collected. Serum samples were examined using Rose Bengal tests for anti-Brucella antibodies and seropositive samples were subjected to genus-specific qPCR for the detection of DNA. Data were analyzed using chi-squared and binary regression. Twenty (4.35%) persons were seropositive for anti-Brucella antibodies. Out of these, 18 (90%) were tested positive by Brucella genus-specific qPCR. Positive sera were more often found in Lahore district (8.3%) than in Kasur district (3.1%). Persons older than 36 years were more often seropositive. Persons involved in the handing of milk and in contact with animals were more often seropositive. Contact with women who had had a miscarriage was also a significant factor for seropositivity for brucellosis. Place of residence, gender, age, urbanicity, and contact with animals were identified as potential risk factors in the present study. The present study confirmed that brucellosis is an occupation hazard for abattoir workers, milkers, dung cake makers, and veterinarians in the districts of Lahore and Kasur of Punjab, Pakistan. The study shows the need for strategies for safety at work to minimize the risk of infection. Raising awareness for the prevention and use of proper personal protection equipment during the slaughtering and treatment of animal is highly needed.

Investigation of Genetic Relatedness of Brucella Strains in Countries Along the Silk Road

In this study, MLVA (multiple-locus variable-number tandem repeat analysis) genotype data of Brucella strains from 11 countries along the Silk Road were downloaded from the MLVAbank. MLVA data of strains were applied to the constructed Minimum Spanning Tree to explore the species/biovars distribution, geographic origins, and genetic relationships of the strains analyzed. Moreover, whole-genome sequencing–single-nucleotide polymorphism (WGS-SNP) phylogenetic analysis of the genome of Brucella melitensis strains from GenBank was performed to discriminate the relatedness of strains further and investigate the transmission pattern of B. melitensis brucellosis. A total of 1,503 Brucella strains were analyzed in this study: 431 Brucella abortus strains (29.8%), 1,009 B. melitensis strains (65.7%), and 63 Brucella suis strains (4.5%). B. melitensis biovar 3 was the dominant species and was shown to be widespread in all of the examined regions, suggesting that the prevention and surveillance of the B. melitensis population are a main challenge in these countries. A wide host spectrum was observed for this Brucella population; many animal reservoirs are a potential reason for the continuous brucellosis circulation in these countries. Although the B. abortus strains from the examined regions had common geographic origins, only a few shared genotypes were observed in different countries. These data revealed that the majority of B. abortus strains were spreading within the national borders. However, the B. melitensis strains from Italy originated from a Western Mediterranean lineage; strains from the other 10 countries originated from Eastern Mediterranean lineage, and this lineage was shared by strains from three to nine different countries, suggesting that the introduction and reintroduction of the disease in the 10 countries might have occurred in the past. Furthermore, the most shared MLVA-16 genotypes were formed in the B. melitensis strains from China, Kazakhstan, and Turkey, suggesting that the introduction and trade in sheep and goats have occurred frequently in these countries. WGS-SNP analysis showed that the B. melitensis in this study originated from the Malta (Italy) region. According to their territorial affiliation between four clade strains from these countries in genotype B, the absence of a clear differentiation suggests that strains continuously expand and spread in countries along with Silk Road. Active exchange and trade of animals (sheep and goats) among these countries are reasonable explanations. B. suis strains from different nations showed unique geographic origins and epidemiological characteristics. Therefore, there is an urgent need for the control of transfer and trade of infected sheep (goats) in countries along the Silk Road, namely, the strengthening of the entry–exit quarantine of sheep and goats and improvements in the diagnosis of animal brucellosis.

Acute Brucellosis and Cirrhosis: The Triggering Event of Fatal Liver Decompensation

Cirrhotic patients are known to be particularly susceptible to infectious complications that may vary according to regional endemic patterns. Brucellosis, a common zoonosis with worldwide distribution, exhibits a predilection for the reticuloendothelial system and thus resulting in hepatic involvement. We describe three cirrhotic patients in whom acute brucellosis and/or its treatment served as the triggering factor of hepatic decompensation, with deleterious effects. The patients suffered from alcoholic cirrhosis and culture-proven brucellosis. All patients came from an area endemic to brucellosis. The first patient exhibited a relapsing brucellosis course with progressive deterioration of his fragile liver function. The second patient progressed rapidly to jaundice, possibly partly attributed to antibiotic pharmacotoxicity, and died during liver transplantation. The third patient eventually succumbed to diffuse intravascular coagulation. Brucellosis can be a triggering event of fatal liver decompensation in cirrhotic patients. Enhancing health literacy of the patients, particularly in endemic areas, is of paramount importance for prevention of exposure to similar pathogens.

Evolutionary history and current distribution of the West Mediterranean lineage of Brucella melitensis in Italy

Ovine and caprine brucellosis, caused by Brucella melitensis, is one of the world’s most widespread zoonoses and is a major cause of economic losses in domestic ruminant production. In Italy, the disease remains endemic in several southern provinces, despite an ongoing brucellosis eradication programme. In this study, we used whole-genome sequencing to detail the genetic diversity of circulating strains, and to examine the origins of the predominant sub-lineages of B. melitensis in Italy. We reconstructed a global phylogeny of B. melitensis, strengthened by 339 new whole-genome sequences, from Italian isolates collected from 2011 to 2018 as part of a national livestock surveillance programme. All Italian strains belonged to the West Mediterranean lineage, which further divided into two major clades that diverged roughly between the 5th and 7th centuries. We observed that Sicily serves as a brucellosis burden hotspot, giving rise to several distinct sub-lineages. More than 20 putative outbreak clusters of ovine and caprine brucellosis were identified, several of which persisted over the 8 year survey period despite an aggressive brucellosis eradication campaign. While the outbreaks in Central and Northern Italy were generally associated with introductions of single clones of B. melitensis and their subsequent dissemination within neighbouring territories, we observed weak geographical segregation of genotypes in the southern regions. Biovar determination, recommended in routine analysis of all Brucella strains by the World Organisation for Animal Health (OIE), could not discriminate among the four main global clades. This demonstrates a need for updating the guidelines used for monitoring B. melitensis transmission and spread, both at the national and international level, and to include whole-genome-based typing as the principal method for identification and tracing of brucellosis outbreaks.

Occupational exposure to Brucella spp.: A systematic review and meta-analysis

Brucellosis is a neglected zoonotic disease of remarkable importance worldwide. The focus of this systematic review was to investigate occupational brucellosis and to identify the main infection risks for each group exposed to the pathogen. Seven databases were used to identify papers related to occupational brucellosis: CABI, Cochrane, Pubmed, Scielo, Science Direct, Scopus and Web of Science. The search resulted in 6123 studies, of which 63 were selected using the quality assessment tools guided from National Institutes of Health (NIH) and Case Report Guidelines (CARE). Five different job-related groups were considered greatly exposed to the disease: rural workers, abattoir workers, veterinarians and veterinary assistants, laboratory workers and hunters. The main risk factors and exposure sources involved in the occupational infection observed from the analysis of the articles were direct contact with animal fluids, failure to comply with the use of personal protective equipment, accidental exposure to live attenuated anti-brucellosis vaccines and non-compliance with biosafety standards. Brucella species frequently isolated from job-related infection were Brucella melitensis, Brucella abortus, Brucella suis and Brucella canis. In addition, a meta-analysis was performed using the case-control studies and demonstrated that animal breeders, laboratory workers and abattoir workers have 3.47 [95% confidence interval (CI); 1.47-8.19] times more chance to become infected with Brucella spp. than others individuals that have no contact with the possible sources of infection. This systematic review improved the understanding of the epidemiology of brucellosis as an occupational disease. Rural workers, abattoir workers, veterinarians, laboratory workers and hunters were the groups more exposed to occupational Brucella spp. infection. Moreover, it was observed that the lack of knowledge about brucellosis among frequently exposed professionals, in addition to some behaviors, such as negligence in the use of individual and collective protective measures, increases the probability of infection.

Seroprevalence of some viral and bacterial zoonoses in domestic ruminants in Medina

OBJECTIVE

The study aimed to explore the seroprevalence of some bacterial (Brucella spp., Chlamydia abortus) and viral [Rift Valley fever virus (RVFV), foot and mouth disease virus (FMDV)] zoonoses in domestic ruminants in Medina.

MATERIALS AND METHODS

A total of 1,000 blood samples from 665 sheep, 228 goats, and 107 camels were collected from the central slaughterhouse, private farms, and veterinary clinics affiliated to the Ministry of Agriculture. The samples were screened using the Enzyme-Linked Immunosorbent Assay (ELISA). The results were statistically analyzed using Statistical Package for the Social Sciences version 20.

RESULTS

Brucella was found in 7.7%, 8.8%, and 6.5% of sheep, goats, and camel's sera, respectively. In humans, Brucella abortus and Brucella melitensis had higher frequencies in males (61.3%, 59.8%) than in females (38.7%, 40.2%). Chlamydia abortus was reported only in sheep at a rate of 0.75%. RVFV was prevalent in sheep (10.7%) and goats (17.9%). FMDV was reported in 27.8% of sheep and 7.9% of goats. There was a highly statistical significance between Brucella, RVFV, and FMDV seropositivity and locally bred animals (p < 0.01). Multiple seropositivities have been reported among sheep and goats. Brucella was commonly observed in mixed infection with other bacterial and viral agents under study.

CONCLUSION

The surveyed viral and bacterial agents were prevalent in ruminants in the Medina region. Since Medina is an important destination for pilgrims from all over the world, therefore, an integrated approach involving strict control measures and routine vaccination programs should be adopted to reduce the possibility of global epidemics.

Epidemiological trends of notified human brucellosis in Germany, 2006-2018

OBJECTIVE

We describe epidemiological trends of human brucellosis in Germany over a 13 year period based on national surveillance data.

METHODS

We analyzed demographic, clinical, laboratory and exposure information of symptomatic laboratory-confirmed brucellosis cases notified 2006-18. Using official population data, we calculated incidences and risk ratios (RR).

RESULTS

From 2006 to 2018, 408 brucellosis cases were notified in Germany (mean annual incidence: 0.38/1,000,000 population), of which 75% were travel-associated. Yearly notifications peaked in 2014 (n = 47) and remained elevated compared to 2006-2013 (mean: n = 25). Asylum seekers (AS) arriving in Germany accounted for 9/44 (2015) and 15/36 (2016) cases, respectively. RR AS/non-AS 2015-2016: 28, 95% CI: 17-45. Unpasteurized milk products were most frequently notified as source of infection. Imported food and occupational exposure played a role in autochthonous cases.

CONCLUSIONS

The incidence of human brucellosis has markedly increased in recent years. Most of the observed rise in notifications can be explained by infections in AS. Exposure still predominantly occurs abroad. Risk factors for autochthonous infections need to be investigated further, though imported dairy products seem to play a role. Physicians should consider brucellosis as differential diagnosis in AS and people with travel to endemic regions with compatible symptoms.

Laboratory Diagnosis of Human Brucellosis

The clinical presentation of brucellosis in humans is variable and unspecific, and thus, laboratory corroboration of the diagnosis is essential for the patient's proper treatment. The diagnosis of brucellar infections can be made by culture, serological tests, and nucleic acid amplification assays. Modern automated blood culture systems enable detection of acute cases of brucellosis within the routine 5- to 7-day incubation protocol employed in clinical microbiology laboratories, although a longer incubation and performance of blind subcultures may be needed for protracted cases. Serological tests, though they lack specificity and provide results that may be difficult to interpret in individuals repeatedly exposed to Brucella organisms, nevertheless remain a diagnostic cornerstone in resource-poor countries. Nucleic acid amplification assays combine exquisite sensitivity, specificity, and safety and enable rapid diagnosis of the disease. However, long-term persistence of positive molecular test results in patients that have apparently fully recovered is common and has unclear clinical significance and therapeutic implications. Therefore, as long as there are no sufficiently validated commercial tests or studies that demonstrate an adequate interlaboratory reproducibility of the different homemade PCR assays, cultures and serological methods will remain the primary tools for the diagnosis and posttherapeutic follow-up of human brucellosis.

Research Progress on Brucellosis

Brucellosis is a debilitating febrile illness caused by an intracellular Brucella. The disease is distributed in humans and animals widely, especially in developing countries. Ten species are included in the genus Brucella nowadays; four species of them are pathogenic to humans, which make brucellosis a zoonosis with more than 500,000 new cases reported annually. For human brucellosis, the most pathogenic species is B. melitensis followed by B. suis, while B. abortus is the mildest type of brucellosis. The infection mechanism of Brucella is complicated and mostly relies on its virulence factors. The therapy of the disease contains vaccination and antibiotic. However, there are some defects in currently available vaccines such as the lower protective level and safety. Thus, safe and efficient vaccines for brucellosis are still awaited. The dual therapy of antibacterial is effective in the treatment of brucellosis if a rapid and exact detection method is found.

A primary investigation of the relation between the incidence of brucellosis and climatic factors in Iran

Brucella spp. are Gram-negative coccobacilli that may grow in different media and environmental conditions for extended periods of time. The survivals of these bacteria in the environment have an important impact on the epidemiology of brucellosis worldwide. The effect of climate on the incidence of certain zoonotic infectious diseases, (recently referred to as climate-sensitive zoonosis) is now well established. The aim of this study was to evaluate the relation between the incidence of brucellosis and climatic parameters in Iran, an important endemic region for brucellosis with diverse climate. The information on the incidence of human brucellosis in different Iranian provinces for 2016 has been provided by the Ministry of Health and Medical Education, Iran. Annual meteorological data collected between 2015 and 2016 were obtained from the Iranian Meteorological organization (IMO). A regression analysis of the incidence of brucellosis was performed via STATA 14.0 and the heterogeneity among observations was determined via Cochrane's Q-test and I² statistic. If I² index was higher than 50%, heterogeneity was considered as considerable. The results of regression analyses revealed a negative significant association between mean ambient air temperature and brucellosis incidence (C = - 0.022, P value = 0.004). Likewise, a positive significant association was found between number of frosty days and brucellosis incidence (C = 0.002, p value = 0.003). Other metrological parameters showed no significant effect on the human brucellosis incidence. Although our results suggest a high degree of temperature sensitivity in regards to the brucellosis incidence in Iran, this study opens up prospects for further investigations regarding environmental conditions and climatic changes influencing the spatial distributions and seasonal/annual cycle of this zoonotic pathogen worldwide.

Whole Genome Sequencing for Tracing Geographical Origin of Imported Cases of Human Brucellosis in Sweden

Human infections with Brucella melitensis are occasionally reported in Sweden, despite the fact that the national flocks of sheep and goats are officially free from brucellosis. The aim of our study was to analyze 103 isolates of B. melitensis collected from patients in Sweden between 1994 and 2016 and determine their putative geographic origin using whole genome sequencing (WGS)-based tools. The majority of the strains were assigned to East Mediterranean and African lineages. Both in silico Multiple Loci VNTR (Variable Number of Tandem Repeats) Analysis (MLVA) and core genome Multilocus Sequence Typing (cgMLST) analyses identified countries of the Middle East as the most probable source of origin of the majority of the strains. Isolates collected from patients with travel history to Iraq or Syria were often associated with genotypes from Turkey, as the cgMLST profiles from these countries clustered together. Sixty strains were located within a distance of 20 core genes to related genotypes from the publicly available database, and for eighteen isolates, the closest genotype was different by more than 50 loci. Our study showed that WGS based tools are effective in tracing back the geographic origin of infection of patients with unknown travel status, provided that public sequences from the location of the source are available.

Impact of geographical factors on the spread of animal brucellosis in the Republic of Kazakhstan

In Latin and Central America and in most Asian countries, brucellosis remains an insufficiently studied disease. This study aims to determine the national and regional incidence of brucellosis among cattle (cows) and small ruminants (sheep, goats) in the Republic of Kazakhstan, as well as to identify the effect of climatic and geographical factors on the incidence rates. Thematic maps were created in an open geographic information system QGIS version 2.8. in order to identify the natural and socio-economic factors that influence the spread of the disease overlay method was used. Local cluster analysis was used in order to identify additional causes of the disease. Findings show the following values of Pearson correlation between the overall population and the number of animals infected: 0.68 for cows, p ≤ 0.005, and 0.56 for sheep and goats, p ≤ 0.03. Thus, the larger the heard in a given area, the greater likelihood of having brucellosis. Data processing reveals that Kazakhstan has almost twice as many regions good for cattle breeding as regions that are good for the small ruminants farming. The correlation variables for cattle and small ruminants are approximately the same. On the basis of the performed research the author proposes to amend the accepted methodology of epidemiology surveillance by the methods based on spatial (geographical) analysis. It is also proposed to adjust the process of breeding cattle and small ruminants considering the additional health recommendations that take into account the geographical aspects of the spread of the disease.

The epidemiology of Brucellosis in Greece, 2007-2012: a 'One Health' approach

Background

Brucellosis remains a disease that is very difficult to control and eradicate in Greece. Information exchange between the responsible authorities is crucial in order to support public health infrastructure in the sense of the 'One-Health' strategy model.

Methods

The data for 2007-2012 were retrieved from the notifiable diseases system and analysed statistically for correlations between human brucellosis cases and the disease in small ruminants. Disease-related risk factors were also estimated with parallel exploitation mapping software.

Results

In Greece the dominant strain for brucellosis is Brucella melitensis. The average incidence in Greece was estimated to be 1.43/100,000. The majority of human cases were males (67.60%). The age distribution of brucellosis patients differs significantly between men and women. Brucellosis in male patients was related to high risk jobs and animal contact, while brucellosis in females was related to recent consumption of dairy products. Seasonality of the disease was different in relation to the European countries an observation attributed to the traditional customs. There was a statistically significant difference in human brucellosis incidence between the eradication and vaccination zones.

Conclusion

The updated information on brucellosis in Greece revealed differences in seasonality and transmission patterns. A more active cooperation between the involved public health-related sectors should be followed in order to effectively fight brucellosis as there are still foci of brucellosis in Greece.

Economic and health burden of brucellosis in Kazakhstan

Brucellosis is a widespread zoonotic disease considered as an emerging and re-emerging disease with a resulting threat of public health and animal health. Official reports document an animal incidence in Kazakhstan of about 0.6% per year, and the country still registers high number of human cases annually . The main objective of this paper was to evaluate the distribution and economic impact of brucellosis in Kazakhstan. We analysed human disease incidence data obtained from the Government Sanitary & Epidemiological Service with the aim to estimate the burden of disease in terms of disability-adjusted life years (DALYs). We also estimated the economic impact in terms of monetary losses. Additionally, we mapped the geographical distribution of the disease throughout Kazakhstan. In total, 1,334 human cases of brucellosis were registered in 2015 in Kazakhstan that resulted in 713 DALYs. Around $21 million was spent on compensation for animals that had to be slaughtered due to brucellosis, and an additional $24 million was spent on testing animals. Animal brucellosis and human brucellosis occur throughout the whole country, some trends of which are reviewed in this paper. We estimated the burden of the disease and explored possible explanation for high human incidence rates. This paper is the first to estimate the human burden of disease and the economic costs in Kazakhstan. Both of these are substantial.

Distribution of Brucella field strains isolated from livestock, wildlife populations, and humans in Italy from 2007 to 2015

Brucellosis is a major public health problem still prevalent as a neglected endemic zoonosis requiring proactive attention in many communities worldwide. The present study involved analysis of Brucella field strains submitted for typing to the Italian National Reference Laboratory for Brucellosis from 2007 to 2015. Strains were identified at the species and biovar levels by classic and molecular techniques according to the World Organisation for Animal Health Manual. In total, 5,784 strains were typed: 3,089 Brucella abortus (53.4%), 2,497 B. melitensis (43.2%), 10 B. ovis (0.2%), 181 B. suis (3.1%), and 7 B. ceti (0.1%). The 2,981 strains from cattle were typed as B. abortus biovars 1, 3, and 6 (90.1%) and B. melitensis biovar 3 (9.9%). The 318 strains from water buffalo were typed as B. abortus biovars 1, 3 (95.9%) and B. melitensis biovar 3 (4.1%). The 2,279 strains from sheep and goats were typed as B. abortus biovars 1 and 3 (4.3%); B. melitensis biovars 1, 3, (95.3%); and B. ovis (0.4%). The 173 strains from wild boar were typed as B. suis biovar 2 (98.3%) and B. melitensis biovar 3 (1.7%). The 11 strains from pigs were typed as B. suis biovar 2. The 13 strains from humans were typed as B. melitensis biovar 3. The two strains from horses were typed as B. abortus biovar 1, while the seven strains from dolphins were typed as B. ceti. This additional knowledge on the epidemiology of brucellosis in Italy may be useful to formulate policies and strategies for the control and eradication of the disease in animal populations. The animal species affected, biovars typed, geographical origins, and spatial distributions of isolates are herein analyzed and discussed.

A study to identify the practices of the buffalo keepers which inadvertently lead to the spread of brucellosis in Delhi

Background

India has the largest Buffalo population in the world, with every household in rural India owning buffaloes depending upon daily milk requirement – dairy farmers can own between 10 to 70 buffaloes. The health of Indian buffaloes is of economic importance since India is one of the largest buffalo meat exporters in the world, and Indian Buffalo semen is sold in the USA for breeding purposes. However, National Control Program on brucellosis is only active in South India and in Panjab (a North Indian state with high human brucellosis incidence). Our aim was to assess the knowledge and practices of the buffalo keepers of Delhi that make them susceptible to brucellosis.

Results

Amongst all the 11 districts of Delhi, there was 0% awareness about brucellosis and also about the S19 vaccine as the buffalo keepers had never heard of S19 vaccine which is available at minimal cost from Indian Veterinary Research Institute, Bareilly, India. Majority of the respondents drink raw milk, sleep in cattle sheds, do not isolate sick cattle, do not test buffaloes blood for any disease before purchasing them, apply intrauterine medication with bare hands to buffalo after abortion of foetus, never clean their cattle sheds with a disinfectant and believe that they can only acquire skin infections from cattle. All of these habits make them prone to brucellosis. While about 20 to 27% of respondents reported a history of abortions and retained placenta, disposed of the placenta with bare hands, and applied raw milk on cracked lips. It was surprising to note that majority of them never reared small ruminants like sheep and goat with buffaloes or Bos species as they were aware of the rapid spread of disease from small to big ruminants.

Conclusions

We found that buffalo keepers were ignorant of brucellosis, its causative agent, relevant vaccines and that they also involved in high-risk activities. As such, our findings highlight a need for buffalo keepers to be better educated via several awareness camps to minimize human exposure to Brucella in Delhi.

Electronic supplementary material

The online version of this article (10.1186/s12917-018-1670-2) contains supplementary material, which is available to authorized users.

Seropositivity in animals and risk of occupational brucellosis among abattoirs personnel associated with poor work practices and absence of safety policy in Egypt

Background Occupational hazards are the leading cause of morbidity and mortality among abattoirs personnel and animal workers. These hazards result from direct or indirect exposure to potential infection and several distressing events during routine procedures. Objectives To serologically investigate the potential occupational brucellosis hazard at Egyptian abattoirs. To provide an insight on the needed biosafety practices that should be implemented to mitigate the spread of occupational brucellosis among abattoir workers. Methods Two hundred and thirty (n = 230) blood samples were collected from animals in two Egyptian abattoirs. The rose Bengal test was used to evaluate the seroprevalence of Brucella in abattoir animals. A questionnaire was distributed among abattoir personnel to address biosafety gaps and deficiencies as a cause of occupational brucellosis. Results The overall seroprevalence of Brucella using the rose Bengal test was 75.2% in the two targeted abattoirs. It was obvious that there are gaps of malpractices and inconvenient behavior among individuals of the targeted community. Conclusions The current findings reveal the missing role of concerned authorities and lack of written safety policy. The data highlights the need for further research, including isolation and characterization of the causative agents, and reliable epidemiological studies.

An Overview of Brucellosis in Cattle and Humans, and its Serological and Molecular Diagnosis in Control Strategies

Brucellosis is one of the most common contagious and communicable zoonotic diseases with high rates of morbidity and lifetime sterility. There has been a momentous increase over the recent years in intra/interspecific infection rates, due to poor management and limited resources, especially in developing countries. Abortion in the last trimester is a predominant sign, followed by reduced milk yield and high temperature in cattle, while in humans it is characterized by undulant fever, general malaise, and arthritis. While the clinical picture of brucellosis in humans and cattle is not clear and often misleading with the classical serological diagnosis, efforts have been made to overcome the limitations of current serological assays through the development of PCR-based diagnosis. Due to its complex nature, brucellosis remains a serious threat to public health and livestock in developing countries. In this review, we summarized the recent literature, significant advancements, and challenges in the treatment and vaccination against brucellosis, with a special focus on developing countries.

Trend Analysis and Affecting Components of Human Brucellosis Incidence During 2006 to 2016

INTRODUCTION

Brucellosis is communicable between humans and animals. In spite of having an active health care system. Iran is considered as an endemic area and it stands in the fourth place in world ranking. One of the common methods for identifying the disease incidence is a regression analysis. Therefore, the aim of the study was to investigate the trend of brucellosis incidence during 2006 to 2016 and the components affecting such disease.

MATERIALS AND METHODS

This was a trend study which was conducted on the total of 144 brucellosis cases were recorded in the registration software in CDC of Iranian, Ministry of Health. We analyzed the changes in brucellosis incidence during 2006 to 2016 in Juybar province by the join point regression. Moreover, comparing the changes of incidence in one year intervals was also taken into account.

RESULTS

The average age of patients was 18±29 years. About 60% of the patients were men, and 85.4% had used non-pasteurized dairy and meat products. The contact with animals had a significant difference between the two genders (P= 0.006). During 2006 to 2016, brucellosis incidence had a decreased trend about 15%. This trend had a breakpoint in a way that during 2006 to 2008, 66.2% decrease and during 2008 to 2016, 7% increase was observed that none of these annual percentage changes (APC) were statistically significant at p= 0.05. Also, APC of brucellosis incidence in groups below 20 and between 20 to 50 years old had a decrease in a way that in groups under 20, it had 26.7% decrease and it was statistically significant.

CONCLUSION

It is necessary to provide appropriate education training, information on the Human Brucellosis for the young and individuals with high risk professions. Moreover, some health behaviors such as not using non-pasteurized dairy, animals' vaccinations, and awareness of the disease symptoms are needed.

African Lineage Brucella melitensis Isolates from Omani Livestock

Brucellosis is a common livestock disease in the Middle East and North Africa, but remains poorly described in the region both genetically and epidemiologically. Traditionally found in goats and sheep, Brucella melitensis is increasingly recognized as infecting camels. Most studies of brucellosis in camels to date have focused on serological surveys, providing only limited understanding of the molecular epidemiology of circulating strains. We genotyped B. melitensis isolates from Omani camels using whole genome SNP assays and VNTRs to provide context for regional brucellosis cases. We identified a lineage of B. melitensis circulating in camels as well as in goats, sheep, and cattle in Oman. This lineage is genetically distinct from most genotypes from the Arabian Peninsula and from isolates from much of the rest of the Middle East. We then developed diagnostic assays that rapidly identify strains from this lineage. In analyses of genotypes from throughout the region, Omani isolates were genetically most closely related to strains from brucellosis cases in humans and livestock in North Africa. Our findings suggest an African origin for B. melitensis in Oman that has likely occurred through the trade of infected livestock. Moreover, African lineages of B. melitensis appear to be undersampled and consequently are underrepresented in genetic databases for Brucella. As we begin to more fully understand global genomic diversity of B. melitensis, finding and characterizing these unique but widespread lineages is essential. We predict that increased sampling of humans and livestock in Africa will reveal little known diversity in this important zoonotic pathogen.

Impact of measures to control brucellosis on disease characteristics in humans: experience from an endemic region in the Balkans

AIM

To analyze the impact of measures undertaken to control brucellosis in the Republic of Macedonia on demographic, epidemiological and clinical characteristics of the disease in humans.

METHODS

Demographic, epidemiological and clinical characteristics of 340 patients with brucellosis were retrospectively analyzed. Patients were treated at the University Clinic of Infectious Diseases in Skopje during three time periods: 1989-1990 when no national strategy for disease control existed, 2000-2001 when some activities for control were performed and 2011-2014 when an organized and financially supported strategy was accomplished.

RESULTS

A drastic decrease of the number of cases of human brucellosis during the last period when compared to the first two ones (3.9 and 3.3 times lower, respectively) was evident. Patients from the third period were significantly older, with median age 41 years (range 4-73) vs. 31 years (3-77) and 34 years (1-74), respectively (p = .013). There were more males (86.6 vs. 73.6% and 63.2%, respectively, p = .002) and the disease was more often acquired professionally (80.6 vs. 60.1% and 59.2%, respectively, p = .006). Fewer patients from the third period had elevated body temperature either as a symptom (50.7 vs. 73.6% and 69.6%, respectively, p = .003), or as a sign (35.8 vs. 55.4% and 56.8%, respectively, p = .011) and less often exhibited focal forms (40.3 vs. 56.8% and 64.0%, respectively, p = .007).

CONCLUSION

The national strategy for brucellosis control, which included vaccination of small ruminants, resulted in a decrease of human brucellosis cases in the Republic of Macedonia and there was a tendency to milder disease manifestations.

Changing livestock vaccination policy alters the epidemiology of human anthrax, Georgia, 2000-2013

Anthrax is a widely spread zoonotic disease found on nearly every continent. To control the disease in humans and animals, annual livestock vaccination is recommended. However, in 2007, the country of Georgia ended its policy of compulsory annual livestock anthrax vaccination. Our objective was to assess how the epidemiology of human anthrax has evolved from 2000-2013 in Georgia, in the wake of this cessation. We used passive surveillance data on epidemiological surveys of human anthrax case patients. Risk factors and rates of self-reported sources of infection were compared, before and after the change in livestock vaccination policy. We mapped ethnicity-adjusted incidence during the two periods and assessed changes in the spatial pattern of risk. The overall risk of human anthrax increased >5-fold, from 0.7 cases per 100,000 in 2000 to 3.7 cases per 100,000 by 2013. Ethnic disparities in risk became pronounced; from 2000 to 2013, incidence increased >60-fold in Azerbaijanis from 0.35 to 21.1 cases/100,000 Azerbaijanis compared to 0.61 to 1.9 cases/100,000 among ethnic Georgians. Food-borne exposures from purchasing meat increased from 11% in 2000-2006 to 21% in 2007-2013. Spatial analyses revealed a shift from a random pattern of reporting pre-policy change to clustering among district municipalities following the change in policy. Our findings indicate there were unintended human health consequences associated with changing livestock vaccination policy. Following a reduction in the immunizations administered, there was a major shift in the epidemiology of human anthrax in Georgia. Current infection risk is now highest among ethnic minorities. Increased reporting among individuals uncharacteristically at risk for anthrax from foodborne exposures suggests spillover from modes of agricultural production. Given the importance of human-livestock health linkages, careful evaluations of policy need to be undertaken before changes to animal vaccination are made.

Evaluation of recombinant porin (rOmp2a) protein as a potential antigen candidate for serodiagnosis of Human Brucellosis

Background

Brucellosis is an important zoonotic disease caused by different Brucella species and human brucellosis is commonly prevalent in different states of India. Among various Brucella species, B. melitensis is most pathogenic to human and included as category B biothreat which can cause infection through aerosol, cut, wounds in skin and contact with infected animals. The diagnosis of human brucellosis is very important for proper treatment and management of disease as there is no vaccine available for human use. The present study was designed to clone, express and purify immunodominant recombinant omp2a (rOmp2a) porin protein of B. melitensis and to evaluate this new antigen candidate for specific serodiagnosis of human brucellosis by highly sensitive iELISA (indirect enzyme linked immunosorbent assay).

Method

Omp2a gene of B. melitensis 16 M strain was cloned and expressed in pET-SUMO expression system. The recombinant protein was purified under denaturing conditions using 8 M urea. The purified recombinant protein was confirmed by western blotting by reacting with anti-HIS antibody. The sero-reactivity of the recombinant protein was also checked by reacting with antisera of experimentally infected mice with B. melitensis 16 M at different time points. Serodiagnostic potential of recombinant porin antigen was tested against 185 clinical serum samples collected from regions endemic to brucellosis in southern part of India by iELISA. The samples were grouped into five groups. Group 1 contained cultured confirmed positive serum samples of brucellosis (n = 15), group 2 contained sera samples from positive cases of brucellosis previously tested by conventional methods of RBPT (n = 28) and STAT (n = 26), group 3 contained sera samples negative by RBPT(n = 36) and STAT (n = 32), group 4 contained sera samples of other febrile illness and PUO case (n = 35) and group 5 contained confirmed negative sera samples from healthy donors (n = 23).

Result

The rOmp2a was found to be immunoreactive by iELISA and western blotting. The test showed a sensitivity of 93.75% and specificity of 95.83% when tested against 185 serum samples. For determination of statistical significance between experimental groups and control groups, Student’s t test was performed on the data.

Conclusion

Omp2a emerges as a potential antigen candidate for serodiagnosis of human brucellosis.

Brucellosis in a refugee who migrated from Syria to Germany and lessons learnt, 2016

A teenage woman migrating from Syria arrived in May 2015 in Germany. She gave birth to a healthy child in early 2016, but became febrile shortly after delivery. Blood cultures revealed Brucella melitensis. In retrospect, she reported contact with sheep in Syria and recurrent pain in the hip joints over about five months before diagnosis of brucellosis. We discuss consequences for adequate treatment of mother and child as well as for clinical and laboratory management.

Epidemic characteristics, high-risk townships and space-time clusters of human brucellosis in Shanxi Province of China, 2005-2014

Background

Brucellosis, one of the world’s most important zoonosis, has been re-emerging in China. Shanxi Province, located in northern China, where husbandry development has been accelerated in recent years, has a rather high incidence of human brucellosis but drew little attention from the researchers. This study aimed to describe the changing epidemiology of human brucellosis in Shanxi Province from 2005 to 2014 and explore high-risk towns and space-time clusters for elucidating the necessity of decentralizing disease control resource to township level in epidemic regions, particularly in hotspot areas.

Methods

We extracted data from the Chinese National Notifiable Infectious Disease Reporting System to describe the incidence and spatiotemporal distribution of human brucellosis in Shanxi Province. Geographic information system was used to identify townships at high risk for the disease. Space-Time Scan Statistic was applied to detect the space-time clusters of human brucellosis during the past decade.

Results

From 2005 to 2014, a total of 50,002 cases of human brucellosis were recorded in Shanxi, with a male-to-female ratio of 3.9:1. The reported incidence rate increased dramatically from 7.0/100,000 in 2005 to 23.5/100,000 in 2014, with an average annual increase of 14.5%. There were still 33.8% cases delaying diagnosis in 2014. The proportion of the affected towns increased from 31.5% in 2005 to 82.5% in 2014. High-risk towns spread from the north to the center and then south of Shanxi Province, which were basins and adjacent highlands suitable for livestock cultivation. During the past decade, there were 55 space-time clusters of human brucellosis detected in high risk towns; the clusters could happen in any season. Some clusters’ location maintained stable over time.

Conclusions

During the last decade, Shanxi province’s human brucellosis epidemic had been aggravated and high-risk areas concentrated in some towns located in basins and adjacent highlands. Space-time clusters existed and some located steadily over time. Quite a few cases still missed timely diagnosis. Greater resources should be allocated and decentralized to mitigate the momentum of rise and improve the accessibility of prompt diagnosis treatment in the high-risk townships.

Electronic supplementary material

The online version of this article (doi:10.1186/s12879-016-2086-x) contains supplementary material, which is available to authorized users.

Imported brucellosis: A case series and literature review

BACKGROUND

Brucellosis is one of the main neglected zoonotic diseases. Several factors may contribute to the epidemiology of brucellosis. Imported cases, mainly in travellers but also in recently arrived immigrants, and cases associated with imported products, appear to be infrequently reported.

METHODS

Cases of brucellosis diagnosed at a referral unit for imported diseases in Europe were described and a review of the literature on imported cases and cases associated with contaminated imported products was performed.

RESULTS

Most imported cases were associated with traditional risk factors such as travel/consumption of unpasteurized dairy products in endemic countries. Cases associated with importation of food products or infected animals also occurred. Although a lower disease incidence of brucellosis has been reported in developed countries, a higher incidence may still occur in specific populations, as illustrated by cases in Hispanic patients in the USA and in Turkish immigrants in Germany. Imported brucellosis appears to present with similar protean manifestations and both classical and infrequent modes of acquisition are described, leading on occasions to mis-diagnoses and diagnostic delays.

CONCLUSIONS

Importation of Brucella spp. especially into non-endemic areas, or areas which have achieved recent control of both animal and human brucellosis, may have public health repercussions and timely recognition is essential.

Brucellosis Suspicion is the Most Important Criterion for Diagnosis Particularly in Endemic Regions

Introduction:

Brucellosis is a zoonotic infectious disease that remains endemic in developing countries. The purpose of this study is to emphasize the need for considering brucellosis as a diagnosis, since this disease has a high risk of complications among young patients when not treated appropriately.

Methodology:

A total of 88 brucellosis cases with blood cultures that were positive for the pathogen were evaluated retrospectively in this study.

Results:

The patients included 33 males (37.5%) and 55 females (62.5%) with a median age of 8.9 years (range: 5-14 years). A total of 43.1% (n=38) of the cases included occupational exposure to animals as a possible infection source. The consumption of raw milk products, especially cheese, was present in 52.2% (n=46) of the cases. Clinically, 55 of the cases were acute (62.5%), 23 of the cases were subacute (26.2%) and 10 of the cases were chronic (11.3%). The distribution of the joint pain complaints was as follows: 62.5% (n=55) of patients reported hip pain, 22.7% (n=20) of patients reported knee pain, 11.4% (n=10) of patients reported lumbar-back pain and 3.4% (n=3) of patients reported pain in other joints. A total of 59.1% (n=52) of the cases had been examined by another doctor at least once and mistreated.

Conclusion:

Complication rates and the rate of chronic infection increase with delayed diagnosis, and clinical doubt is the most important criterion for diagnosis, particularly in endemic regions.

Human Brucellosis Trends: Re-emergence and Prospects for Control Using a One Health Approach in Azerbaijan (1983-2009)

Brucellosis is one of the most common and widely spread zoonotic diseases in the world. Control of the disease in humans is dependent upon limiting the infection in animals through surveillance and vaccination. Given the dramatic economic and political changes that have taken place in the former Soviet Union, which have limited control, evaluating the status of human brucellosis in former Soviet states is crucial. We assessed annual spatial and temporal trends in the epidemiology of human brucellosis in Azerbaijan, 1983-2009, in conjunction with data from a livestock surveillance and control programme (2002-2009). To analyse trends, we used a combination of segmented regression and spatial analysis. From 1983 to 2009, a total of 11 233 cases of human brucellosis were reported. Up to the mid-1990s, the incidence of human brucellosis showed a pattern of re-emergence, increasing by 25% annually, on average. Following Soviet governance, the incidence rates peaked, increasing by 1.8% annually, on average, and subsequently decreasing by 5% annually, on average, during the period 2002-2009. Despite recent national declines in human incidence, we identified geographic changes in the case distribution characterized by a geographic expansion and an increasing incidence among districts clustered in the south-east, compared to a decrease of elsewhere in the country. Males were consistently, disproportionately afflicted (71%) and incidence was highest in the 15 to 19 age group (18.1 cases/100 000). During the period 2002-2009, >10 million small ruminants were vaccinated with Rev1. Our findings highlight the improving prospects for human brucellosis control following livestock vaccination; however, the disease appears to be re-emerging in south-eastern Azerbaijan. Sustained one health measures are needed to address changing patterns of brucellosis in Azerbaijan and elsewhere in the former Soviet Union.

Human brucellosis occurrences in inner mongolia, China: a spatio-temporal distribution and ecological niche modeling approach

BACKGROUND

Brucellosis is a common zoonotic disease and remains a major burden in both human and domesticated animal populations worldwide. Few geographic studies of human Brucellosis have been conducted, especially in China. Inner Mongolia of China is considered an appropriate area for the study of human Brucellosis due to its provision of a suitable environment for animals most responsible for human Brucellosis outbreaks.

METHODS

The aggregated numbers of human Brucellosis cases from 1951 to 2005 at the municipality level, and the yearly numbers and incidence rates of human Brucellosis cases from 2006 to 2010 at the county level were collected. Geographic Information Systems (GIS), remote sensing (RS) and ecological niche modeling (ENM) were integrated to study the distribution of human Brucellosis cases over 1951-2010.

RESULTS

Results indicate that areas of central and eastern Inner Mongolia provide a long-term suitable environment where human Brucellosis outbreaks have occurred and can be expected to persist. Other areas of northeast China and central Mongolia also contain similar environments.

CONCLUSIONS

This study is the first to combine advanced spatial statistical analysis with environmental modeling techniques when examining human Brucellosis outbreaks and will help to inform decision-making in the field of public health.

Risk factors for occupational brucellosis among veterinary personnel in Turkey

Veterinarians and veterinary technicians are at risk for occupational brucellosis. We described the risk factors of occupational brucellosis among veterinary personnel in Turkey. A multicenter retrospective survey was performed among veterinary personnel who were actively working in the field. Of 712 veterinary personnel, 84 (11.8%) had occupational brucellosis. The median number of years since graduation was 7 (interquartile ranges [IQR], 4-11) years in the occupational brucellosis group, whereas this number was 9 (IQR, 4-16) years in the non-brucellosis group (p<0.001). In multivariable analysis, working in the private sector (odds ratio [OR], 2.8; 95% confidence interval [95% CI], 1.55-5.28, p=0.001), being male (OR, 4.5; 95% CI, 1.05-18.84, p=0.041), number of performed deliveries (OR, 1.01; 95% CI, 1.002-1.02, p=0.014), and injury during Brucella vaccine administration (OR, 5.4; 95% CI, 3.16-9.3, p<0.001) were found to be risk factors for occupational brucellosis. We suggest that all veterinary personnel should be trained on brucellosis and the importance of using personal protective equipment in order to avoid this infection.

Seroprevalence for Coxiella burnetii, Francisella tularensis, Brucella abortus and Brucella melitensis in Austrian adults: a cross-sectional survey among military personnel and civilians

The prevalence of Coxiella burnetii, Francisella tularensis, Brucella abortus, and Brucella melitensis infections in Austria and the exposure risk of military personnel were assessed in an exploratory nationwide cross-sectional seroprevalence survey in 526 healthy adult individuals, 222 of which were soldiers and 304 were civilians. Screening for IgA/IgG antibodies to C. burnetii (Phase I) and IgG/IgM antibodies to C. burnetii (Phase II), and to F. tularensis was done with commercial enzyme-linked immunosorbent assays. To detect antibodies against B. abortus and B. melitensis, an in-house complement fixation test was used. Overall, 11 individuals (2.0%) showed antibodies to C. burnetii, 3 individuals (0.5%) were seropositive for F. tularensis, and one (0.3%) individual was borderline positive. All individuals positive or borderline for F. tularensis tested negative for antibodies against C. burnetii. All individuals tested negative for antibodies against B. melitensis/B. abortus. There were no significant differences between the seroprevalence of C. burnetii and F. tularensis among military personnel and civilians. Our data demonstrate serological evidence of a low rate of exposure to C. burnetii and F. tularensis among the Austrian adult population and military personnel.

Epidemiological features and risk factors associated with the spatial and temporal distribution of human brucellosis in China

Background

Human brucellosis incidence in China has been increasing dramatically since 1999. However, epidemiological features and potential factors underlying the re-emergence of the disease remain less understood.

Methods

Data on human and animal brucellosis cases at the county scale were collected for the year 2004 to 2010. Also collected were environmental and socioeconomic variables. Epidemiological features including spatial and temporal patterns of the disease were characterized, and the potential factors related to the spatial heterogeneity and the temporal trend of were analysed using Poisson regression analysis, Granger causality analysis, and autoregressive distributed lag (ADL) models, respectively.

Results

The epidemic showed a significantly higher spatial correlation with the number of sheep and goats than swine and cattle. The disease was most prevalent in grassland areas with elevation between 800–1,600 meters. The ADL models revealed that local epidemics were correlated with comparatively lower temperatures and less sunshine in winter and spring, with a 1–7 month lag before the epidemic peak in May.

Conclusions

Our findings indicate that human brucellosis tended to occur most commonly in grasslands at moderate elevation where sheep and goats were the predominant livestock, and in years with cooler winter and spring or less sunshine.