Epidemiology of Brucellosis and Genetic Diversity of Brucella abortus in Kazakhstan

Brucella abortus in Kazakhstan, population structure and comparison with worldwide genetic diversity

Brucella abortus is the main causative agent of brucellosis in cattle, leading to severe economic consequences in agriculture and affecting public health. The zoonotic nature of the infection increases the need to control the spread and dynamics of outbreaks in animals with the incorporation of high resolution genotyping techniques. Based on such methods, B. abortus is currently divided into three clades, A, B, and C. The latter includes subclades C1 and C2. This study presents the results of whole-genome sequencing of 49 B. abortus strains isolated in Kazakhstan between 1947 and 2015 and of 36 B. abortus strains of various geographic origins isolated from 1940 to 2004. In silico Multiple Locus Sequence Typing (MLST) allowed to assign strains from Kazakhstan to subclades C1 and to a much lower extend C2. Whole-genome Single-Nucleotide Polymorphism (wgSNP) analysis of the 46 strains of subclade C1 with strains of worldwide origins showed clustering with strains from neighboring countries, mostly North Caucasia, Western Russia, but also Siberia, China, and Mongolia. One of the three Kazakhstan strains assigned to subclade C2 matched the B. abortus S19 vaccine strain used in cattle, the other two were genetically close to the 104 M vaccine strain. Bayesian phylodynamic analysis dated the introduction of B. abortus subclade C1 into Kazakhstan to the 19th and early 20th centuries. We discuss this observation in view of the history of population migrations from Russia to the Kazakhstan steppes.

One Health evaluation of brucellosis control in Kazakhstan

Brucellosis is one of the main livestock disease risks in Kazakhstan. It's been endemic there since 1930, accounting for over 1300 human cases per annum. The economic loss was 45 million USD in 2015 alone. Since 1952, Kazakhstan has implemented various control strategies with little success. One Health approaches have been suggested to tackle brucellosis, however, there is a lack of evidence for best practices to operationalise One Health in the literature, and methods for implementation are not established. The intention of this study was to introduce the One Health approach during the evaluation phase of the policy cycle. A two-day workshop was organized by the authors to familiarize participants with the evaluation methodology. Twenty-one specialists representing veterinary and public health sector, together with researchers, took part in this study. For two weeks following the workshop, first author conducted individual interviews with workshop participants to obtain individual scorings to assess knowledge integration capacity (One Health-ness). The evaluation results show that there is a lack of knowledge about the perceived damage caused by brucellosis to animal owners and other stakeholders. There is insufficient data available about farmers' practices, interests and motivations, and also data is missing for important transmission processes such as the amount of unsafe dairy consumption. The absence of such data illustrates the extent of the uncertainty to which decision-makers are exposed despite well-elaborated transmission models and supports the importance of co-producing solutions with participatory methods. The results suggest the need for broader involvement of stakeholders. Outputs of this study could help navigate the initial stages of One Health operationalization.

Identification and molecular characterization of Brucella abortus and Brucella melitensis isolated from milk in cattle in Azerbaijan

BACKGROUND

Azerbaijan currently ranks thirteenth in global incidence of human brucellosis, with an estimated annual incidence through 2000 at over 50 cases per million. Brucella melitensis has been isolated from patients and is thought to have been acquired through contact with small ruminants or as a foodborne infection. To reduce the burden of human brucellosis, the Azerbaijani government began in 2002, a nationwide vaccination control campaign in small ruminants. There is serological evidence of bovine brucellosis (presumably due to Brucella abortus) in Azerbaijan, but no prevalence estimates were available when this study started in March 2017. The aim of this study was to isolate and identify Brucella spp. from cow milk in the Ganja region, where brucellosis takes a heavy toll on humans and livestock.

RESULTS

Blood and milk samples were collected from cows (n = 1075) in early lactation (up to 90-days) in farms that had a history of previous positive serological results and abortions. Twenty-two out of 57 milk samples collected from seropositive cows, showed growth on Farrell's media, when incubated with 5% CO₂. Eight additional milk samples showed growth in the absence of CO₂. The classical biotyping classified them as Brucella abortus (22) and Brucella melitensis (8). RT-PCR confirmed that strains belonged to the genus Brucella. MLVA profiles were obtained for DNA extracted from two B. abortus and six B. melitensis strains. While the B. abortus genetic profile was described in the MLVA database, matching the profile of B. abortus strains isolated in East Europe, Central Asia and China, we found a new genotype for the B. melitensis strains isolated in Azerbaijan, clustering with strains belonging to the American clade, rarely identified in the region.

CONCLUSION

Despite the implementation of the vaccination program in small ruminants, our results suggest that spill-over events of B. melitensis from small ruminants to cattle have occurred. However, cattle are likely to be primarily infected with B. abortus, which warranted the implementation of a bovine brucellosis program. Such a program started in fall 2017. In the Ganja region, cattle should be considered as a potential source of B. abortus and B. melitensis for humans.

MLVA typing of Brucella melitensis and B. abortus isolates of animal and human origin from India

Brucellosis is a widely prevalent zoonotic disease of major public health significance. A collection of Brucella melitensis and Brucella abortus field isolates of animal and human origin were subjected to MLVA-15 typing followed by phylogeography studies. The MLVA-15 analysis of B. melitensis (n = 65) field isolates resulted in 48 different profiles. The panel I marker bruce45 was found to be most conserved, while the rest of the panel I markers showed low to moderate length polymorphism. Among the panel II markers, bruce04, bruce16 and bruce30 showed a high discriminatory index. The MLVA-15 typing of 13 B. abortus field isolates revealed 13 different genotypes with panel II markers showing higher discriminatory ability vis-à-vis panel I. The minimum spanning tree analysis (MST) in comparison with isolates from the international database revealed that all B. melitensis and B. abortus isolates from this study belonged to the 'Eastern Mediterranean' and the 'abortus C' lineage, respectively. The MLVA-15 typing could differentiate field isolates of B. abortus and B. melitensis originating from different regions, reaffirming the technique's potential of high resolution and suitability for local epidemiological studies. The MLVA scheme also has the advantage of comparison of local isolates with a worldwide database, allowing for phylogeographical studies.

Emerging diversity and ongoing expansion of the genus Brucella

Remarkable genetic diversity and breadth of host species has been uncovered in the Brucella genus over the past decade, fundamentally changing our concept of what it means to be a Brucella. From ocean fishes and marine mammals, to pond dwelling amphibians, forest foxes, desert rodents, and cave-dwelling bats, Brucella have revealed a variety of previously unknown niches. Classical microbiological techniques have been able to help us classify many of these new strains but at times have limited our ability to see the true relationships among or within species. The closest relatives of Brucella are soil bacteria and the adaptations of Brucella spp. to live intracellularly suggest that the genus has evolved to live in vertebrate hosts. Several recently discovered species appear to have phenotypes that are intermediate between soil bacteria and core Brucella, suggesting that they may represent ancestral traits that were subsequently lost in the traditional species. Remarkably, the broad relationships among Brucella species using a variety of sequence and fragment-based approaches have been upheld when using comparative genomics with whole genomes. Nonetheless, genomes are required for fine-scale resolution of many of the relationships and for understanding the evolutionary history of the genus. We expect that the coming decades will reveal many more hosts and previously unknown diversity in a wide range of environments.

Human brucellosis epidemiology in the pastoral area of Hulun Buir city, Inner Mongolia autonomous region, China, between 2003 and 2018

Human brucellosis represents a serious public health concern in Hulun Buir and requires a comprehensive epidemiologic analysis to define adapted control measures. The present study describes the case numbers, constituent ratios and incidence rate of human brucellosis. Conventional biotyping, that is abortus, melitensis, ovis and suis (AMOS)-PCR and multi-locus variable-number tandem repeat analysis (MLVA) were used to characterize the Brucella strains. Between 2003 and 2018, a total of 23,897 human brucellosis cases were reported, with an incidence rate of 56.03/100,000, which is 20 times higher than the country's average incidence. This incidence rate increased year after year, culminating in 2005 and decreased between 2011 and 2018. Because Hulun Buir relies on a nomadic livestock rearing system, brucellosis spreads easily among different animal species and humans. In Xin Barag Left Banner and Xin Barag Right Banner, the incidence rates were, respectively, 226.54/100,000 and 199.10/100,000, exceeding those observed in other areas. Most of the cases occurred in the 25- to 45-year-old group, accounting for 65.74% of the cases (15,709/23,897), and among farmers, accounting for 66.71% (15,942/23,897). The male to female incidence ratio was 2.67:1. The higher incidence in younger people and the large gender ratio reflected the unique traditional production and lifestyle of nomads. Most reported cases were observed from April to June, indicating that more than 40% of the cases were related to the delivery of domestic livestock. The biotyping showed that the 44 isolated strains were all B. melitensis, including 12 Brucella melitensis biovar (bv) 1 and 32 B. melitensis bv. 3. The strains displayed a genetic similarity of 80%-100%. Our hypothesis is that human brucellosis outbreak in this region may be originating from a limited source of infection, so further investigation is necessary. The epidemic situation of human brucellosis in Hulun Buir is extremely serious, strengthened surveillance and control in animals' brucellosis should be priority.

Brucella melitensis, a latent "travel bacterium," continual spread and expansion from Northern to Southern China and its relationship to worldwide lineages

Brucellosis caused by Brucella melitensis is considered to be one of the most important zoonotic diseases in China. In this study, Conventional bio-typing, MLVA (multiple locus variable-number tandem repeat analysis), and WGS (whole-genome sequencing)-SNP (single nucleotide polymorphism) were used to study the genetic similarity of B. melitensis in northern and southern China and analyze its relationship with worldwide lineages. Currently, the distribution of species/biovars of B. melitensis has obviously changed, and B. melitensis has become the dominant species in southern regions of China. Strains from the southern had a common geographic origin with strains from the northern. Many MLVA-16 events were shared in the genotypes of the southern and northern strains, suggest that genotypic movement occurred from north to south. Based on WGS-SNP analysis, strains from different provinces were closely related and may have descended from one common ancestor, suggests that the southern strains originated from northern China. These data indicate that B. melitensis is a latent “travel bacterium” that spread and expanded from North China to South China. Moreover, B. melitensis strains from China are also genetically related to strains from other Asian regions (Kazakhstan, Russia, Mongolia, and India). The movement of infected sheep and their products requires control.

High incidence of human brucellosis in a rural Pastoralist community in Kenya, 2015

Background

Brucellosis occurs globally with highly variable incidence in humans from very low in North America and Western Europe to high in the Middle East and Asia. There are few data in Sub-Saharan Africa. This study estimated the incidence of human brucellosis in a pastoralist community in Kenya.

Methods

Between February 2015 and January 2016, we enrolled persons living in randomly selected households in Kajiado County. Free health care was offered at three facilities in the study area. Those who met the study clinical case definition completed a standardized questionnaire on demographics, clinical history and presentation. A blood sample was collected and tested by Rose Bengal test (RBT), then later tested at the Kenya Medical Research Institute laboratory for Brucella IgG and IgM by ELISA. Those who tested positive by both RBT and ELISA (IgG or IgM antibodies) were classified as confirmed while those that only tested positive for IgG or IgM antibodies were classified as probable. Further, sera were tested by polymerase chain reaction using a TaqMan Array Card (TAC) for a panel of pathogens causing AFI including Brucella spp. Annual incidence of brucellosis was calculated as the number of confirmed cases in one year/total number in the study population.

Results

We enrolled a cohort of 4746 persons in 804 households. Over half (52.3%) were males and the median age was 18 years (Interquartile range (IQR) 9 months– 32 years). A total of 236 patients were enrolled at three health facilities; 64% were females and the median age was 40.5 years (IQR 28–53 years). Thirty-nine (16.5%) were positive for Brucella antibodies by IgG ELISA, 5/236 (2.1%) by IgM ELISA and 4/236 (1.7%) by RBT. Ten percent (22/217) were positive by TAC. We confirmed four (1.7%) brucellosis cases giving an annual incidence of 84/100,000 persons/year (95% CI 82, 87). The incidence did not significantly vary by gender, age and location of residence.

Conclusion

We report a high incidence of brucellosis in humans among members of this pastoralist community. Brucellosis was the most common cause of febrile illness in this community.

Brucellosis is a bacterial disease that affects both humans and animals. Humans get infected via ingestion of unpasteurized animal products from infected animals and direct contact during animal abortions and deliveries. Infected animals shed bacteria for life through milk and during deliveries posing a risk to those with occupational exposure to infected animals. As such, human disease is disproportionately high in regions with high prevalence of animal brucellosis. While human brucellosis is distributed globally, incidence is low in North America and Western Europe and high in Asia and the Middle East where the disease is endemic. Data from Africa are scarce. We set out to estimate the incidence of brucellosis in a pastoralist community with documented high Brucella sero-prevalence in humans and livestock. We followed up a cohort of 804 households for one year and tested household members who became ill in three designated health facilities. We estimated an incidence of 84 cases per 100,000 persons per year in this community. We also found that Brucella was the most common pathogen among persons who had febrile illness highlighting the importance of this pathogen in this rural pastoralist community. No brucellosis intervention measures were being implemented.

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.

Arranging The Questionnaire To Identify Brucellosis Risk Factors In Western Kazakhstan

Background ― In some Kazakhstan regions, the epidemic situation on brucellosis remains tense, despite the observed trend to decrease in the incidence: 5.5 per 100,000 population by 2018 vs. 6.2 in 2017. The article aims at presenting the steps of preparing the brucellosis questionnaire to identify infection risk factors. Methods ― A questionnaire is developed based on the Health Belief Model to arrange interviews among the adult population of the Aktobe region. Stages of the drafting process included: 1) review of relevant literature sources; 2) assessment of the target audience to calculate N (number of interviewees); 3) development of the questionnaire itself; 4) testing the tool in focus-groups; 5) validation through Cronbach’s alpha (α) calculation to reach the internal consistency of the questionnaire; 6) final editing of the survey tool. The Cronbach’s alpha was calculated using the item-analysis in the SPSS Modeler.v.25. Results ― The designed questionnaire consisted of the three domains with twenty-two questions of the semi-closed type and underwent testing in the focus-group of ninety-eight livestock owners. A preliminary analysis revealed five items with unsatisfactory mean values, which were either modified or deleted so that the α resulted in 0.71 (moderately reliable). The adjusted tool eventually contained seventeen items (questions). Conclusion ― A simple design and adequate validation of the survey tool should facilitate information on population awareness of the clinical symptoms and paths of brucellosis infection transmission. Data on accepted practice on caring for livestock in private households across the region also become available for analysis owing to the presented questionnaire.

Genetic variation of Brucella isolates at strain level in Egypt

In this study, Multiple Locus Variable Number Tandem Repeat Analysis (MLVA‐16) was performed on 18 Brucella isolates identified bacteriologically and molecularly (AMOS‐PCR) as Brucella abortus (n = 6) and Brucella melitensis (n = 12). This was aimed to study the genetic association among some Egyptian Brucella genotypes isolated during the period from 2002 to 2013 along with the global genotypes database. MLVA‐16 analysis for B. melitensis and B. abortus strains illustrates a total of 11, and 3 genotypes with 10 and 1 singleton genotypes, respectively. B. melitensis strains displayed greater markers diversity by VNTRs analysis of the 16 loci than B. abortus and this was attributed mainly to the diverging in panel 2B markers. B. melitensis genotype M4_Fayoum_Giza (3,5,3,13,1,1,3,3,8,21,8,7,5,9,5,3) was the only predominated genotype circulating between two different governorates. The most common B. abortus genotype, GT A3_Dakahlia (4,5,4,12,2,2,3,3,6,21,8,4,4,3,4,4), was present in three identical isolates. In phylogeny, Egyptian B. abortus bv1 genotypes were closely related to East Asian strain (for the first time), Western Mediterranean and Americas clonal lineages. B. melitensis local genotypes exhibit a genetic relatedness mostly to Western Mediterranean clonal lineage and one strain of Eastern Mediterranean clonal lineage. In conclusion, the geographic location is not the only factor stands behind the high genetic similarity of the Egyptian Brucella genotypes. These low variations may be a result of a stepwise mutational event of the most variable loci from a very limited number of ancestors especially during the transmission through non‐preference hosts. The authors encourage the authorities in charge to establish pre‐movement testing to reduce the risk of brucellosis spread.

Genetic Diversity of Brucella melitensis in Kazakhstan in Relation to World-Wide Diversity

We describe the genetic diversity of 1327 Brucella strains from human patients in Kazakhstan using multiple-locus variable-number tandem repeat (VNTR) analysis (MLVA). All strains were assigned to the Brucella melitensis East Mediterranean group and clustered into 16 MLVA11 genotypes, nine of which are reported for the first time. MLVA11 genotype 116 predominates (86.8%) and is present all over Kazakhstan indicating existence and temporary preservation of a “founder effect” among B. melitensis strains circulating in Central Eurasia. The diversity pattern observed in humans is highly similar to the pattern previously reported in animals. The diversity observed by MLVA suggested that the epidemiological status of brucellosis in Kazakhstan is the result of the introduction of a few lineages, which have subsequently diversified at the most unstable tandem repeat loci. This investigation will allow to select the most relevant strains for testing these hypotheses via whole genome sequencing and to subsequently adjust the genotyping scheme to the Kazakhstan epidemiological situation.

Phenotypic and genotypic characteristics of Brucella isolates from the Republic of Kazakhstan

The purposes of this study were to determine phenotypic and genotypic characteristics of Brucella isolates from the Republic of Kazakhstan and to determine their biotype. The focus was laid on culture-morphological, biochemical, and biological properties of 59 Brucella isolates from primary cultures. Material was isolated from blood and tissue of serum-positive killed, dead diseased, or aborted domestic cattle from different regions of Kazakhstan where brucellosis is a common problem. Multiple-locus variable number tandem repeat analysis (MLVA) of all strains, isolated in different regions, has shown that Brucella isolates from the epizootic form two clusters. Based on the comparison with strains available in the MLVA database, B. abortus 0015/B is alike the B. abortus strains isolated from Italy and Portugal. B. melitensis 0016/B isolated from the Almaty region fits the third cluster and is alike the B. melitensis strains isolated from humans in Turkey, China, and Portugal. More than 90% of the overall B. abortus samples were isolated from the northern regions of the East and West Kazakhstan, while B. melitensis strains were registered in the southeast Kazakhstan. The most frequently recorded B. abortus biovar is biovar 3. The most frequently recorded B. melitensis biovars are biovars 1 and 3. SIGNIFICANCE AND IMPACT OF STUDY: These results contribute to a better understanding of the geographic pattern of Brucella infection in Kazakh cattle also important for developing the specific control measures. The results of current research can be used for creating a gene bank of Brucella strains circulating in Kazakhstan for producing diagnostic and therapeutic agents. The research material will be used to solve the problems of genetic characterization of Brucella species and to establish the phylogenetic relationships of strains.

Risk factors for human brucellosis among a pastoralist community in South-West Kenya, 2015

Objective

Brucellosis is one of the top five priority zoonosis in Kenya because of the socio-economic burden of the disease, especially among traditional, livestock keeping communities. We conducted a 1 year, hospital based, unmatched case–control study to determine risk factors for brucellosis among Maasai pastoralists of Kajiado County in 2016. A case was defined by a clinical criteria; fever or history of fever and two clinical signs suggestive of brucellosis and a positive competitive enzyme-linked immunosorbent assay test (c-ELISA). A control was defined as patients visiting the study facility with negative c-ELISA. Unconditional logistic regression was used to study association between exposure variables and brucellosis using odds ratios (OR) and 95% confidence intervals (CI).

Results

Forty-three cases and 86 controls were recruited from a population of 4792 individuals in 801 households. The mean age for the cases was 48.7 years while that of the controls was 37.6 years. The dominant gender for both cases (62.7%) and controls (58.1%) groups was female. Regular consumption of un-boiled raw milk and assisting animals in delivery were significantly associated with brucellosis by OR 7.7 (95% CI 1.5–40.1) and OR 3.7 (95% CI 1.1–13.5), respectively.

On the Role of Short-Term Animal Movements on the Persistence of Brucellosis

Short-term animal movements play an integral role in the transmission and control of zoonotic infections such as brucellosis, in communal farming zones where animal movements are highly uncontrolled. Such movements need to be incorporated in models that aim at informing animal managers effective ways to control the spread of zoonotic diseases. We developed, analyzed and simulated a two-patch mathematical model for brucellosis transmission that incorporates short-term animal mobility. We computed the basic reproduction number and demonstrated that it is a sharp threshold for disease dynamics. In particular, we demonstrated that, when the basic reproduction number is less than unity, then the disease dies out. However, if the basic reproduction number is greater than unity, the disease persists. Meanwhile, we applied optimal control theory to the proposed model with the aim of exploring the cost-effectiveness of different culling strategies. The results demonstrate that animal mobility plays an important role in shaping optimal control strategy.

On the dynamics of brucellosis infection in bison population with vertical transmission and culling

We introduce a new mathematical modeling framework that seek to improve our quantitative understanding of the influence of chronic brucellosis and culling control on brucellosis dynamics in periodic and non-periodic environments. We conduct both epidemic and endemic analysis, with a focus on the threshold dynamics characterized by the basic reproduction numbers. In addition, we also perform an optimal control study to explore optimal culling strategy in periodic and non-periodic environment.

Antimicrobial susceptibility of Brucella melitensis in Kazakhstan

Background

Kazakhstan belongs to countries with a high level of brucellosis among humans and farm animals. Although antibiotic therapy is the main way to treat acute brucellosis in humans there is still little information on a circulation of the antibiotic-resistant Brucella strains in the Central Eurasia. In this article we describe an occurrence of the drug resistance of Brucella melitensis isolates in Kazakhstan which is among the largest countries of the region.

Methods

Susceptibilities to tetracyclin, gentamycin, doxycyclin, streptomycin and rifampicin were investigated in 329 clinical isolates of Brucella melitensis using E-test method.

Results

All isolates were susceptible to streptomycin, tetracycline and doxycycline. 97.3% of the Brucella isolates were susceptible to gentamycin, although only 37.4% of isolates were susceptible to rifampicin. 21.9% of isolates had intermediate resistance, and 26.4% of isolates were resistant to this antibacterial drug.

Conclusion

Isolates of Brucella melitensis circulating in Kazakhstan are susceptible to streptomycin, doxicyclin, tetracyclin and gentamycin. At the same time the resistance to rifampicin is widespread, almost half of the isolates were rifampicin-resistant (including the intermediate resistance).

Genotyping of Brucella melitensis and Brucella abortus strains in Kazakhstan using MLVA-15

Currently, although the prevalence of brucellosis in Kazakhstan remains high, there are limited data available on the genetic diversity of circulating Brucella strains. Here, MLVA was employed to genotype a panel of 102 Brucella isolates collected from eight Kazakh regions and neighboring countries (Russia, Kyrgyzstan) during the period 1935-2017. MLVA-11 analysis classified 64 B. abortus strains into genotypes 72, 82, 331, 71, 341 and 69, while one genotype was novel, having no correspondence within the MLVA international database. MLVA-11 analysis of 37 B. melitensis strains showed 100% identity with genotypes 116, 114 and 11. One B. suis strain was classified into genotype 33. Phylogeography based on MLVA-15 demonstrated that all B. abortus and B. melitensis strains belonged to "Abortus C" and "East Mediterranean" lineages, respectively. B. abortus strains from Kazakhstan and Russia resulted genetically related to Portuguese, Brazilian and US isolates, suggesting ancient spread of these lineages from Europe westwards to South America and eastwards to Turkey, Russia and Asia. Most of Kazakh B. melitensis isolates were related to strains circulating in China, likely due to long-term trading partnerships between the two countries. In fine-scale MLVA-15 analysis, 17 B. abortus and 12 B. melitensis genotypes were identified; among them 12 are novel. Interestingly, epidemiological information supporting molecular data were retrieved for two clusters within the B. abortus group, thus proving that MLVA is an appropriate tool for effective traceback analyses. Our findings suggest that molecular genotyping should be applied systematically to support control plans for eradication of brucellosis in Kazakhstan.