Seroprevalence of Brucellosis in Occupationally Exposed Humans in Quetta, Pakistan

Brucellosis seroprevalence in dairy cattle in China during 2008–2018: A systematic review and meta-analysis

The incidence of zoonoses in Korea has increased recently. However, the study of high risk groups for zoonoses has not been conducted to date in Korea. Thus, we did this study to obtain data on brucellosis among slaughterhouse workers in Korea. We evaluated the structure of slaughterhouses and the process of slaughtering by reviewing the relevant literature and doing field studies. We visited 73 slaughterhouses and 62 residual products handle houses across the country. In addition, we conducted a questionnaire survey of the work activities, and obtained blood samples in order to determine the seroprevalence and risk factors of brucellosis. The titers of brucellosis antibodies were measured using the standard tube agglutination test (SAT). We diagnosed subjects as seropositive for Brucellosis if the titers were more than 1:160. The data collected was evaluated using SPSS ver. 17.0. We included 1,503 subjects and obtained 1,482 blood samples among them: 849 workers involved in slaughtering, 351 handlers of residual products, 190 inspectors and their assistants, and 92 grading testers and their assistants. The seroprevalence of brucellosis among the slaughterhouse workers was 0.8% (95% CI=0.4-1.5). Broken down, the seroprevalence of brucellosis among the workers involved in slaughtering was 0.7% (95% CI=0.3-1.6), the handlers of residual products was 1.7% (95% CI=0.7-3.9) respectively. Risk factors for contracting brucellosis among slaughterhouse workers were being splashed with cattle blood around the mouth, cattle secretions around the body and not putting on protective apron while at work. An educational program is needed for high risk groups on zoonoses about the prevention of infection. Thus, effective working guidelines for workers who participate in the slaughter of animals must be developed in order to protect them from zoonoses.

Simple SummaryBrucellosis caused by Brucella spp. is transmitted by direct or indirect contact with infected animals or their secretions and through the consumption of infected animal meat and unpasteurized milk/milk products. Brucellosis is classified as one of the top neglected zoonosis by the World Health Organization (WHO), and despite this, it does not attract the appropriate attention it requires from both the Federal and State ministries of health in Nigeria. Currently, there is a lack of coordinated national data on the prevalence and distribution of human and animal brucellosis. Thus, published research works between 2001 and 2021 were studied based on set criteria to estimate the burden and distribution of brucellosis in Nigeria. The results of the national seroprevalence of human and animal brucellosis were 17.6% (554/3144) and 13.3% (8547/64,435), respectively. Specifically, 15.8% (7178/45,363) seroprevalence of brucellosis was recorded in northern Nigeria as against 8.7% (1902/21,740) in the southern part. Brucella abortus, B. melitensis, B. suis, and B. canis were reported in 27 of the 36 states. Improved sanitation at the abattoirs, use of personal protective equipment by animal handlers, vaccination of animals against brucellosis, and ranching of animals to curb the spread of the disease should be paramount to all stakeholders.The global burden of human and animal brucellosis remains enormous. The disease, which is endemic in Nigeria, lacks appropriate attention and national data. This review estimated the burden and distribution of human and animal brucellosis in Nigeria in the last twenty-one years (2001–2021). Publications reporting the detection of brucellosis in Nigeria were sorted from different search engines, including PubMed, ResearchGate, Scopus, and Google Scholar, to generate data on its prevalence, spatial distribution, and predisposing factors. The results of the national seroprevalence of human and animal brucellosis as revealed in this study were 17.6% (554/3144) and 13.3% (8547/64,435), respectively. Specifically, 15.8% (7178/45,363) seroprevalence of brucellosis was recorded in northern Nigeria as against 8.7% (1902/21,740) seroprevalence in the southern part. It also indicated that 78.7% of the detected brucellae were un-typed. The Brucella species detected were B. abortus (15.2%), B. melitensis (4%), B. suis (1.8%), and B. canis (0.4%). This study revealed that brucellosis is endemic in Nigeria. Culture and molecular methods for detecting brucellosis and reports on antimicrobial susceptibility testing remain a conjecture. This review will help researchers redirect their research focus and serve as a guide for policymakers on measures for managing brucellosis in Nigeria.

Background: Brucellosis is a common emerging and re-emerging zoonotic disease in animals and humans globally. It has drastically changed over the past decade because of various risk factors, including the drastic growth of animal husbandry, socioeconomic, political, and global trade, travel, and immigration. Domestic animals are a natural reservoir of Brucella spp., and animal-to-human transmission occurs through the consumption of raw milk and milk products; however, it is recognized as an occupational disease of veterinarians, animal farmers, and abattoir workers as they handle infected animals and aborted fetuses or placentae. Surveillance and epidemiology of domestic animals and humans are urgently needed to eradicate this zoonotic disease effectively nationally and globally. Although serological data on the prevalence of brucellosis in different domestic animals have been reported, studies on the seroprevalence of human brucellosis are very limited in Bangladesh. Objective: A cross-sectional survey was conducted to estimate seroprevalence and risk factors of human brucellosis among high-risk individuals of Mymensingh. Materials and Methods: Bood samples were collected from 182 animal handlers, and sera were separated by standard laboratory method. They were tested using the Rose Bengal plate test (RBT) and confirmed for brucellosis by enzyme-linked immunosorbent assay (i-ELISA). Results: The overall seroprevalence of brucellosis was found to be 2.20%. Individuals over 30 years old have a higher seroprevalence of brucellosis (9.09%), while those aged 20-30 have the lowest (0.72%). Only males were found to be seropositive for brucellosis (2.5%). The study revealed that artificial inseminators had the highest prevalence of human brucellosis (10.0%), while animal owners had the lowest (5.0%). The study found that human brucellosis is most prevalent in individuals with contact durations of 10 to 20 years (6.38%), while the lowest prevalence is seen in individuals less than 10 years. The study found that the seroprevalence of human brucellosis was higher (5.80%) in individuals who consumed raw milk than those who did not. Conclusions: This study has recorded the prevalence of brucellosis at low levels among high-risk individuals in the study area. The surveillance reports on human brucellosis are still limited in South Asia, including Bangladesh. Animals are carriers of Brucella, and infection in humans is often transmitted by consumption of raw milk and milk products and contact with aborted animals. Therefore, human brucellosis could be eradicated nationally and globally by eradicating animal brucellosis, which requires a ‘One Health’ strategy. Epidemiological surveillance and prevention of zoonotic brucellosis in South Asian countries is a great challenge due to weak interdisciplinary collaboration on the ‘One Health’ concept and low socio-economic status. However, avoiding risky practices like consuming raw milk and milk products and handling aborted materials without protective equipment are required, along with control of this disease in animals.

A cross-sectional study was carried out in Jimma town and Chora Botor district of Jimma zone from February 2014 to May 2014 to determine seroprevalence and risk factors of brucellosis in cattle. A total of 348 blood samples (174 each from zebu and crossbreed) were collected. The sera were separated and screened by Rose Bengal plate test (RBPT), and positive sera were retested by complement fixation test (CFT) for confirmation. The overall seroprevalence of bovine brucellosis was 1.4 and 0.3% as tested by RBPT and CFT, respectively. The seroprevalence of bovine brucellosis in indigenous and crossbreed cattle was 1.1 and 0.6% and 1.7 and 0% using RBPT and CFT, respectively. Retained fetal membrane was the only risk factor found to be significantly associated with seropositivity of brucellosis in this study (p = 0.019). The overall seroprevalence of brucellosis was very low. However, due to the zoonotic and economic importance of the disease, prevention and control measures are required to stop further spread of the disease. To effectively implement this, the One Health (OH) is the most constructive approach we recommend.

A cross-sectional study was carried out from October 2008- March 2009 to determine the sero-prevalence of bovine brucellosis in four districts of Jijjiga Zone, eastern Ethiopia. Purposive sampling technique was employed to select the four districts and nine peasant associations (PAs). A total of 435 blood samples were collected from cattle of 6 or more months of age with no history of previous vaccination against brucellosis. All serum samples were initially screened by Rose-Bengal- Plate Test (RBPT) and those positive reactors to RBPT (n=8) were further tested by complement fixation test (CFT) for confirmation. Out of the 8 RBPT positive sera 6 were found to be positive to CFT. Accordingly, the overall seroprevalence of bovine brucellosis in Jijjiga Zone was 1.38% (6/435). The seroprevalence of bovine brucellosis in the four districts namely Awbare, Harshi, Kebribayah and Fafan districtes were 0.78%, 2.91%, 2.06% and 0%, respectively. Statistically there is no significant deference among the four districts (÷2 = 3.37, df = 3, P = 0.268). The study also revealed absence of significant statistical variation in the seroprevalence of brucellosis in different age and sex groups of the study animals (P > 0.05). Result of this study showed that the seroprevalence of bovine brucellosis in the study area is low. However, it is highly likely that the disease spreads in unaffected animals and herds given the extensive production system prevailing in the area which may allow contact of animals during grazing and at watering points. The public in general and high risk group in particular should be made aware of the zoonotic importance of bovine brucellosis.

A cross sectional study was carried out from October 2008 to April 2009 to determine the sero-prevalence of brucellosis in small ruminants in and around Bahir Dar, northwest Ethiopia. The sampling method used was purposive sampling technique for districts and simple random for the study animals. A total of 500 serum samples (270 from sheep and 230 from goats) were collected from extensive management system with no history of vaccination. All serum samples were initially screened by Rose-Bengal-Plate Test (RBPT) and positive reactors to RBPT (n=6) were further tested by complement fixation test (CFT) for confirmation. Accordingly, the overall prevalence of brucellosis in small ruminants was 0.4 % (2/500). Rose Bengal Plate Test detected 6 (1.2%) of the samples as seropositive. Up on further testing by CFT only 2 (0.4%) were positive which were adult goats. The seroprevalence of brucellosis was found higher in females (0.4%) than males (0%). Although seropositive animals are low in number, it was found out that animals more than 1 year of age were more affected than others. The result of the present study revealed that the seroprevalence of small ruminant brucellosis in the study area was very low. However, the existence of the disease in the study area has possible risk of spread in the future. Accordingly, elimination of positive seroreactors has been recommended to control the spread of brucellosis in these species of animals.

Brucellosis is a highly infectious bacterial zoonotic disease that carries substantial economic and public health implications, especially within pastoral and agropastoral communities in Ethiopia. A cross‐sectional study was employed from December 2022 to October 2023 to estimate the seroprevalence of brucellosis among camels and goats and to assess community awareness towards its zoonotic importance in selected districts of Afar, Ethiopia. A total of 528 serum samples were sequentially tested using the Rose Bengal plate test (RBPT) and the competitive enzyme‐linked immunosorbent assay (c‐ELISA). A questionnaire survey was administered to camel and goat owners to assess community awareness of zoonotic importance of brucellosis. Collected data were entered, coded, and analyzed using SPSS version 27 software. In the current study areas, the overall seroprevalence of camels’ and goats’ brucellosis, based on RBPT as well as c‐ELISA, was found to be 3.03% and 2.27% with 95% CI; 0.48–5.53. Moreover, the seroprevalence of brucellosis among the species level was 3.75% (n = 9/240) in camels and 2.43% (n = 7/288) in goats in the study districts. The survey indicated that 85% of the pastoral community in the study areas is unaware of the zoonotic significance of camel and goat brucellosis. Moreover, almost 88% of pastoralists and agropastoralists in the study districts were found to handle abortions and retained placentas with their barehands. The calculated Kappa (κ) statistic was found to be 0.853, indicating an “almost perfect” level of agreement between the RBPT and ELISA serological tests. An increased seroprevalence of camel and goat brucellosis in pastoral communities, along with prevailing animal husbandry practices and raw food consumption habits, suggests that brucellosis could pose a significant public health threat in the study areas. This highlights the need for awareness creation to educate farmers about the disease and promote safer practices, ultimately helping to protect the community from brucellosis.

BackgroundBrucellosis is a contagious bacterial disease, which affects domestic animals, humans, and wildlife in Ethiopia and other countries.MethodsA cross-sectional study design using a simple random sampling technique was conducted in Diga, Guto, Gida, and Sibu Sire districts of East Wollega Zone, Western Oromia, from November 2019 to July 2020 to determine the prevalence of bovine brucellosis and identify associated risk factors. A lottery method was used during serum collection and risk factors identified during interview.ResultsA total of 1152 serum samples were collected from cattle of 6 months age and above. Serum samples were tested by enzyme linked immunosorbent assay (I-ELISA). An overall seroprevalence of brucellosis was 1.82% (21/1152). Statically significant variation (P<0.05) in seroprevalence of bovine brucellosis was recorded among potential risk factors such as breed [P≤0.05; OR:8.905; CI:1.568–50.573], parity [P≤0.05; OR:0.017; CI:0.042–5.195], retained fetal membrane [P≤0.001; OR:0.018; CI:0.00–2.169], and abortion history [P≤0.001; OR:0.030; CI:0.004–0.212]. Conversely, seroprevalence variations in sex, district, villages, body condition score, and age were statistically insignificant (P>0.05).ConclusionThe current study revealed bovine brucellosis is posing a threat to livestock with no strict control and prevention scheme in place. Therefore, public awareness creation about the zoonotic importance of the disease is crucial and the Government should establish legislation, support, control, and prevention of the disease recommended.

BackgroundThe seroprevalence and risk factors of bovine brucellosis were studied at animal and herd level using a combination of culture, serological and molecular methods. The study was conducted in 253 randomly selected cattle herds of the Potohar plateau, Pakistan from which a total of 2709 serum (1462 cattle and 1247 buffaloes) and 2330 milk (1168 cattle and 1162 buffaloes) samples were collected. Data on risk factors associated with seroprevalence of brucellosis were collected through interviews using questionnaires. Univariable and multivariable random effects logistic regression models were used for identifying important risk factors at animal and herd levels.ResultsOne hundred and seventy (6.3%) samples and 47 (18.6%) herds were seropositive for brucellosis by Rose Bengal Plate test. Variations in seroprevalence were observed across the different sampling sites. At animal level, sex, species and stock replacement were found to be potential risk factors for brucellosis. At herd level, herd size (≥9 animals) and insemination method used were important risk factors. The presence of Brucella DNA was confirmed with a real-time polymerase chain reaction assay (qRT-PCR) in 52.4% out of 170 serological positive samples. In total, 156 (6.7%) milk samples were positive by milk ring test. B. abortus biovar 1 was cultured from 5 positive milk samples.ConclusionThis study shows that the seroprevalence of bovine brucellosis is high in some regions in Pakistan. Prevalence was associated with herd size, abortion history, insemination methods used, age, sex and stock replacement methods. The infected animal may act as source of infection for other animals and for humans. The development of control strategies for bovine brucellosis through implementation of continuous surveillance and education programs in Pakistan is warranted.

Brucellosis is a zoonotic disease of considerable economic and public health significance worldwide. No information available about brucellosis status in the Gomole and Elewaye districts, Borana pastoral area, southern Ethiopia. Hence, aim this study was to estimate the seroprevalence of brucellosis in small ruminants and the associated risk factors in the study districts. A cross-sectional study design was conducted to estimate the seroprevalence of brucellosis in small ruminants and to assess the associated risk factors. The study animals were managed under extensive pastoral production system. Small ruminants above 6 months of age were included in the study. Approximately 10 mL of aseptic blood samples were collected from the jugular vein, and sera were extracted and stored at −20°C until the laboratory tests were conducted. All sera samples were screened using the rose Bengal plate test (RBPT). Those sera positive in RBPT were subjected to indirect enzyme-linked immunosorbent assay (iELISA) for confirmation. From 648 sera samples (i.e., 264 sheep and 384 goats), 40 (6.2%) were seropositive in iELISA, and the seroprevalence of brucellosis in sheep and goats was 3.4% and 8.1%, respectively. The seroprevalence of brucellosis was significantly higher in goats (odds ratio [OR], 2.15; p &lt; 0.05) than in sheep, animals aged ≥ 5 years (OR, 11.23; p &lt; 0.05), in good body condition (OR, 2.92; p &lt; 0.05) and in larger flock sizes, ≥40 animals, (OR, 9.52; p &lt; 0.05). The recorded seroprevalence was higher, and control measures, such as testing and culling of seropositive animals, could reduce the problem.

The Global Seroprevalence of Equine Brucellosis: A Systematic Review and Meta-analysis Based on Publications From 1990 to 2022.

Objective: This study was conducted to determine the seroprevalence and typing of brucellosis in lactating cows in some dairy farms in Kuwait. Materials and methods: A total of 4671 serum samples were collected from 4671 apparently healthy lactating cows comprising of 486 from Al-Wafra, 348 from Al-Kabed and 3837 from Al-Salebia areas. The sera were tested by Buffered Acidified Plate Antigen Test (BAPAT), Rose Bengal Plate Test (RBPT) and Complement Fixation Test (CFT) for the presence of brucellosis. Besides, Milk Ring Test (MRT) was done with 60 milk samples collected from 60 lactating cows comprising 18 from Al-Wafra, 5 from Al-Kabed and 37 from Al-Salebia areas. The stomach content of aborted feti were tested for typing of Brucella organism by using specific antisera. Results: The results showed that the overall seroprevalence of bovine brucellosis was 339 (7.25%) by BAPAT, 332 (7.1%) by RBPT, and 329 (7.04%) by CFT. The results revealed that, 42 (8.6%), 5 (1.4%) and 292 (7.6%) sera were positive for brucellosis by BAPAT in the cows of Al-Wafra, Al-Kabed and Al-Salebia areas, respectively. Whereas, their respective number and seroreactive cases by RBPT were 39 (8.02%), 5 (1.4%) and 288 (7.4%). Similarly, as confirmatory test by CFT, the number and seroreactive cases in these areas were 39 (8.02%), 5 (1.4%) and 285 (7.46%). MRT revealed that the average positive case was 61.67% (59.46% in Al-Wafra; 60% in Al-Kabed and 66.6% in Al-Salebia). Two Brucella isolates could be recovered from the stomach content of the two aborted feti and typed as Brucella melitensis biovar 2. Conclusion: Brucellosis is prevalent among lactating cows in Kuwait. This indicates the potential role of these dairy animals in disseminating and spread of such zoonosis to human. Considering public health significance, appropriate preventive measures are suggestive for combating brucellosis in Kuwait.

Cross-sectional study was conducted in Yabello and Dire districts of Borena zone Oromia regional state, Ethiopia to estimate sero-prevalence of small ruminant and human Brucellosis. Sero-survey was applied to the target population of 228 small ruminants and 86 humans. The sera samples were collected from small ruminants (sheep and goats) and humans for serological analysis of brucellosis. Samples were serially tested by RBPT and positive samples were finally confirmed by c-ELISA. The overall sero-prevalence of brucellosis were 8.8% (95% CI: 5.4-13.2) and 25.6% (95% CI: 16.8-36.1) in small ruminants and humans respectively. There was a statistically significant variation in Brucella infection (p<0.05) in humans. The higher prevalence recorded in elders. The highest recorded in small ruminant sampled from large flock size and ewes with a retained fetal membrane. These results provide evidence of the importance of brucellosis in humans and small ruminants in the study area. Overall, the existence of brucellosis, community daily practice and uncontrolled movement of animals and livelihood nature of pastoralists suggest the need for farther investigation of brucellosis in humans and animals. Furthermore, awareness creation or public health education on zoonotic importance of brucellosis and prevention techniques should be imparted continuously in pastoral communities.

Brucellosis is one of the most neglected zoonotic diseases in the world. It affects all age groups and both sexes. A cross-sectional study was conducted from December 2019 to May 2020 to estimate the seroprevalence and assess the potential risk factors of brucellosis among dairy cow owners and dairy farmworkers, and assess their knowledge, attitudes, and practices in selected sites in the central highlands of Oromia, Ethiopia. A structured interview question was administered to 284 respondents, and only 166 of them volunteered to give a blood sample. Most respondents had limited knowledge of brucellosis (93.3%), zoonotic diseases transmitted by handling animal delivery (88%), and consuming raw milk and other animal products (90.0%). Accordingly, 149 blood samples from animal owners and 17 farmworkers were collected for serological testing. The serum samples collected were initially screened using the Rose Bengal Plate test, and the Complement Fixation test was used as a confirmatory test. The overall seroprevalence of zoonotic brucellosis was 1.2% (95%CI: 0.32–4.27). There was a statistically significant association of human brucellosis with human housing (OR = 1.8, p = 0.002), contact with aborted fetus (OR = 21.19, p = 0.017), drinking raw milk from non-aborted (OR = 24.99, p = 0.012), aborted (OR = 5.72, 0.019), and retained fetal membrane (OR = 4.22, p = 0.029) cows. In conclusion, the present study revealed that the seroprevalence of brucellosis in the study area was low. Public awareness among animal owners, farm and animal health workers on the transmission and health hazards of brucellosis needs to be addressed through community training. Implementing one health approach between veterinary and medical health professionals must be strengthened.