PhD Student, University of Melbourne
Understanding the prevalence of brucellosis in camels in a pastoral community in Ethiopia.
Pastoralists are people whose livelihoods depend on animals for food, transport and income, and due to the close contact with their animals, they are at a higher risk of diseases which can be transmitted from animals to humans including brucellosis. Brucellosis is a disease which is not studied in detail in the pastoralist community and affects livestock and camels and is also transmissible to humans causing infections in humans. We conducted a study in a pastoralist community in the Eastern part of Ethiopia to determine the distribution of the disease in the community. In this study, we also looked at the perception and awareness of the community towards the disease and modes of transmission. Our study involved collection of blood from camels to look for markers of infection and conducted in-depth interviews with the camel owners on their awareness of the disease and its transmission methods. Our results show that 1.53% of the sampled camels were positive for the disease. The disease was more prevalent in female camels than male camels and was more prevalent in female camels with a history of abortion. In addition, most of the owners reported that they had no awareness about the disease and we identified drinking raw/unpasteurized camel milk as a contributing factor for transmission of the disease from camels to humans. The fact that the disease affects female camels more than male camels has an impact on the productivity of the herd and ultimately affects the income of the family. As females are responsible for taking care of the camels and the household, it puts an additional economic burden on the livelihood of the family. Our findings show that brucellosis is an important and established disease in the study area and is a potential public health hazard in the pastoralist community. In conclusion, brucellosis creates a great deal of suffering both in health and financial terms in poor and vulnerable communities and effort should be directed to better understand the genetics, and distribution of the disease and recommend effective control methods.
Abstract: To assess seroprevalences of Brucella and C. burnetii in pastoral livestock in southeast Ethiopia, a cross-sectional study was carried out in three livestock species (cattle, camels and goats). The study was conducted from July 2008 to August 2010, and eight pastoral associations (PAs) from the selected districts were included in the study. Sera from a total of 1830 animals, comprising 862 cattle, 458 camels and 510 goats were screened initially with Rose Bengal plate test (RBPT) for Brucella. All RBPT positive and 25% of randomly selected negative sera were further tested by ELISA. These comprise a total of 460 animals (211 cattle, 102 camels and 147 goats). Out of sera from total of 1830 animals, 20% were randomly selected (180 cattle, 90 camels and 98 goats) and tested for C. burnetii using ELISA. The seroprevalences of Brucella was 1.4% (95% confidence interval (CI), 0.8-2.6), 0.9% (95% CI, 0.3-2.7)b and 9.6% (95% CI, 5.2-17.1) in cattle, camels and goats, respectively. Goats and older animals were at higher risk of infection (OR=7.3, 95% CI, 2.8-19.1) and (OR=1.7 95% CI, 0.9-2.9), respectively. Out of 98 RBPT negative camel sera, 12.0% were positive for ELISA. The seroprevalences of C. burnetii were 31.6% (95% CI, 24.7-39.5), 90.0% (95% CI, 81.8-94.7) and 54.2% (95% CI, 46.1-62.1) in cattle, camels and goats, respectively. We found positive animals for C. burnetii test in all tested PAs for all animal species. Being camel and older animal was a risk factor for infection (OR=19.0, 95% CI, 8.9-41.2) and (OR=3.6, 95% CI, 2.0-6.6), respectively. High seropositivity of C. burnetii in all livestock species tested and higher seropositive in goats for Brucella, implies risks of human infection by both diseases. Thus, merit necessity of further study of both diseases in animals and humans in the area.
Pub.: 19 Dec '13, Pinned: 23 Mar '18
Abstract: Brucellosis is a highly contagious zoonosis caused by bacteria of the genus Brucella and affecting domestic and wild mammals. In this paper, the bacteriological and serological evidence of brucellosis in Sub-Saharan Africa (SSA) and its epidemiological characteristics are discussed. The tools available for the diagnosis and treatment of human brucellosis and for the diagnosis and control of animal brucellosis and their applicability in the context of SSA are presented and gaps identified. These gaps concern mostly the need for simpler and more affordable antimicrobial treatments against human brucellosis, the development of a B. melitensis vaccine that could circumvent the drawbacks of the currently available Rev 1 vaccine, and the investigation of serological diagnostic tests for camel brucellosis and wildlife. Strategies for the implementation of animal vaccination are also discussed.
Pub.: 10 Nov '15, Pinned: 23 Mar '18
Abstract: Brucellosis is the most frequent zoonosis reported in Qatar, mainly related to exposure to infected camels. An outbreak of human brucellosis in 14 members of a family living in a rural area in Qatar is reported herein. Clinical, epidemiological and laboratory results from all 14 patients with Brucella and 12 non-confirmed family members were collected from files. All patients reported fever for a maximum of 14 days, associated with arthralgia (6 patients), weakness (4 patients), headache (4 patients), diarrhea (2 patients) and abdominal pain (2 patients). The median age of the patients was 10 years and that of non-cases was 16 years, with a predominance of males (92.9%). Elevated levels of transaminases were observed in patients. A mixed infection caused by Brucella abortus and Brucella melitensis was identified by blood culture and serology. The source of the infection was the milk of an infected camel. The outbreak of brucellosis melitensis/abortus related to the consumption of camel milk constitutes a gap in the prevention and control of the potential sources of brucellosis in animal farms. Proper control and education of the population are required.
Pub.: 23 Jan '16, Pinned: 23 Mar '18
Abstract: Brucellosis is a zoonosis of economic importance that reduces productivity in livestock enterprises as it induces abortion in infected animals. A study was designed aimed at detecting Brucella in blood and lymph node specimens from camels by the use of real-time PCR in Iran. Sample collection and DNA extraction were done on blood (n = 135) and lymph node (n = 135) samples collected from 135 camels (abattoir survey) from both sexes at various ages in different seasons. The real-time PCR for species differentiation was based on unique genetic loci of B. melitensis and B. abortus. The regions were chosen for the construction of primers and TaqMan® probes for species differentiation: BMEII0466 gene for B. melitensis and Bru-Ab2_0168 gene for B. abortus. Brucella spp. were identified in 18 (13.33%) blood samples and 4 (2.97%) lymph node samples. This method showed to be effective in detecting B. abortus and B. melitensis in blood and lymph samples respectively. Brucella abortus was detected in 3 (2.22%) blood samples but was however, not detected in the lymph node samples. Brucella melitensis was only observed in 4 (2.97%) lymph node samples. Significant differences were observed on the blood prevalence of unknown Brucella spp. in different age groups and seasons (P < 0.05). However, there were no significant differences observed on the prevalence of B. abortus, B. melitensis, unknown Brucella spp. in different age groups, sex and seasons (P > 0.05). Therefore, Brucella was detected in apparent healthy camels slaughtered at an abattoir in Iran and this recommends the significance of the detection of Brucella in camels, since the infected camels appear to be healthy.
Pub.: 23 Dec '15, Pinned: 23 Mar '18
Abstract: The camel is a multipurpose animal with a huge productive potential. Camel milk is a key food in arid and semi-arid areas of the African and Asian countries. The quality of milk is influenced by different bacteria present in milk. This study was conducted to evaluate total bacterial content in raw camel milk along the market chain in Fafen zone, Ethiopian Somali Regional State.One hundred twenty-six raw camel milk samples were collected from Gursum (47.1 %) and Babile (52.9 %) districts. The three sampling levels included were udder (14.7 %), milking bucket (29.4 %) and market (55.9 %). Milk samples were analyzed for total bacterial counts (TBC) and coliform counts (CC). Furthermore, major pathogens were isolated and identified.108 (85.7 %) of raw camel milk samples demonstrated bacterial contamination. The overall mean TBC and CC of contaminated raw camel milk samples was 4.75 ± 0.17 and 4.03 ± 0.26 log CFU/ml, respectively. TBC increased from udder to market level and was higher in Gursum compared to Babile district (P < 0.05). Around 38.9 % of TBCs and 88.2 % CCs in contaminated raw camel milk samples were in the range considered unsafe for human utility. Staphylococcus spp. (89.8 %), Streptococcus spp. (53.7 %), E. coli (31.5 %), Salmonella spp. (17.6 %), Klebsiella spp. (5.6 %) and Enterobacter spp. (5.6 %) were the major bacterial microorganisms isolated.The majority of the bacterial isolates in this study showed high incidence in market as compared to production level. These results indicate a lack of compliance with good production practices and hygiene at milking, transportation and market of raw camel milk.
Pub.: 26 May '16, Pinned: 23 Mar '18
Abstract: The search for ideal brucellosis vaccines remains active today. Currently, no licensed human or canine anti-brucellosis vaccines are available. In bovines, the most successful vaccine (S19) is only used in calves, as adult vaccination results in orchitis in male, prolonged infection, and possible abortion complications in pregnant female cattle. Another widely deployed vaccine (RB51) has a low protective efficacy. An ideal vaccine should exhibit a safe profile as well as enhance protective efficacy. However, currently available vaccines exhibit one or more major drawbacks. Smooth live attenuated vaccines suffer shortcomings such as residual virulence and serodiagnostic interference. Inactivated vaccines, in general, confer relatively low levels of protection. Recent developments to improve brucellosis vaccines include generation of knockout mutants by targeting genes involved in metabolism, virulence, and the lipopolysaccharide synthesis pathway, as well as generation of DNA vaccines, mucosal vaccines, and live vectored vaccines, have all produced varying degrees of success. Herein, we briefly review the bacteriology, pathogenesis, immunological implications, candidate vaccines, vaccinations, and models related to Brucella.
Pub.: 02 Sep '17, Pinned: 23 Mar '18
Abstract: Human brucellosis is prevalent in both rural and urban Uganda, yet most cases of the disease in humans go unnoticed and untreated because of inaccurate diagnosis, which is often due to the disease not manifesting in any symptoms. This study was undertaken to describe trends in laboratory-confirmed human brucellosis cases at three health facilities in pastoralist communities in South-western, Uganda.Data were collected retrospectively to describe trends of brucellosis over a 10-year period (2003-2012), and supplemented with a prospective study, which was conducted from January to December 2013. Two public health facilities and a private clinic that have diagnostic laboratories were selected for these studies. Annual prevalence was calculated and linearly plotted to observe trends of the disease at the health facilities. A modified Poisson regression model was used to estimate the risk ratio (RR) and 95 % confidence intervals (CIs) to determine the association between brucellosis and independent variables using the robust error variance.A total of 9,177 persons with suspected brucellosis were identified in the retrospective study, of which 1,318 (14.4 %) were confirmed cases. Brucellosis cases peaked during the months of April and June, as observed in nearly all of the years of the study, while the most noticeable annual increase (11-23 %) was observed from 2010 to 2012. In the prospective study, there were 610 suspected patients at two public health facilities. Of these, 194 (31.8 %) were positive for brucellosis. Respondents aged 45-60 years (RR = 0.50; CI: 0.29-0.84) and those that tested positive for typhoid (RR = 0.68; CI: 0.52-0.89) were less likely to have brucellosis.With the noticeable increase in prevalence from 2010 to 2012, diagnosis of both brucellosis and typhoid is important for early detection, and for raising public awareness on methods for preventing brucellosis in this setting.
Pub.: 05 Sep '15, Pinned: 23 Mar '18
Abstract: Diarrhea and deaths in new-born camel calves were noticed by veterinary investigators and pastoralist in Saudi Arabia to be very high. Hence, it is thought to be necessary to investigate this problem from the virological and bacteriological point of view. The role of pathogenic bacteria and viruses in six different towns of North Province (Al-Assafia, Arar, Domat Aljandal, Hail, Skaka and Khoa) in Saudi Arabia was studied. Survey was conducted in diarrheic camel calves aged 12 months or younger. In our study calf diarrhea was reported in 184 out of 2308 camels examined clinically during one year, the prevalence of diarrhea was found to be 8.0% in calves ranging from one month to one year. In the present study group A rotavirus and Brucella abortus were detected in 14.7% and 8.98%, respectively, using ELISA technique. Escherichia coli was isolated from diarrheic calf camel (58.2%) 99/170 samples during dry and wet season. Salmonella spp. and Enterococcus spp. were detected in 12% and 8.8% of the specimens, respectively. In this study enterotoxogenic E. coli (ET E. coli) was isolated from 7% of diarrheic camel, which indicates the strong correlation between the camel calf diarrhea and the detection of enterotoxogenic E. coli. This study represented the first report for the detection of group A rotavirus and B. abortus antigen and antibodies in calf camels in Saudi Arabia. It is recommended that the disease should be controlled by vaccination in calf camels.
Pub.: 01 Jan '12, Pinned: 23 Mar '18
Abstract: A cross-sectional study was carried out in four districts of the Afar region in Ethiopia to determine the prevalence of brucellosis in camels, and to identify risky practices that would facilitate the transmission of zoonoses to humans. This study involved testing 461 camels and interviewing 120 livestock owners. The modified Rose Bengal plate test (mRBPT) and complement fixation test (CFT) were used as screening and confirmatory tests, respectively. SPSS 16 was used to analyze the overall prevalence and potential risk factors for seropositivity, using a multivariable logistic regression analysis.In the camel herds tested, 5.4% had antibodies against Brucella species, and the district level seroprevalence ranged from 11.7% to 15.5% in camels. The logistic regression model for camels in a herd size > 20 animals (OR = 2.8; 95% CI: 1.16-6.62) and greater than four years of age (OR = 4.9; 95% CI: 1.45-16.82) showed a higher risk of infection when compared to small herds and those ≤ 4 years old. The questionnaire survey revealed that most respondents did not know about the transmission of zoonotic diseases, and that their practices could potentially facilitate the transmission of zoonotic pathogens.The results of this study revealed that camel brucellosis is prevalent in the study areas. Therefore, there is a need for implementing control measures and increasing public awareness in the prevention methods of brucellosis.
Pub.: 19 Dec '13, Pinned: 23 Mar '18
Abstract: In many developing countries of Asia and Africa, camels are one of the most important sources of income for the nomadic population. With increasing urbanization, camel milk and meat have gained a wider market and commercialization and consumption of camel products are on the rise. Camel brucellosis can be encountered in all camel rearing countries with exception of Australia. High animal and herd prevalences have been reported from numerous countries, which not only pose a continuous risk for human infection, but also increase the spread of infection through uncontrolled trade of clinically inconspicuous animals. This short review aims at providing an overview on diagnostic investigations, as well as the public health and economic impact of brucellosis in old world camels.
Pub.: 26 Dec '12, Pinned: 23 Mar '18