Brucella in Tajikistan

One of the most powerful megatrends of our time is urbanization. Urban and peri-urban (UPU) farming is a common practice in many low-income countries because it increases the incomes of families that are often restrained by limited economic resources. However, there is a concern that the growing number of people and livestock living close together in UPU areas will increase the transmission of different zoonotic pathogens such as Brucella. Brucellosis is one of the most common and economically important zoonoses globally and Central Asia represents an area with high incidence among humans and livestock. This thesis aims to assess the occurrence of Brucella among livestock in an UPU area and to elucidate how farmers understand and respond to this zoonosis. The results of this thesis might contribute to raising awareness of how livestock in urban areas can constitute a public health risk if they are infected with Brucella or other zoonoses. The four studies included in this thesis were conducted among small-scale livestock farmers in the UPU region of Dushanbe, the capital of Tajikistan. Blood samples were collected from 904 dairy cows and 667 sheep and goats and analysed with enzyme-linked immunosorbent assay (ELISA). The Brucella seroprevalence was 4.1% among the dairy cows at the herd level and ranged between 1.0% and 15.6% among sheep and goats at the individual level in the four included districts. Furthermore, 564 cow milk samples were analysed for Brucella DNA by IS711-based real-time PCR and 13.7% were found to be positive. All seropositive cows were positive by PCR, but 11.8% of the seronegative cows were also positive by PCR. Further characterization of the Brucella DNA suggests that there is a reservoir of B. abortus in the cattle population and a spillover of B. melitensis from small ruminants to cattle. A knowledge, attitudes and practice study targeting 441 households revealed poor knowledge of brucellosis and several high-risk behaviours, such as consumption of unpasteurized dairy products and not wearing protective clothing when handling potentially infectious materials like aborted foetuses and discharges. Brucella is widespread among the livestock in the UPU area of Dushanbe and this might constitute a serious risk to public health and cause significant economic losses. The discrepancy between serology and PCR results suggests that implementing complementary diagnostic strategies to detect false serological negative individuals might be warranted in Brucella control programmes. Poor knowledge, several high-risk behaviours and a willingness to learn more provide the rationale for developing campaigns to raise awareness of brucellosis and its associated risks among farmers

Bovine leptospirosis in urban and peri-urban dairy farming in low-income countries: a “One Health” issue?

Abstract Global trends in urbanization are increasing the spread of neglected zoonotic infections such as leptospirosis, and reducing the number of human cases of leptospirosis is best accomplished by controlling the infection in the animal reservoir. The aim of this study was to determine the seroprevalence of Leptospira borgpetersenii serovar Hardjo and L. interrogans serovar Hardjo (L. Hardjo) exposure and to assess the associated risk factors for infection in small-scale dairy farming in the urban and peri-urban area of Dushanbe, Tajikistan. The true individual seroprevalence among the dairy cows was 13%, and the level of seroprevalence was positively associated with older cows and with communal grazing practices. The study shows that dairy cows are commonly exposed to L. Hardjo in the study region, and this constitutes a public health risk and demonstrates the importance of including urban and peri-urban areas, where large numbers of humans and animals coexist, when investigating zoonotic infections and when planning and implementing control measures for cattle-associated leptospirosis

Skewness in the literature on infectious livestock diseases in an emerging economy - the case of Vietnam

Livestock production has increased in many emerging economies, but productivity is often substantially impaired by infectious diseases. The first step towards improved livestock health and productivity is to map the presence of livestock diseases. The objective of this review was to summarize studies conducted on such diseases in an emerging economy, Vietnam, and thereby identifying knowledge gaps that may inform the design of surveillance and control programs. Few studies were found to evaluate the distribution of infectious livestock diseases other than avian influenza. Also, many regions with dense livestock populations had received little attention in terms of disease investigation. A large proportion of the studies dealt with zoonoses and food-borne infections which might be due to funding agencies priorities. On the contrary, studies targeting infections that affect livestock and their productivity were few. We think that this limitation in scientific reports on infectious diseases that only affect livestock productivity is a common phenomenon in low and lower middle income countries. More science-based data on such diseases would help policymakers to prioritize which livestock diseases should be subject to animal health programs aimed to support rural livelihoods and economic development

Detection and characterization of Brucella spp. in bovine milk in small-scale urban and peri-urban farming in Tajikistan

Brucellosis is one of the most common zoonoses globally, and Central Asia remains a Brucella hotspot. The World Health Organization classifies brucellosis as a neglected zoonotic disease that is rarely in the spotlight for research and mainly affects poor, marginalized people. Urban and peri-urban farming is a common practice in many low-income countries, and it increases the incomes of families that are often restrained by limited economic resources. However, there is a concern that the growing number of people and livestock living close together in these areas will increase the transmission of zoonotic pathogens such as Brucella. This study investigates the presence of Brucella DNA in bovine milk in the urban and peri-urban area of Dushanbe, Tajikistan. Brucella DNA was detected in 10.3% of 564 cow milk samples by IS711-based real-time PCR. This finding is concerning because consumption of unpasteurized dairy products is common in the region. Furthermore, Brucella DNA was detected in the milk of all seropositive cows, but 8.3% of the seronegative cows also showed the presence of Brucella DNA. In addition, sequence analysis of the rpoB gene suggests that one cow was infected with B. abortus and another cow was most likely infected with B. melitensis. The discrepancies between the serology and real-time PCR results highlight the need to further investigate whether there is a need for implementing complementary diagnostic strategies to detect false serological negative individuals in Brucella surveillance, control, and eradication programmes. Furthermore, vaccination of cattle with S19 in addition to vaccination of small ruminants with Rev 1 might be needed in order to control Brucella infections in the livestock population but further research focusing on the isolation of Brucella is required to obtain a comprehensive understanding of the Brucella spp. circulating among the livestock in this region

How can agricultural research translation projects targeting smallholder production systems be strengthened by using Theory of Change?

Sustainable development of smallholder agriculture production in low and lower middle-income countries are crucial for improving food security. To accommodate this science based evidence needs to bridge with agricultural practices and policy development, which requires coordinated actions and long term strategies involving multiple stakeholders. This paper argues that using a Theory of Change (ToC) approach, with strong emphasis on communication and stakeholder engagement, science based knowledge can be more effectively integrated in agricultural development, but also in policy development. Three projects addressing different challenges within livestock production are used to illustrate the use of and challenges with using a ToC framework. A key for reaching outcome was early involvement of relevant stakeholders in implementing teams and using the flexibility included in the ToC approach from design to implementation

Molecular detection and characterization of Brucella species in raw informally marketed milk from Uganda

This study identified and characterized Brucella species in the informal milk chain in Uganda. A total of 324 cattle bulk milk samples were screened for the genus Brucella by real-time PCR with primers targeting the bcsp31 gene and further characterized by the omp25 gene. Of the samples tested, 6.5% were positive for Brucella species. In the omp25 phylogeny, the study sequences were found to form a separate clade within the branch containing B. abortus sequences. The study shows that informally marketed cattle milk in Uganda is a likely risk factor for human brucellosis and confirms that B. abortus is present in the cattle population. This information is important for potential future control measures, such as vaccination of cattle

Sequence analysis of the <i>RpoB</i>-gene.

<p>Sequence analysis of the <i>RpoB</i>-gene.</p

Ct-values from the IS<i>711</i>-based qPCR of the seronegative individuals (n = 46).

<p>The blue dots represent Ct-values from the first run and the red dots represent Ct-values from the second run.</p

Detection and characterization of <i>Brucella</i> spp. in bovine milk in small-scale urban and peri-urban farming in Tajikistan

<div><p>Brucellosis is one of the most common zoonoses globally, and Central Asia remains a <i>Brucella</i> hotspot. The World Health Organization classifies brucellosis as a neglected zoonotic disease that is rarely in the spotlight for research and mainly affects poor, marginalized people. Urban and peri-urban farming is a common practice in many low-income countries, and it increases the incomes of families that are often restrained by limited economic resources. However, there is a concern that the growing number of people and livestock living close together in these areas will increase the transmission of zoonotic pathogens such as <i>Brucella</i>. This study investigates the presence of <i>Brucella</i> DNA in bovine milk in the urban and peri-urban area of Dushanbe, Tajikistan. <i>Brucella</i> DNA was detected in 10.3% of 564 cow milk samples by IS<i>711</i>-based real-time PCR. This finding is concerning because consumption of unpasteurized dairy products is common in the region. Furthermore, <i>Brucella</i> DNA was detected in the milk of all seropositive cows, but 8.3% of the seronegative cows also showed the presence of <i>Brucella</i> DNA. In addition, sequence analysis of the <i>rpoB</i> gene suggests that one cow was infected with <i>B</i>. <i>abortus</i> and another cow was most likely infected with <i>B</i>. <i>melitensis</i>. The discrepancies between the serology and real-time PCR results highlight the need to further investigate whether there is a need for implementing complementary diagnostic strategies to detect false serological negative individuals in <i>Brucella</i> surveillance, control, and eradication programmes. Furthermore, vaccination of cattle with S19 in addition to vaccination of small ruminants with Rev 1 might be needed in order to control <i>Brucella</i> infections in the livestock population but further research focusing on the isolation of <i>Brucella</i> is required to obtain a comprehensive understanding of the <i>Brucella</i> spp. circulating among the livestock in this region.</p></div