Surra is an animal trypanosomosis, caused by infection with Trypanosoma evansi and leading to severe economic loss due to mortality and morbidity. Compared to tsetse-transmitted animal trypanosomoses, little attention is given to the epidemiology and control of surra. Understanding its epidemiology is a first step in local and global efforts to control the disease. We conducted a systematic review and meta-analysis of published studies on distribution, host ranges and prevalence of T. evansi infection. Four electronic databases were searched for publications on T. evansi that met our inclusion criteria for the systematic review. Subsets of publications were subjected to meta-analysis for the pooled prevalence of T. evansi in various hosts as determined by multiple detection methods. A total of 272 references published between 1906–2017 were included. Trypanosoma evansi was reported from 48 countries; largely confined to Africa and Asia with publications on natural T. evansi infections from 77% (n = 48) of countries, contrasting with seven countries in South America, and four in Europe where T. evansi is not endemic but was imported with infected animals. Although surra is a notifiable disease, many countries do not report surra cases to OIE. Trypanosoma evansi was mainly reported from dromedary camels in Africa and the Middle East, water buffaloes, cattle, dogs and horses in East and Southeast Asia. In South America, the acute form of the disease was reported in horses and dogs. Surra was also reported in a wide range of wild animals. Some rare human cases occurred in India and Vietnam. Meta-analysis on a subset of 165 publications indicated pooled prevalence of T. evansi in domestic animals ranging from 14–31%, 6–28% and 2–9% using respectively antibody detection, molecular and parasitological tests, with camels as the most affected, followed by buffalo and cattle. This study illustrates that T. evansi affects a wide range of domestic and wild animals in Africa, Asia and South America with highest prevalence observed in dromedary camels. For successful control of T. evansi, both locally and globally, the role of wild animals in the epidemiology of surra needs further investigation.

Staphylococcus species cause mastitis and wound infection in livestock and food poisoning in humans through ingestion of contaminated foods, including meat and dairy products. They are evolving pathogens in that they readily acquire drug resistance, and multiple drug-resistant (MDR) isolates are increasing in human and veterinary healthcare. Therefore, this study was conducted to evaluate the prevalence of Staphylococci and their drug resistance in dairy farms and abattoir settings of Addis Ababa. In this cross-sectional study, 193 samples of milk, meat, equipment and humans working in the dairy farms and abattoir were collected (dairy farms = 72 and abattoir sources = 121). Staphylococcus isolation and identification at the species level was done according to ISO-6888-3 using biochemical characteristics. An antimicrobial susceptibility test was conducted for 43 of the isolates using 15 antimicrobial agents commonly used for humans and livestock by the Kirby Bauer disk diffusion method following CLSI guidelines. Staphylococcus organism were isolated from 92 (47.7%) of the total 193 samples, 50% in the dairy farms and 46.3% in the abattoir. The isolated species were S. aureus (n = 31; 16.1%), S. intermedius (n = 21; 10.9%), S. hyicus (n = 16; 8.3%), and coagulase negative Staphylococcus (CNS) (n = 24; 12.4%). Gentamycin was effective drug as all isolates (n = 43; 100%) were susceptible to it and followed by kanamycin (n = 39; 90.7%). However, the majority of the isolates showed resistance to penicillin-G (95.3%), nalidixic acid (88.4%), cloxacillin (79.1%), vancomycin (65.1%) and cefoxitin (55.8%). Of the 15 S. aureus tested for drug susceptibility, 73.3% of them were phenotypically resistant to vancomycin (VRSA) and all of the 15 isolates showed multi-drug resistance (MDR) to >3 drugs. Also, all of the tested CNS (100%), S. hyicus (100%) and the majority of S. intermedius isolates (88.9%) developed MDR. Alarmingly, the Staphylococcus isolates circulating in the dairy farms and abattoir in the study area harbor MDR. High level of Staphylococcus species isolation from personnel and equipment besides food (meat and milk) samples in dairy farms and abattoir settings reveals that the hygiene practice in the dairy farm and abattoir is substandard. Prudent drug use and improved hygienic practice is recommended in the dairy farms and abattoir to safeguard the public from the risk of acquiring infections and MDR pathogenic Staphylococcus.

Ethiopia set an ambitious masterplan to increase chicken meat and egg production from 2015 to 2020. Poultry breeding, multiplication and distribution centers in the country have received executive order to import, amplify and distribute commercial chickens to end users. The biosecurity and the pathogen fauna of the centers have not been evaluated as to whether the centers could implement the mission effectively without any risk. Thus, the aim of this study was to evaluate the biosecurity practices and the pathogen prevalence, risk factors and their antimicrobial resistance (AMR) using Salmonella as case study. Routine farm workers of the centers were interviewed about the different management (biosecurity) practices using a checklist. Samples (n = 270) from different sources consisting of chicken’s cloacal swab (n = 244), personnel hand swab (n = 9) and bedding (n = 17) were collected from three chicken multiplication centers. Standard bacteriological methods were used for the isolation of Salmonella. Disk diffusion method was used for drug sensitivity testing. Antimicrobials were often over prescribed without confirming the cause of ill health and without susceptibility testing. The general biosecurity and flock management practices were substandard. Salmonella was isolated from 45 (16.7%) of the 270 samples. Its prevalence was significantly (p<0.05) associated with location of the multiplication center, 27% at Bonga and 10.6% at Hawassa. Sample type was also significantly (p<0.05) affected in that it was higher in the bedding (35.3%) and personnel hand swabs (33.3%) than in the chicken cloaca (14.8%), which demonstrates the poor biosecurity and personnel hygienic practices in the centers. All of the 45 isolates (100%) exhibited resistance to kanamycin and sulfamethoxazole-trimethoprim, nalidixic acid (97.8%), ampicillin (97.8%), cefoxitin (97.8%), streptomycin (97.8%) tetracycline (97.8%), chloramphenicol (91.3%), ciprofloxacin (31.1%), and gentamicin (0%). Alarmingly, 42 isolates (93.4%) exhibited multidrug resistance (MDR) to ≥ 8 drugs and all 45 isolates had resistance to ≥ 3 drugs. The high rate of Salmonella isolation from (i) bedding, (ii) personnel hand swabs (iii) chickens, (iv) presence of more MDR isolates, (v) coupled with poor biosecurity practices in the centers could pose a risk for spreading of pathogens and drug resistant genes to the smallholder chicken producers and the public. We conclude that the poultry breeding, multiplication and distribution centers in Ethiopia, as they stand currently, seem to be a source of pathogens and AMR isolates at least for Salmonella. Therefore, strict biosecurity, personnel safety, prudent drug use, regular monitoring and traceability of Salmonella serotypes or genotypes and AMR are recommended.

Salmonellosis is a leading cause of foodborne illnesses in humans with cattle being one of the reservoirs for Salmonella. We estimated a pooled prevalence of Salmonella in apparently healthy cattle and examined serotype diversity through systematic review and meta-analysis of studies published between 2000 and 2017. Peer reviewed publications reporting the prevalence of Salmonella in cattle were searched through five electronic databases (PubMed, Google scholar, Agricola, Scopus, CAB direct) and through manual search. We obtained 71 publications with 75 datasets consisting a total of 52,766 animals examined and 5,010 Salmonella positive cattle from 29 countries in six continents (except from Antarctica). Pooled prevalence of Salmonella in cattle was 9% (95% confidence interval: 7–11%). Significantly high heterogeneity (I² = 98.7%, P < 0.01) was observed among all studies as well as within continents. Prevalence varied from 2% (Europe) to 16% (North America). Overall, 143 different serotypes were reported with the most diverse serotypes being reported from Africa (76 different serotypes) followed by North America (49 serotypes). The 10 most frequently reported serotypes (Montevideo, Typhimurium, Kentucky, Meleagridis, Anatum, Cerro, Mbandaka, Muenster, Newport, and Senftenberg) accounted for 65% of the isolates for which specific serotype information was reported. Salmonella Montevideo and S. Dublin are the most frequently reported serotypes in North America and Europe, respectively, while S. Typhimurium was the most frequent in Africa, Asia and Australasia. Our results indicated variability both in the prevalence and serotype diversity of Salmonella in cattle across continents. Although all Salmonella serotypes are potentially pathogenic to humans, five (Montevideo, Typhimurium, Anatum, Mbandaka, and Newport) of the top 10 serotypes identified in this study are among the serotypes most commonly associated with clinical illnesses in humans.

Mastitis is the most prevalent and economically important disease caused by different etiological agents, which leads to increased somatic cell count (SCC) and low milk quality. Treating mastitis cases with antimicrobials is essential to reduce SCC and improve milk quality. Non-prudent use of antimicrobials in dairy farms increased the development of antimicrobial resistant bacteria. This study’s objectives were (1) to isolate and identify etiological agents of mastitis and (2) to determine antimicrobial resistance profiles of bacterial isolates. A total of 174 quarter milk samples from 151 cows with high SCC and clinical mastitis from 34 dairy farms in Tennessee, Kentucky, and Mississippi were collected. Bacterial causative agents were determined by bacteriological and biochemical tests. The antimicrobial resistance of bacterial isolates against 10 commonly used antimicrobials was tested. A total of 193 bacteria consisting of six bacterial species, which include Staphylococcus aureus, Streptococcus uberis, Streptococcus dysgalactiae, Escherichia coli, Klebsiella oxytoca and Klebsiella pneumoniae were isolated. Staphylococcus aureus was the predominant isolate followed by Strep. spp., E. coli, and Klebsiella spp. Results of this study showed that Gram-negatives (E. coli and Klebsiella spp.) were more resistant than Gram-positives (Staph. aureus and Streptococcus spp.). Continuous antimicrobial resistance testing and identification of reservoirs of resistance traits in dairy farms are essential to implement proper mitigation measures.

Staphylococcus aureus is a frequent and major contagious mastitis bacterial pathogen. The antibiotic treatment cure rates vary considerably from 4% to 92%. Staphylococcus aureus readily becomes resistant to antibiotics, resulting in persistent noncurable intramammary infection that usually results in culling of infected animals. Because of its notorious ability to acquire resistance to the commonly used as well as last resort antimicrobials such as methicillin and vancomycin and the development of multidrug-resistant strains, antimicrobial resistance (AMR) in S. aureus is of paramount importance in human medicine. The objective of this study was to evaluate the prevalence of AMR and genetic diversity of S. aureus isolates from milk of dairy cattle. Staphylococcus aureus isolates (n = 239) from 33 dairy farms in Tennessee were tested against 10 antimicrobials by broth microdilution method using the Sensititer system. Genetic diversity of resistant isolates was evaluated by pulsed-field gel electrophoresis (PFGE). Overall, AMR of the S. aureus isolates varied from as low as 1.3% for ceftiofur to as high as 25% for sulfadimethoxine. Out of 239 S. aureus isolates, 82 (34.3%) of them were resistant to at least 1 of the 10 antimicrobials. The AMR isolates belonged to two major PFGE types, indicating the presence of dominant clonal patterns among the resistant isolates. In general, there was a variation of prevalence of AMR within and among farms over time, with an increasing trend in tetracycline resistance. Judicious use of antimicrobials in dairy cattle farms can reduce the development of antimicrobial-resistant S. aureus.