Prevalence, Risk Factors, and Molecular Detection of Campylobacter in Farmed Cattle of Selected Districts in Bangladesh.

A cross-sectional survey was conducted in selected districts of Bangladesh to estimate prevalence, risk factors, and molecular detection of Campylobacter isolates from 540 farmed cattle of 90 herds. As an individual sample, 540 feces, and as a pooled sample, 180 milk samples, 90 feed samples, 90 water samples, 90 manure samples, and 90 animal attendants' hand-rinse water were collected and tested via culture, biochemical, and molecular assays. A pretested semi-structured questionnaire was used to collect herd-level data on risk factors with the herd owners. The herd-level data on risk factors were analyzed through univariate and multivariate analyses, and a p-value <0.05 was considered statistically significant for all analyses. Overall, farm-level prevalence of bovine Campylobacter was enumerated to be 53.3% (95% confidence interval [CI]: 42.5-63.9%). The feces sample was found to be a high level of contamination of 30.9% (95% CI: 27-35%) followed by the manure swab (pooled) at 15.6% (95% CI: 8.8-24.7%). Campylobacter jejuni was documented as an abundant species (12.6%), followed by Campylobacter coli (5.1%), and Campylobacter fetus (0.3%). Older farms (>5 years of age), no/minimum cleaning and disinfection practices, along with animal roaming outside of the farm, were documented as significant risk factors for farm-level Campylobacter occurrence. Evidence-based control measures need to be taken through stringent biosecurity and hygienic measurement to lessen the load of the Campylobacter pathogen in the farm environment and prevent further transmission to animals and humans.

Salmonella Gallinarum in Small-Scale Commercial Layer Flocks: Occurrence, Molecular Diversity and Antibiogram.

Salmonella Gallinarum is one of the most important bacterial pathogens associated with diminished egg production in poultry. The aim of this study was to understand the occurrence, molecular traits and antimicrobial resistance patterns of Salmonella Gallinarum strains isolated from small-scale commercial layer flocks with low level biosecurity standards in Bangladesh. A total of 765 samples, including cloacal swabs (535), visceral organs (50), and droppings (180), were collected from chickens of 12 layer flocks in 11 districts. Salmonella Gallinarum was isolated and characterized through culture-based method, followed by biochemical tests, sero-grouping, PCR assays, sequencing, and antibiogram. The identity of biochemically detected isolates of Salmonella Gallinarum was confirmed via genus-specific 16S rRNA gene based PCR, followed by invA and spvC genes based PCR assays. Occurrence of Salmonella Gallinarum was detected in overall 25.75% (197/765) samples, with a significantly (p < 0.05) higher incidence in visceral organs (42%) in comparison to cloacal swab (24%) and droppings (26%). Sequencing and subsequent phylogenetic analysis of invA and spvC genes in representative strains of Salmonella Gallinarum revealed a close genetic lineage, with a sequence similarity of 98.05-99.21% and 97.51-99.45%, respectively, to previously published sequences of the corresponding genes from the same serogroup strains. Remarkably, 66.5% (131/197) of the isolated strains of Salmonella Gallinarum were found to be resistant to 3 to 6 antimicrobial agents, and interpreted as multidrug resistant (MDR). The findings of this study underscore an inherent need of appropriate control measures to curb the widespread incidence of MDR Salmonella Gallinarum in small-scale commercial layer flocks, thereby, facilitating enhanced egg production and further support to the food security and safety in low resource settings.

Occurrence of Campylobacter spp. in Selected Small Scale Commercial Broiler Farms of Bangladesh Related to Good Farm Practices.

Poultry origin Campylobacter is considered as one of the leading causal agents of human foodborne illness. This study was conducted to estimate the occurrence, molecular identification, and antimicrobial resistance (AMR) of Campylobacter species from the broiler farms in Bangladesh. Samples (352) were collected from 32 farms and comprised of 128 cloacal swab, 64 feed, 64 drinking water, 64 attendants' hand rinsed water, and 32 whole carcasses. All samples were tested for the presence of Campylobacter via cultural, biochemical, and PCR. The AMR was determined via the disc diffusion method. An overall occurrence of Campylobacter spp. was estimated as 26.4%. The level of Campylobacter contamination was found to be higher in conventional farms (36.4%) than the good practice farms (16.5%) including all sample categories (p = 0.000). Of 93 isolates, 67.74% and 32.26% were confirmed as C. jejuni and C. coli respectively, of which 34.92% C. jejuni, and 30% C. coli were shown to be multidrug-resistant. A significant occurrence of Campylobacter contamination in broiler farms with multidrug resistant patterns might be cogitated as serious food safety and public health concern linking to poultry food chain. A risk reduction approach through good farming practices targeting the prudent use of antimicrobials for broiler production is thus necessitated.

Bovine tuberculosis prevalence and risk factors in selected districts of Bangladesh.

A cross-sectional survey was conducted in selected districts of Bangladesh to estimate the prevalence of bovine tuberculosis (bTB), and to identify the risk factors for bTB. We included 1865 farmed cattle from 79 herds randomly selected from five districts. Herd and animal level data were collected using semi-structured interviews with cattle herd owners. The single intradermal comparative tuberculin test (SICTT) was used to estimate the prevalence of bTB. The risk factors were identified using mixed-effect multiple logistic regression analyses. The overall herd and animal level prevalences of bTB were estimated to be 45.6% (95% Confidence Interval [CI] = 34.3-57.2%) and 11.3 (95% CI = 9.9-12.8%), respectively, using the OIE recommended >4 mm cut-off. The true animal level prevalence of bTB was estimated to be 11.8 (95% Credible Interval = 2.1-20.3%). At the herd level, farm size, bTB history of the farm and type of husbandry were significantly associated with bTB status in univariable analysis. Similarly, age group, sex, pregnancy status and parity were significantly associated with bTB at cattle level. However, in multivariable analysis only herd size at the herd level and age group and pregnancy status at the cattle level were significant. Compared to a herd size of 1-10, the odds of bTB were 22.8 (95% CI: 5.2-100.9) and 45.6 times (95% CI: 5.0-417.7) greater in herd sizes of >20-50 and >50, respectively. The odds of bTB were 2.2 (95% CI: 1.0-4.5) and 2.5 times (95% CI: 1.1-5.4) higher in cattle aged >3-6 years and > 6 years, compared to cattle aged ≤1 year. Pregnancy increased the odds of bTB by 1.7 times (95% CI: 1.2-2.4) compared to non-pregnant cattle. Taken together, the results suggest high herd and animal level prevalence of bTB in these 5 districts, with the greatest risk of bTB in older and pregnant cattle within large herds (>20), and highlight an urgent need for continued surveillance and implementation of bTB control programs in Bangladesh.

Foot-and-Mouth Disease Space-Time Clusters and Risk Factors in Cattle and Buffalo in Bangladesh.

Foot-and-mouth disease (FMD) is highly endemic in Bangladesh. Using passive surveillance data (case records from all 64 districts of Bangladesh, 2014-2017) and district domestic ruminant population estimates, we calculated FMD cumulative incidence per 10,000 animals at risk per district, conducted cluster (Moran's spatial autocorrelation and scan statistics) and hotspot analysis (local indicator of spatial association statistic), created predictive maps and identified risk factors using a geographically weighted regression model. A total of 548,817 FMD cases in cattle and buffalo were reported during the four-year study period. The highest proportion (31.5%) of cases were reported during the post-monsoon season, and from Chattogram (29.2%) division. Five space-time clusters, 9 local clusters, and 14 hotspots were identified. Overall, higher cumulative incidences of FMD were consistently predicted in eastern parts of Bangladesh. The precipitation in the pre-monsoon season (p = 0.0008) was positively associated with FMD in Bangladesh. Results suggest climate plays an important role in the epidemiology of FMD in Bangladesh, and high risk zones exist. In a resource limited-setting, hotspots and clusters should be prioritized for vaccination coverage, and surveillance for FMD should be targeted in eastern areas of Bangladesh and during the post-monsoon season.

Risk of multi-drug resistant Campylobacter spp. and residual antimicrobials at poultry farms and live bird markets in Bangladesh.

BACKGROUND: Understanding potential risks of multi-drug resistant (MDR) pathogens from the booming poultry sector is a crucial public health concern. Campylobacter spp. are among the most important zoonotic pathogens associated with MDR infections in poultry and human. This study systematically examined potential risks and associated socio-environmental factors of MDR Campylobacter spp. in poultry farms and live bird markets (LBMs) of Bangladesh. METHODS: Microbial culture and PCR-based methods were applied to examine the occurrence and MDR patterns of Campylobacter spp. in potential sources (n = 224) at 7 hatcheries, 9 broiler farms and 4 LBMs in three sub-districts. Antimicrobial residues in broiler meat and liver samples (n = 50) were detected by advanced chromatographic techniques. A questionnaire based cross-sectional survey was conducted on socio-environmental factors. RESULTS: Overall, 32% (71/ 224) samples were found contaminated with Campylobacter spp. In poultry farms, Campylobacter spp. was primarily found in cloacal swab (21/49, 43%), followed by drinking water (8/24, 33%), and meat (8/28, 29%) samples of broilers. Remarkably, at LBMs, Campylobacter spp. was detected in higher prevalence (p < 0.05) in broiler meat (14/26, 54%), which could be related (p < 0.01) to bacterial contamination of drinking water (11/21, 52%) and floor (9/21, 43%). Campylobacter isolates, one from each of 71 positive samples, were differentiated into Campylobacter jejuni (66%) and Campylobacter coli (34%). Alarmingly, 49 and 42% strains of C. jejuni and C. coli, respectively, were observed as MDR, i.e., resistant to three or more antimicrobials, including, tetracycline, amoxicillin, streptomycin, fluoroquinolones, and macrolides. Residual antimicrobials (oxytetracycline, ciprofloxacin and enrofloxacin) were detected in majority of broiler liver (79%) and meat (62%) samples, among which 33 and 19%, respectively, had concentration above acceptable limit. Inadequate personal and environmental hygiene, unscrupulously use of antimicrobials, improper waste disposal, and lack of health surveillance were distinguishable risk factors, with local diversity and compound influences on MDR pathogens. CONCLUSION: Potential contamination sources and anthropogenic factors associated with the alarming occurrence of MDR Campylobacter, noted in this study, would aid in developing interventions to minimize the increasing risks of poultry-associated MDR pathogens under 'One Health' banner that includes poultry, human and environment perspectives.

Fascioliasis risk factors and space-time clusters in domestic ruminants in Bangladesh.

BACKGROUND: A retrospective observational study was conducted to identify fascioliasis hotspots, clusters, potential risk factors and to map fascioliasis risk in domestic ruminants in Bangladesh. Cases of fascioliasis in cattle, buffalo, sheep and goats from all districts in Bangladesh between 2011 and 2013 were identified via secondary surveillance data from the Department of Livestock Services' Epidemiology Unit. From each case report, date of report, species affected and district data were extracted. The total number of domestic ruminants in each district was used to calculate fascioliasis cases per ten thousand animals at risk per district, and this was used for cluster and hotspot analysis. Clustering was assessed with Moran's spatial autocorrelation statistic, hotspots with the local indicator of spatial association (LISA) statistic and space-time clusters with the scan statistic (Poisson model). The association between district fascioliasis prevalence and climate (temperature, precipitation), elevation, land cover and water bodies was investigated using a spatial regression model. RESULTS: A total of 1,723,971 cases of fascioliasis were reported in the three-year study period in cattle (1,164,560), goats (424,314), buffalo (88,924) and sheep (46,173). A total of nine hotspots were identified; one of these persisted in each of the three years. Only two local clusters were found. Five space-time clusters located within 22 districts were also identified. Annual risk maps of fascioliasis cases correlated with the hotspots and clusters detected. Cultivated and managed (P < 0.001) and artificial surface (P = 0.04) land cover areas, and elevation (P = 0.003) were positively and negatively associated with fascioliasis in Bangladesh, respectively. CONCLUSIONS: Results indicate that due to land use characteristics some areas of Bangladesh are at greater risk of fascioliasis. The potential risk factors, hot spots and clusters identified in this study can be used to guide science-based treatment and control decisions for fascioliasis in Bangladesh and in other similar geo-climatic zones throughout the world.