ABSTRACT
Bluetongue (BT) disease poses a constant risk to the livestock population around the world. A better understanding of the risk factors will enable a more accurate prediction of the place and time of high-risk events. Mapping the disease epizootics over a period in a particular geographic area will identify the spatial distribution of disease occurrence. A Geographical Information System (GIS) based methodology to analyze the relationship between bluetongue epizootics and spatial-temporal patterns was used for the years 2000 to 2015 in sheep of Andhra Pradesh, India. Autocorrelation (ACF), partial autocorrelation (PACF), and cross-correlation (CCF) analyses were carried out to find the self-dependency between BT epizootics and their dependencies on environmental factors and livestock population. The association with climatic or remote sensing variables at different months lag, including wind speed, temperature, rainfall, relative humidity, normalized difference vegetation index (NDVI), normalized difference water index (NDWI), land surface temperature (LST), was also examined. The ACF & PACF of BT epizootics with its lag showed a significant positive autocorrelation with a month's lag (r = 0.41). Cross-correlations between the environmental variables and BT epizootics indicated the significant positive correlations at 0, 1, and 2 month's lag of rainfall, relative humidity, normalized difference water index (NDWI), and normalized difference vegetation index (NDVI). Spatial autocorrelation analysis estimated the univariate global Moran's I value of 0.21. Meanwhile, the local Moran's I value for the year 2000 (r = 0.32) showed a high degree of spatial autocorrelation. The spatial autocorrelation analysis revealed that the BT epizootics in sheep are having considerable spatial association among the outbreaks in nearby districts, and have to be taken care of while making any forecasting or disease prediction with other risk factors.
Subject(s)
Bluetongue , Sheep Diseases , Animals , Bluetongue/epidemiology , Disease Outbreaks/veterinary , India/epidemiology , Livestock , Sheep , WaterABSTRACT
This study describes the spatial and temporal patterns of bluetongue (BT) outbreaks with environmental factors in undivided Andhra Pradesh, India. Descriptive analysis of the reported BT outbreaks (n = 2,697) in the study period (2000-2017) revealed a higher frequency of outbreaks during monsoon and post-monsoon months. Correlation analysis of Normalized Difference Vegetation Index (NDVI), Normalized Difference Water Index (NDWI), rainfall and relative humidity (RH) displayed a significant positive correlation with BT outbreaks (p < .05). Retrospective unadjusted space-time, adjusted temporal and spatial analysis detected two, five and two statistically significant (p < .05) clusters, respectively. Time series distribution lag analysis examined the temporal patterns of BT outbreaks with environmental, biophysical factors and estimated that a decrease in 1 unit of rainfall (mm) was associated with 0.2% increase in the outbreak at lag 12 months. Similarly, a 1°C increase in land surface temperature (LST) was associated with 6.54% increase in the outbreaks at lag 12 months. However, an increase in 1 unit of wind speed (m/s) was associated with a 16% decrease in the outbreak at lag 10 months. The predictive model indicated that the peak of BT outbreaks were from October to December, the post-monsoon season in Andhra Pradesh region. The findings suggest that environmental factors influence BT outbreaks, and due to changes in climatic conditions, we may notice higher numbers of BT outbreaks in the coming years. The knowledge of spatial and temporal clustering of BT outbreaks may assist in adopting proper measures to prevent and control the BT spread.
Subject(s)
Bluetongue , Sheep Diseases , Animals , Bluetongue/epidemiology , Disease Outbreaks/veterinary , India/epidemiology , Retrospective Studies , Search Engine , SheepABSTRACT
A cross-sectional study on five organized pig farms was conducted to assess the faecal carriage of ESBL and blaNDM carbapenemase-producing E. coli in piglets and pig farmworkers. Faecal samples from piglets (n = 155) and pig farmworkers (n = 21) were processed for isolation and characterization of E. coli. A total of 124 E. coli isolates from piglets and 21 E. coli isolates pig farmworkers were recovered and screening for ESBL production showed that 44.4 % (55/124) of the isolates from piglets and 42.9 % (9/21) of the isolates from farmworkers were ESBL positive. The ESBL positive isolates from piglets and farmworkers harbored blaCTX-M and also co-harbored other beta-lactams, sulphonamide, quinolone and tetracycline resistance genes. Diarrhoeic (50%, 49/98) and crossbred piglets (52.7%, 39/74) harbored a significantly higher number of ESBL producing isolates than non-diarrhoeic (23.1 %, 6/26) and purebred piglets (32%, 16/50) (p < 0.05). Piglets and pig farmworkers harbored nine and two carbapenem-resistant isolates, respectively. Interestingly, two isolates from piglets and one isolate from farmworkers harbored the blaNDM gene. The blaNDM positive E. coli isolated from piglets and farmworkers of the same farm revealed similar antibacterial resistance patterns, resistant genes, sequence (ST-167) and plasmid type (IncX3). In India, carbapenems are not used in food animal treatment, hence carbapenem resistant E. coli in piglets possibly originated from the human contact or common environment and is of public health importance.
Subject(s)
Agricultural Workers' Diseases/microbiology , Escherichia coli Infections/veterinary , Escherichia coli/enzymology , Feces/microbiology , Swine Diseases/transmission , beta-Lactamases/metabolism , Agricultural Workers' Diseases/drug therapy , Agricultural Workers' Diseases/epidemiology , Animals , Anti-Bacterial Agents/pharmacology , Cross-Sectional Studies , Escherichia coli/classification , Escherichia coli/genetics , Escherichia coli Infections/drug therapy , Escherichia coli Infections/epidemiology , Escherichia coli Infections/transmission , Farmers , Feces/enzymology , Female , Humans , India/epidemiology , Male , Microbial Sensitivity Tests/veterinary , Swine , Swine Diseases/epidemiology , Swine Diseases/microbiology , Zoonoses/microbiology , Zoonoses/transmission , beta-Lactamases/geneticsABSTRACT
Bluetongue (BT) is an infectious viral disease which affects a wide range of ruminants and was first reported in India in 1964. In view of the absence of comprehensive information on the BT status in India, this study presents the seroprevalence on BT in farm animals of India based-on a systematic review and meta-analysis. A systematic review was conducted to identify the published articles (2001-2018) reporting the seroprevalence of BT in sheep, goats, cattle, buffalo, camels, and Mithun (Bos frontalis) from India. From 409 research articles, 71 fulfilled the inclusion criteria and meta-analysis for proportions was carried out targeting the eligible studies. From these, 144 strata level data were extracted with a sample size of 14048 sheep, 14696 goats, 5218 cattle, 2653 buffaloes, 2062 camels, and 222 Mithun. Overall, the analyses showed that the BT seroprevalence of 43% (95% CI: 38-49%) in goats, 39% (95% CI: 33-46%) in sheep, 38% (95% CI: 25-45%) in cattle, 34% (95% CI: 20-51%) in buffaloes, 16% (95% CI: 10-22%) in camels, and 66% (95% CI: 17-95%) in Mithun. Furthermore, the meta-regression analysis suggested that serological tests, geographical region, and sample size were the prime moderators. Meta-analytic study indicates the BT seropositivity in 25.35 million sheep (95% CI: 21.5-29.9), 58 million goats (95% CI: 51.3-66.2), 66.8 million cattle (95% CI: 47.7-86), 37.0 million buffaloes (95% CI: 21.7-55.4), 0.06 million camels (95% CI: 0.04-0.09), and 0.19 million Mithun (95% CI: 0.05-0.28). The findings highlight the variation of BT seropositivity in different geographical regions of India.
Subject(s)
Bluetongue/epidemiology , Ruminants/virology , Animals , Bluetongue/blood , Bluetongue/diagnosis , India/epidemiology , Livestock/virology , Risk Factors , Seroepidemiologic Studies , Sheep , Sheep Diseases/epidemiology , Sheep Diseases/virologyABSTRACT
A cross-sectional study was conducted from 2014 to 2017 in 13 organised pig farms located in eight states of India (Northern, North-Eastern and Southern regions) to identify the risk factors, pathotype and antimicrobial resistance of Escherichia coli associated with pre- and post-weaning piglet diarrhoea. The data collected through questionnaire survey were used to identify the risk factors by univariable analysis, in which weaning status, season, altitude, ventilation in the shed, use of heater/cooler for temperature control in the sheds, feed type, water source, and use of disinfectant, were the potential risk factors. In logistic regression model, weaning and source of water were the significant risk factors. The piglet diarrhoea prevalence was almost similar across the regions. Of the 909 faecal samples collected (North - 310, North-East - 194 and South - 405) for isolation of E. coli, pathotyping and antibiotic screening, 531 E. coli were isolated in MacConkey agar added with cefotaxime, where 345 isolates were extended spectrum ß-lactamase (ESBL) producers and were positive for blaCTX-M-1 (n = 147), bla TEM (n = 151), qnrA (n = 98), qnrB (n = 116), qnrS (n = 53), tetA (n = 46), tetB (n = 48) and sul1 (n = 54) genes. Multiple antibiotic resistance (MAR) index revealed that 14 (2.64%) isolates had MAR index of 1. On the virulence screening of E. coli, 174 isolates harboured alone or combination of Stx1, Stx2, eaeA, hlyA genes. The isolates from diarrhoeic and post-weaning samples harboured higher number of virulence genes than non-diarrhoeic and pre-weaning. Alleviating the risk factors might reduce the piglet diarrhoea cases. The presence of multidrug-resistant and ESBL-producing pathogenic E. coli in piglets appears a public health concern.