scholarly journals Bovine tuberculosis breakdown duration in cattle herds: an investigation of herd, host, pathogen and wildlife risk factors

Author(s):  
Georgina Milne ◽  
Adrian Allen ◽  
Jordon Graham ◽  
Angela Lahuerta-Marin ◽  
Carl McCormick ◽  
...  

Background. Despite rigorous controls placed on herds which disclose antemortem test positive cattle to bovine tuberculosis, caused by the infection of Mycobacterium bovis, many herds in Northern Ireland (NI) experience prolonged breakdowns. These herds represent a considerable administrative and financial burden to the State and farming community. Methods. A retrospective observational study was conducted to better understand the factors associated with breakdown duration, which was modelled using both negative binomial and ordinal regression approaches. Six explanatory variables were important predictors of breakdown length in both models; herd size, the number of reactors testing positive in the initial SICCT test, the presence of a lesioned animal at routine slaughter (LRS), the count of M. bovis genotypes during the breakdown (MLVA richness), the local herd-level bTB prevalence, and the presence of herds linked via management factors (associated herds). Results. We report that between 2008 and 2014, mean breakdown duration in NI was 226 days (approx. seven months; median; 188 days). In the same period, however, more than 6% of herds in the region remained under movement restriction for more than 420 days (13 months); almost twice as long as the mean. The MLVA richness variable was a particularly important predictor of breakdown duration. We contend that this variable primarily represents a proxy for beef fattening herds, which can operate by purchasing cattle and selling animals straight to slaughter, despite prolonged trading restrictions. For other herd types, the model supports the hypothesis that prolonged breakdowns are a function of both residual infection within the herd, and infection from the environment (e.g. infected wildlife, contiguous herds and/or a contaminated environment). The impact of badger density on breakdown duration was assessed by including data on main sett (burrow) density. Whilst a positive association was observed in the univariate analysis, confounding with other variables means that the contribution of badgers to prolonged breakdowns was not clear from our study. We do not fully reject the hypothesis that badgers are implicated in prolonging bTB breakdowns via spillback infection, but given our results, we posit that increased disease risk from badgers is unlikely to simply be a function of increasing badger density measured using sett metrics.

PeerJ ◽  
2020 ◽  
Vol 8 ◽  
pp. e8319 ◽  
Author(s):  
Georgina Milne ◽  
Adrian Allen ◽  
Jordon Graham ◽  
Angela Lahuerta-Marin ◽  
Carl McCormick ◽  
...  

Background Despite rigorous controls placed on herds which disclose ante-mortem test positive cattle to bovine tuberculosis, caused by the infection of Mycobacterium bovis, many herds in Northern Ireland (NI) experience prolonged breakdowns. These herds represent a considerable administrative and financial burden to the State and farming community. Methods A retrospective observational study was conducted to better understand the factors associated with breakdown duration, which was modelled using both negative binomial and ordinal regression approaches. Results Six explanatory variables were important predictors of breakdown length in both models; herd size, the number of reactors testing positive in the initial SICCT test, the presence of a lesioned animal at routine slaughter (LRS), the count of M. bovis genotypes during the breakdown (MLVA richness), the local herd-level bTB prevalence, and the presence of herds linked via management factors (associated herds). We report that between 2008 and 2014, mean breakdown duration in NI was 226 days (approx. seven months; median: 188 days). In the same period, however, more than 6% of herds in the region remained under movement restriction for more than 420 days (13 months); almost twice as long as the mean. The MLVA richness variable was a particularly important predictor of breakdown duration. We contend that this variable primarily represents a proxy for beef fattening herds, which can operate by purchasing cattle and selling animals straight to slaughter, despite prolonged trading restrictions. For other herd types, the model supports the hypothesis that prolonged breakdowns are a function of both residual infection within the herd, and infection from the environment (e.g. infected wildlife, contiguous herds and/or a contaminated environment). The impact of badger density on breakdown duration was assessed by including data on main sett (burrow) density. Whilst a positive association was observed in the univariate analysis, confounding with other variables means that the contribution of badgers to prolonged breakdowns was not clear from our study. We do not fully reject the hypothesis that badgers are implicated in prolonging bTB breakdowns via spillback infection, but given our results, we posit that increased disease risk from badgers is unlikely to simply be a function of increasing badger density measured using sett metrics.


2019 ◽  
Author(s):  
Georgina Milne ◽  
Adrian Allen ◽  
Jordon Graham ◽  
Angela Lahuerta-Marin ◽  
Carl McCormick ◽  
...  

Background. Despite rigorous controls placed on herds which disclose antemortem test positive cattle to bovine tuberculosis, caused by the infection of Mycobacterium bovis, many herds in Northern Ireland (NI) experience prolonged breakdowns. These herds represent a considerable administrative and financial burden to the State and farming community. Methods. A retrospective observational study was conducted to better understand the factors associated with breakdown duration, which was modelled using both negative binomial and ordinal regression approaches. Six explanatory variables were important predictors of breakdown length in both models; herd size, the number of reactors testing positive in the initial SICCT test, the presence of a lesioned animal at routine slaughter (LRS), the count of M. bovis genotypes during the breakdown (MLVA richness), the local herd-level bTB prevalence, and the presence of herds linked via management factors (associated herds). Results. We report that between 2008 and 2014, mean breakdown duration in NI was 226 days (approx. seven months; median; 188 days). In the same period, however, more than 6% of herds in the region remained under movement restriction for more than 420 days (13 months); almost twice as long as the mean. The MLVA richness variable was a particularly important predictor of breakdown duration. We contend that this variable primarily represents a proxy for beef fattening herds, which can operate by purchasing cattle and selling animals straight to slaughter, despite prolonged trading restrictions. For other herd types, the model supports the hypothesis that prolonged breakdowns are a function of both residual infection within the herd, and infection from the environment (e.g. infected wildlife, contiguous herds and/or a contaminated environment). The impact of badger density on breakdown duration was assessed by including data on main sett (burrow) density. Whilst a positive association was observed in the univariate analysis, confounding with other variables means that the contribution of badgers to prolonged breakdowns was not clear from our study. We do not fully reject the hypothesis that badgers are implicated in prolonging bTB breakdowns via spillback infection, but given our results, we posit that increased disease risk from badgers is unlikely to simply be a function of increasing badger density measured using sett metrics.


2021 ◽  
Vol 80 (Suppl 1) ◽  
pp. 900.1-900
Author(s):  
L. Diebold ◽  
T. Wirth ◽  
V. Pradel ◽  
N. Balandraud ◽  
E. Fockens ◽  
...  

Background:Among therapeutics used to treat rheumatoid arthritis (RA), Tocilizumab (TCZ) and Abatacept (ABA) are both biologic agents that can be delivered subcutaneously (SC) or intravenously (IV). During the first COVID-19 lockdown in France, all patients treated with IV TCZ or IV ABA were offered the option to switch to SC administration.Objectives:The primary aim was to assess the impact of changing the route of administration on the disease activity. The second aim was to assess whether the return to IV route at the patient’s request was associated with disease activity variation, flares, anxiety, depression and low physical activity during the lockdown.Methods:We conducted a prospective monocentric observational study. Eligibility criteria: Adult ≥ 18 years old, RA treated with IV TCZ or IV ABA with a stable dose ≥3 months, change in administration route (from IV to SC) between March 16, 2020, and April 17, 2020. The following data were collected at baseline and 6 months later (M6): demographics, RA characteristics, treatment, history of previous SC treatment, disease activity (DAS28), self-administered questionnaires on flares, RA life repercussions, physical activity, anxiety and depression (FLARE, RAID, Ricci &Gagnon, HAD).The primary outcome was the proportion of patients with a DAS28 variation>1.2 at M6. Analyses: Chi2-test for quantitative variables and Mann-Whitney test for qualitative variables. Factors associated with return to IV route identification was performed with univariate and multivariate analysis.Results:Among the 84 patients who were offered to switch their treatment route of administration, 13 refused to change their treatment. Among the 71 who switched (48 TCZ, 23 ABA), 58 had a M6 follow-up visit (13 lost of follow-up) and DAS28 was available for 49 patients at M6. Main baseline characteristics: female 81%, mean age 62.7, mean disease duration: 16.0, ACPA positive: 72.4%, mean DAS28: 2.01, previously treated with SC TCZ or ABA: 17%.At M6, the mean DAS28 variation was 0.18 ± 0.15. Ten (12.2%) patients had a DAS28 worsening>1.2 (ABA: 5/17 [29.4%] and TCZ: 5/32 [15.6%], p= 0.152) and 19 patients (32.8%) had a DAS28 worsening>0.6 (ABA: 11/17 [64.7%] and TCZ: 8/32 [25.0%], p= 0.007).At M6, 41 patients (77.4%) were back to IV route (26 TCZ, 15 ABA) at their request. The proportion of patients with a DAS28 worsening>1.2 and>0.6 in the groups return to IV versus SC maintenance were 22.5%, 42.5% versus 11.1% and 22.2% (p=0.4), respectively. The univariate analysis identified the following factors associated with the return to IV route: HAD depression score (12 vs 41, p=0.009), HAS anxiety score (12 vs 41, p=0.047) and corticosteroid use (70% vs 100%, p=0.021), in the SC maintenance vs return to IV, respectively.Conclusion:The change of administration route of TCZ and ABA during the first COVID-19 lockdown was infrequently associated with a worsening of RA disease. However, the great majority of the patients (77.4%) request to return to IV route, even without disease activity worsening. This nocebo effect was associated with higher anxiety and depression scores.Disclosure of Interests:None declared


2020 ◽  
Vol 7 (4) ◽  
pp. 191806
Author(s):  
Helen R. Fielding ◽  
Trevelyan J. McKinley ◽  
Richard J. Delahay ◽  
Matthew J. Silk ◽  
Robbie A. McDonald

Trading animals between farms and via markets can provide a conduit for spread of infections. By studying trading networks, we might better understand the dynamics of livestock diseases. We constructed ingoing contact chains of cattle farms in Great Britain that were linked by trading, to elucidate potential pathways for the transmission of infection and to evaluate their effect on the risk of a farm experiencing a bovine tuberculosis (bTB) incident. Our findings are consistent with variation in bTB risk associated with region, herd size, disease risk area and history of previous bTB incidents on the root farm and nearby farms. However, we also identified effects of both direct and indirect trading patterns, such that connections to more farms in the England High-Risk Area up to three movements away from the root farm increased the odds of a bTB incident, while connections with more farms in the England Low-Risk Area up to eight movements away decreased the odds. Relative to other risk factors for bTB, trading behaviours are arguably more amenable to change, and consideration of risks associated with indirect trading, as well direct trading, might therefore offer an additional approach to bTB control in Great Britain.


2019 ◽  
Vol 12 (1) ◽  
Author(s):  
James E. Truscott ◽  
Alison K. Ower ◽  
Marleen Werkman ◽  
Katherine Halliday ◽  
William E. Oswald ◽  
...  

Abstract Background As many countries with endemic soil-transmitted helminth (STH) burdens achieve high coverage levels of mass drug administration (MDA) to treat school-aged and pre-school-aged children, understanding the detailed effects of MDA on the epidemiology of STH infections is desirable in formulating future policies for morbidity and/or transmission control. Prevalence and mean intensity of infection are characterized by heterogeneity across a region, leading to uncertainty in the impact of MDA strategies. In this paper, we analyze this heterogeneity in terms of factors that govern the transmission dynamics of the parasite in the host population. Results Using data from the TUMIKIA study in Kenya (cluster STH prevalence range at baseline: 0–63%), we estimated these parameters and their variability across 120 population clusters in the study region, using a simple parasite transmission model and Gibbs-sampling Monte Carlo Markov chain techniques. We observed great heterogeneity in R0 values, with estimates ranging from 1.23 to 3.27, while k-values (which vary inversely with the degree of parasite aggregation within the human host population) range from 0.007 to 0.29 in a positive association with increasing prevalence. The main finding of this study is the increasing trend for greater parasite aggregation as prevalence declines to low levels, reflected in the low values of the negative binomial parameter k in clusters with low hookworm prevalence. Localized climatic and socioeconomic factors are investigated as potential drivers of these observed epidemiological patterns. Conclusions Our results show that lower prevalence is associated with higher degrees of aggregation and hence prevalence alone is not a good indicator of transmission intensity. As a consequence, approaches to MDA and monitoring and evaluation of community infection status may need to be adapted as transmission elimination is aimed for by targeted treatment approaches.


Blood ◽  
2012 ◽  
Vol 120 (21) ◽  
pp. 4483-4483
Author(s):  
Amandine Lebourgeois ◽  
Marion Loirat ◽  
Benoit Tessoulin ◽  
Elsa Lestang ◽  
Pierre Peterlin ◽  
...  

Abstract Abstract 4483 Introduction: RIC regimens are increasingly used prior to allo-SCT. The FB2 regimen (Fludarabine 120–150 mg/m2 + IV Busulfan 6.4 mg/Kg + ATG Thymoglobuline 5mg/Kg) is currently the most widely used RIC regimen in many European centres. This retrospective analysis aimed to assess the hematopoietic and immune recovery in a homogeneously treated cohort of 53 patients (males: n=33; median age: 59 years (range: 22–70)) who received the FB2 regimen between January 2007 and October 2010 in our department. Patients and Methods: Diagnoses were as follow: AML n=23; ALL n=1; biphenotypic leukemia n=1; lymphoma n=16; myelodysplastic syndrome n=9; multiple myeloma n=3. Nineteen patients (36%) had received a prior autologous SCT. The majority of patients (n=40, 75.5%) were transplanted in complete remission. Thirty patients received a graft from a matched sibling donor (56.5%). All patients, but one (who received unmanipulated bone marrow) received G-CSF-mobilized PBSCs. GVHD prophylaxis consisted of cyclosporine (CsA) alone in patients transplanted with an HLA-identical sibling, and CsA+ mycophenolate mofetyl in other cases. None of the patients received G-CSF during aplasia following transplant while nine patients received erythropoietin before day+100. Results: Engraftment was achieved in 96% of patients (n=51). Median times for neutrophils (n=51) and platelets (n=22) recovery were 17 days (range: 0–39) and 10 days (range: 4–186), respectively. The majority of patients (n=31, 58%) did not receive platelet support during aplasia. The cumulative incidences of grade II-IV and grade III-IV acute GVHD were 30% and 15%, respectively, while overall incidence of chronic extensive GVHD was 33%. With a median follow-up of 19 months (range: 2–53), the 2-year OS, DFS, relapse incidence, and NRM were 63%, 59.5%, 35% and 6%, respectively. In univariate analysis, when regarding pre-transplant factors associated with outcome, the only factor correlated with a significantly higher 2-year OS and DFS was a higher total circulating lymphocytes count at transplant (> 730/mm3) (OS: 81.5% vs 43.2%, p=0.01; DFS: 73.2% vs 45.5%, p=0.03). Regarding post-transplant factors, we found that higher recovery of leukocytes (>5000/mm3) (2-year OS: 78% vs 46%, p=0.007; 2-year DFS: 70% vs 48%, p=0.08), neutrophils (>3230/mm3) (2-year OS: 76% vs 50%, p=0.02; 2-year DFS: 67.5% vs 52.0%, p=0.09), and monocytes (>590/mm3) (2-year OS: 80% vs 47%, p=0.004; 2-year DFS: 75% vs 42%, p=0.007) at day+30 post-transplant were the most significant factors associated with outcome. In multivariate analysis, the only independent factors associated with a significantly higher OS and DFS were a better immune status at transplant (lymphocytes count >730/mm3; HR 0.22; 95%CI: 0.08–0.63, p=0.005; and HR: 0.29; 95%CI: 0.12–0.71, p=0.006, respectively) and a higher monocytes count at day+30 post-transplant (>590/mm3) (HR: 0.24; 95%CI: 0.08–0.66, p=0.006; and HR: 0.28; 95%CI: 0.11– 0.68, p=0.005; respectively). Conclusion: These results suggest that hematopoietic status and recovery before and after FB2 RIC allo-SCT can be significant predictors of outcome. This paves the way for future studies aiming to closely monitor the kinetics of immune recovery after RIC allo-SCT and to evaluate the impact of growth factors and other immunostimulatory cytokines in the setting of RIC allo-SCT. Disclosures: No relevant conflicts of interest to declare.


PLoS ONE ◽  
2021 ◽  
Vol 16 (1) ◽  
pp. e0222898
Author(s):  
Sylvain Coly ◽  
Myriam Garrido ◽  
David Abrial ◽  
Anne-Françoise Yao

Disease mapping aims to determine the underlying disease risk from scattered epidemiological data and to represent it on a smoothed colored map. This methodology is based on Bayesian inference and is classically dedicated to non-infectious diseases whose incidence is low and whose cases distribution is spatially (and eventually temporally) structured. Over the last decades, disease mapping has received many major improvements to extend its scope of application: integrating the temporal dimension, dealing with missing data, taking into account various a prioris (environmental and population covariates, assumptions concerning the repartition and the evolution of the risk), dealing with overdispersion, etc. We aim to adapt this approach to model rare infectious diseases proposing specific and generic variants of this methodology. In the context of a contagious disease, the outcome of a primary case can in addition generate secondary occurrences of the pathology in a close spatial and temporal neighborhood; this can result in local overdispersion and in higher spatial and temporal dependencies due to direct and/or indirect transmission. In consequence, we test models including a Negative Binomial distribution (instead of the usual Poisson distribution) to deal with local overdispersion. We also use a specific spatio-temporal link in order to better model the stronger spatial and temporal dependencies due to the transmission of the disease. We have proposed and tested 60 Bayesian hierarchical models on 400 simulated datasets and bovine tuberculosis real data. This analysis shows the relevance of the CAR (Conditional AutoRegressive) processes to deal with the structure of the risk. We can also conclude that the negative binomial models outperform the Poisson models with a Gaussian noise to handle overdispersion. In addition our study provided relevant maps which are congruent with the real risk (simulated data) and with the knowledge concerning bovine tuberculosis (real data).


Rheumatology ◽  
2019 ◽  
Vol 59 (2) ◽  
pp. 277-280 ◽  
Author(s):  
Winnie M Y Chen ◽  
Marwan Bukhari ◽  
Francesca Cockshull ◽  
James Galloway

Abstract Objective Scientific journals and authors are frequently judged on ‘impact’. Commonly used traditional metrics are the Impact Factor and H-index. However, both take several years to formulate and have many limitations. Recently, Altmetric—a metric that measures impact in a non-traditional way—has gained popularity. This project aims to describe the relationships between subject matter, citations, downloads and Altmetric within rheumatology. Methods Data from publications in Rheumatology were used. Articles published from 2010 to 2015 were reviewed. Data were analysed using Stata 14.2 (StataCorp, College Station, TX, USA). Correlation between citations, downloads and Altmetric were quantified using linear regression, comparing across disease topics. Relationship between downloads and months since publications were described using negative binomial regression, clustering on individual articles. Results A total of 1460 Basic Science and Clinical Science articles were identified, with the number of citations, downloads and Altmetric scores. There were no correlations between disease topic and downloads (R2 = 0.016, P = 0.03), citations (R2 = 0.011, P = 0.29) or Altmetric (R2 = 0.025, P = 0.02). A statistically significant positive association was seen between the number of citations and downloads (R2 = 0.29, P < 0.001). No correlations were seen between Altmetric and downloads (R2 = 0.028, P < 0.001) or citations (R2 = 0.004, P = 0.445). Conclusion Disease area did not correlate with any of the metrics compared. Correlations were apparent with clear links between downloads and citations. Altmetric identified different articles as high impact compared with citation or download metrics. In conclusion: tweeting about your research does not appear to influence citations.


2020 ◽  
Vol 41 (S1) ◽  
pp. s374-s375
Author(s):  
Mohammed Alsuhaibani ◽  
Alanoud Aljarboua ◽  
Sahar Althawadi ◽  
Abdurahman Alsweed ◽  
Sami Al-Hajjar

Background:Stenotrophomonas maltophilia (S. maltophilia) is an opportunistic and nosocomial pathogen that can cause an invasive and fatal infection, particularly in hospitalized and immunocompromised patients. However, little is known about the impact of S. maltophilia bacteremia in pediatric patients. Therefore, we aimed to identify risk factors for mortality, antibiotic susceptibility of S. maltophilia, and mortality rates in pediatric patients with S. maltophilia bacteremia. Methods: We conducted a retrospective cohort study by identifying all S. maltophilia–positive blood cultures in the microbiology laboratory database between January 2007 and December 2018 from hospitalized pediatric patients (age, 1–14 years) at King Faisal Specialist Hospital and Research Center, Riyadh, Saudi Arabia. After identifying patients with S. maltophilia bacteremia, medical charts were reviewed for demographics, clinical data, and outcome within 7 days of bacteremia diagnosis. Risk factors associated with mortality in S. maltophilia bacteremia patients were determined using univariate and multivariate analyses. Results: Overall, 68% of pediatric patients with S. maltophilia bacteremia were identified. The most common underlying primary diagnoses were malignancy (29.4%), congenital heart diseases (16.2%), anemia (14.7%), and primary immunodeficiency (11.8%). All infections were nosocomial infections, and (88.2%) bacteremia cases were central-line–associated bloodstream infections. The risk factors associated with mortality as determined by univariate analysis were ICU admission (P < .001), intubation (P = .001), neutropenia (P = .008), prior use of carbapenem (P = .002), thrombocytopenia (P = .006), and respiratory colonization (P < .001). On multivariate analysis, ICU admission (P = .007; 95% CI, 0.003–0.406) and neutropenia (P = .009; 95% CI, 0.013–0.537) were the major risk factors associated with mortality. S. maltophilia was the most susceptible to trimethoprim and sulfamethoxazole (TMP/SMX, 94.1%), followed by levofloxacin (85.7%). In addition, 36 patients received TMP/SMX as monotherapy, and 11 patients received it in combination with other antibiotics (fluoroquinolone, ceftazidime, or aminoglycoside). Hence, no statistically significant difference was observed in patient mortality. The overall mortality rate within 7 days of S. maltophilia bacteremia diagnosis was 33.8%. Conclusions:S. maltophilia bacteremia is a devastating emerging infection associated with high mortality among hospitalized children. Therefore, early diagnosis and prompt management based on local susceptibility data are crucial. Various risk factors, especially ICU admission and neutropenia, are associated with S. maltophilia bacteremia mortality.Funding: NoneDisclosures: None


Author(s):  
Adil Al Wahaibi ◽  
Amal Al Maani ◽  
Fatma Alyaquobi ◽  
Abdullah Al Manji ◽  
Khalid Al Harthy ◽  
...  

Background: Non-pharmaceutical interventions (NPIs), particularly mobility restrictions, are mainstay measures for the COVID-19 pandemic worldwide. We evaluated the effects of Oman’s mobility restriction strategies to highlight their efficacy in controlling the pandemic. Methods: Accessible national data of daily admissions and deaths were collected from 1 April 2020 to 22 May 2021. Google Community Mobility Report (CMR) data were downloaded for the same period. Among six CMR categories, three were used and reduced to one index—the community mobility index (CMI). We used a generalised linear model with a negative binomial distribution combined with a non-linear distributed lag model to investigate the short-term effects of CMI on the number of admitted PCR-confirmed COVID-19 cases and deaths, controlling for public holidays, day of the week, and Eid/Ramadan days. Results: We demonstrated the feasibility of using CMRs in the evaluation and monitoring of different NPIs, particularly those related to movement restriction. The best movement restriction strategy was a curfew from 7 p.m. to 5 a.m. (level 3 of CMI = 8), which had a total reduction of 35% (95% confidence interval (CI); 25–44%) in new COVID-19 admissions in the following two weeks, and a fatality reduction in the following four weeks by 52% (95% CI; 11–75%). Conclusion: Evening lockdown significantly affected the course of the pandemic in Oman which lines up with similar studies throughout the world.


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