A random effect meta-analysis was performed to estimate the worldwide pooled bovine viral diarrhoea virus (BVDV) prevalences of persistently infected (PI), viraemic (VI) and antibody-positive (AB) animals and herds. The meta-analysis covered 325 studies in 73 countries that determined the presence or absence of BVDV infections in cattle from 1961 to 2016. In total, 6.5 million animals and 310,548 herds were tested for BVDV infections in the global cattle population. The worldwide pooled PI prevalences at animal level ranged from low (≤0.8% Europe, North America, Australia), medium (>0.8% to 1.6% East Asia) to high (>1.6% West Asia). The PI and AB prevalences in Europe decreased over time, while BVDV prevalence increased in North America. The highest mean pooled PI prevalences at animal level were identified in countries that had failed to implement any BVDV control and/or eradication programmes (including vaccination). Our analysis emphasizes the need for more standardised epidemiological studies to support decision-makers implementing animal health policies for non-globally-regulated animal diseases.
In Deutschland sinkt die Zahl der Tuberkulose-Neuerkrankungen in den letzten Jahren weiterhin geringfügig. Erkrankungsfälle werden aufgrund der uncharakteristischen Klinik der Tuberkulose häufig spät diagnostiziert. Der Erfolg bei den Umgebungsuntersuchungen der Gesundheitsämter, Erkrankungsfälle innerhalb einer Infektkette zu finden, hängt u. a. von der Compliance der Erkrankten ab. Tuberkulose tritt insbesondere in Gruppen mit sozialer Benachteiligung auf. In dieser Bevölkerungsschicht gestalten sich die Ermittlungen von Kontaktpersonen eines an infektiöser Tuberkulose Erkrankten schwierig. Zudem gelingt es häufig nicht, die Infektionsquelle ausfindig zu machen. Aus diesen Gründen werden weitere Infektionen und Erkrankungen verursacht. Der kulturelle Erregernachweis, einschließlich Typendifferenzierung und Resistenztestung, ist nach wie vor der „Goldstandard“ in der Tuberkulosediagnostik und zur Untersuchung von Ausbrüchen erforderlich. Molekulare Methoden zur Feintypisierung isolierter Bakterienstämmen und deren anschließender Vergleich stellen ein wichtiges Hilfsmittel bei der infektionsepidemiologischen Aufklärung von Erkrankungshäufungen dar 1. Ziel dieser Arbeit ist die Darstellung einer Tuberkulose-Infektkette in Sachsen-Anhalt, die mithilfe einer molekularbiologischen Methode bewiesen wurde. Die konservative Methode stellt die Umgebungsuntersuchung zur zielführenden Auswahl der Kontaktpersonen dar. Die Ermittlungen laufen dabei immer in 2 Richtungen. Einerseits wird nach der noch unbekannten Infektionsquelle gesucht. Andererseits sollen Personen gefunden werden, die sich vor Bekanntwerden der Diagnose angesteckt haben. Die Diagnostik der Kontaktpersonen umfasst neben der Thoraxröntgenuntersuchung (TRU), den Tuberkulinhauttest nach Mendel-Mantoux (THT), Sputumuntersuchungen und den Einsatz des Interferon-Gamma (INF-γ) Tests (IGRA). Im beschriebenen Fall wurde als zusätzliches Instrument die molekularbiologische Methode des Spoligotypings gewählt. Dabei werden von den Tuberkulose-Stämmen der Patienten Fingerprint-Muster erstellt und miteinander verglichen. Aus den Umgebungsuntersuchungen hervorgehende Infektketten werden somit gesichert. Wir berichten über einen Tuberkulose-Ausbruch in einem Landkreis des Landes Sachsen-Anhalt, der sich im Zeitraum von Juni 2007 bis Mai 2010 ereignete. Als Ergebnis der Umgebungsuntersuchungen wurde eine Infektkette von 13 Erkrankten (77% ♂, 23% ♀) ermittelt. In 11 Fällen wurde durch Spoligotyping der Zusammenhang der Infektkette bewiesen (9 ♂, 2 ♀). 2 Fälle (1 ♂, 1 ♀), ohne Erregernachweis, lassen sich aufgrund der epidemiologischen Zusammenhänge zuordnen.
Abstract Background Blackleg and gas gangrene are acute clostridial infections primarily affecting cattle. The objectives of this study were to identify (i) animal‐related factors influencing the occurrence and (ii) prognostic pathological findings supporting the differentiation of fatal blackleg and gas gangrene cases in the cattle population from 1998 to 2018 in Styria, Austria. Methods Two binomial logistic models were applied to analyse the research questions. Additionally, cross‐validations were performed to estimate the accuracy of the predictive models. Results Model results show that animal‐related factors (i.e., age, geographical discovery location of dead cattle, vaccination status) significantly influence the occurrence of blackleg when compared to gas gangrene. Pathological findings are similar for both diseases. Conclusions Model results reveal that using animal‐related factors has a better accuracy to predict the fatal cases caused by both pathogens. Thus, the authors recommend not relying on pathological findings as predictive factors in the differentiation between blackleg and gas gangrene in cattle.
Bovine viral diarrhoea virus (BVDV) is an important infectious agent of cattle worldwide that affects herd productivity and reproduction. In this systematic review of the impact of BVDV, studies were analysed with a particular focus on the monetary implications and types of direct losses, the initial infection status of herds, production systems, time periods of assessment, calculation level, study types and whether or not country-specific assessments were published. A linear mixed model was applied to analyse factors that influence the level of monetary direct losses due to BVDV infection. The 44 studies included in this review covered 15 countries and assessed direct monetary losses due to BVDV incurred over the past 30 years. Direct losses between and within countries were largely heterogeneous with respect to the monetary level and types of direct losses, ranging from 0.50 to 687.80 US dollars (USD) per animal.1 Average direct losses per naïve dairy cow were USD24.85 higher than per beef cow. Country-specific assessments of direct losses due to BVDV were provided in 38/44 (86.4%) studies. Mortality, morbidity, premature culling, stillbirths, abortion, reinfection, country and study type had a significant influence on the monetary level of direct losses (r2 = 0.69). Countries recording direct losses were more likely to carry out voluntary or compulsory control and eradication programmes (odds ratio = 10.2; 95% confidence interval 1.7-81.9; P = 0.004).
Bluetongue virus (BTV) is an emerging transboundary disease in Europe, which can cause significant production losses among ruminants. The analysis presented here assessed the costs of BTV surveillance and vaccination programmes in Austria and Switzerland between 2007 and 2016. Costs were compared with respect to time, type of programme, geographical area and who was responsible for payment. The total costs of the BTV vaccination and surveillance programmes in Austria amounted to €23.6 million, whereas total costs in Switzerland were €18.3 million. Our analysis demonstrates that the costs differed between years and geographical areas, both within and between the two countries. Average surveillance costs per animal amounted to approximately €3.20 in Austria compared with €1.30 in Switzerland, whereas the average vaccination costs per animal were €6.20 in Austria and €7.40 in Switzerland. The comparability of the surveillance costs is somewhat limited, however, due to differences in each nation's surveillance (and sampling) strategy. Given the importance of the export market for cattle production, investments in such programmes are more justified for Austria than for Switzerland. The aim of the retrospective assessment presented here is to assist veterinary authorities in planning and implementing cost‐effective and efficient control strategies for emerging livestock diseases.
Infection with bovine viral diarrhea virus (BVDV) results in major economic losses either directly through decreased productive performance in cattle herds or indirectly, such as through expenses for control programs. The aim of this systematic review was to review financial and/or economic assessment studies of prevention and/or mitigation activities of BVDV at national, regional and farm level worldwide. Once all predefined criteria had been met, 35 articles were included for this systematic review. Studies were analyzed with particular focus on the type of financially and/or economically-assessed prevention and/or mitigation activities. Due to the wide range of possible prevention and/or mitigation activities, these activities were grouped into five categories: i) control and/or eradication programs, ii) monitoring or surveillance, iii) prevention, iv) vaccination and v) individual culling, control and testing strategies. Additionally, the studies were analyzed according to economically-related variables such as efficiency, costs or benefits of prevention and/or mitigation activities, the applied financial and/or economic and statistical methods, the payers of prevention and/or mitigation activities, the assessed production systems, and the countries for which such evaluations are available. Financial and/or economic assessments performed in Europe were dominated by those from the United Kingdom, which assessed mostly vaccination strategies, and Norway which primarily carried out assessments in the area of control and eradication programs; whereas among non-European countries the United States carried out the majority of financial and/or economic assessments in the area of individual culling, control and testing. More than half of all studies provided an efficiency calculation of prevention and/or mitigation activities and demonstrated whether the inherent costs of implemented activities were or were not justified. The dairy sector was three times more likely to be assessed by the countries than beef production systems. In addition, the dairy sector was approximately eight times more likely to be assessed economically with respect to prevention and/or mitigation activities than calf and youngstock production systems. Furthermore, the private sector was identified as the primary payer of prevention and/or mitigation activities. This systematic review demonstrated a lack of studies relating to efficiency calculations, in particular at national and regional level, and the specific production systems. Thus, we confirmed the need for more well-designed studies in animal health economics in order to demonstrate that the implementation and inherent costs of BVDV prevention and/or mitigation activities are justified.
This study evaluated the voluntary and compulsory implementation of a bovine viral diarrhoea virus (BVDV) eradication programme in the Austrian Federal State of Styria, Austria, from an economic point of view using ex-post assessment of costs and benefits (disease losses avoided). An economic net benefit (benefit:cost ratio, BCR = 1.18) of the programme was demonstrated during the voluntary programme phase (January 1998–July 2004). The break-even point was reached in 2003. If investments in the compulsory programme (August 2004–December 2016) were taken into account, a net economic loss (BCR = 0.16) was demonstrated. In contrast to on-going annual testing of all cattle herds, annual testing in accordance with a revised sampling scheme could reduce total surveillance costs by more than 77%. A Bayesian structural time series model was applied to analyse a hypothesised positive impact of the compulsory BVDV programme on the Styrian cattle export market. The average number of exported cows and bulls increased significantly by 42% (P = 0.03) and 47% (P = 0.01), respectively, and the producer price increased by 14% (P = 0.00) and 5% (P = 0.16), respectively, during the compulsory programme period compared with the period prior to intervention. This equates to an average revenue increase of €29,754 for cows and €137,563 for bulls per month. These results justify the implementation of eradication programmes, which initially may not appear to be economically viable, particularly if trade effects are not included in the calculations.
The aim of this study was to collect information on the global distribution of the prevalence of bovine viral diarrhoea virus (BVDV) and respective mitigation programmes, using a questionnaire and literature review to provide as complete a picture of the worldwide BVDV situation as possible. This study collated information on 107 countries with respect to mitigation activities and 88 countries regarding BVDV infections during the observation period (1960-2017). A heterogeneous epidemiological situation for both BVDV prevalence and the presence of mitigation programmes was observed. The results of this analysis could be used to increase the visibility of the distribution of BVDV, to provide supporting data for global animal disease databases and to assist veterinary public health authorities in the decision-making processes to establish mitigation activities.
