Internationale Pferdebewegungen und Weiterverbreitung von Pferdeseuchen am Beispiel von Ansteckender Blutarmut der Einhufer und Rotz

International trade with horses is important and continuously increasing. Therefore the risk of spread of infectious diseases is permanently present. Within this context the worldwide situation of equine vector-borne diseases and of other diseases which are notifiable to the World Organisation of Animal Health (OIE), is described. Furthermore it provides estimates of the numbers of horse movements between these countries, as well as information on import requirements and preventive measures for reducing the risk of disease spread. According to TRACES (Trade Control and Expert System of the European Union) data from 2009 and 2010 81 horses per week were imported from North America into Europe, 42 horses per week from South America, 11 horses per week from the North of Africa and the African horse sichness free-zone of South Africa, 28 per week from the Middle East and the rest of Asia and approximately 4 horses per week from Australia / Oceania. Trade within the European Union resulted amongst others in the introduction of Equine Infectious Anaemia (EIA) from Roma- nia into other European countries. Another example is the suspected case of glanders which occurred after importation of horses from Leb- anon via France and Germany into Switzerland in July 2011.Der internationale Handel mit Pferden ist sehr bedeutend und stetig wachsend. Das Risiko einer Seuchenverbreitung ist somit permanent präsent. In diesem Zusammenhang wird die globale Situation Vektor-übertragener equiner Seuchen, sowie anderer der Welttiergesundheits-Organisation (OIE) meldepflichtiger Krankheiten dargestellt. Zudem werden Zahlen zu den weltweiten Pferdebewegungen, Informationen zu den Einfuhrbedingungen und Präventionsmassnahmen der Seucheneinschleppung beschrieben. Gemäß den Angaben von TRACES (Trade Control and Expert System der Europäischen Union) aus den Jahren 2009 und 2010 wurden 81 Pferde pro Woche aus Nordamerika, 42 Pferde pro Woche aus Südamerika, 11 Pferde pro Woche aus Nordafrika und der Pferdepest-freien Zone in Südafrika, 28 pro Woche aus dem mittleren Osten und aus dem übrigen Asien, sowie ca. 4 Pferde pro Woche aus Australien und Ozeanien nach Europa importiert. Mit dem Handel innerhalb der EU kam es unter anderem zur Einschleppung der Ansteckenden Blutarmut der Einhufer (Equine Infektiöse Anämie EIA) aus Rumänien in andere europäische Länder. Ein weiteres Beispiel ist der Rotzverdachtsfall, der nach Einfuhr von Pferden aus dem Libanon über Frankreich und Deutschland in die Schweiz im Juli 2011 auftrat

Epidemiological tracing of bovine tuberculosis in Switzerland, multilocus variable number of tandem repeat analysis of <i>Mycobacterium bovis</i> and <i>Mycobacterium caprae</i>

<div><p>Background</p><p>After 15 years of absence, in 2013 bovine tuberculosis (bTB), caused by <i>Mycobacterium</i> (<i>M</i>.) <i>bovis</i> and <i>M</i>. <i>caprae</i>, reemerged in the Swiss dairy cattle population. In order to identify the sources of infection as well as the spread of the agents, molecular-epidemiologic tracing by MIRU-VNTR analysis in combination with spoligotyping was performed. A total of 17 <i>M</i>. <i>bovis</i> and 7 <i>M</i>. <i>caprae</i> isolates were cultured from tuberculous bovine lymph nodes and analyzed with a set of 49 genetic markers by using automated capillary electrophoresis.</p><p>Results</p><p>The outbreak in the western part of Switzerland was caused by <i>M</i>. <i>bovis</i> spoligotype SB0120. With the exception of four single-locus variations observed in MIRU 20, the MIRU-VNTR profiles of the 17 <i>M</i>. <i>bovis</i> isolates were identical, indicating a single source of infection. <i>M</i>. <i>bovis</i> detected in one archival bovine specimen from the outbreak region showed an identical MIRU-VNTR profile, suggesting persistence of the agent in a dairy herd for nearly fifteen years. The outbreak in the eastern part of Switzerland was caused by <i>M</i>. <i>caprae</i> spoligotype SB0418. All Swiss <i>M</i>. <i>caprae</i> isolates showed the Lechtal-type MIRU-VNTR profile, described as endemic in wild ruminants and in dairy cattle in Austrian bordering regions. This suggests the agent was most likely introduced by Swiss dairy cattle summering on Austrian pastures.</p><p>Conclusions</p><p>The present study is the first MIRU-VNTR analysis of Swiss bTB mycobacterial isolates. The genotyping assay was found to be highly discriminating and suitable for the epidemiological tracing of further outbreaks. These findings will contribute to the development of an international MIRU-VNTR database aiming to improve bTB surveillance.</p></div

Evaluation of the benefit of emergency vaccination in a foot-and-mouth disease free country with low livestock density

Foot-and-mouth disease (FMD) is highly contagious and one of the most economically devastating diseases of cloven-hoofed animals. Scientific-based preparedness about how to best control the disease in a previously FMD-free country is therefore essential for veterinary services. The present study used a spatial, stochastic epidemic simulation model to compare the effectiveness of emergency vaccination with conventional (non-vaccination) control measures in Switzerland, a low-livestock density country. Model results revealed that emergency vaccination with a radius of 3 km or 10 km around infected premises (IP) did not significantly reduce either the cumulative herd incidence or epidemic duration if started in a small epidemic situation where the number of IPs is still low. However, in a situation where the epidemic has become extensive, both the cumulative herd incidence and epidemic duration are reduced significantly if vaccination were implemented with a radius of 10 km around IPs. The effect of different levels of conventional strategy measures was also explored for the non-vaccination strategy. It was found that a lower compliance level of farmers for movement restrictions and delayed culling of IPs significantly increased both the cumulative IP incidence and epidemic duration. Contingency management should therefore focus mainly on improving conventional strategies, by increasing disease awareness and communication with stakeholders and preparedness of culling teams in countries with a livestock structure similar to Switzerland; however, emergency vaccination should be considered if there are reasons to believe that the epidemic may become extensive, such as when disease detection has been delayed and many IPs are discovered at the beginning of the epidemic

Probable bTB transmission by which the infection spread between cattle of different farms in the outbreak caused by <i>M</i>. <i>bovis</i> SB0120.

<p>Arrows indicate movements of confirmed infected animals. Since cattle from two farms (only RT-PCR positive samples) spent the summer months on pasture together with animals originating from both farm A and farm B, unequivocal epidemiological contact tracing at single animal level was not demonstrable. These two premises are therefore not displayed.</p

Allele profiles of Swiss <i>M</i>. <i>bovis</i> and <i>M</i>. <i>caprae</i> isolates compared with three reference strains in the 24 MIRU-VNTR standard panel (A) and in the 25 MIRU-VNTR additional <i>loci</i> (B).

<p>Allele profiles of Swiss <i>M</i>. <i>bovis</i> and <i>M</i>. <i>caprae</i> isolates compared with three reference strains in the 24 MIRU-VNTR standard panel (A) and in the 25 MIRU-VNTR additional <i>loci</i> (B).</p

Allelic ladder specific for <i>locus</i> VNTR 3232 (A) and VNTR 2163a (B).

<p>The commercial size marker provided by the manufacturer was replaced with band ladders generated by different repeat numbers of <i>locus</i> VNTR 3232 (A) and VNTR 2163a (B). Allelic ladders represent a satisfactory solution for the problem of overestimation error due to the different nucleotide sequences between the size marker and analyzed fragment.</p

Map of Switzerland showing the geographical origin of the positive samples.

<p>Green stars indicate <i>M</i>. <i>caprae</i>, red stars <i>M</i>. <i>bovis</i>, both positive by RT-PCR testing and successively in culture; yellow stars indicate samples positive by direct RT-PCR though mycobacteria were not isolated in culture. Swiss Cantons where cases of bTB were detected are highlighted. The free software QGIS was used for map design (Source of layers: Swiss Federal Office of Topography).</p