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Vector-borne animal diseases pose a continuous and substantial threat to livestock economies around the globe. Increasing international travel, the globalisation of trade, and climate change are likely to play a progressively more important role in the introduction, establishment and spread of arthropod-borne pathogens worldwide. A review of the literature reveals that many climatic variables, functioning singly or in combination, exert varying effects on the distribution and range of Culicoides vector midges and mosquitoes. For example, higher temperatures may be associated with increased insect abundance--thereby amplifying the risk of disease transmission--but there are no indications yet of dramatic shifts occurring in the geographic range of Culicoides midges. However, the same cannot be said for mosquitoes: over the last few decades, multiple Asian species have established themselves in Europe, spread and are unlikely to ever be eradicated. Research on how insects respond to changes in climate is still in its infancy. The authors argue that we need to grasp how other annectant changes, such as extremes in precipitation (drought and flooding), may affect the dispersal capability of mosquitoes. Models are useful for assessing the interplay between mosquito vectors expanding their range and the native flora and fauna; however, ecological studies employing classical mark-release-recapture techniques remain essential for addressing fundamental questions about the survival and dispersal of mosquito species, with the resulting parameters fed directly into new-generation disease transmission models. Studies on the eventual impact of mosquitoes on animal and human health should be tackled through large-scale integrated research programmes. Such an approach calls for more collaborative efforts, along the lines of the One Health Initiative.

The aim of this study was to identify difficulties and barriers to reporting clinically suspect situations, possibly caused by avian influenza (AI), and to explore possible incentives to reporting such situations, with the ultimate aim of facilitating early detection of AI outbreaks. Focus group sessions were held with policy-makers from the competent authority, representatives of veterinary practitioners and poultry farmers. Personal interviews with a group of poultry farmers and practitioners were held to ascertain the difficulties and barriers they perceived and their proposed solutions. An electronic questionnaire was put on the websites of a poultry farmer union and the Royal Dutch Veterinary Association to investigate perceptions and attitudes concerning AI-suspect situations in The Netherlands. Six themes emerged identifying factors that hinder the reporting of a clinically suspect situation: lack of knowledge and uncertainty about clinical signs of AI; guilt, shame and prejudice; negative opinion of control measures; dissatisfaction with post-reporting procedures; lack of trust in veterinary authorities; lack of transparency in reporting procedures and uncertainty about the notification process. Recommendations to facilitate early detection of AI are discussed.

Any outbreak of an animal disease classified as a List A disease by the Office International des Epizooties, such as classical swine fever (CSF), has severe consequences for animal welfare, livestock production, exports of animals and animal products and the environment. Experience shows that early detection and response to a suspected disease outbreak will maximise the effectiveness of the emergency response actions and minimise the social, economic and environmental costs associated with the outbreak. The development and implementation of measures designed to minimise the risk of diseases entering a country or region has been the predominant animal health management strategy in most countries. However, even the strongest preventive management systems do not guarantee that outbreaks of animal diseases will not occur. Tracing, a procedure that begins with a known infected individual, herd or flock, and which traces all possible locational and interactive exposures in both directions, back towards the source and forward to contacts, is the backbone of disease emergency management. The authors provide an introduction to, and general overview of, tracking and tracing systems used during a recent epidemic of CSF in the Netherlands from 1997 to 1998.

From 1996 to 1999, blood samples were collected from wild boar shot during the hunting season in Crown properties, national parks and the free wildlife belt in the Netherlands. Sera were screened for the presence of antibodies against classical swine fever virus (CSFV), swine vesicular disease virus (SVDV), Aujeszky's disease virus (ADV) and Trichinella spiralis. The results of the sero-surveillance system indicate that CSFV, SVDV and ADV are uncommon within the wild boar population. Hence, the wild boar population is not thought to be an important reservoir of these viruses in the Netherlands. Infection with ADV and CSFV is endemic in the wild boar population in Germany. Since contact between the wild boar populations of Germany and the Netherlands cannot be excluded in the southern part of the Netherlands, continuation of the sero-surveillance system seems appropriate. In the decade before 1998, no antibodies to Trichinella spp. were found in the wild boar population of the Netherlands. The detection of some seropositive animals during the hunting season of 1998-1999 corresponds to the previous findings in wild boar before 1988. However, the recent data do not have consequences for the pig industry of the Netherlands, since the country has been considered Trichinella-free for many decades.

The authors describe the value of routine serological surveillance in detecting the introduction of classical swine fever virus into a disease-free population. The first investigation concerned the question of whether the epidemic of classical swine fever (CSF), which occurred from 1997 to 1998 in the Netherlands, could have been detected using the existing monitoring system for notifiable diseases. The investigation used data from the CSF epidemic of 1997/1998 and from the existing monitoring system. Secondly, the probability of detecting a case of CSF using routine serological surveillance was modelled both for multiplier herds and for finishing herds, and then for different herd size categories. The first investigation concluded that the probability of detecting the epidemic at the current level of routine serological surveillance is very low. The second investigation concluded that even employing a sampling scheme of sixty blood samples per month, the probability of detecting an outbreak of CSF within forty days of the introduction of the virus, is less than 40%.