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Contagious bovine pleuropneumonia (CBPP), caused by Mycoplasma mycoides var. mycoides small colony (MmmSC), is one of the most important diseases of cattle in Africa. The role of innate or acquired cell mediated and humoral immunity in conferring protection against MmmSC infection has not yet been elucidated. On the other hand, the pathological lesions caused by the aetiological agent have been considered indicative of an immunopathological process. In this study ten naïve cattle were exposed to in-contact infection with animals infected by intubation with a strain of MmmSC. Clinical signs, antibody response, IFNg release and pathological changes at necropsy were analysed and compared with the events following in-contact infection of an equal number of animals kept under daily treatment with cyclosporine for the entire observation period of 84 days. Cyclosporine is a suppressor of the immune response related to the T-cell system. Under the conditions of the experiment, cyclosporine appeared to condition the pathogenesis of CBPP by delaying the events that follow infection, bringing further support to the possibility that the immune response may have an impact on the disease outcome.

European Union (EU) Directive 97/12/EC allows the trade of cattle within the EU of animals originating from an 'officially brucellosis-free herd'. To qualify for this status, a number of different programmes must be implemented. Each EU Member Country is free to decide which procedure to use to qualify herds. The authors conducted a study to compare the merits and costs of testing programmes given in the Directive and of some alternative testing strategies. The effectiveness of testing programmes was evaluated by a Monte Carlo simulation model. Programmes listed in the Directive do not appear to have identical sensitivity and specificity. Simulations of the programmes showed that milk testing may be more effective and efficient than blood testing to identify infected herds. Results indicated that it could be advisable that legislation, rather than defining very detailed procedures both for laboratory tests and testing programmes, should establish minimal requirements in terms of efficacy of testing procedures (i.e. the probability of detecting an infected herd).

In May 2011, dourine was reported in Italy following the declaration of a positive result observed in a stallion undergoing routine testing for stud purposes. Clinical signs, anatomo-histopathological findings and laboratory results that resulted in the confirmation of diagnosis of dourine in a clinically affected mare, which was the likely source of infection in the stallion, are described.

On 6th April 2009, at 3.32 AM, there was in L'Aquila and in some neighbouring villages, after an earthquake swarm last some months, an earthquake of M(L) = 5.8 (Richter magnitude scale) on depth of 8.8 km. The event was sensed in a very broad area, till in Rome and Ancon. The operative committee of the Civil Protection Department immediately gathered and a first operating group was despatched in the epicentre; the voluntary association of civil protection were in a pre-alarm situation and then were activated. This work want describe all the activities from 6th April 2009 till 31th August 2009, giving too a synthesis of the normative lines in case of catastrophic events typology C, otherwise all that events impossible to manage without national intervention.

Approximately 250,000 water buffalo (Bubalus bubalis) live in the Campania region of southern Italy where the breeding of this species is very popular. Of these animals, almost 150,000 are concentrated in the Caserta province where the prevalence of Brucella abortus in this species represents approximately 20% at herd level. The Italian brucellosis eradication programme provides a slaughter and vaccination strategy for this province. B. abortus strain RB51 (RB51) has become the official vaccine for the prevention of brucellosis in cattle in several countries. The aim of this study was to evaluate the efficacy of RB51 in water buffalo compared to the B. abortus S19 vaccine (S19). The study was performed in accordance with a protocol described in mice. Female buffalo aged five months were inoculated. Five received a RB51 dosage on two occasions that was three times greater than that approved for use in cattle and a booster after one month, five received B. abortus S19 vaccine at the standard dosage and three controls received a phosphate buffer solution. Buffalo were then challenged with a virulent B. abortus strain 544 thirty days post vaccination. Antibodies that developed in the five animals vaccinated with RB51 were not detected by the Rose Bengal test or complement fixation test (CFT) and were also tested by CFT prepared with RB51 antigen. After culling, B. abortus was cultured from the spleen, retropharyngeal and supra-mammary lymph nodes. A statistical evaluation was performed to assess the immunogenicity values obtained in buffalo vaccinated with S19, compared to those obtained in buffalo vaccinated with the RB51 vaccine and in the unvaccinated control group.

The Istituto Zooprofilattico Sperimentale dell'Abruzzo e del Molise 'G. Caporale' (IZS A&M) has been engaged for many years in research and studies designed to increase knowledge and expertise when dealing with 'exotic diseases' namely, those diseases which are not present in a country. To achieve these objectives, it is important to create cooperation networks with laboratories and research organisations at national and international levels. The relationship between the IZS A&M with Namibia in particular and, more recently with Botswana, are proving to be very valuable to mutual technical/scientific growth. In 2005, the National Reference Centre for the Study of Exotic Diseases set up its own Virology Laboratory at the Windhoek Central Veterinary Laboratory where the Namibian and IZS A&M personnel, working towards common goals, share diagnostic responsibilities and scientific research. The authors describe the activities involved in this joint project.

Immune response to Brucella abortus strain RB51 vaccine was measured in cattle vaccinated at calfhood. After an increase at day 6 post-vaccination (pv), the antibody level recorded in the 10 vaccinated animals remained constant for two months, and then progressively decreased. All vaccinated animals remained negative from day 162 pv to the end of the study (day 300 pv). Only at days 13 and 14 pv the RB51-CFT showed 100% sensitivity (credibility interval (CI) 76.2%-100%). The results indicate that the possibility to use RB51-CFT for the identification of cattle vaccinated at calfhood with RB51 is limited in time. A field investigation was carried out on 26,975 sera collected on regional basis from the Italian cattle population. The study outcomes indicate that in case of RB51-CFT positive results observed in officially Brucellosis-free (OBF) areas and, in any case, when an illegal use of RB51 vaccine is suspected, the use of the RB51-CFT alone is not sufficient to identify all the vaccinated animals. The design of a more sophisticated diagnostic protocol including an epidemiological investigation, the use of RB51-CFT, and the use of the skin test with RB51 as antigen is deemed more appropriate for the identification of RB51 vaccinated animals.

Transport can be a significant stress factor for livestock and can result in poor animal welfare and economic losses. Quality management measures are actively employed in fields different from animal welfare and could be applied to improve the welfare of animals and reduce the consequent losses during road transportation and related activities Training and education of staff comprise one possible measure, Web-geographic information system technology used to monitor the true state of transported animals is another innovation that promises major progress. With this technology, behavioural and environmental parameters can be monitored and registered in real time. The resulting data could be useful to control the transport environment and the conduct of staff. Although some parameters cannot be represented through numerical relationships, behavioural and environmental measurements can be used in a risk analysis system to minimise risks of poor welfare during animal transportation. The European Union Joint Research Centre and the Istituto Zooprofilattico Sperimentale dell'Abruzzo e del Molise 'G. Caporale' in Teramo are working on an experimental project to prove the feasibility of a navigation system for long road journeys as referred to in Regulation (EC) 1/2005 of the European Union. Such a system enables the collection of data on transported animals and the verification that welfare requirements are being met at any given moment during the journey.

The Authors describe an epidemiological survey performed after a cluster of cases of foodborne infection involving several participants at a wedding reception. The aim was to identify the food, the responsible pathogen and any shortcomings in the coordination between the various services and the territorial operating units involved in the outbreak investigation. The investigation involved 149 participants; fifty seven persons (38.3%) had a foodborne illness. The only food item that remained associated with illness after multiple regression analysis was the ricotta cheese (RR 3.58, I.C. 1.,72-7.48 ). The finding of B. cereus in samples of ricotta cheese collected at the dairy food supplier indicate its responsibility for the outbreak but diagnostic certainty could not be achieved as no leftovers were available. Thus, shortcomings in this epidemiological investigation are constituted by: delayed notification, which prevented the acquisition of food samples, lack of a reference laboratory and lack of a specific diagnostic protocols, which prevented the microbiological research for the rapid identification of new pathogens incriminated in foodborne diseases. Finally, environmental and sanitary inspections showed deficiencies in the hygienic measures of food storage, particularly regarding refrigeration and in the HACCP plan that was not properly implemented.

An indirect ELISA was evaluated for the detection of Brucella antibodies in milk (m-ELISA) from sheep experimentally infected with B. melitensis biovar 3. At the end of the second reproductive cycle (13 months post infection), the milk of 22 lactating sheep was tested using the m-ELISA. Sera from the same sheep were also tested for Brucella antibodies using the Rose Bengal test (RBT) and the complement fixation test (CFT). The first serum sampling after parturition showed 100% sensitivity in both the RBT and the CFT (confidence interval [CI] 94-100%), but in subsequent samplings the sensitivity of the RBT decreased to 73% (CI 55-85%). Similarly, the sensitivity of the CFT decreased two months after the first sampling, when respective sensitivities of 95% (CI 81-98%) and 81% (CI 61-93%) were recorded for the final two samplings. The sensitivity of the m-ELISA decreased initially (68% on the third sampling, CI 50-81%), but then increased to 95% (CI 81-98%) for the final sampling. When disease prevalence in a flock is below 5%, the estimated probability of not detecting an infected flock through m-ELISA bulk milk testing is over 25%. Under field conditions in Italy (average sheep flock size of 70), the probability that the infection will not be detected is over 25% when four (or less) infected milking sheep are present in the flock. The results show that the m-ELISA is not a reliable screening test for bulk milk samples when the prevalence of brucellosis in a sheep flock is low.

In the European Union, RB51 vaccine can be used only under strictly controlled conditions for the immunisation of cattle at risk of infection with Brucella abortus. A test is therefore necessary to distinguish vaccinated from unvaccinated animals. The complement fixation test with RB51 antigen (RB51-CFT), dot-blot and gamma-interferon used to identify vaccinated animals have been described, but sensitivity of the tests has been poor and positivity transient after calfhood vaccination. To avail of a rapid and accurate diagnostic tool, the authors produced, controlled and evaluated an experimental brucellin prepared from strain RB51 (RB51 brucellin). The potency of this brucellin was evaluated in guinea-pigs sensitised with RB51 and compared with a commercially available brucellin. Both allergens produced similar biological activity in guinea-pigs. The RB51 brucellin skin test was performed in 10 cattle 414 days after calfhood vaccination with RB51 when they were negative to the RB51-CFT. The skin test revealed 60% sensitivity (with a confidence interval of 95%, CI 30.8%-83.3%) and 100% specificity (CI 60.7%-100%). These findings limit the use of the skin test only for screening to detect RB51 vaccinated herds, not individual animals. Nevertheless, following intradermal inoculation of RB51 brucellin, a transient antibody increase to the RB51-CFT was observed, from day 9 to day 20 post inoculation with RB51 brucellin. This transient antibody increase, when evaluated in parallel with the RB51 brucellin skin test results, enables detection of individual vaccinated animals (sensitivity 100%; CI 76.2%-100%).

A challenge study was conducted to determine the efficacy of vaccination against bluetongue (BT) virus (BTV) serotype 2 in protecting cattle against infection. A group of 30 cows, vaccinated seven months previously with monovalent BTV-2 modified-live vaccine produced by Onderstepoort Biological Products in South Africa, were challenged subcutaneously with 2x 10(5.8)TCID50/ml of BTV-2 field isolate. All cattle originated from the same population in the Sardinian province of Oristano. Eight unvaccinated calves from a BTV-free herd also participated in this study; four were inoculated with BTV-2 and used as positive controls whilst the remaining four were used as negative controls to confirm that no BTV was circulating locally. Blood samples were taken from all animals three times a week for two months. Serum samples were tested for antibody against BTV using the competitive enzyme-linked immunosorbent assay (c-ELISA) and the virus neutralisation (VN) test. Virus isolation was attempted on the blood samples by intravenous egg inoculation followed by two blind passages in Vero cells. Virus titres following challenge were determined also. Of the 30 cows vaccinated, 29 were positive in the c-ELISA and demonstrated neutralising antibodies. At the time of challenge, 11 cows had no virus neutralising antibody while the remainder had low titres ranging from 1:10 (11 cows) to 1:20 (6 cows); two cows showed titres of 1:40 and 1:80, respectively. None of the cows showed signs of disease after challenge and no BTV was isolated from the blood of the 29 cows that had developed antibodies after vaccination. Commencing on day 9 post challenge, BTV-2 was isolated from the blood of the single cow that had not seroconverted following vaccination and from the blood of the unvaccinated controls. Viraemia lasted until day 21 post challenge. Neither BTV nor antibody was detected in the blood samples taken from the negative control group. These observations indicate that the monovalent BTV-2 modified-live vaccine protects most animals when challenged with field virus seven months post vaccination.

The antibody response following bluetongue (BT) vaccination under both field and experimental conditions, and the duration of colostral antibodies in calves born from vaccinated dams, were evaluated. To this end, 1 005 animals of various breeds and ages were selected at random from 10 herds in the Sardinian province of Oristano. During the first year of the vaccination campaign, the animals selected were vaccinated against BT virus (BTV) serotype 2 between July and August 2002. Blood samples were taken from all animals monthly for three months after vaccination and tested for the presence of BT antibodies using the competitive enzyme-linked immunosorbent assay (c-ELISA) and the virus neutralisation (VN) test. Serological results from field vaccinated animals were compared with those obtained following the vaccination of five animals under experimental conditions. Out of 1,005 animals, 994 (98.1%) developed BT antibody following vaccination whereas antibody was detected in all cows vaccinated under experimental conditions. Both groups showed the highest median titres of 1:160 after two months. To assess the duration of colostral antibodies in calves born from vaccinated dams, the sera of 47 calves were screened using the c-ELISA and VN test. Calves were divided into three age groups: Group A included 22 calves aged 1 to 25 days, Group B 13 calves aged 26 to 39 days and Group C 12 calves aged 40 to 60 days. Antibody was detected in calves in Groups A and B (68.2% and 46.1%, respectively) whereas the calves in Group C were serologically negative.

The incursion of bluetongue (BT) into Italy in August 2000 caused heavy economic losses, partly due to the disease itself, but mostly because of disruption caused to the national animal trade structure. To limit direct losses and the circulation of BT virus (BTV), the Italian Ministry of Health ordered, on 11 May 2001, the vaccination of all susceptible domestic ruminant species (i.e. sheep, goats, cattle and water buffalo) in both infected and surrounding areas. The vaccination strategy was based on a risk assessment that suggested it would prevent direct economic losses and significantly reduce virus circulation. Vaccination of the target animal populations commenced in January 2002, prior to the epidemic peak of BT that began in July 2002. The proportion of vaccinated animals differed between the various regions and the varying levels of vaccination of these populations had clear consequences on the occurrence of clinical disease and the spread of BTV infection. In those regions where more than 80% of the target population were properly vaccinated, the disease disappeared almost completely and virus circulation was reduced significantly. The importance of this reduced circulation of BTV (i.e. infection did not spread from affected areas) was immediately obvious in areas affected by the less virulent BTV serotype 9 where, despite the virtual absence of clinical disease, trade of animals to other areas was prohibited. The areas affected by the highly virulent BTV-2 also benefited from vaccination because it eliminated clinical disease while animal movements were prohibited. The main consequence of the reduction of virus circulation after vaccination, as documented by serological surveillance, was a significantly reduced expansion of the areas that were subjected to animal movement restrictions. Subsequently, analysis of surveillance data, coupled with specific risk assessments, led to a progressive relaxation of movement restrictions even in areas where the infection was still present but where most of the population had been adequately vaccinated. The effectiveness of the strategy used in Italy (i.e. vaccination of all domestic ruminants) was reinforced by extensive experimental and field studies. The aim of these studies was to: a) evaluate levels of individual and herd immunity and resistance to challenge conferred by vaccination, and b) quantify the frequency and severity of the adverse effects of vaccination on domestic ruminants. Ongoing research has focused on the ability of vaccination to suppress or reduce viraemia in ruminants following natural challenge by a virulent BTV strain. These studies address the issue of safety of the trade and movement of vaccinated animals that originate from areas in which BTV continues to circulate and could justify the reversal in current policy that restricts the international trade of animals vaccinated against BT.

As a consequence of the recent outbreaks of bluetongue (BT) disease amongst sheep in the Mediterranean Basin, and following the subsequent vaccination campaign to control further spread of the disease and its long-term maintenance, it has become most important to develop rapid and sensitive methods that can reliably differentiate between field and vaccine strains of the causative virus. The authors describe a new method to differentiate bluetongue virus serotype 2 (BTV-2) field and vaccine strains, using the VP2 gene sequence differences between the South African vaccine and the Italian field wild-type strains. The method is based on the principle that the melting temperature of a DNA duplex gives information on the sequence, which enables the identification of even single-base alterations in the amplicon. The real-time polymerase chain reaction the generation of melting curves and fluorescence detection were all performed using the light cycler system (Roche). Primers and probes were designed using VP2 gene sequences. After RT-PCR, the melting curves analysis, derived by the fluorescence resonance energy transfer (FRET) real-time PCR, was performed using the light cycler data analysis program (Roche). To assess the diagnostic value of the method, a BTV-2 vaccine strain (Onderstepoort Biological Products, South Africa) was first compared against a field strain of BTV-2 (isolated during an outbreak in 2000 in Sardinia). The ability of the method to reliably identify all the BTV-2 strains was tested using an array of eleven BTV-2 field strains isolated during outbreaks in various Italian regions between 2000 and 2002 and other serotypes (BTV-1, BTV-4, BTV-9 and BTV-16) that had been isolated during recent outbreaks of BT in the Mediterranean Basin. The method was clearly able to differentiate BTV-2 strains of vaccine virus from all wild-type strains of the same serotype tested. The resultant melting curves distinctly reveal the two strains to have differing peak values of 47.8 degrees C-/+0.6 degrees C and 60.5 degrees C-/+0.6 degrees C, respectively.

Since 1998, five serotypes of bluetongue virus (BTV), BTV-1, BTV-2, BTV-4, BTV-9 and BTV-16, have been reported in countries surrounding the Mediterranean Basin. Preliminary data on the sequencing analysis of the VP2-genes of BTV isolates recovered during the 1998-2002 epizootic of BT in Italy, Greece and Israel were studied. The VP2-genes of the Italian BTV-2 and BTV-9, Greek BTV-4 and BTV-9, Israeli BTV-4 and BTV-16 and South African BTV-2, BTV-4, BTV-9 and BTV-16, together with those of their corresponding South African serotype reference and vaccine strains, were cloned and the sequences of their terminal ends determined. These sequences, as well as those of all BTV VP2-gene sequences currently available on GenBank, were used to compile a phylogenetic tree to determine the probable geographic origins of the BTV incursions into Europe. The Italian isolates included in this study were from different regions, animal hosts and years (2000-2002). The results demonstrated that sequencing of the terminal end of the VP2-gene of BTV can be used for topotyping. According to the phylogenetic analysis, the Italian BTV-2 and BTV-9 isolates were stable across all species, irrespective of geographic origin and year of isolation. The sequencing data of the Italian isolates were identical to those of a BTV-2 isolate from Corsica. There was 97% homology between the Italian and Corsican BTV-2 isolates and the BTV-2 vaccine and reference isolates from South Africa. Italian BTV-9 isolates were also identical to the Greek BTV-9 isolates (99% homology). Surprisingly these BTV-9 isolates had only 67% homology with the reference BTV-9 isolate from South Africa. Conversely, BTV-9 field isolates from Australia and elsewhere in Europe had 89% homology with the Italian isolate at the nucleic acid level. Greek and Israeli BTV-4 isolates were almost identical (98% homology) and shared a 90% homology with the BTV-4 South African reference and vaccine strains. Israeli BTV-16 and South African BTV-16 reference strains were also similar. From these results, it may be concluded that Italian and Corsican BTV-2, Israeli and Greek BTV-4, and South African and Israeli BTV-16 had a common origin. The Greek BTV-9 isolate had more than 99% homology with the isolates from Italy, indicating these isolates to have had a common origin. The European BTV-9 isolates, grouped as 'eastern isolates', were more similar to the Australian isolates than to the South African reference strains.

An inactivated vaccine was produced from an Italian field isolate of bluetongue virus serotype 2 (BTV-2) with a titre of 10(7.8)TCID50/ml. The virus was purified through a molecular cut cassette membrane, inactivated with beta-propriolactone and emulsified with ISA 206 (Seppic) adjuvant. The vaccine was then tested for sterility, toxicity and safety in laboratory and target animals according to European Pharmacopoeia standards. Immunogenicity was assessed by inoculating subcutaneously 10 sheep and 10 goats each with 2 ml of the vaccine and 10 bovines each with 5 ml of the vaccine. A booster dose was inoculated after 14 days and no side-effects were reported following vaccination. Fourteen days after the booster dose, all vaccinated animals developed virus neutralising (VN) bluetongue (BT) antibody titres that on day 60 post vaccination ranged between 1/20 and 1/1 280. After one year, goats still had high VN antibody titres. Sheep were challenged 138 days after vaccination by subcutaneously inoculating 1 ml of 10(5.6)TCID50/ml of an Italian field isolate of BTV serotype 2; four unvaccinated animals were also inoculated and used as controls. Starting from day 6 post challenge, control animals developed a fever, with temperature ranging from 39.9 degrees C to 40.6 degrees C and lasting 48 h on average. BTV-2 was also isolated from the blood of control animals between days 4 and 20 post challenge. Conversely, neither fever nor viraemia were detected in the vaccinated animals that were challenged. A new trial with a larger number of animals, including all target species, has been planned and is in progress.

Between August 2000 and 14 May 2001 (defined as the 2000-2001 epidemic) bluetongue (BT) was reported in three regions of Italy: Sardinia, Sicily and Calabria. During the 2001-2002 epidemic (between 15 May and 14 April 2002), the disease spread to five additional regions (Puglia, Basilicata, Campania, Latium and Tuscany). In May 2001 the Italian Ministry of Health decided to restrict animal movements and to vaccinate all susceptible domestic ruminant populations in infected and in neighbouring regions. This action was taken to reduce virus circulation with the aim of decreasing direct losses in sheep and goats due to the disease, and indirect losses in cattle populations due to movement restrictions. Furthermore, the Italian authorities implemented an epidemiological surveillance system to monitor the spread of the virus and to provide more effective movement controls. In 2002, the vaccination campaign reached the set goal of vaccinating more than 80% of susceptible domestic ruminants in Abruzzo, Sardinia and Tuscany. The vaccination campaign successfully reduced clinical disease in Sardinia and Tuscany. Before the advent of BT, cattle had always been moved from Sardinia, Sicily and the southern regions for fattening and slaughter in northern Italy. During the tracing of animals that had left infected areas in 2000 it was found that 10 957 cattle had been exported from Sardinia between June and August 2000 and were scattered throughout continental Italy. In addition, most cows selected for culling from the southern regions and the islands were sent to northern Italy for slaughter. However, since August 2000 the animal trade between infected and free areas has come to a complete standstill. Sardinia, in particular, due to the climatic and epidemiological conditions (vectors survive almost throughout the year), was no longer able to export any ruminants to the mainland. Long-term standstill therefore led to heavy economic losses and had even greater social consequences. As farmers are not compensated, it is impossible to enforce these restrictions indefinitely. The Italian authorities and the European Commission thus decided to adopt a policy of risk management allowing some animal movement. This paper presents an analysis that assesses the risk associated with animal movement from restricted areas, according to the level of immunity of susceptible animal populations due to vaccination in the same areas. Results of the analysis indicate that when more than 80% of the susceptible population in the territory of origin is vaccinated, the risk associated with the movement of vaccinated animals to free areas appears acceptable and can be mitigated further by adopting ancillary control measures.

The first epidemic of bluetongue (BT) to affect the three regions of Sardinia, Sicily and Calabria (Italy) in 2000 induced high economic losses caused by the disease itself and by the cessation of ruminant movements both within, and out of, the infected areas. In order to reduce virus circulation, and to create a resistant livestock population, the Italian Ministry of Health ruled, in May 2001, that all sheep, cattle, goats and water buffalo, in infected and in neighbouring regions, be vaccinated. The live-attenuated BTV-2 monovalent vaccine produced by Onderstepoort Biological Products in South Africa was to be used. Accordingly, in 2002, 98.6% of the sheep and goats, and 88.1% of the cattle, on Sardinia were vaccinated. Included was the vaccination of >70% of the cattle in the province of Oristano where >18,000 dairy cows in >220 herds are concentrated in the municipality of Arborea (Oristano) and which account for 65-70% of the milk produced in Sardinia. Using data collected at the centralised dairy co-operative since 1999 the quantity and quality of milk produced before vaccination against bluetongue was compared to that produced after vaccination. The following variables were analysed: average milk production/cow/month, monthly average fat content (%), monthly average protein content (%), average monthly somatic cell count and average monthly platelet count. The findings indicate that vaccination against BTV-2 in Sardinian dairy cattle did not impact negatively upon milk quantity nor milk quality.

The occurrence of bluetongue (BT) in Italy prompted an increase in disease surveillance. Thus a competitive enzyme-linked immunosorbent assay (c-ELISA) to detect immunoglobulins to BT virus (BTV) was developed and distributed amongst 27 laboratories comprising the Italian veterinary diagnostic laboratories network to screen field sera. This ring test enabled comparison of the results and the evaluation of the reproducibility of the method. The c-ELISA developed by the National Reference Centre for Exotic Diseases (c-ELISA-IZSA&M) was compared also against a commercially available c-ELISA. In addition, results obtained by the Centre of Athens Veterinary Institutions are presented.

Transhumance, or seasonal grazing, in central Italy is a husbandry practice that is over two thousand years old. It involves the seasonal movement of sheep, goats and cattle from the southern lowlands of mainly the Puglia and Lazio regions, to summer pastures in the mountains of Abruzzo and Molise. Bluetongue (BT) made its appearance in Italy in 2000. In the early summer of 2001, disease was present in three regions: Sardinia, Sicily and Calabria. Neither an effective surveillance system nor a vaccination campaign had been implemented. Movement of ruminants to the disease-free regions of Abruzzo and Molise was therefore banned. The Italian Veterinary Services had to meet the challenge of the movement of ruminants from surveillance to disease-free zones, given the impossibility of stopping transhumance. The General Directorate of Veterinary Public Health, Food and Nutrition of the Ministry of Health developed a plan for both the Puglia and Abruzzo regions based on serological, virological and entomological surveillance. The plan was implemented between May and June 2001 when 7,000 animals moved from the Puglia surveillance zone to the infection-free summer pastures. In the early summer of 2002, eight regions were infected (Sardinia, Sicily, Calabria, Basilicata, Puglia, Campania, Lazio and Tuscany). Simultaneously, a nationwide surveillance system and a vaccination campaign, were implemented in infected regions. In the provinces where vaccination was compulsory, deviation from the animal movement ban was allowed if at least 80% of susceptible stock had been vaccinated. However, this objective was not achieved in the provinces of Rome and Viterbo (Lazio) where a large transhumant population was present and where sporadic virus circulation had been detected. A specific control plan to allow transhumance from Lazio to Abruzzo, Marche and Umbria was designed and implemented to increase the number of animals that could be moved. Between May and June 2002, authorisation was granted to move 28,000 head, whereas prohibition of movement was ordered for 12,000 sheep (belonging to 21 flocks). Regional authorities financed feeding, watering and housing for these animals. Transhumance did not spread infection to disease-free areas either in 2001 or in 2002.

Since the first appearance of bluetongue (BT) in Italy in late August 2000, the ecology of vectors and the environmental conditions affecting their distribution and survival proved to be the most difficult factors to monitor, and represented a serious challenge to the effectiveness of the National Contingency Plan promulgated in 1991. Moreover, the Italian Ministry of Health considered the national management plan of BT inadequate to prevent further spread of the disease. The authors describe the implementation of a new BT contingency plan, integrating an operations manual and an ad hoc information system, which operated also as a decision-support system both at local and central levels. The plan describes the national capacity for dealing with BT outbreaks, the composition and duties of the National Disease Control Centre and Local Disease Control Centres, the chain of command and the strategies adopted.

Since August 2000, Italy has lost almost 500,000 sheep to the largest incursion of bluetongue (BT) yet to affect Europe. The national BT surveillance system includes serological and entomological programmes. The main objective of the serological programme is the early detection of BT virus (BTV) circulation by periodical testing of more than 30,000 sentinel cattle distributed across Italy. The sentinel network has been in force since October 2001 and since its inception has provided accurate and timely detection of viral circulation. However, the repeated testing of such a large number of animals required significant effort from the Veterinary Services and was costly for farmers. Consequently, a Montecarlo simulation model was developed to simulate different sentinel system scenarios and the results from each were compared. The model was validated using data derived from the serological surveillance activities in Sardinia from October 2001 to December 2002.

The eastern focus of the current outbreak of bluetongue (BT) in the Mediterranean Basin commenced in late 1998, infecting Turkey and some of the eastern islands of Greece. In the summer of 1999 it moved to continental Greece and for the first time to Bulgaria. By the late summer of 2000, BT spread progressively through Greece and to the Balkan states. The BT virus (BTV) serotypes involved were BTV-4, BTV-9 and BTV-16. The west-central focus of the outbreak, involving BTV-2, appeared in Tunisia in December 1999 and the following summer also in Algeria. In August 2000, BTV-2 was reported for the first time in Italy (in Sardinia) and soon thereafter in France (Corsica) and in Spain (the Balearic Isles). In the autumn of 2000, a second serotype (BTV-9) emerged in southern peninsular Italy. Eventually this incursion of virus into the central Mediterranean region resulted in the largest epidemic of BT ever to affect Europe. Some features of this epidemic differ significantly from those observed previously, namely: a) its deep penetration northwards (reaching 44 degrees N both in Italy and in the Balkans) b) its persistence across four seasons in various zones of Italy and the Balkans, implying that BT could become endemic over a wide geographic area c) its successful invasion of areas separated from previously infected ones by fairly large distances (Sardinia, Sicily, Calabria, and the Balearic islands). The pattern of the spread of BT across Italy, before the introduction of vaccination, is described. The possible role of climate, soil and insect vectors on the incidence of the disease, and the overwintering of the virus, are discussed. Some hypotheses on the possible origins and modes of introduction of BTV into Italy are postulated.

The authors provide details of the bluetongue surveillance and the Internet-based information systems that were implemented in Italy. The systems were structured with the aim of gathering and spreading information and data to support decision-making, management of control activities and provide an early warning system. Information and data generated by the surveillance system enabled the detailed analysis of bluetongue epidemiology, vector distribution and vector population dynamics. This information and data also allowed the analysis of risk factors associated with vector spread and animal movements, which resulted in and increased the flexibility and the efficiency of the enforcement of control measures.

Between July and September 2002, bluetongue (BT) virus (BTV) serotypes 2 and 9 caused mortalities amongst sheep in the communities of San Gregorio Magno (Salerno, Campania), Laviano (Salerno, Campania) and Carpino (Foggia, Puglia), central Italy. On three of the affected farms, approximately 10,000 specimens of Culicoides were captured, representing fifteen species. Not a single specimen of the classical Afro-Asiatic BT vector, C. imicola Kieffer, was found; species of the Obsoletus Complex dominated the light-trap collections (90%) and included C. obsoletus (Meigen), C. scoticus Downes and Kettle and C. dewulfi Goetghebuer. Fifty-eight pools of the Obsoletus Complex (excluding C. dewulfi), each numbering 100 individuals per pool, and containing only parous and gravid females, were assayed for virus. BTV serotype 2 (BTV-2) was isolated from three pools (San Gregorio and Carpino) and BTV-9 from one (Laviano). These results indicate clearly that a species other than C. imicola is involved in the current re-emergence of BT in the Mediterranean Basin, but whether this is only C. obsoletus sensu stricto, or only C. scoticus, or both together, has yet to be established.

In summer 2000, bluetongue (BT) infection was reported in Italy and caused a widespread epidemic involving a total of ten southern and central regions and is still in progress after three years. From the date of the first case (18 August 2000) to 14 May 2001, when the lowpoint in the first epidemic curve was reached, a total of 310,234 animals in 6,869 flocks of three regions had been involved. From 15 May 2001 to 14 April 2002, when a second epidemic wave swept through central and southern Italy, a total of 323,635 animals in 6,807 flocks in seven regions were involved. During 2000 and 2001 virtually no susceptible ruminants were vaccinated. On 11 May 2001, the Italian Ministry of Health ordered the vaccination of all susceptible domestic ruminant species (i.e. sheep, goats, cattle and water buffalo) in the infected and surrounding areas. The vaccination strategy stemmed from a risk assessment that demonstrated the possibility of such a strategy preventing most of the direct economic losses and decreasing the level of virus circulation. Vaccination of the target populations commenced in January 2002. In July 2002, when the new epidemic peak was reached, the percentage of vaccinated populations varied between the regions with direct consequences on the spread of BT. The relationship between vaccination coverage of the target populations and animal losses due to disease and virus circulation, and as detected by the sentinel surveillance system, was analysed. The effectiveness of the vaccination campaign in limiting virus circulation and consequently indirect losses due to animal movement restrictions was analysed and evaluated. At the end of 2002, a second risk assessment led to the authorization of the movement of vaccinated animals from infected areas (where at least 80% of the susceptible population was vaccinated) directly to slaughter in unvaccinated areas free from infection. This risk assessment also generated new criteria to define zones where animal movement restrictions should be applied. Following the second vaccination campaign (January to May 2003), a third risk assessment was performed and the results from vaccination trials performed in controlled and in field conditions studied. These studies indicated that procedures to move vaccinated breeding animals from zones where infection exists to unvaccinated infection free zones could be contemplated.