National Eradication Programme Research Articles

Evaluating the effectiveness of badger vaccination combined with cattle test-and-removal in managing Bovine Tuberculosis: Insights from a two-host and multi-route transmission model

Bovine tuberculosis (bTB) has a complex infection ecology and is difficult to control in many countries, including Ireland. For many years, the Irish national bTB eradication programme relied on cattle-based control measures, including test-and-removal with related movement restrictions. In the early 2000s, badger culling was added as a part of the control measure in the national programme. As badgers are protected animals under Wildlife Acts, making culling undesirable, this practice is now progressively being replaced by badger vaccination. However, it is unclear whether badger vaccination, in combination with the cattle test-and-removal and movement restriction, is sufficient to eradicate bTB, or whether additional measures will be needed.Assessing the impact of badger vaccination on reducing bTB in cattle is complex due to the involvement of multiple hosts and transmission routes. Key contributors include transmission to and from wildlife (e.g., European badger, Meles meles), the persistence of Mycobacterium bovis in the environment, and – due to imperfect diagnostic tests - the movement of infected cattle and residual infection in the herd. Understanding of relative contribution of these infectious sources is a key knowledge gap. This study aims to assess the impact of badger vaccination, in addition to cattle test-and-removal and movement restriction, on bTB eradication at a regional level and to assess whether additional interventions are needed. Additionally, we investigate the contribution of several transmission mechanisms such as, local cattle, residual infection, badgers and introduced cattle on the transmission of bTB at the level of both the individual and the herd.To achieve this, we developed a metapopulation model that includes each of the above-mentioned transmission mechanisms for the Kilkenny badger vaccination trial area. The model incorporates within-herd transmission for cattle and within-territory transmission for badgers, and also transmission between herds, both via cattle trade movements and via overlapping badger territories. Our results show that cattle-to-cattle transmission contributes most to new cattle infections at the individual animal (cattle) level, while breakdowns at the herd level usually involve multiple routes. Badger vaccination, when combined with cattle test-and-removal programme, may not be sufficient to achieve eradication in this region. We highlight the need for additional interventions that target cattle, badger, and movement to form a comprehensive intervention strategy, including cattle vaccination, improve farm biosecurity, badger vaccination and risk-based trading.

Dutch BVDV Control Program - Evaluation 2018 - 2023.

Since 2018, Dutch dairy farmers are obliged to opt for one of 4 routes to achieve BVDV freedom in the national BVDV eradication program. This observational study evaluated efficacy of the total BVDV program using indicators such as number of persistent infected cattle (PI's), percentage of dairy herds with a BVDV-free status, percentage of BVDV-free dairy herds with evidence of introduction of BVDV and, as well as a cost calculation per route. The Dutch BVDV program appeared to be successful as the percentage of BVDV-free dairy herds increased from 59 percent at the start of the program to 89 percent by the end of 2023. The number of PI's detected each quarter, declined from 500 PI's in the third quarter of 2019 to 83 PI's in the last quarter of 2023. The percentage BVDV-free dairy herds with evidence of (re)introduction of BVDV decreased from 1.29 percent per quarter in the first year of the mandatory program to 0.25 percent per quarter by the end of 2023. In Europe, BVDV control program designs are often tailored to the country's specific situation e.g., prevalence at the start of eradication, risk profile of a country or herd, desired speed of eradication and available funds. These results show that the Dutch approach in which multiple routes can be followed toward BVDV freedom is successful.

Burden of HCV among Prevalent Haemodialysis Patients in Kafr Elsheikh after National Egyptian HCV Eradication Program

Abstract Background Hepatitis C Hepatitis C virus (HCV) infection is one of the most commonly reported viral infections in both developing and developed countries, causing significant mortality and morbidity and costing billions of dollars annually. The prevalence of HCV infection in hemodialysis patients varies substantially among different geographical regions. Recent studies have shown that the HCV prevalence in hemodialysis patients varies from 1.4%–28.3% in developed countries and 4.7%–41.9% in developing countries Aim of the Work to estimate the prevalence of HCV infection and to determine the seroconversion rate in prevelant hemodilaysis in Kafr Elsheikh governorate after the hepatitis C virus infection National eradication program in Egypt and to identify the demographics leading to then non-compliance to hepatitis C virus medications and missed follow up among the prevalent hemodialysis patients with HCV infection in Kafr EL sheikh governorate, Egypt. Patients and Methods All patients were assessed for eligibility criteria and were included in the study only when they had met the following inclusion criteria: age older than 18 years old, maintained on regular hemodialysis session for more than 3 months. On the other hand, the exclusion criteria encompassed patients with acute kidney injury or any conditions necessitating temporary dialysis or patient age is less than 18 years old. 1162 prevalent hemodialysis patients in kafr el sheikh governorate, Egypt have been enrolled at our cross sectional study (multi-centric study) applying the proposed standards of the inclusion and exclusion criteria of our study design. Results Among these 1162 patients, 403 patients (34.68%) had history of positive PCR for HCV infection prior and during the national eradication campaign. Among those patients, 212 patients (52.61%) received HCV infection treatment in the form of oral and parenteral medications, while 191 patients (47.39%) didn't receive treatment. Among the patients who didn't receive the prescribed medications for HCV virus, 107 patients (56.02%) had concerns about drug complications, 22 patients didn't receive the prescribed medication due to lack of counselling while 20 patients (10.47%) did not receive treatment due to other causes as being mentally retarded, or having advanced medical comorbidities as advanced liver disease or decompensated heart failure while 42 patients (21.99%) refused to receive treatment without giving reasons. Conclusion The prevalence of HCV infection among the studied prevalent hemodialysis patients in Kafr El-Sheikh governorate is 19.4% after the HCV national eradication protocol and can be considered a major health problem. A significant percentage of the prevalent hemodialysis patients with hepatitis C virus infection refused to apply to the prescribed antiviral medications or being non complaint on medication that was mostly due to fear of developed major side effects of the prescribed medications and lack of counselling.

Floods and fire ants, Solenopsis invicta (Hymenoptera: Formicidae): the Australian experience

AbstractThe rafting behaviour of the red imported fire ant, Solenopsis invicta, in response to flooding events is well documented, although studies generally have focussed on the mechanisms of raft assembly and the behaviour of the raft's occupants. Flooding as a means of dispersal of S. invicta is frequently mentioned in the literature, although there are few data on the distances travelled or how effective it is compared to natural flight. In Australia, S. invicta is a priority invasive species with a national eradication program operating for 23 years, focussed on the population in southeast Queensland, which currently encompasses more than 700 000 ha. Flooding presents a risk to the success of the program through extending the infestation area or recolonising successfully treated areas. We used the program's extensive spatiotemporal dataset of known fire ant colony locations to assess the effects of two significant flood events on the dispersal or displacement of S. invicta in Queensland. Results indicated that flooding did not spread S. invicta beyond the known boundaries of infestation but contributed to localised spread, particularly for sites with known polygyne infestations. This situation could change if the ant spreads to new river catchments. A novel method developed to assess the risk of S. invicta dispersal through flooding is presented, alongside program actions that can be applied to mitigate this risk.

Spatiotemporal Distribution of PRRSV-1 Clades in Hungary with a Focus on the Era of Disease Eradication.

Porcine reproductive and respiratory syndrome (PRRS) is the cause of the most severe economic losses in the pig industry worldwide. PRRSV is extremely diverse in Europe, which poses a significant challenge to disease control within a country or any region. With the combination of phylogenetic reconstruction and network analysis, we aimed to uncover the major routes of the dispersal of PRRSV clades within Hungary. In brief, by analyzing >2600 ORF5 sequences, we identified at least 12 clades (including 6 clades within lineage 1 and 3 clades within lineage 3) common in parts of Western Europe (including Denmark, Germany and the Netherlands) and identified 2 novel clades (designated X1 and X2). Of interest, some genetic clades unique to other central European countries, such as the Czech Republic and Poland, were not identified. The pattern of PRRSV clade distribution is consistent with the route of the pig trade among countries, showing that most of the identified clades were introduced from Western Europe when fatteners were transported to Hungary. As a result of rigorous implementation of the national eradication program, the swine population was declared officially free from PRRSV. This map of viral diversity and clade distribution will serve as valuable baseline information for the maintenance of PRRSV-free status in the post-eradication era.

Epidemiological situation of bovine and bubaline tuberculosis in the state of Pará, Amazon region of Brazil.

Bovine tuberculosis is one of the primary infectious diseases affecting cattle. Although several countries have managed to eradicate this zoonosis it remains endemic and uncontrolled across many countries in Africa, Asia, Latin America, and the Middle East. Brazil launched its national control and eradication program in 2001, and since then, epidemiological studies have been carried out to define optimal control strategies and to enable the management of the process in each region. This study covered the state of Pará, which was divided into three regions, in each of which a pre-established number of properties were randomly selected, and within each property, a minimum number of animals were drawn to be tested by the tuberculin test to classify the farm as infected or free of the disease. A questionnaire was administered to the selected properties to identify the risk factors for the disease. A total of 976 properties comprising 17,151 animals were tested. The prevalence of infected properties in the regions ranged from 3.1% [1.3; 4.9] to 18.6% [14.3; 22.9], while tuberculin-positive animals ranged from 0.24% [0.09; 0.40] to 4.8% [2.4; 7.3]. The introduction of cattle untested for bTB and the renting of pastures have been identified as risk factors for the disease in this state. Pará has one of the highest prevalences of bovine tuberculosis in Brazil, and the implications of these results for public health were discussed. We therefore proposed that the state's Official Veterinary Service, together with the private dairy and meat sectors, pursue the objective of controlling or eradicating the disease, along with mechanisms to verify its effectiveness. The differences between the two objectives were discussed, but in both cases, an education program is necessary to inform cattle and buffalo breeders that they need to test animals for tuberculosis before introducing them to their farms, and also to avoid renting pastures for cattle to graze and rest while moving on foot, as these practices have contributed the most to the spread of bTB in the state.

Experimental use of mycobacterial antigens in tuberculin skin test on water buffalo

In Italy, bovine tuberculosis (TB) control in the water buffalo population is mainly carried out using the tuberculin skin test (TST). The test measures the increase in skin thickness 72 hours (h) after the intradermal injection of mycobacterial purified protein derivatives (PPD). The TST can involve the single intradermal test with bovine PPD (PPDB), or the comparative test adding a second injection with avian tuberculin (PPDA), using the couple of PPDs reduces false positives caused by non-tuberculosis mycobacteria. This pilot study aimed to evaluate the potential use of PPDB, PPDA, along with 6 kDa early secretory antigenic target (ESAT-6), 10 kDa culture filtrate protein (CFP-10), and Early Secretory Proteins (ESP) in the TST, in healthy and naturally TB infected buffaloes. Twenty-one buffaloes, gamma-interferon (IFN-γ) test positive, from a TB-out-break herd and 11 buffaloes from a TB-free herd were selected. All subjects were also submitted to the IFN-γ test using the same antigens (Ag) as the TST to verify the cellular response in vitro and to exclude anaergic animals that did not respond to in vitro stimulation with the mitogen. The TST was performed according to the TB Italian National eradication program, and to Reg. EU 2020/689. Eight intradermal injection sites were used on each animal shoulder (4 on the right and 4 on the left side). Three concentrations of the ESAT6-CFP10 protein cocktail (10, 20 and 30 μg) and two of ESP (50 and 100 μg) were inoculated. PPDB and PPDA were always included in the TST, along with PBS as negative control. Skin reactions were measured with calipers before the test and every 24 h for 4 days. The TST was considered positive in animals with an increase in skin thickness between post and pre-dermal test readings of > 4 mm, doubtful if between 2 and 4 mm, negative <2 mm. Negative subjects also exhibited a skin response to PPDB at 24 and 48 h, but it became completely negative at 72 h, the prescribed reading time. In the positive buffaloes, the kinetics of skin responses showed that the strongest response was to PPDB at 24h, with some subjects becoming doubtful at 72 and 96 h. A peak response was observed at 48 hours to PPDA and to 20 μg of the ESAT6-CFP10 protein cocktail, followed by a decrease. The response to ESP-100 μg remained high at 24 and 48 h and then decreased, remaining positive at 72 h. ESP showed the best performance with higher reactivity in positive animals and no reactivity in negative animals at 72 h. Therefore, ESP could be an excellent candidate for further extensive studies in the buffalo species to improve TST Sensitivity and Specificity.

Scenarios warranting modified treatment regimens in leprosy: A 5-year retrospective study from a tertiary care center

Objectives: To study the scenarios warranting modified treatment regimens in leprosy. Materials and Methods: A 5-year retrospective study was carried out in a tertiary care center by analyzing the data collected from national leprosy eradication program (NLEP) records. Results: During the 5-year study period, 171 patients received treatment for leprosy from our center. Thirtyone patients (31/171, 18.1%) required substitution of standard multidrug therapy (MDT) with alternate drugs or required alternate treatment regimens. The patients who required modified treatment included 18 men (18/31, 58.1%) and 13 women (41.9%). Male/female ratio was 1.4:1. Indications for treatment modification were adverse drug reactions to standard MDT (ADR) (21/31, 67.7%) and lack of response to standard MDT (10/31, 32.3%). The most common scenario that warranted a modification of standard MDT was dapsone-induced hemolysis (12/31, 38.7%). Seven (7/31, 22.6%) and two (2/31, 6.5%) patients needed a change in treatment due to drug-induced hepatitis and drug-induced maculopapular rash, respectively. Limitations: Retrospective study design, study conducted in single tertiary referral center and small sample size were the limitations. Conclusion: Nearly one-fifth of patients with leprosy required modifications in standard MDT. The most common indication (in two-third of patients who needed a modified treatment) for modification of treatment regimen was adverse drug reactions.

Sex-based differences in the distribution of Aujeszky’s disease-seropositive Japanese wild boar

BackgroundAujeszky’s disease virus (ADV) primarily infects domestic pigs and wild boars, causing the abortion and death of young piglets due to central nervous system disorders. In Japan, the national eradication program for ADV in domestic pigs has been successful in most prefectures; however, concern has been raised regarding ADV-infected wild boars as a source of transmission to domestic pigs.ResultsWe assessed the nationwide seroprevalence of ADV among wild boars (Sus scrofa) in Japan. Moreover, we determined the sex-based differences in the spatial clustering of seropositive animals. Serum samples were obtained from a total of 1383 wild boars acquired by hunting in 41 prefectures in three fiscal years (April–March in 2014, 2015, and 2017). Seropositivity tests for ADV using enzyme-linked immunosorbent assay, the latex agglutination and neutralization tests showed 29 boars seropositive for ADV (29/1383, 2.1% [95% confidence interval, CI: 1.4–3.0%]), with 28 of these boars originating from three prefectures in the Kii Peninsula (28/121, 23.1% [95% CI: 16.0–31.7%]). The degree of spatial clustering of these ADV-seropositive adult boars in the Kii Peninsula was evaluated using the K-function and data from sera samples of 46 (14 seropositive) male and 54 (12 seropositive) female boars. The degree of clustering among females was significantly higher in seropositive animals than in tested animals; however, such a difference was not observed for seropositive males.ConclusionsThe spatial dynamics of ADV among adult wild boars may be characterized based on sex, and is likely due to sex-based differences in behavioral patterns including dispersal among wild boars.

Invited review: Bovine abortion-Incidence, risk factors and causes.

The true incidence of bovine abortion (42-260 days of gestation) is unknown because of under-reporting. This is particularly true of the first half of gestation when most abortions occur. From research studies, it is estimated that the animal-level incidence of abortion between day 45 and term is approximately 10%, being lower in suckler than in dairy cows. While wide variation exists in herd-level incidence, up to 30%, it is estimated that less than 5% of farmers report high (>5%) observed abortion rates. Given these figures, veterinary practitioners and farmers tend to use investigation thresholds close to these values, ≥5 and ≥3%, respectively. Most of the risk factors for abortion are animal-level factors (e.g. parity), but there are also herd-level factors (e.g. enterprise type). Of the many risk factors for bovine abortion, only a small number are modifiable. While the causes of bovine abortion are often classified as noninfectious or infectious, in reality, this means diagnosis not reached (DNR) or infectious. Approximately 40% of abortions are diagnosed as infectious and the remaining 60% as DNR; DNR includes both infectious and noninfectious causes not diagnosed. Increasingly, genetic causes are being diagnosed and changes to current national genetic selection indices may be warranted. Of the infectious causes, Neospora caninum is now the most commonly diagnosed abortifacient internationally, followed by Trueperella pyogenes, BVDv and fungi. Both national eradication programmes and effective vaccination programmes can reduce the burden of some infectious abortifacients, but the control of sporadic, noninfectious and Neospora-associated abortions remains challenging.

Evaluation of the accuracy of the IDvet serological test for Mycoplasma bovis infection in cattle using latent class analysis of paired serum ELISA and quantitative real-time PCR on tonsillar swabs sampled at slaughter.

Mycoplasma bovis (Mbovis) was first detected in cattle in New Zealand (NZ) in July 2017. To prevent further spread, NZ launched a world-first National Eradication Programme in May 2018. Existing diagnostic tests for Mbovis have been applied in countries where Mbovis is endemic, for detecting infection following outbreaks of clinical disease. Diagnostic test evaluation (DTE) under NZ conditions was thus required to inform the Programme. We used Bayesian Latent Class Analysis on paired serum ELISA (ID Screen Mycoplasma bovis Indirect from IDvet) and tonsillar swabs (qPCR) for DTE in the absence of a gold standard. Tested samples were collected at slaughter between June 2018 and November 2019, from infected herds depopulated by the Programme. A first set of models evaluated the detection of active infection, i.e. the presence of Mbovis in the host. At a modified serology positivity threshold of SP%> = 90, estimates of animal-level ELISA sensitivity was 72.8% (95% credible interval 68.5%-77.4%), respectively 97.7% (95% credible interval 97.3%-98.1%) for specificity, while the qPCR sensitivity was 45.2% (95% credible interval 41.0%-49.8%), respectively 99.6% (95% credible interval 99.4%-99.8%) for specificity. In a second set of models, prior information about ELISA specificity was obtained from the National Beef Cattle Surveillance Programme, a population theoretically free-or very low prevalence-of Mbovis. These analyses aimed to evaluate the accuracy of the ELISA test targeting prior exposure to Mbovis, rather than active infection. The specificity of the ELISA for detecting exposure to Mbovis was 99.9% (95% credible interval 99.7%-100.0%), hence near perfect at the threshold SP%=90. This specificity estimate, considerably higher than in the first set of models, was equivalent to the manufacturer's estimate. The corresponding ELISA sensitivity estimate was 66.0% (95% credible interval 62.7%-70.7%). These results confirm that the IDvet ELISA test is an appropriate tool for determining exposure and infection status of herds, both to delimit and confirm the absence of Mbovis.

The Impact of PRRS Eradication Program on the Production Parameters of the Hungarian Swine Sector.

The Hungarian national eradication program of PRRS was successfully completed between 2014 and 2022. There were doubts about the efficiency of the eradication program in Hungary from the beginning to the tune that it might only be carried out efficiently through depopulation-repopulation of the infected herds, which is a very costly procedure. In our study, we investigated the impact of the depopulation-repopulation procedure, which played a prominent role in the PRRS eradication program on the productivity of the Hungarian swine sector-namely, on the number of slaughter pigs per sow per year and the total live slaughter weight per sow per year. Since 2014, we monitored the evolution of the PRRS eradication through the depopulation-repopulation approach on the large-scale breeding herds in Hungary. Most producers replaced their herds with animals that were free of PRRS and other infectious diseases (mycoplasmosis, actinobacillosis, swine dysentery, atrophic rhinitis, etc.). On this basis, we evaluated the change in the number of slaughter pigs per sow per year as a consequence of depopulation-repopulation of the herds being carried out. In the statistical analysis linear regression was used. The results of our study demonstrate that the PRRS eradication program with the herd depopulation-repopulation approach led to a considerable improvement of the productivity of Hungarian pig farming. This result also demonstrates that, independent of the PRRS eradication, it is still necessary to consider investments into the individual production units to increase efficiency, and to carry out herd depopulation-repopulation in cases where the current genetics limits improvements in productivity.

Bovine Tuberculosis - Analysis of 10-year cases and impact of visual inspection in the surveillance at the slaughterhouse in Portugal

Bovine Tuberculosis (bTB) is a One Health issue that interconnects human health with animal and environmental health. Due to its importance, cattle (the main host) it is under a national eradication programme in Portugal. Within it, meat inspection is considered a cost-effective procedure in bTB surveillance. The Commission's Implementing Regulation (EU) 2019/627 changed the post-mortem meat inspection requirements applied to cattle, essentially reducing handling and incisions in young cattle (<8 months). To study the impact of these changes on the surveillance of bovine Tuberculosis, data (age, sex, fitness, breed, lesions, laboratory results and post-mortem decisions) on suspected and confirmed cases of bTB detected at routine slaughter of the period from October 2010 to January 2020 were analysed.From a total of 3,279,548 slaughtered animals, meat inspection detected 808 suspected cases. Of these, 381 cases were laboratory confirmed. The estimated global prevalence was 11.6 cases/100,000, increasing with age: 3.5, 5.9 and 27.3 cases/100,000 in, respectively, the groups <8 months, 8 to 19 months, and ≥ 20 months. The prevalence was higher in females (16.3 vs 7.3 cases/100,000 in males) and in beef cattle (16.3 vs 1.4 cases/100,000 in dairy cattle). Among the confirmed cases, mediastinal and bronchial lymph nodes were the most reported locations. Based on the results, there is no evidence of a negative impact on the application of Regulation (EU) 2019/627 on bTB surveillance in animals ≥8 months. For the <8 months group the change to a visual inspection protocol could lead to a failure in the detection of bTB cases. Considering the epidemiological situation, the incision of the mediastinal, bronchial and retropharyngeal lymph nodes in cattle <8 months should be maintained.

Augmentative Releases of Two Diachasmimorpha longicaudata (Hymenoptera: Braconidae) Population Lines Under Field-Cage Conditions to Control Ceratitis capitata (Diptera: Tephritidae).

Ceratitis capitata (Wiedemann) (Diptera: Tephritidae), known as Medfly, is a severe agricultural invasive pest in Argentinian fruit-producing regions. The native habitat disturbance and introduction and spread of exotic host plants strongly favored Medfly proliferation. This scenario is common throughout the northern subtropical citrus-growing region. Environmentally friendly strategies to suppress Medfly populations by the National Fruit Fly Control and Eradication Program have currently been taken. One of these actions involves augmentative biological control through releases of the exotic parasitoid Diachasmimorpha longicaudata (Ashmead) (Hymenoptera: Braconidae). Consequently, the hypothesis that the effectiveness of D. longicaudata females, from two different population lines, in controlling Medfly larvae progressively increases as the density of released females increases was tested. One parasitoid line derives from larvae of a biparental Medfly strain. The other hails from irradiated larvae of the genetic sexing Temperature Sensitive Lethal Vienna-8 medfly strain reared at the "BioPlanta San Juan" biofactory. Parasitoids foraged for 24h on peaches artificially inoculated with naked lab-reared biparental Medfly larvae. Peaches were placed near the roof or on the ground in field cages. Five treatments (20, 40, 80, 160, and 320 females released) and a control (no parasitoids) for each population line were carried out throughout summer and autumn 2016. Host density (200 larvae) remained constant. At 320 released parasitoid females, both D. longicaudata population lines highly increased the Medfly mortality in both testing seasons, and foraged skillfully on peaches at both fruit height levels. These data encourage the application of augmentative biological control against Medfly.

BVD seroprevalence in the Irish cattle population as the national BVD programme progresses toward eradication

BackgroundBovine Viral Diarrhoea Virus (BVDV) infection remains endemic in many countries worldwide. Ireland, in common with several other European counties, commenced an BVDV eradication programme in the last decade, Managing eradication programmes requires careful monitoring of diseases prevalence and understanding factors associated with disease exposure to ensure eradication programmes remain evidence based and tailored to the evolving epidemiological situation.MethodsIn this study, we explore the seroprevalence of BVDV exposure over a four-year period (2017 to 2020) in Ireland from a cohort of animals (n = 6,449) under 30 months of age sampled at slaughter, who were born subsequent to the commencement of a compulsory national eradication programme. Temporal trends and risk factor analysis were undertaken using multilevel logit regression models.ResultsThere was a declining temporal trend in seroprevalence over the sample years of the study, and risk varied at both county- and herd-levels. The unadjusted marginal animal-level seroprevalence reduced from 9.1% in 2017 (95%; CI: 7.2—10.9) to 3.9% in 2020 (95%; CI: 3.2—4.6). The final model suggested that seropositivity in study cattle was strongly related with the presence of a PI animal in the herd during the year of the animal’s birth, and to a lesser extent the status of the herd from which the animal was slaughtered. The risk of seroconversion increased significantly with increasing size of the herd of slaughter, in females relative to males, and in dairy relative to suckler herds.ConclusionsThis study has shown that the BVDV serostatus of cattle at slaughter is correlated to the BVD infection history of the herd into which the animal was born and the herd from which it was slaughtered. Herd location, increased herd size and dairy production were associated with increased probability of serconversion. These findings will be used to inform the targeting of surveillance strategies once BVDV freedom has been achieved.

Bovine brucellosis serological survey in small dairy herds in Lushnja district, Albania

Bovine brucellosis is an important zoonotic disease in Albania. Both B. abortus and B. melitensis have been isolated from ruminants. National control and eradication programs for brucellosis are applied on sheep and goat farms and larger dairy cattle farms. However, the current control programs for brucellosis do not cover small dairy cattle farms, and there is no valid data on the prevalence of the disease in this category; this prevents formulating evidence-based and effective strategies for control of the disease in this population subset. Therefore, the current study aimed to assess the herd and within-herd prevalence of bovine brucellosis in small bovine herds and provide scientific evidence for establishing an evidence-based approach to control the disease in this subset of the population not previously included in the national eradication program. To achieve this objective, a statistical survey was designed and implemented in small dairy herds in the Lushnja district, where samples from statistically selected herds were serologically tested in parallel with Rose Bengal Test (RBT), Fluorescence Polarization Assay (FPA) and Enzyme-Linked Immunosorbent Assay (ELISA). In total, 120 dairy herds were randomly selected from a list of 1,955 registered herds: from these selected herds, 368 blood samples were collected from all animals older than 12 months, and their sera were tested using RBT, FPA, and c-ELISA. The test results revealed no positive or suspect cases. Based on these results, we are confident (P0.05) that Brucella spp is not circulating in this subpopulation of cattle in the Lushja district. This deduction is supported by analyses of the main risk factors, other epidemiological data, and the perceptions of official and private veterinarians. This is the first structured survey of bovine brucellosis in small dairy herds in Albania. In conclusion, our study results and our findings show that the epidemiological status of bovine brucellosis in the Lushnja district is encouraging. Therefore, a test and slaughter control program appears appropriate in smaller herds. Furthermore, the approach used in this pilot study could be extended to establish the prevalence of brucellosis in other districts, the result of which would establish the basis for rational control measures in the smaller herds of cattle.

Evaluating the risk of bovine tuberculosis posed by standard inconclusive reactors identified at backward-traced herd tests in Northern Ireland that disclosed no reactors

Bovine tuberculosis is a notifiable disease in Northern Ireland with the national eradication programme of compulsory testing and slaughter of reactor animals costing approximately £40 million per year. Backward tracing, known as Backward Check Tests (BCTs), of reactor animals is used to identify previous herds where the bTB positive animal has resided. The aim of this study was to quantify the bovine tuberculosis (bTB) risk posed by inconclusive reactors (ICs) at BCTs at both the individual animal and the herd level. ICs to the Comparative Intradermal Tuberculin Test (CITT) at a BCT, in which no reactors were found, were matched with CITT negative animals, based on age, sex, test ID and follow up period, in Northern Ireland between 1st January 2008 and 31st December 2017 (inclusive). A retrospective matched cohort study design was used with the outcome of interest being the bTB status of each animal and subsequent bTB herd breakdowns. After adjusting for herd size, IC animals at a BCT had 16 times the odds (95% confidence interval: 7.75 to 38.28, p < 0.001) of becoming bTB positive compared to CITT negative animals. The percentage population attributable risk was 0.0001%. The majority 75% (n = 71) of ICs that became bTB positive were identified at the 42 day retest. Of those that were not disclosed at the 42 day retest (n = 24), almost a third (29%) had moved to an unrestricted herd. However, after adjusting for herd size and type, herds that had ICs only identified at a BCT did not have an increased odds of a subsequent bTB herd breakdown compared to herds that had a CITT negative BCT. Given the increased risk posed by ICs at a BCT, it may be justifiable to remove them from the herd immediately or place them under lifetime movement restrictions to the herd where they were detected. However, further action regarding the herd of origin does not appear to be justified.

Analysis of the effectiveness of animal rabies control measures in Ukraine

The aim of the study was to evaluate the effectiveness of anti-epizootic measures to combat animal rabies, which were carried out in Ukraine in 2018–2020. Materials of official veterinary reporting, report of the Accounts Chamber of Ukraine, reports on the assessment of the risk of rabies spread among domestic, farm and wild animals, information from the EU Reference Laboratories regarding rabies and wildlife, information from the internet resource Rabies-Bulletin-Europe, European Commission reports on the implementation of national rabies eradication programs in the EU were used for the analysis. It has been found that the lack of the identification of domestic carnivores is a probable factor of incomplete coverage of rabies parenteral vaccination of dogs and cats, despite 100% implementation of anti-epizootic plans. It has been found that campaigns of oral immunization of wild carnivores against rabies were carried out once a year (in autumn), not twice a year (in spring and autumn), which had a significant negative impact on the effectiveness of this anti-epizootic measure. Despite the identified shortcomings, the result of the campaigns of oral vaccination of wild carnivores against rabies was a twice decrease of rabies cases among the target groups of animals in the period 2018–2020. Anti-epizootic measures to control rabies of animal in 2018–2020 were carried out using national regulatory standards and the organizational and technical means of the State Food and Consumer Service. Based on the results of the assessment of anti rabies measures carried out in 2018–2020, a number of regulatory, technical and organizational recommendations have been proposed. The implementation of these recommendations will make it possible to increase the effectiveness of rabies control in Ukraine

African Swine Fever in Wild Boar (Poland 2020): Passive and Active Surveillance Analysis and Further Perspectives.

African swine fever (ASF) is a fatal hemorrhagic disease of wild boar and domestic pigs which has been present in Poland since 2014. By 2020, the ASF virus (ASFV) spread across Central, Eastern and Western Europe (including Germany), and Asian countries (including China, Vietnam, and South Korea). The national ASF eradication and prevention program includes continuous passive (wild boar found dead and road-killed wild boar) and active (hunted wild boar) surveillance. The main goal of this study was to analyze the dynamic of the spread of ASF in the wild boar population across the territory of Poland in 2020. In that year in Poland, in total 6191 ASF-positive wild boar were declared. Most of them were confirmed in a group of animals found dead. The conducted statistical analysis indicates that the highest chance of obtaining an ASF-positive result in wild boar was during the winter months, from January to March, and in December 2020. Despite the biosecurity measures implemented by holdings of domestic pigs, the disease also occurred in 109 pig farms. The role of ASF surveillance in the wild boar population is crucial to apply more effective and tailored measures of disease control and eradication. The most essential measures to maintain sustainable production of domestic pigs in Poland include effective management of the wild boar population, along with strict implementation of biosecurity measures by domestic pig producers.

Genetic Variability of PRRSV Vaccine Strains Used in the National Eradication Programme, Hungary.

Porcine reproductive and respiratory syndrome (PRRS) is a globally spread, highly infectious viral disease. Live, attenuated vaccines against PRRS virus (PRRSV) decrease virus excretion and evoke protective immunity reducing the economic damage caused by the disease. In a longitudinal molecular epidemiological study accompanying ongoing national eradication programme we evaluated the suitability of PRRSV ORF5 and ORF7 sequences to identify possible field strains of vaccine-origin. In total, 2342 ORF5 sequences and 478 ORF7 sequences were analysed. Vaccine strains were identified by sequence identity values and phylogenetic network analysis. Strains that shared greater than 98% nucleotide identity within ORF5 and/or ORF7 were considered to have originated from vaccine. A total of 882 (37.6%) ORF5 and 88 (18.4%) ORF7 sequences met these criteria. In detail, 618, 179 and 35 ORF5 and 51, 29 and 8 ORF7 sequences were related to Porcilis PRRS vaccine, Unistrain PRRS vaccine, and ReproCyc PRRS EU vaccine, respectively. Data showed that the Porcilis vaccine was genetically more stable. Whereas, the variability of the Unistrain and the ReproCyc strains was significantly higher. Given that ORF7 shares, in some instances, complete identity between a particular vaccine strain and some historic variants of field PRRSV strains, care must be taken when evaluating vaccine relatedness of a field isolate based on the ORF7. On the contrary, ORF5 sequences were more suitable to predict the vaccine origin making a distinction more robustly between field and vaccine strains. We conclude that ORF5 based molecular epidemiological studies support more efficiently the ongoing PRRS eradication programmes. The conclusions presented in this large-scale PRRS molecular epidemiological study provides a framework for future eradication programmes planned in other countries.