Evaluation of the risk factors contributing to the African swine fever occurrence in Sardinia, Italy

This study assesses the relation between hypothesized risk factors and African swine fever virus (ASFV) distribution in Sardinia (Italy) after the beginning of the eradication program in 1993, using a Bayesian multivariable logistic regression mixed model. Results indicate that the probability of ASFV occurrence in Sardinia was associated to particular socio-cultural, productive and economical factors found in the region, particularly to large number of confined (i.e., closed) farms (most of them backyard), high road density, high mean altitude, large number of open fattening farms, and large number of pigs per commune. Conversely, large proportion of open farms with at least one census and large proportion of open farms per commune, were found to be protective factors for ASFV. Results suggest that basic preventive and control strategies, such as yearly census or registration of the pigs per farm and better control of the public lands where pigs are usually raised, together with endanced effords of outreach and communication with pig producers should help in the success of the eradication program for ASF in the Island. Methods and results presented here will inform decision making to better control and eradicate ASF in Sardinia and in all those areas with similar management and epidemiological conditions

Predictors of Bluetongue development in Sardinia (Italy) identification, using multilevel logistic mixed model

Objectives: The Bluetongue Virus is one of the most studied ruminant diseases, affecting particularly sheep and goats. This study aims to identify, for the first time, the specific risk factors influencing the disease development in Sardinia, using multilevel logistic regression model, in order to give a contribution to the sanitary programs and favour the early detection.   Methods: The data of the present retrospective study, collected from informatics systems of Istituto Zooprofilattico della Sardegna, are referred to all 15,780 Sardinian sheep farms observed for 3 years (2012-2014). The outcome of interest was dichotomous and defined the development of Bluetongue outbreak, after serological test or clinical signs. The effect of several region-specific prognostic factors on disease spread was investigated. Results: The final model indicated that Bluetongue development was significantly associated with an increase in number of animals (P < 0.0001), number of cattle around farm (P  < 0.0001), water surface area (P =0.002), and amount of rainfall in the previous days (P < 0.0001). Furthermore, the altitude over 450 MASL (P < 0.0001), the vaccination prophylaxis (P < 0.0001) and the previous outbreak event (P < 0.0001) had a protective effect against the outcome. Conclusion: The results of this study indicated that number of animals and the amount of rainfall were the most important risk factors that affected the Bluetongue development, while the vaccination prophylaxis was found to be an effective measure in decelerating the disease spread.&nbsp

Clinical findings in sheep farms affected by recurrent bacterial mastitis

This study was aimed to investigate the relationships existing between clinical findings and bacterial entities isolated from milk of dairy sheep affected by mastitis. The influence of other parameters on the clinical picture, such as age, nutritional state, breeding conditions, and milking techniques, was also evaluated. All sheep belonged to flocks suffering from serious and repeated outbreaks of infectious mastitis. A total of 2198 Sarda dairy sheep were subjected to a detailed clinical examination, and at least one clinical sign of mastitis was detected in 1666 sheep (75%). Bacteriological examination of milk samples collected from all animals produced 1093 positive results (49.7%). Of bacterial species identified, three accounted for 55.3% of all isolates: Streptococcus uberis (25.6% of positives and 12.7% of total), Staphylococcus epidermidis (16.2% of positives and 8% of total), and Staphylococcus aureus (13.5% of positives and 6.7% of total). Upon investigation of correlations existing among clinical signs and bacterial species responsible for the outbreak, S. uberis showed a statistically significant correlation with serous appearance of milk, presence of clots in secretions, and reactivity of supramammary lymph nodes (p < 0.05); S. epidermidis showed a statistically significant correlation with presence of pustules and ulcers (p < 0.05); and S. aureus showed a statistically significant correlation with clinical signs of chronic mastitis: nodules, abscesses, and atrophy (p < 0.05%). Manual milking techniques were more associated to udder infections than mechanical milking. However, an interesting correlation emerged between presence of S. uberis and mechanical milking with small portable devices. In conclusion, this study revealed interesting and unprecedented correlations among clinical signs, bacterial species isolated from infected milk, and farm management techniques. The results reported here emphasize the primary role played by clinical practice in managing infectious ovine mastitis outbreaks, and strengthen its relevance for recovery of affected flocks

COVID-19 Trend Estimation in the Elderly Italian Region of Sardinia

December 2019 saw a novel coronavirus (COVID-19) from China quickly spread globally. Currently, COVID-19, defined as the new pandemic by the World Health Organization (WHO), has reached over 750,000 confirmed cases worldwide. The virus began to spread in Italy from the 22nd February, and the number of related cases is still increasing. Furthermore, given that a relevant proportion of infected people need hospitalization in Intensive Care Units, this may be a crucial issue for National Healthcare System's capacity. WHO underlines the importance of specific disease regional estimates. Because of this, Italy aimed to put in place proportioned and controlled measures, and to guarantee adequate funding to both increase the number of ICU beds and increase production of personal protective equipment. Our aim is to investigate the current COVID-19 epidemiological context in Sardinia region (Italy) and to estimate the transmission parameters using a stochastic model to establish the number of infected, recovered, and deceased people expected. Based on available data from official Italian and regional sources, we describe the distribution of infected cases during the period between 2nd and 15th March 2020. To better reflect the actual spread of COVID-19 in Sardinia based on data from 15th March (first Sardinian declared outbreak), two Susceptible-Infectious-Recovered-Dead (SIRD) models have been developed, describing the best and worst scenarios. We believe that our findings represent a valid contribution to better understand the epidemiological context of COVID-19 in Sardinia. Our analysis can help health authorities and policymakers to address the right interventions to deal with the rapidly expanding health emergency

Estimation of R0 for the Spread of the First ASF Epidemic in Italy from Fresh Carcasses

After fifty years of spread in the European continent, the African swine fever (ASF) virus was detected for the first time in the north of Italy (Piedmont) in a wild boar carcass in December, 2021. During the first six months of the epidemic, the central role of wild boars in disease transmission was confirmed by more than 200 outbreaks, which occurred in two different areas declared as infected. The virus entered a domestic pig farm in the second temporal cluster identified in the center of the country (Lazio). Understanding ASF dynamics in wild boars is a prerequisite for preventing the spread, and for designing and applying effective surveillance and control plans. The aim of this work was to describe and evaluate the data collected during the first six months of the ASF epidemic in Italy, and to estimate the basic reproduction number (R0) in order to quantify the extent of disease spread. The R0 estimates were significantly different for the two spatio-temporal clusters of ASF in Italy, and they identified the two infected areas based on the time necessary for the number of cases to double (td) and on an exponential decay model. These results (R0 = 1.41 in Piedmont and 1.66 in Lazio) provide quantitative knowledge on the epidemiology of ASF in Italy. These parameters could represent a fundamental tool for modeling country-specific ASF transmission and for monitoring both the spread and sampling effort needed to detect the disease early

Mathematical Approach to Estimating the Main Epidemiological Parameters of African Swine Fever in Wild Boar

African swine fever (ASF) severely threatens the swine industry worldwide, given its spread and the absence of an available licensed vaccine, and has caused severe economic losses. Its persistence in wild boar (WB), longer than in domestic pig farms, and the knowledge gaps in ASF epidemiology hinder ASF virus (ASFV) eradication. Even in areas where disease is effectively controlled and ASFV is no longer detected, declaring eradication is difficult as seropositive WBs may still be detected. The aim of this work was to estimate the main ASF epidemiological parameters specific for the north of Sardinia, Italy. The estimated basic (R0) and effective (Re) reproduction numbers demonstrate that the ASF epidemic is declining and under control with an R0 of 1.139 (95% confidence interval (CI) = 1.123–1.153) and Re of 0.802 (95% CI = 0.612–0.992). In the last phases of an epidemic, these estimates are crucial tools for identifying the intensity of interventions required to definitively eradicate the disease. This approach is useful to understand if and when the detection of residual seropositive WB is no longer associated with any further ASFV circulation

Webinar - Mecanismos de Legislación y experiencias en marcos regulatorios en la preparación para la prevención y respuesta a las enfermedades transfronterizas (Parte 2)

Participantes: Carmen Bullón, Oficial Jurista de la FAO Ericka Calderón, moderadora, Francesco Feliziani, Veterinario. Sandro Rolesu, especialista en peste porcina africana. Dawn Hunter, Veterinaria Federal del departamento de Agricultura de Estados Unidos.Temas a tratar: Importancia de la legislación de sanidad animal, elementos para la elaboración de una norma PPA, Actas de Protección de Salud Animal, entre otros

Correction: Socio-economic factors as indicators for various animal diseases in Sardinia.

[This corrects the article DOI: 10.1371/journal.pone.0217367.]

Socio-economic factors as indicators for various animal diseases in Sardinia.

The need to consider the role of social factors in the efficacy of farm management and, consequently, in the onset and persistence of diseases typical to animal farms is increasingly being realized increasingly worldwide. Many risk analysis studies have been conducted to assess the role of various factors in the development of animal diseases; however, very few have accounted for the role of social factors. The aim of this work was to bridge this gap, with the main hypothesis that different socio-economic factors could be valid indicators for the occurrence of different animal diseases. A socio-economic analysis was performed using demographic characteristics of the farmers and data from 44 social indicators released by the Italian Statistician National Institute of Statistics (ISTAT) database. African swine fever (ASF) in wild boars (WB) and domestic pigs and other endemic animal diseases and zoonoses in Sardinia were considered, such as cistic echinococcosis (CE), contagious agalactia (CA), trichinellosis, West Nile disease (WND), and bluetongue (BT). Seven different negative binomial regression models were fitted using the number of cases between 2011-2017. Three indicators-cultural demand, employment rate, and legality-showed a statistically significant association with risk for all the diseases considered, but with varying effects. Some indicators, such as the age and sex of the farmer, material deprivation index, number of farms and animals, micro-criminality index, and rate of reported thefts were common to ASF, CA, trichinellosis, and CE cases. Others such as the forest surface and the energy produced from renewable sources were common to BT, WND, and ASF in WB. Tourism in seasons other than summer was a valid predictor of ASF and trichinellosis, while out-of-region hospital use had a statistically significant role in CE risk identification. These results may help understand the social context in which these diseases may occur and thus guide the design and implementation of additional risk management measures that go beyond well-known veterinary measures