In vitro phenotypic characterisation of two genotype I African swine fever viruses with genomic deletion isolated from Sardinian wild boars

African swine fever virus (ASFV) causes a devastating disease affecting domestic and wild pigs. ASF was first introduced in Sardinia in 1978 and until 2019 only genotype I isolates were identified. A remarkable genetic stability of Sardinian ASFV isolates was described, nevertheless in 2019 two wild boar isolates with a sustained genomic deletion (4342 base pairs) were identified (7303WB/19, 7212WB/19). In this study, we therefore performed in vitro experiments with monocyte-derived macrophages (moMФ) to unravel the phenotypic characteristics of these deleted viruses. Both 7303WB/19 and 7212WB/19 presented a lower growth kinetic in moMФ compared to virulent Sardinian 26544/OG10, using either a high (1) or a low (0.01) multiplicity of infection (MOI). In addition, flow cytometric analysis showed that both 7303WB/19 and 7212WB/19 presented lower intracellular levels of both early and late ASFV proteins. We subsequently investigated whether deleted virus variants were previously circulating in wild boars in Sardinia. In the four years preceding the last genotype I isolation (February 2015–January 2019), other eight wild boar isolates were collected, all belonging to p72 genotype I, B602L subgroup X, but none of them presented a sustained genomic deletion. Overall, we observed the deleted virus isolates in Sardinia only in 2019, at the end of a strong eradication campaign, and our data suggest that it might possess an attenuated phenotype in vivo. A better understanding of ASFV evolution in endemic territories might contribute to development of effective control measures against ASF

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

Changes in Estimating the Wild Boar Carcasses Sampling Effort: Applying the EFSA ASF Exit Strategy by Means of the WBC-Counter Tool

African swine fever (ASF) is a devastating disease, resulting in the high mortality of domestic and wild pigs, spreading quickly around the world. Ensuring the prevention and early detection of the disease is even more crucial given the absence of licensed vaccines. As suggested by the European Commission, those countries which intend to provide evidence of freedom need to speed up passive surveillance of their wild boar populations. If this kind of surveillance is well-regulated in domestic pig farms, the country-specific activities to be put in place for wild populations need to be set based on wild boar density, hunting bags, the environment, and financial resources. Following the indications of the official EFSA opinion 2021, a practical interpretation of the strategy was implemented based on the failure probabilities of wrongly declaring the freedom of an area even if the disease is still present but undetected. This work aimed at providing a valid, applicative example of an exit strategy based on two different approaches: the first uses the wild boar density to estimate the number of carcasses need to complete the exit strategy, while the second estimates it from the number of wild boar hunted and tested. A practical free access tool, named WBC-Counter, was developed to automatically calculate the number of needed carcasses. The practical example was developed using the ASF data from Sardinia (Italian island). Sardinia is ASF endemic from 43 years, but the last ASFV detection dates back to 2019. The island is under consideration for ASF eradication declaration. The subsequent results provide a practical example for other countries in approaching the EFSA exit strategy in the best choices for its on-field application

A Naturally Occurring Microhomology-Mediated Deletion of Three Genes in African Swine Fever Virus Isolated from Two Sardinian Wild Boars

African swine fever virus (ASFV) is the etiological agent of a lethal disease of domestic pigs and wild boars. ASF threatens the pig industry worldwide due to the lack of a licensed vaccine or treatment. The disease has been endemic for more than 40 years in Sardinia (Italy), but an intense campaign pushed it close to eradication; virus circulation was last detected in wild boars in 2019. In this study, we present a genomic analysis of two ASFV strains isolated in Sardinia from two wild boars during the 2019 hunting season. Both isolates presented a deletion of 4342 base pairs near the 5′ end of the genome, encompassing the genes MGF 360-6L, X69R, and MGF 300-1L. The phylogenetic evidence suggests that the deletion recently originated within the Sardinia ecosystem and that it is most likely the result of a non-allelic homologous recombination driven by a microhomology present in most Sardinian ASFV genomes. These results represent a striking example of a genomic feature promoting the rapid evolution of structural variations and plasticity in the ASFV genome. They also raise interesting questions about the functions of the deleted genes and the potential link between the evolutionary timing of the deletion appearance and the eradication campaign

A Deeper Insight into Evolutionary Patterns and Phylogenetic History of ASFV Epidemics in Sardinia (Italy) through Extensive Genomic Sequencing

African swine fever virus (ASFV) is the etiological agent of the devastating disease African swine fever (ASF), for which there is currently no licensed vaccine or treatment available. ASF is defined as one of the most serious animal diseases identified to date, due to its global spread in regions of Africa, Europe and Asia, causing massive economic losses. On the Italian island of Sardinia, the disease has been endemic since 1978, although the last control measures put in place achieved a significant reduction in ASF, and the virus has been absent from circulation since April 2019. Like many large DNA viruses, ASFV mutates at a relatively slow rate. However, the limited availability of whole-genome sequences from spatial-localized outbreaks makes it difficult to explore the small-scale genetic structure of these ASFV outbreaks. It is also unclear if the genetic variability within outbreaks can be captured in a handful of sequences, or if larger sequencing efforts can improve phylogenetic reconstruction and evolutionary or epidemiological inference. The aim of this study was to investigate the phylogenetic patterns of ASFV outbreaks between 1978 and 2018 in Sardinia, in order to characterize the epidemiological dynamics of the viral strains circulating in this Mediterranean island. To reach this goal, 58 new whole genomes of ASFV isolates were obtained, which represents the largest ASFV whole-genome sequencing effort to date. We provided a complete description of the genomic diversity of ASFV in terms of nucleotide mutations and small and large indels among the isolates collected during the outbreaks. The new sequences capture more than twice the genomic and phylogenetic diversity of all the previously published Sardinian sequences. The extra genomic diversity increases the resolution of the phylogenetic reconstruction, enabling us to dissect, for the first time, the genetic substructure of the outbreak. We found multiple ASFV subclusters within the phylogeny of the Sardinian epidemic, some of which coexisted in space and time

A prospective non-randomized controlled, multicenter trial comparing Appendectomy and Conservative Treatment for Patients with Uncomplicated Acute Appendicitis (the ACTUAA study)

Purpose: Acute appendicitis (AA) is among the most common causes of lower abdominal pain and admissions to the emergency department. Over the past 20 years, there has been a renewed interest in the conservative management of uncomplicated AA, and several studies demonstrated that an antibiotic-first strategy is a viable treatment option for uncomplicated AA. The aim of this prospective non-randomized controlled, multicenter trial is to compare antibiotic therapy and emergency appendectomy as treatment for patients with uncomplicated AA confirmed by US and/or CT or MRI scan. Methods: All adult patients in the age range 18 to 65 years with suspected AA, consecutively admitted to the Surgical Department of the 13 participating Italian Hospitals, will be invited to take part in the study. A multicenter prospective collected registry developed by surgeons, radiologists, and pathologists with expertise in the diagnosis and treatment of uncomplicated acute appendicitis represents the best research method to assess the long-term role of antibiotics in the management of the disease. Comparison will be made between surgical and antibiotic-first approaches to uncomplicated AA through the analysis of the primary outcome measure of complication-free treatment success rate based on 1-year follow-up. Quality of life, length of hospital stay, pain evaluation, and time to return to normal activity will be evaluated as secondary outcome measures. Trial registration: Clinicaltrials.gov ID: NCT03080103