Intestinal infection with enterotoxigenic Escherichia coli (ETEC) is an important disease in swine resulting in significant economic losses. Knowledge about the epidemiology, the diagnostic approach and methods of control are of fundamental importance to tackle the disease. The ETEC causing neonatal colibacillosis mostly carry the fimbriae F4 (k88), F5 (k99), F6 (987P) or F41, while the ETEC of post-weaning diarrhoea carry the fimbriae F4 (k88) and F18. These fimbriae adhere to specific receptors on porcine intestinal brush border epithelial cells (enterocytes), starting the process of enteric infection. After this colonization, the bacteria produce one or more enterotoxins inducing diarrhoea, such as the heat stable toxin a (STa), the heat stable toxin b (STb), and the heat labile toxin (LT). A role in the pathogenesis of the disease was demonstrated for these toxins. The diagnosis of enteric colibacillosis is based on the isolation and quantification of the pathogenic E.coli coupled with the demonstration by PCR of the genes encoding for virulence factors (fimbriae and toxins). The diagnostic approach to enteric colibacillosis must consider the differential diagnosis and the potential different causes that can be involved in the outbreak. Among the different methods of control of colibacillosis, the use of antimicrobials is widely practiced and antibiotics are used in two main ways: as prophylactic or metaphylactic treatment to prevent disease and for therapeutic purposes to treat diseased pigs. An accurate diagnosis of enteric colibacillosis needs an appropriate sampling for the isolation and quantification of the ETEC responsible for the outbreak by using semi-quantitative bacteriology. Definitive diagnosis is based on the presence of characteristic lesions and results of bacteriology along with confirmation of appropriate virulence factors to identify the isolated E.coli. It is important to confirm the diagnosis and to perform antimicrobial sensitivity tests because antimicrobial sensitivity varies greatly among E. coli isolates. Growing concern on the increase of antimicrobial resistance force a more rational use of antibiotics and this can be achieved through a correct understanding of the issues related to antibiotic therapy and to the use of antibiotics by both practitioners and farmers.

Post-weaning diarrhoea (PWD), due to Escherichia coli, is an important cause of economic losses to the pig industry primarily as a result of mortality and worsened productive performance. In spite of its relevance, recent data about the prevalence of virulence genes and pathotypes among E. coli isolates recovered from cases of PWD in Europe are scarce. This study investigates the prevalence of fimbrial and toxin genes of E. coli by PCR among 280 farms with PWD across Europe. A total of 873 samples collected within the first 48 h after the onset of PWD (occurring 7–21 days post weaning) were submitted to the laboratory for diagnostic purposes. Isolation and identification of E. coli were performed following standard bacteriological methods and PCR assays for the detection of genes encoding for fimbriae (F4, F5, F6, F18 and F41) and toxins (LT, STa, STb and Stx2e). The prevalence of fimbriae and toxins among E. coli isolates from cases of PWD was: F4 (45.1 %), F18 (33.9 %), F5 (0.6 %), F6 (0.6 %), F41 (0.3 %), STb (59.1 %), STa (38.1 %), LT (31.9 %) and Stx2e (9.7 %). E. coli isolates carrying both fimbrial and toxin genes were detected in 52.5 % of the cases (178 out of 339 isolates), with 94.9 % of them being classified as enterotoxigenic E. coli (ETEC). The most common virotype detected was F4, STb, LT. This study confirms that ETEC is frequently isolated in pig farms with PWD across Europe, with F4- and F18-ETEC variants involved in 36.1 % and 18.2 % of the outbreaks, respectively.

Salmonella is one of the most spread foodborne pathogens worldwide, and Salmonella infections in humans still represent a global health burden. The main source of Salmonella infections in humans is represented by contaminated animal-derived foodstuffs, with pork products being one of the most important players. Salmonella infection in swine is critical not only because it is one of the main causes of economic losses in the pork industry, but also because pigs can be infected by several Salmonella serovars, potentially contaminating the pig meat production chain and thus posing a significant threat to public health globally. As of now, in Europe and in the United States, swine-related Salmonella serovars, e.g., Salmonella Typhimurium and its monophasic variant Salmonella enterica subsp. enterica 1,4,[5],12:i:-, are also frequently associated with human salmonellosis cases. Moreover, multiple outbreaks have been reported in the last few decades which were triggered by the consumption of Salmonella-contaminated pig meat. Throughout the years, changes and evolution across the pork industry may have acted as triggers for new issues and obstacles hindering Salmonella control along the food chain. Gathered evidence reinforces the importance of coordinating control measures and harmonizing monitoring programs for the efficient control of Salmonella in swine. This is necessary in order to manage outbreaks of clinical disease in pigs and also to protect pork consumers by controlling Salmonella subclinical carriage and shedding. This review provides an update on Salmonella infection in pigs, with insights on Salmonella ecology, focusing mainly on Salmonella Choleraesuis, S. Typhimurium, and S. 1,4,[5],12:i:-, and their correlation to human salmonellosis cases. An update on surveillance methods for epidemiological purposes of Salmonella infection in pigs and humans, in a “One Health” approach, will also be reported.

A fatal Encephalomyocarditis virus (EMCV) infection epidemic involving fifteen primates occurred between October 2006 and February 2007 at the Natura Viva Zoo. This large open-field zoo park located near Lake Garda in Northern Italy hosts one thousand animals belonging to one hundred and fifty different species, including various lemur species. This lemur collection is the most relevant and rich in Italy. A second outbreak between September and November 2008 involved three lemurs. In all cases, the clinical signs were sudden deaths generally without any evident symptoms or only with mild unspecific clinical signs. Gross pathologic changes were characterized by myocarditis (diffuse or focal pallor of the myocardium), pulmonary congestion, emphysema, oedema and thoracic fluid. The EMCV was isolated and recognized as the causative agent of both outbreaks. The first outbreak in particular was associated with a rodent plague, confirming that rats are an important risk factor for the occurrence of the EMCV infection.

From January 2007 to December 2011, a total of 106 Haemophilus parasuis strains isolated from pigs were serotyped by agar gel diffusion test (DG). Serovar 4 was the most prevalent (24.5%), followed by serovar 13 (19.8%) and serovar 5 (11.3%). Twenty-nine strains were non-typeable (27.3%). The strains were divided into two groups, depending on whether they were isolated from specific pathological lesions of systemic disease such as polyserositis, arthritis or meningitis (73 cases of 106) or from the lower respiratory tract of pigs suffering from bronchopneumonia (33 cases of 106). Serovars 4 and 13 had a higher prevalence in systemic infection (polyserositis) than in respiratory disease only. Pasteurella multocida (14/106), Streptococcus suis (7/106), Actinobacillus pleuropneumoniae (4/106), Bordetella bronchiseptica (3/106) and Arcanobacterium pyogenes (3/106) were isolated in association with H. parasuis.

Influenza D virus (IDV) has been increasingly reported all over the world. Cattle are considered the major viral reservoir. Based on the hemagglutinin-esterase (HEF) gene, three main genetic and antigenic clusters have been identified: D/OK distributed worldwide, D/660 detected only in the USA and D/Japan in Japan. Up to 2017, all the Italian IDV isolates belonged to the D/OK genetic cluster. From January 2018 to May 2019, we performed virological surveillance for IDV from respiratory outbreaks in 725 bovine farms in Northern Italy by RT-PCR. Seventy-four farms were positive for IDV. A full or partial genome sequence was obtained from 29 samples. Unexpectedly, a phylogenetic analysis of the HEF gene showed the presence of 12 strains belonging to the D/660 cluster, previously unreported in Europe. The earliest D/660 strain was collected in March 2018 from cattle imported from France. Moreover, we detected one viral strain with a reassortant genetic pattern (PB2, PB1, P42, HEF and NP segments in the D/660 cluster, whilst P3 and NS segments in the D/OK cluster). These results confirm the circulation of IDV in the Italian cattle population and highlight the need to monitor the development of the spreading of this influenza virus in order to get more information about the epidemiology and the ecology of IDV viruses.