Seroprevalence and phylogenetic characterization of hepatitis E virus in pig farms in Southern Italy

Hepatitis E virus (HEV) infection is an emerging public health problem in industrialized countries. The infection is associated with waterborne epidemics and transmitted via faecal-oral route. Zoonotic cases of HEV in humans have increased in Europe, and HEV genotype 3 (HEV-3) is the most frequent among humans and animals. Nevertheless, HEV surveillance in the Italian pig farming industry is patchy. Here, HEV prevalence in pig farms located in the Calabria region in Southern Italy was investigated. A total of 692 serum samples were collected from 26 farms and tested for anti-HEV IgG antibody detection. The percentage of HEV-seropositive pigs was 56.8 %. Small farm size, farrow-to-finishing production, and infrequent cleaning procedures were associated with higher HEV seroprevalence. In 12 of the HEV-seropositive farms, 67 faecal samples were collected and 10 of these (10.6 %) tested positive for HEV RNA. Seven of 10 viral RNA sequences were genotyped for phylogenetic analysis, five of which belonged to subtype HEV-3f and two to subtype HEV-3e. The high HEV seroprevalence and the circulation of HEV-3 strains among domestic pigs in the Calabria region pose a risk for the zoonotic transmission of HEV from pigs to occupational exposed workers.

Presence of Mycobacterium bovis in slaughterhouses and risks for workers

An investigation was carried out to detect the presence of Mycobacterium bovis in slaughterhouses where intradermal tuberculin test positive cattle were slaughtered, and to evaluate the risk of contamination by M. bovis among exposed slaughterhouse workers. Swabs were taken from the carcasses of slaughtered animals showing autoptic signs of non-generalized forms of tuberculosis, thus authorized for free consumption. Swabs were also taken from the hands and clothes of the staff employed in the butchery production line. Environmental samplings were conducted on the slaughterhouse air using filters and air aspiration devices, and on water used to wash the carcasses after slaughter. Samples from the carcasses of healthy animals were also taken on a following slaughtering session. The swabs were analysed by means of Polymerase Chain Reaction for the detection of mycobacteria. M. bovis was detected on meats, on the hands of one worker, and in the washing water. The results obtained from this study confirm that workers are highly exposed to infection by zoonotic tuberculosis, and that cleaning procedures were ineffective in our setting.

Unidirectional animal-to-human transmission of methicillin-resistant Staphylococcus aureus ST398 in pig farming; evidence from a surveillance study in southern Italy

Background

Livestock-associated methicillin-resistant Staphylococcus aureus (MRSA) belonging to clonal complex 398 is recognized as an occupational hazard for workers employed in intensive animal husbandry, especially in the swine-breeding chain. In this study, we compared the prevalence and epidemiological type of MRSA isolates from swine and farm workers in a large area of southern Italy.

Methods

Between January and March 2018, 88 workers from 32 farms where we had previously performed a survey for MRSA colonization of farmed pigs, were sampled by nasal swabbing. A follow-up investigation was conducted on seven workers 1 year after primary screening. MRSA isolates were characterized by MLST, spa and SCCmec typing, and tested for susceptibility to 15 antimicrobials. Epidemiological correlations between human and swine MRSA isolates were supported by Rep-MP3 and RAPD PCR fingerprinting, and whole-genome sequencing.

Results

The overall colonization rate of MRSA in swine farm workers was 21.6%, being significantly higher in intensive farms and in workers with direct animal contact. All human MRSA isolates were multi-drug resistant, belonged to the ST398 livestock clade, and did not carry Panton-Valentine leukocidin and enterotoxin genes. Notably, 94.1% of human MRSA isolates belonged to the same epidemiological type as swine MRSA isolates from the corresponding farm. Persistent MRSA carriage was documented in some workers 1 year after primary sampling.

Conclusions

We report a high prevalence of MRSA among swine farm workers, with higher colonization rates associated with intensive breeding and animal exposure. Our findings suggest unidirectional animal-to-human transmission of LA-MRSA and denote the high zoonotic transmissibility of the ST398 livestock clade.

Prevalence, molecular epidemiology, and antimicrobial resistance of methicillin-resistant Staphylococcus aureus from swine in southern Italy

Background

Colonization by livestock-associated MRSA (LA-MRSA) has increasingly been reported in the swine population worldwide. The aim of this study was to assess the prevalence of MRSA nasal carriage in healthy pigs, including the black (Calabrese) breed, from farms in the Calabria Region (Southern Italy). Between January and March 2018, a total of 475 healthy pigs reared in 32 farms were sampled by nasal swabbing. MRSA isolates were characterized by spa, MLST and SCCmec typing, and susceptibility testing to 17 antimicrobials.

Results

22 of 32 (66.8%) pig farms resulted positive for MRSA. The prevalence of MRSA was 46.1% (219 MRSA culture-positive out of 475 samples). MRSA colonization was significantly higher in intensive farms and in pigs with a recent or ongoing antimicrobial treatment. All 219 MRSA isolates were assigned to ST398. The most common spa types were t011 (37.0%), t034 (22.4%) and t899 (15.1%). A novel spa type (t18290) was detected in one isolate. An insertion of IS256 in the ST398-specific A07 fragment of the SAPIG2195 gene was detected in 10 out of 81 t011 isolates. Nearly all isolates carried the SCCmec type V element, except 11 isolates that carried the SCCmec type IVc. None of the isolates was positive for the Panton-Valentine leukocidin. All isolates were resistant to tetracycline. High resistance rates were also found for clindamycin (93.1%), trimethoprim/sulfamethoxazole (68.4%), fluoroquinolones (47.9–65.3%) and erythromycin (46.1%). None of the isolates was resistant to vancomycin and fusidic acid. Overall, a multidrug resistant phenotype was observed in 88.6% of isolates.

Conclusions

We report a high prevalence of MRSA among healthy swine in Southern Italy farms, with higher isolation frequency associated with intensive farming. The epidemiological types identified in our study reflect those reported in other European countries. Our findings underscore the importance of monitoring the evolution of LA-MRSA in pig farms in order to implement control measures and reduce the risk of spread in the animal population.

Electronic supplementary material

The online version of this article (10.1186/s12866-019-1422-x) contains supplementary material, which is available to authorized users.

[The importance of the airborne microorganisms evaluation in the operating rooms: the biological risk for health care workers]

The operating room is a complex environment, traditionally considered at high infectious risk, for both the patients and the health care workers, they can contract diseases, because of the exposure for relatively long times to various dangerous chemical, physical and biological factors. The biological contamination in the operating rooms is mostly imputable to airborne and bloodborne microorganisms, whose primary source represent the staff: patients and operating team, while either secondary sources are the contaminate air introduced from the VCCC system and the use of the infect instruments. About 10% of the hospital infections are determined by airborne bacteria and a variable fraction of these, not only in immunocompromised patients but also in healthy people, may cause the respirators pathologies. The aim of this paper was to estimate the microbial contamination, in 20 hospitals located in three regions of the South Italy, for a total 81 operating rooms. The results show that 17 of the 20 operating units and 45 out of 81 operating rooms examined are contaminated. Periodic inspections should be carried out in order to control and lower the biological risk for both the patients and the health care workers.

[The d.p.r. 37/97 and the thermal comfort of the surgeons according to the new version of UNI EN ISO 7730]

The Italian law, through a specific government decree (d.p.r. 37/97), recommends the minimal technological, structural and organising requirements that surgery rooms of public hospitals must assure. Nevertheless, thermal comfort is usually evaluated by the indices PMV and PPD (Fanger's indices). Microclimatic data, acquired inside 80 surgery rooms over 20 public hospitals located in South of Italy, have been reviewed taking into account the new version of the international standard UNI EN ISO 7730. This version enables to classify the workers in three categories, A, B and C each one related to a different value of the acceptable number of dissatisfied people PPD. Considering the particular task which surgeons and nurses are involved in, a percentage of dissatisfied < 6% appears more realistic and conservative respect to the 10% prescribed in the old version of the standard. So the calculations show that, in this case, less than 17% of the staff would considered the thermal conditions as comfortable. Furthermore, the range of the microclimatic parameters, as established by the low, is not sufficient to assure thermal comfort using the PMV or PPD.