Guido Maria Grasso

Occurrence of Vibrio and other pathogenic bacteria in Mytilus galloprovincialis (mussels) harvested from Adriatic Sea, Italy

Sixty-two samples of Mytilus galloprovincialis (mussels) harvested from approved shellfish waters in the Adriatic Sea were examined for the presence of Vibrio, Salmonella, Campylobacter, and verocytotoxin producing Escherichia coli. Vibrio spp. were isolated from 48.4% of samples; the species most frequently found were V. alginolyticus (32.2%) and V. vulnificus (17.7%), followed by V. cincinnatiensis (3.2%), V. parahaemolyticus (1.6%), V. fluvialis (1.6%) and V. cholerae non-O1 (1.6%). V. parahaemolyticus resulted negative to Kanagawa-phenomenon and to PCR amplification of tdh gene. V. cholerae resulted negative to PCR amplification of sto gene. No Salmonella, Campylobacter, or E. coli verocytotoxin-producing strains were isolated. The results of this study suggest the potential risk of ingesting raw or undercooked mussels due to the frequent presence of potentially pathogenic Vibrio species.

Prevalence of Salmonellae, Listeriae, and Yersiniae in the Slaughterhouse Environment and on Work Surfaces, Equipment, and Workers

In 1995 and 1996 a nine-month study was carried out in 11 pig abattoirs located in the Molise region (Italy) to evaluate the degree of contamination of- the slaughterhouse environment, work surfaces, equipment, and personnel by Salmonella spp., Listeria spp., and Yersinia spp. A total of 219 samples were taken over three replications including slaughtering floor and wall, hooks, work-tables, chopping blocks, knives, cleavers, dehairing devices, hands of personnel, clothing, hand-wash basins, and cold room handles, floor, wall, and hooks. Overall, six abattoirs (54.5%) had one or more positive sites, while only 14 of the 219 sites (6.4%) tested were positive for any of considered microorganisms. Salmonella spp. were isolated from 1 of 9 cleavers (11.1 %), 1 of 16 worktables (6.25%), and 1 of 18 slaughtering floors (5.6%). Yersinia enterocolitica was found on 3 slaughtering floors (16.7%) and on 2 worktables (12.5%). Yersinia kristensenii was detected on 2 slaughtering floor swabs (11.1 %). Listeria monocytogenes was isolated from 2 of 20 cold room floor swabs (13.3%) and from 1 of 14 hand-wash basins (7.1%). Other species of Listeria were detected on slaughtering wall and floor swabs and on chopping blocks. Our study indicates that slaughtering floors, cold room floors, and worktables are important sites in abattoirs that may possibly harbor pathogens like Salmonella spp., Yersinia enterocolitica , and Listeria monocytogenes , and that cleaning and sanitizing of the slaughterhouse environment and equipment need a greater emphasis.

Prevalence of Helicobacter-like organisms in porcine gastric mucosa: A study of swine slaughtered in Italy

Recent reports described some cases of gastritis in man caused by an uncultured gram-negative spiral bacterium morphologically identical to organisms observed in the stomachs of mammalians (e.g. cats, dogs, pigs). The aim of the present study is to confirm the presence of these bacteria in Italian swine. Tightly spiralled organisms (Gastrospirillum suis) were found in the stomach of eight (9.4%) out of 85 pigs examined. The bacteria were always associated with macroscopic lesions indicative of gastritis. Attempts to culture H. pylori or Helicobacter-like organisms were unsuccessful. The possibility that Gastrospirillum may be a zoonotic pathogen, with transmission occurring from pigs to humans, is discussed.

Immunomagnetic separation and conventional culture procedure for detection of naturally occurring Salmonella in raw pork sausages and chicken meat

The aim of the study was to compare immunomagnetic separation (IMS) and conventional selective enrichment procedures using selenite cystine broth (SC) and Rappaport–Vassiliadis broth (RV) in 137 naturally contaminated food samples (69 raw pork sausages and 68 chicken meat). The utilization of SC or IMS appeared to be the most appropriate enrichment procedure: 15 out of 18 Salmonella‐positive samples (83·3%) were detected by SC and 12 (66·7%) by IMS; RV yielded only seven positive isolations (38·9%). However, RV yielded the highest count of Salmonella colonies per plate and the lowest interference by competing organisms. IMS could become a reliable alternative to standard enrichment procedures and a combined IMS and selective enrichment broth could increase the chance of Salmonella recovery.

Prevalence and biomolecular characterization of Campylobacter spp. isolated from retail meat.

We estimated the prevalence of Campylobacter spp. in retail meat (n = 352 samples; 104 chicken, 106 pork, and 142 beef) collected in Campobasso, Italy, comparing two microbiological methods. All the isolates were characterized by biomolecular techniques for epidemiological purposes. Campylobacter isolation was performed by selective culture and membrane filtration methods. Phenotypic and genotypic methods for genus and species identification were evaluated together with antimicrobial resistance and plasmid profiling. Sixty-nine (86.2%) samples were positive by selective culture, 49 (61.2%) by membrane filtration, and 38 (47.5%) by both methods. Only 74 of 80 strains were confirmed as Campylobacter spp. by PCR, and two Campylobacter coli were identified as Campylobacter jejuni. Chicken meat was more frequently contaminated than other meats. Selective culture was more sensitive than membrane filtration (85 versus 66%), and specificity of the methods was 98 and 100%, respectively. Among Campylobacter isolates from chicken meat, 86.5% were multidrug resistant. Resistance to ciprofloxacin (51.3%) and enrofloxacin (52.7%) was lower than to nalidixic acid (71.6%). C. coli strains showed the highest cross-resistance for quinolones (82.6%) and fluoroquinolones (60.9%) as well as a high resistance to tetracycline. Plasmids were isolated from six C. coli and two C. jejuni isolates, but no association was detected between antimicrobial resistance and plasmid DNA carriage. Selective culture is considered as the optimal method for Campylobacter isolation, although it was unable to detect all contaminated samples. Membrane filtration provided more specific results but with low sensitivity. A combination of both techniques may offer better results.

Evaluation of immunomagnetic separation and plating media for recovery of Salmonella from meat.

Immunomagnetic separation (IMS) was compared with selective enrichment in selenite cystine (SC) broth for isolation of Salmonella from 86 artificially contaminated ground beef samples. Both Rambach agar (RA) and Hektoen enteric (HE) agar were used as selective plating media. The highest count of Salmonella colonies per plate was obtained after enrichment in SC broth and plating on RA (mean value: 111.1+/-58.1 CFU per plate); the lowest count was obtained after IMS and plating on HE agar (mean value: 65.4+/-36.6 CFU per plate). Salmonella in preenrichment was concentrated 1.7-fold by IMS and represented 31% of the microbial population captured by the beads, but nonspecific binding was high. As a result of the large numbers of competing bacteria, isolations on both RA and HE agar following IMS were quite difficult (mean value for Salmonella colonies: 79.9+/-42.7 CFU per plate; mean value for non-Salmonella colonies: 144.1+/-75.7 CFU per plate; ratio of Salmonella to non-Salmonella colonies: 0.8). This study indicates that SC broth is superior to IMS in the isolation of Salmonella from raw ground meat.

Prevalence and genotype identification of human papillomavirus in women undergoing voluntary cervical cancer screening in Molise, Central Italy

We examined the prevalence of HR- and LR-HPV by Linear Array genotyping test in 299 women aged 18-63 years who consecutively visited Molise Region main hospitals for routine Pap smear between February and August 2008. Ninety women were positive for any HPV (30.1%), and 66 for any HR-HPV (22.1%). The most prevalent HR-HPV types were HPV 16 (22.2% of all women with HPV infection), HPV 53 (14.4%), and HPV 66 (14.4%). HPV infections increased from 15.8% in the 18-20 years group to 50.0% in the 21-23 years group and then decreased to 9.1% in those aged 50 years or more (p=0.008). Multiple HPV infections were observed in 15.7% of the study sample (52.2% of all HPV positive). There is a significantly higher prevalence of multiple infections in 18-32 years group women (24.5%) compared with females aged 33 years or more (6.8%) (p<0.005). Current smokers were at increased risk of HPV infection (44.2% of HPV infections compared with 23.5% in never smokers, and 25.3% of multiple HPV infections compared with 11.3%; p=0.001). HR-HPV infections were higher in women never been pregnant (27.1% compared with 7.7%; p=0.001). Oral contraceptive use was completely unrelated to infection. Among the 122 women who had both cytological examination and HPV results, multiple HR-HPV types were found in 36.8% of those with abnormal cervical findings, and in 13.6% of those with normal cervical findings (p=0.05). The results of the present investigation provide further evidence for the notion that cervical HPV infection is more widespread than previously suggested.

Type-specific persistence and associated risk factors of human papillomavirus infections in women living in central Italy

OBJECTIVE We examined persistence and clearance of human papillomavirus (HPV) infections and risk factors associated with persistence in 79 women based on the results of two sequential tests performed over 12-24 months. STUDY DESIGN Between February 2008 and August 2009, 398 women aged 18-63 years were examined for presence of cervical HPV infection by cervical scrape specimen and PCR. Detection was performed using Linear Array (LA) HPV Genotyping Test. All women were interviewed, and a short questionnaire was administered to collect information on socio-demographic characteristics, sexual and reproductive history, smoking habits, oral contraceptive use, history of sexually transmitted diseases, and Chlamydia trachomatis or Mycoplasma spp. infections. Pearsons χ² test was used to verify the association between all independent variables with the response variable. RESULTS Initially, high risk-HPV (HR-HPV) and low risk-HPV (LR-HPV) infection was detected in 69.6% and 30.4% of the women, respectively, whilst multiple infections occurred in 53.2%. HPV 16 was the most common (20.2%) high-risk type, followed by 52, 31 and 53. At follow-up, HR-HPV infection was detected in 50.6% of the women; among these, 67.5% had persistent infection, while 12.5% acquired other high-risk types, and 20.0% of those positive for LR-HPV at entry had a new HR-HPV infection. Multiple infections were detected in 38.0% of the women. HPV 16 and 31 were the most frequent types, followed by HPV 73. Type-specific HR-HPV persistence was found in 49.1% of women. HPV 31, 39 and 73 were the most frequently persistent types, whilst HPV 16 was the least persistent. No significant age difference between women with persistence or clearance was found. The highest HR-HPV persistence occurred in the 22-27 years old group, whereas clearance increased in women aged 28-33 years. No significant association between persistent HR-HPV infection and oral contraceptive use, smoking habits and history of sexually transmitted disease was detected both at entry and follow-up study. The association between C. trachomatis or Mycoplasma spp. and HPV persistence could not be investigated because of the low detection rate of these microorganisms. CONCLUSIONS The persistence of HR-HPV infection level was similar to that reported elsewhere, and HPV 31, 39 and 73 showed the highest likelihood of persistence, partially in agreement with other studies. The clinical relevance of the low persistence of HPV 16 and other HR-HPV is unknown. Persistent HR-HPV infection in women aged 22-27 years was in agreement with other authors. To the best of our knowledge, this is the first report on persistence of HR-HPV infections in Italy in a general population, although we examined a small sample in a short follow-up time.

Routine Preoperative Investigation: Results of a Multicenter Survey in Italy

We conducted a study to acquire information on the current behavior of a sample of Italian surgeons and anesthesiologists about prescribing, interpreting, and using routine preoperative investigations. Consultants in surgery and anesthesiology in 60 hospitals in northern, central, and southern Italy were interviewed. Prescription of these procedures by doctors were driven more by personal experience than by updated scientific knowledge. This practice often led to ineffective and inefficient clinical practice, with healthy patients undergoing useless, time-consuming, costly, and sometimes harmful procedures.

Prevalence of antibodies against enterically transmitted viral hepatitis (HAV and HEV) among adolescents in an inland territory of central Italy

A study on the seroprevalence of HAV and HEV infections among adolescents in an inland territory of central Italy (Molise region) was carried out. The prevalence of antibodies was respectively 3.3% and 0.4%. The results indicate that (1) anti-HAV prevalence in children is low but HAV infection is always present, and (2) HEV infection could be endemic and not necessarily imported.