tst1-positive ST22-MRSA-IVa in healthy Italian preschool children.

A survey was performed in May 2013 to assess methicillin-resistant Staphylococcus aureus (MRSA) nasal colonization in healthy children attending 26 municipal daycare centres in Palermo, Italy. Of the 500 children, ten (2 %) tested positive. Eight MRSA isolates were tst1-positive ST22-MRSA-IVa, spa t223; the other two isolates were identified as ST1-IVa and ST398-V, respectively. tst1-positive ST22-MRSA, spa t223 has been previously identified only in the Middle Eastern area.

Prevalence survey of healthcare-associated infections and antimicrobial use at the University Hospital "Paolo Giaccone", Palermo, Italy.

INTRODUCTION: Healthcare-associated infections (HAIs) and antimicrobial resistance are well known major public health threats. The first goal of our study was to describe the prevalence of HAI, while the second goal was to describe the antibiotic consumption at our University Hospital, "P. Giaccone" in Palermo, Italy. METHODS: A standardized methodology for a combined Point Prevalence Survey (PPS) on healthcare-associated infections (HAIs) and antimicrobial use in European acute care hospital developed by the European Centre for Disease Prevention and Control (ECDC) was piloted across Europe. The teaching Hospital "P. Giaccone" in Palermo, Italy, participated in the study. RESULTS: Out of 328 surveyed patients, 12 (3.6%) had an HAI and 159 (48.5%) were receiving at least one antimicrobial agent. Prevalence results were highest in intensive care units, with 17.6% patients with HAI. Bloodstream infections represented the most common type (50%) of HAI. Surgical prophylaxis was the indication for antimicrobial prescribing in 59 (37.1%) out of 159 patients and exceeded 24 hours in 54 (91.5%) cases. DISCUSSION: The results suggest that in our hospital there was a frequent and inappropriate use of antimicrobials, especially in the setting of surgical prophylaxis.

Ongoing spread of colistin-resistant Klebsiella pneumoniae in different wards of an acute general hospital, Italy, June to December 2011.

We describe polyclonal spread of colistin-resistant Klebsiella pneumoniae in an acute general hospital in Italy. Between June and December 2011, 58 colistin-resistant K. pneumoniae isolates were recovered from 28 patients admitted to different wards, but mainly in the intensive care units. All isolates were tested for drug susceptibility and the presence of beta-lactamase (bla) genes. Clonality was investigated by repetitive extragenic palindromic (rep)-PCR and multilocus sequence typing (MLST). Fifty-two isolates had minimum inhibitory concentrations (MICs) for colistin of 6-128 mg/L, carried bla(KPC3) and were attributed to sequence type ST258. The remaining six isolates were susceptible to carbapenems, exhibited MICs for colistin of 3-32 mg/L, and belonged to two different types, ST15 and ST273. Rep-PCR included all isolates in three clusters, one containing all ST258 KPC-3-producing isolates and two containing ST15 and ST273 isolates.Cross-transmission containment measures and intensification of staff and environmental hygiene could not stop the outbreak. Selective pressure and horizontal transmission probably contributed to emergence and spread of three different strains of colistin-resistant K. pneumoniae in the hospital. Strict implementation of the above measures and a wider awareness of the antimicrobial resistance threat are crucial to preserve the last therapeutic options of the multidrug-resistant Gram-negative infections.

Chemical composition and antibacterial potential of Artemisia arborescens L. essential oil.

This study was undertaken to characterize the essential oil (EO) of Artemisia arborescens growing wild in Sicily. EO, extracted by steam distillation, was examined for its chemical composition and for its capability to inhibit some food-borne pathogen bacteria. A total of 43 compounds (13 monoterpene hydrocarbons, 14 oxygenated monoterpenes, 10 sesquiterpene hydrocarbons, three oxygenated sesquiterpenes and less amount of other three compounds), which account 93.73% of the total oil, were identified by gas chromatography and gas chromatography-mass spectrometry. Oxygenated monoterpenes (57.32%) constituted the main fraction, with ß-thujone as the main compound (45.04%), followed by the sesquiterpene hydrocarbon chamazulene (22.71%). Undiluted EO showed a large inhibition spectrum against strains of Listeria monocytogenes (34 out of 44), whilst it was ineffective against enterobacteria and salmonellas. The minimum inhibition concentration (MIC) was evaluated for the two most sensitive strains (L. monocytogenes 186 and 7BO) at two cellular concentrations (10(6) and 10(7) CFU ml(-1)). The lowest MIC (0.625 µl ml(-1), dilution of oil with acetone) was found for strain L. monocytogenes 186 at 10(6) CFU ml(-1).

A food borne outbreak of Salmonella enterica serotype Brandenburg as a hint to compare human, animal and food isolates identified in the years 2005-2009 in Italy.

INTRODUCTION: There are only a few reported cases of Salmonella enterica serotype Brandenburg foodborne outbreaks in the literature. In Italy Brandenburg is consistently present among the top ten serotypes from human source, but at low prevalences. MATERIALS AND METHODS: Fifty-five S. Brandenburg isolates from human, animal, environmental and food sources, including twelve isolates from a foodborne outbreak, were genotyped by Pulsed-Field Gel Electrophoresis (PFGE). RESULTS AND DISCUSSION: Eight pulsogroups and 19 pulsotypes were detected, with a unique pulsotype being attributed to the outbreak strains. Molecular subtyping can reliably complement the epidemiological investigations. Moreover, mapping molecular types of Salmonella isolates from human and non-human source may greatly contribute to risk assessment, by tracking possible animal sources, so improving cost-effectiveness of the prevention and control strategies.

Epidemiological evaluation by PCR ribotyping of sporadic and outbreak-associated strains of Salmonella enterica serotype Typhimurium.

Salmonella enterica serotype Typhimurium has a very large diffusion worldwide within human and non-human hosts. The simultaneous circulation in the same geographical areas of many bacterial clones requires the use of reliable, reproducible and highly discriminatory typing techniques for epidemiological studies. Molecular biological methods, such as plasmid profile analysis, restriction endonuclease digestion of plasmid and chromosomal DNA and hybridization-based procedures have proven to be useful tools for strain differentiation. More recently, detection of polymorphisms in the intergenic spacer regions of rRNA genes by polymerase chain reaction (PCR ribotyping) has been successfully applied to characterize bacterial strains. In this study, PCR ribotyping was performed on 45 epidemiologically related and unrelated strains of S. enterica serotype Typhimurium isolated in northern and southern Italy during 1992. Isolates were simultaneously characterized by traditional ribotyping. Results suggest that PCR ribotyping is a rapid, easy-to-perform and reproducible typing method able to determine relatedness among isolates of this serotype.

Epidemiology of Salmonella enterica serotype Enteritidis infections in southern Italy during the years 1980-1994.

Increased frequency of identification of Salmonella enterica serotype Enteritidis as a causative agent of sporadic and epidemic cases of infection in humans, along with isolation in many parts of the world of strains belonging in a large proportion to a few phage types, has made phage typing alone inadequate for epidemiological investigations. In southern Italy the epidemic increase in isolation of S. enterica serotype Enteritidis that has been observed since 1990 has been associated in approximately 80% of isolates with phage type 4 (PT-4), in agreement with the epidemiological observations from other European countries. We have applied polymerase chain reaction (PCR) ribotyping in association with phage typing to a sample of non-outbreak strains and to all the outbreak strains sent for identification and typing to the Southern Italy Centre for Enterobacterial Pathogens between 1980 and 1994 from hospital and public health laboratories. This technique identified 15 distinct profiles among the 405 strains examined. Whereas a single profile (PCR ribotype a1) appeared to be closely related to PT-8, and to characterize a high percentage of the strains circulating during the early non-epidemic years (1980-1985), 11 patterns were recognizable within PT-4, and 5 within PT-1. Some of these apparently emerged after 1990. This subdivision enabled attribution of the epidemic circulation of PT-4 to multiple clones of S. enterica serotype Enteritidis.

Molecular analysis of strains of Shigella boydii isolated in northern and southern Italy.

In the years 1981-1988, Shigella boydii played a very limited role in the aetiology of diarrhoeal disease in Italy. However, between September and November, 1985, 19 isolates of serotype 2 were recovered in northern Italy from a dysentery outbreak which occurred in a geriatrics hospital in Abbiategrasso (Milan, Lombardy) and seven were identified in southern Italy during the period January-July, 1986 from apparently unrelated infection cases occurring in Brindisi (Apulia). These isolates were compared by molecular methods to seven strains of S. boydii of serotype 2 isolated since 1981 from the same geographic areas. Plasmid DNA analysis showed a large variety of patterns, whereas hybridization of chromosomal DNA with E. coli rRNA identified only two different profiles, one of which was exclusively found in all isolates from the hospital outbreak. No differences were detected among rDNA patterns of the remaining strains of S. boydii, irrespective of their geographic origin. These findings are consistent with the hypothesis that the infrequent cases of infection from S. boydii of serotype 2 which occurred during the years under study could probably be attributed to two different bacterial clones. Hybridization procedure and detection of hybrids were simplified by replacement of radioactive labelling of rRNA by the use of photobiotin.

Epidemiological analysis of strains of Salmonella enterica serotype Enteritidis from foodborne outbreaks occurring in Italy, 1980-1994.

Polymerase chain reaction (PCR-) ribotyping was performed on 243 strains of Salmonella enterica serotype Enteritidis isolated during the years 1980-1994 from 58 foodborne outbreaks occurring in different regions of Italy. The majority (37) of the outbreaks were attributed to phage type (PT) 4, followed by PT1 (seven outbreaks); the latter was identified in 1993 in Italy in epidemic strains of Enteritidis. In eight cases more than one phage type was recognised from a single event. Nine PCR-ribotypes (PCR-RTs) were detected, with a strong prevalence of PCR-RTs f7 and e5 (23 and 21 outbreaks, respectively). In two instances two distinct PCR-RTs were identified within strains from a single outbreak. All but one of the PT1 outbreaks were caused by PCR-RT f7, whereas PT4 outbreaks could be subdivided into six subsets. Clustering of isolates was consistent with data obtained from epidemiological investigations. PCR-ribotyping proved to be an effective and reliable tool for subtyping isolates of Enteritidis belonging to the most frequent phage types. Nevertheless, in terms of laboratory expertise and lack of inter-laboratory standardisation, this typing technique is best suited for reference laboratories.

Outbreak of Salmonella enteritis bongori 48:z35:- in Sicily.

Salmonella bongori 48:z 35 :- was first isolated from a lizard in Chad in 1966 and was classified as a biochemically atypical strain of the subgenus I of Kauffmann. Successively, some additional strains with different antigenic formulas but similar bioche

Endemic presence of Salmonella enterica serotype Cerro in southern Italy.

Molecular typing of salmonella strains isolated between 1997 and 1999 in southern Italy and carried out by the Southern Italy Centre for Enteric Pathogens, has shown a high frequency of Salmonella enterica serotype Cerro. This serotype is extremely rare i

Clonal circulation of Salmonella enterica serotype Heidelberg in Italy?

Phenotypic and genetic characteristics of 21 strains of Salmonella serotype Heidelberg isolated in the years 1999-2003 from different sources in Italy were studied. Susceptibility patterns, plasmid analysis, and PFGE were used as epidemiological markers. Although non-homogeneous drug resistance patterns and plasmid profiles had been detected, PFGE patterns suggest the hypothesis of a nationwide clonal spread of this serotype associated with poultry.

Detection of Salmonella spp. in food by a rapid PCR-hybridization procedure.

A rapid and sensitive PCR-hybridization procedure for detection of Salmonella serovars in food samples was developed. This method is based on three subsequent steps: (1) extraction of nucleic acids from a 2 ml aliquot of the pre-enrichment medium used for the conventional culture method after 6 h of incubation at 37 degrees C; (2) amplification with primers selected from the sequences of invE and invA genes; (3) Southern blot and hybridization with a biotin labeled oligonucleotide probe. The entire procedure requires 30 h. The PCR-hybridization assay was able to detect as little as 50 fg of purified chromosomal DNA of S. typhimurium and 0.2 cfu g-1 of an artificially contaminated food sample. Of 245 food samples analyzed by culture and PCR-hybridization, 20 were positive by both methods and 16 were positive by PCR-hybridization only. None of the 209 PCR-negative samples tested positive by culture. The sensitivity, specificity, alpha and beta error values of the results of the PCR-hybridization procedure, compared with those of culture, were 100, 92.9, 0 and 7.1%, respectively. These results indicate that a short pre-enrichment and PCR-hybridization could be used as a screening test for the detection of Salmonella in food samples.

A foodborne outbreak of Salmonella enteritidis vehicled by duck and hen eggs in southern Italy.

A foodborne outbreak of Salmonella enteritidis PT4 is described. This microrganism was detected in a home-made dessert, in the duck and hen eggs used for its preparation and in faecal samples of six persons involved in the outbreak. PCR ribotyping revealed that all the strains shared a profile of S. enteritidis never previously identified in southern Italy and quite different from that of the strains simultaneously isolated in the same geographic area. The possible identification of a clonal variant of S. enteritidis PT4 host-adapted to duck is hypothesized.

Dispersal of methicillin resistant Staphylococcus aureus (MRSA) in a burn intensive care unit.

Methicillin resistant Staphylococcus aureus (MRSA) is a pathogen of special concern in intensive care units (ICUs). The burn units are a very susceptible habitat to colonization and infection events by this organism. In this paper isolation of MRSA from a sepsis case and from samples of the care unit air is described, along with simultaneous circulation of two clones of MRSA. Some peculiar epidemiological features of MRSA in burn intensive care wards are confirmed.

[Tuberculin test: proposal for a pre-test risk assessment questionnaire and a standardized evaluation]. / Test alla tubercolina: proposta di scheda di valutazione del rischio e di interpretazione standardizzata.

Relevance of latent infection in the epidemiology of tuberculosis (TB) is expected to increase in many developed countries. Indeed, many demographic, social and public health changes could contribute to the expansion of groups or communities at significantly higher risk than the general population for infection to Mycobacterium tuberculosis or progression from latent to active disease. Tuberculin skin testing (TB), the gold standard for diagnosis of M. tuberculosis infection, is imperfect and prone to false positive and negative results, unless strictly targeted and carefully standardized for reliable performance and interpretation. This paper proposes a pre-test risk assessment questionnaire and standardized criteria for evaluation of TB test according to international guidelines.

Can influenza vaccination coverage among healthcare workers influence the risk of nosocomial influenza-like illness in hospitalized patients?

BACKGROUND: Approximately 20% of healthcare workers are infected with influenza each year, causing nosocomial outbreaks and staff shortages. Despite influenza vaccination of healthcare workers representing the most effective preventive strategy, coverage remains low. AIM: To analyse the risk of nosocomial influenza-like illness (NILI) among patients admitted to an acute care hospital in relation to influenza vaccination coverage among healthcare workers. METHODS: Data collected over seven consecutive influenza seasons (2005-2012) in an Italian acute care hospital were analysed retrospectively. Three different sources of data were used: hospital discharge records; influenza vaccination coverage among healthcare workers; and incidence of ILI in the general population. Clinical modification codes from the International Classification of Diseases, 9(th) Revision were used to define NILI. FINDINGS: Overall, 62,343 hospitalized patients were included in the study, 185 (0.03%) of whom were identified as NILI cases. Over the study period, influenza vaccination coverage among healthcare workers decreased from 13.2% to 3.1% (P < 0.001), whereas the frequency of NILI in hospitalized patients increased from 1.1‰ to 5.7‰ (P < 0.001). A significant inverse association was observed between influenza vaccination coverage among healthcare workers and rate of NILI among patients (adjusted odds ratio 0.97, 95% confidence interval 0.94-0.99). CONCLUSION: Increasing influenza vaccination coverage among healthcare workers could reduce the risk of NILI in patients hospitalized in acute hospitals. This study offers a reliable and cost-saving methodology that could help hospital management to assess and make known the benefits of influenza vaccination among healthcare workers.

Seasonal variations of antimicrobial activity and chemical composition of essential oils extracted from three Citrus limon L. Burm. cultivars.

In order to investigate the seasonal variations of antimicrobial properties and chemical composition of essential oils (EOs), three different cultivars of Citrus limon L. Burm. spp. (Femminello Santa Teresa, Monachello and Femminello Continella) were collected at 6-week intervals, from December 2012 to April 2013, for a total of four harvests. The EOs were extracted from lemon peel by hydro-distillation. The antimicrobial activity, tested by paper disc diffusion method, was evaluated against common food-related pathogenic bacteria (Listeria monocytogenes, Staphylococcus aureus, Salmonella enterica and Enterobacter spp.). EOs were more effective against Gram-positive than Gram-negative bacteria at each collection time, but a strong strain dependence was evidenced. Monachello EOs showed the highest inhibition power. The chemical characterisation of the EOs performed by gas chromatography/mass spectrometry identified from 36 to 42 molecules. The chemical difference registered among samples and seasons may explain the different antimicrobial efficacies recorded.

Successful control of an outbreak of colonization by Klebsiella pneumoniae carbapenemase-producing K. pneumoniae sequence type 258 in a neonatal intensive care unit, Italy.

This article reports an outbreak of colonization by Klebsiella pneumoniae carbapenemase-producing K. pneumoniae (KPC-Kp) sequence type (ST) 258 in a neonatal intensive care unit (NICU) in Palermo, Italy. KPC-Kp ST258 was detected by an active surveillance culture programme. Between 18th September and 14th November 2012, KPC-Kp was isolated from 10 out of 54 neonates admitted in the outbreak period. No cases of infection were recorded. Male sex was associated with colonization, whereas administration of ampicillin- sulbactam plus gentamicin was protective. Infection control interventions interrupted the spread of KPC-Kp without the need to close the NICU to new admissions.

A novel VIM-type metallo-beta-lactamase (VIM-14) in a Pseudomonas aeruginosa clinical isolate from a neonatal intensive care unit.

A Pseudomonas aeruginosa highly resistant to carbapenems was isolated in a neonatal intensive care unit in Palermo, Italy. The strain was found to carry a novel VIM-type enzyme, classified as VIM-14. The novel enzyme differs from VIM-4 in a G31S mutation. VIM-14 was harboured in a class 1 integron with a new organization. The integron carried the genes aac7, blaVIM-14, blaOXA-20 and aac4 in that order.