1,720,970 research outputs found
Epidemiological characterization and phylogenetic analysis of the emerging Salmonella enterica serovar Napoli: the first cause of invasive nontyphoidal salmonellosis in Lombardy, northern Italy
No full textBackground: Salmonella enterica serovar Napoli is a nontyphoidal serotype that is currently emerging in Europe, mainly affecting Switzerland, France and Italy. In the latter, S. Napoli incidence has
increased by 28.2% during the period 2000-2011, most cases occurring in Lombardy region. Furthermore, a recently large outbreak occurred in Milan, Italy, associated to elevated rates of
hospitalization and bacteraemia, has evidenced that S. Napoli infections may become invasive. By considering the elevated invasive rate observed for that recent outbreak and the knowledge gaps, we
aimed to investigate the role of S. Napoli in invasive salmonellosis in Lombardy during the period 2010-2014, and infer the phylogeny of this emerging serotype. Material/methods: Data of human salmonellosis cases in Lombardy during the period 2010-2014 (10,858 records) were obtained from IT-ENTER-NET, a network of diagnostic laboratories. Comparative genomics analysis based on sequence data for 93 core genome loci, as described by den Bakker et al., was performed to define phylogenetic relationships of 14 Salmonella enterica subsp. enterica serotypes, including S. Napoli outbreak strain, and one S. enterica subsp. arizonae strain. Results: S. Napoli incidence in Lombardy continued to increase during the period 2010-2014. Moreover, this serotype was the first cause of invasive nontyphoidal salmonellosis during 2010-2014 (35 invasive cases out of 691, invasive rate of 5.1%). Phylogenetic analysis revealed that S. Napoli belongs to the Typhi subclade of clade A, and the most related serotype was found to be Paratyphi A. Additionally, S. Napoli genome carries the invasive determinant gene cdtB and the pathogenicity island SPI-18. Conclusions: S. Napoli is an emerging public health concern in Italy. Nevertheless, the role of nontyphoidal serotypes in invasive disease is yet poorly studied. A combination of SPI-18 island and cdtB gene was previously reported only in S. Typhi, S. Paratyphi A and clade B serotypes, all of them associated to elevated rates of invasive disease. Thus, to the best of our knowledge, this is the first time that a clade A nontyphoidal serotype presents the same virulence-genes pattern of S. Typhi and S. Paratyphi A. Our work suggests that S. Napoli potential virulence deserves attention and highlights a need to discuss its classification in nontyphoidal group
Prevalence of intestinal parasitic infections and correlation with hemoglobin blood concentration among school-age children in Yagoua, Cameroon (Logone Valley)
Full text linkObjective: In developing countries, parasitic infections result in considerable gastrointestinal morbidity, malnutrition and mortality, especially among children, probably also contributing to anemia through iron deficiency. Distribution is influenced by behavioral, environmental and socioeconomic factors (poverty, poor sanitation/hygienic practices and lack of clean water and safe food). Intervention setting is located in Logone Valley (Cameroon): here foodborne and waterborne diseases are widespread, especially for microbiologically unsafe surface water consumption. Aim of this cross-sectional study is to describe intestinal parasitic infections’ prevalence in school-age children and infection status correlation with hemoglobin concentration, supporting the development of control measures. Methods: The study was conducted in February 2012 in a public school in Yagoua. Children (5 to 8 years old, both male and female) underwent a clinical assessment and filled a nutritional and health questionnaire. Participants were screened for intestinal parasites: stool specimens were examined through macroscopic (consistency) and microscopic evaluation (presence and amount of eggs, cysts and trophozoites) using direct saline and iodine preparation. Additionally, a complete blood count was performed. Data entry and analysis were done using Microsoft Excel and IBM SPSS 20. Results: 175 children were enrolled: 93 (53%) resulted negative while 82 (47%) were infected with one or more parasites. Male and female prevalences were not statistically different (48.7% versus 45.1%). Most widespread parasite was Entamoeba histolytica/dispar (41/175, 23.4%), followed by Giardia lamblia (28/175, 16%), Hymelonepis nana (17/175, 9.7%) and Trichomonas intestinalis (3/175, 1.7%). 93 children (53%) underwent blood tests, with no difference in hemoglobin concentration between infected and non-infected (11.65±1.02 g/dL versus 11.50±0.80 g/dL). Moreover, prevalence of anemic and non-anemic is equal in both groups (cut-off 11.5 g/dL). Conclusions: This was the first study in Logone Valley assessing parasite distribution in school-aged children. A high prevalence (near 50%) was found, with 4% of multiple infections, suggesting that deworming campaigns’ implementation might be a good option for disease control. No association between anemia and infections was demonstrated and literature on this topic is controversial. These findings might help policy makers improving prevention strategies in this area, like safe water use and consumption, hand hygiene campaigns and health education programs
Valutazione della qualità igienica di latte crudo (RTE) in provincia di Milano
No full textNell’ultimo decennio i processi di standardizzazione avviati dalle grandi imprese del sistema agro-alimentare operanti sui mercati globali hanno contribuito ad una omologazione dei gusti e dei consumi ed alla forte riduzione della possibilità per il consumatore di esercitare un controllo diretto sull’origine e sulle modalità di produzione di ciò che acquista e consuma. Si assiste ultimamente al moltiplicarsi di iniziative volte a ricondurre il prodotto al suo luogo di origine ed a ridare visibilità ai produttori. È nell’ambito di questo processo che si inserisce la vendita diretta da parte di allevatori-produttori ai consumatori di latte crudo, cioè di latte che non subisce alcun trattamento termico (pastorizzazione) prima della sua commercializzazione.
Nella Regione Lombardia è stato istituito il “Piano Regione Lombardia per la vendita del latte crudo” che riporta le linee guida per l’esecuzione dei controlli volti a garantire la conformità alla normativa comunitaria nell’ambito della produzione e conferimento del latte crudo per il consumo umano.
L’indagine, svolta presso il laboratorio di riferimento delle Aziende Sanitarie della Provincia di Milano, attivo presso l’Istituto Zooprofilattico della Lombardia e dell’Emilia Romagna, sezione di Milano (IZS-MI) ha riguardato campioni di latte crudo non pastorizzato prodotto in Provincia di Milano e Monza Brianza nel periodo aprile-ottobre 2012 e prelevati in regime di autocontrollo dalle aziende di produzione. Secondo il piano di autocontrollo la qualità igienica è stata determinata sulla base dei seguenti parametri: Enterobacteriaceae, Escherichia coli (indicatore di contaminazione fecale), Staphylococcus aureus (indicatore di igiene di processo) e Streptococcus agalactiae (indicatore di mastite bovina).
In totale, su 383 campioni di latte crudo, di cui 282 provenienti dai tank di stoccaggio di aziende agricole e 101 da erogatori, 70 (18,2%) sono risultati non conformi; di questi, 58 provenivano dai tank e 12 da erogatori. In particolare, il parametro per il quale l’esito sfavorevole è stato osservato con maggiore frequenza (12%) è quello delle Enterobacteriaceae, seguito dalla colimetria (6,8%); più sporadica è risultata la non conformità, S.aureus e S.agalactiae, rispettivamente osservata in soli 11(2,9%) e 2 (0,7%) casi.
Questo tipo di prodotto, come del resto tutti i prodotti di origine animale e vegetale consumati crudi, mantiene per sua propria natura, una intrinseca componente di rischio. Anche con controlli molto frequenti non è infatti possibile escludere, in senso assoluto, l’eventualità di una occasionale o fortuita contaminazione microbica, la cui ricaduta sui consumatori costituisce un rischio di grado diverso in funzione della suscettibilità del soggetto.
Per prevenire le possibili contaminazioni è bene rispettare: le buone pratiche igieniche di lavorazione e di produzione (GHP e GMP) già dalle fasi di mungitura, stoccaggio e trasporto del latte, con particolare attenzione al rispetto della catena del freddo al fine di evitare la produzione di tossine termoresistenti
Epidemiological and molecular characterization of Salmonella enterica serovar Napoli isolated in Northern Italy (2009-2013)
No full textObjectives .One event that has emerged since the beginning of this century has been the increase of cases of human infection due to Salmonella enterica serovar Napoli in Italy. The aims of our study were to describe the spatial and temporal distribution of S. Napoli human infections in Lombardy region between 2009 and 2013, and to assess clonality of the strains isolated from different sources by using Pulsed-Field Gel Electrophoresis (PFGE).
Methods. All S. Napoli cases in Lombardy region reported from two surveillance system in the five years period, were included in our study. The data sources were national mandatory notification system (MAINF) and laboratory-based surveillance system (IT-Enter-net). Therefore, it was possible to realize a database that collects the reported cases by both systems. Moreover, a random sample of isolates (10%) collected by the Regional Reference Laboratory were sub-typed by PFGE according to PulseNet protocol and compared with 19 animal samples isolated by Istituto Zooprofilattico Sperimentale and Istituto Superiore di Sanità. Results. The comparison of the two databases detected a total of 645 observed cases, including 475 isolates detected only by IT-Enter-net system, 44 cases notified only by MAINF system and 126 cases recognized by both surveillance sources. These data revealed that IT-Enter-net network sensitivity was higher than MAINF system (91.5% vs 8.5%), since it is used to detect even the out-patient cases. It was possible to observe an increase in reported cases and a steady state in the following years. During the study period, the highest isolation rates were for infants (0-4 years, 47.9%) and for children (5-14 years, 21.7%). There was no evident differences between males and females. The average annual incidence rate was 1.3/105 inhabitants in Lombardy region, considering the observed cases by both sources. Figure 1 shows the distribution at the province level of the mean incidence rate in the five years period: the highest incidence rate were observed in the provinces of Como, Lecco and Varese. Every year, the largest proportion of S. Napoli isolates was observed between June and October. S. Napoli isolates compared by PFGE exhibited high levels of diversity (twenty-six XBa pulsotypes with a similarity value higher than 80%) between human and animal sources. Conclusion. Salmonella Napoli is relatively uncommon in Europe, while our data reveal that it ranks 3rd in the Lombardy region (17% of Italian population). Concerning possible source of infection or reservoir, the results did not point out any, but our hypothesis is that the environment can act as the main reservoir for S. Napoli, and from there it can spill over to animals and humans. Further studies are needed to increase the knowledge on the ecology and on the main risk factors for human infection
Introduction of integrated surveillance system of listeriosis in northern Italy (2012): molecular subtyping of human and food-environmental Listeria monocytogenes isolates
No full textHuman invasive listeriosis is a relatively rare (0.32 cases per year per 100,000 inhabitants in EU) but life
threatening foodborne disease, with high hospitalization and fatality rates (>90% and 20-30% respectively) in vulnerable populations [1]. The aims of this study were to assess the molecular clustering of L. monocytogenes isolates by using pulsed-field gel electrophoresis (PFGE) and to evaluate phylogenetic correlation of human and food isolates in 2012 in Lombardy, the largest northern Italy region (about 10 million inhabitants), in order to activate an integrated laboratory-based surveillance network and strengthen the surveillance system of human listeriosis cases. This pilot study shows preliminary data in order to identify the main pulsotypes and the foods potentially involved in listeriosis cases in the Lombardy region. The results revealed the need to implement an integrated surveillance system, through the improvement of sampling criteria in foods of the whole area under study and strengthen the surveillance system of human cases
Trend of an emerging Listeria monocytogenes sequence type in Northern Italy
No full textObjective
Invasive listeriosis is a rare, life-threatening foodborne disease. In Lombardy region, Italy, twelve PFGE clusters were identified in the years 2006-2010, among which the major detected was named PFGE Cluster 11-1/2a-ST38/CC101 (Mammina et al., 2013). This cluster deserves special attention, due to its geographic and temporal size.
The aim of this study was to monitor the frequency trend of emerging Listeria monocytogenes Cluster 11-ST38/CC101 in the years (2011-2013) following to the first reporting.
Methods
In Lombardy region, Italy, the national mandatory notification system has been integrated since 2005 with a laboratory-based surveillance network involving voluntary referral of clinical isolates, from Lombardy hospitals to a Regional Reference Laboratory at the University of Milan. All human L. monocytogenes isolates collected by the Regional Reference Laboratory, were serotyped and subtyped by Pulsed-Field Gel Electropheresis (http://www.cdc.gov/pulsenet/pathogens/listeria.html) and Multi-locus Sequence Typing (http://www.pasteur.fr/recherche/genopole/PF8/mlst/primers_Lmono.html) for cluster definition.
Results
In the period under study (2006-2013), 246 human isolates of L. monocytogenes were collected, among which Cluster 11-1/2a-ST38/CC101 included 42 isolates (17.1%). Their identification began in 2006 (n=2) and 2008 (n=2), peaked in 2009 (n=9), 2010 (n=16) and 2011 (n=10), and continued in 2012 (n=1) and 2013 (n=2). Through the entire period, cases were distributed in eight out of eleven provinces of Lombardy with the highest frequency in Bergamo and Milan. Two cases were pregnancy-associated and 40 were non-pregnancy associated. In this latter group, the median age of patients was 67 years (16 Male/24 Female), with 81% of cases being older than 65 years. The main clinical presentation was septicaemia, followed by meningitis and other infections. Treatment with immunosuppressive drugs and neoplasia were the main risk factor (54.1%). The fatality rate of 23 cases with a known survival outcome was 13%.
Conclusion
Our findings revealed a peak of cases prolonged in 2011 and a subsequent return to the initials values in the following years (2012-2013). The trend of the cluster 11-1/2a-ST38 leads us to suppose a possible outbreak, not detected by local health authorities, occurred in the years 2009-2011. Moreover, similar ST38 cases have been reported in France (1997) and in Germany (2011)
Antimicrobial susceptibility of Listeria monocytogenes isolates from human cases in northern Italy, 2008-2010: MIC determination according to EUCAST broth microdilution method
No full textSusceptibility of 96 Listeria monocytogenes human isolates collected in northern Italy between 2008 and 2010, to 15 antimicrobials, was investigated. Minimum inhibitory concentration (MIC) was evaluated by means of the standardized broth microdilution method, according to the European Committee on Antimicrobial Susceptibility Testing (EUCAST) international guidelines. All L. monocytogenes human isolates were susceptible to penicillin G (MIC90≤0·06 μg/ml), meropenem (MIC90≤0·06 μg/ml), and erythromycin (MIC90 = 0·12 μg/ml). Susceptibility to the other tested antimicrobials could not be interpreted due to the lack of breakpoint values although two (2%) isolates were shown to have tetracycline MICs above EUCAST epidemiological cut-off values (ECOFF). Bactericidal activity for amoxicillin, gentamicin, and levofloxacin was generally observed at concentrations 2-4 times higher than MIC values. Though L. monocytogenes human strains, isolated in the north of Italy, appear to be susceptible to most antimicrobial agents used in human therapy, this study provides new data for epidemiological surveillance and clinical breakpoints definition
Methicillin-Resistant Staphylococcus aureus in Raw Milk : Prevalence, SCCmec Typing, Enterotoxin Characterization, and Antimicrobial Resistance Patterns
Full text linkStaphylococcus aureus is a known major cause of foodborne illnesses, and raw milk and dairy products are often contaminated by enterotoxigenic and antimicrobial-resistant S. aureus strains. In the present study, 35 S. aureus strains were isolated from 383 raw milk samples collected from various dairy herds in the province of Milan (northern Italy). The isolates were characterized based on their antimicrobial susceptibility patterns and the presence of genes encoding staphylococcal enterotoxins
(sea, seb, sec, sed, and see). About half (45.7%) of the strains were enterotoxigenic, and 37.1% were resistant to at least one of the antimicrobial drugs tested. Seven (20%) of 35 isolates were identified as methicillin-resistant S. aureus (MRSA), and
SCCmec typing performed with a multiplex PCR assay revealed the presence of gene cassettes IV and V, typical of community acquired MRSA, and I and II, characteristic of health care–associated MRSA. The MRSA strains were evaluated for the presence
of the Panton-Valentine leukocidin gene, but this gene was not found. The results of the present study revealed the presence of toxin-producing S. aureus and MRSA strains in raw milk. MRSA and enterotoxigenic S. aureus in dairy farms are an important risk factor for the spread of staphylococcal infections; therefore, further studies are needed to find strategies for monitoring and controlling the presence of S. aureus, especially MRSA, in dairy products
Listeriosi in Lombardia, 2016: caratteristiche epidemiologiche e molecolari
Full text linkIntroduzione. La listeriosi è una patologia provocata dall’ingestione di alimenti contaminati dal batterio Listeria monocytogenes. È considerata atipica per le sue peculiari caratteristiche di invasività e severità clinica, gravata da una letalità pari al 20-30%. In questa sede, riferiamo le caratteristiche epidemiologiche e molecolari della listeriosi in Lombardia, osservate attraverso il lavoro svolto presso il Laboratorio di Riferimento Regionale (LRR) nel 2016.
Metodi. Nello studio sono stati inclusi i casi rilevati sia dal sistema di notifiche MAINF sia quelli pervenuti presso il LRR tramite invio del ceppo da parte degli ospedali. Su questi ultimi è stata fatta l’analisi molecolare tramite PFGE.
Risultati. Nel 2016 sono stati osservati 66 casi di listeriosi, corrispondenti a un’incidenza regionale di 0.66 casi/100.000 abitanti. Il 9% (6/66) è risultato correlato con la gravidanza. L’analisi molecolare ha mostrato la presenza di cluster (similarità >80%) tra i ceppi coinvolti.
Discussione. I risultati mostrano un andamento della listeriosi simile ai dati europei e, più in generale, con la letteratura.
Il numero dei casi legati alla gravidanza è, però, nettamente inferiore a quello riportato in letteratura: ciò potrebbe essere frutto di una reale minor frequenza dell’infezione nelle gestanti in Lombardia, ma anche di una minor sensibilità diagnostica, spiegando anche l’assenza di casi nelle prime settimane di gestazione. La presenza di cluster indica una correlazione tra i casi dovuta, probabilmente, alla presenza del patogeno nelle filiere alimentari e la sua dispersione per mezzo della commercializzazione su ampia scala temporale/spaziale del prodotto contaminato
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