Paola Vacca

Increased incidence of invasive meningococcal disease of serogroup C / clonal complex 11, Tuscany, Italy, 2015 to 2016.

We report an increase of serogroup C Neisseria meningitidis invasive meningococcal disease in Tuscany. From January 2015 to end February 2016, 43 cases were reported, among which 10 were fatal, compared to two cases caused by serogroup C recorded in 2014 and three in 2013. No secondary cases occurred. Thirty-five strains belonged to C:P1.5-1,10-8:F3-6:ST-11(cc11). Control measures have been adopted and immunisation campaigns implemented. Studies on risk factors and carriage are ongoing.

Evaluation of matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS) for identification and clustering of Neisseria gonorrhoeae.

BackgroundThe sexually transmitted infection gonorrhea remains a public health concern for becoming resistant to drug treatments available. The purpose of this study was to evaluate the usefulness of the matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS) to identify and cluster Neisseria gonorrhoeae.From a current monitoring in Italy, as part of the European Gonococcal Antimicrobial Surveillance Programme (EURO-GASP), 93 gonococci collected from 2007 to 2012 susceptible (44 isolates) and resistant (49 isolates) to cefixime were selected. Minimum Inhibitory Concentration (MIC) values for cefixime was assessed by Etest carried out in agreement with the manufacturer’s instructions and interpreted referring to European Committee on Antimicrobial Susceptibility testing (EUCAST) clinical breakpoints criteria. Data obtained by N. gonorrhoeae multiantigen sequence typing (NG-MAST) and the dendrogram based on the concatenation of porB and tbpB genes were evaluated. MALDI-TOF MS, to reconfirm gonorrhea identification, analyzed single colonies from freshly grown isolates and applied directly on a ground-steel MALDI target plate. For the MALDI-TOF dendrogram cluster analysis, MSPs (Main Spectrum Profile) from each isolate were created acquiring 5000 shots from 10 technical replicates obtained from bacteria extraction.ResultsMolecular typing by NG-MAST showed 28 sequence types (STs); G1407 was the predominant accounting for 75 gonococci. All the 93 gonococci, except one, were correctly identified at species level by MALDI-TOF MS and G1407 isolates were divided into two clusters.ConclusionMALDI-TOF MS for a real-time detection and cluster analysis of gonorrhea is a promising tool for surveillance purposes. Moreover, additional studies are required to collect more data on the performance of MALDI-TOF MS for gonococci.

Meningococci of serogroup X clonal complex 181 in refugee camps, Italy

Four cases of infection with serogroup X meningococci (MenX) (1 in 2015 and 3 in 2016) occurred in migrants living in refugee camps or reception centers in Italy. All MenX isolates were identified as clonal complex 181. Our report suggests that serogroup X represents an emerging health threat for persons arriving from African countries.

Severe pertussis infection in infants less than 6 months of age: Clinical manifestations and molecular characterization

ABSTRACT We conducted a study to determine the main traits of pertussis among unimmunized infants less than 6 months of age. From August 2012 to March 2015, 141 nasopharyngeal aspirates (NPAs) were collected from infants with respiratory symptoms attending 2 major hospitals in Rome. Clinical data were recorded and analyzed. Lab-confirmation was performed by culture and realtime PCR. B. pertussis virulence-associated genes (ptxP, ptxA and prn), together with multilocus variable-number tandem repeat analysis (MLVA), were also investigated by the sequence-based analysis on the DNAs extracted from positive samples. Antibiotic susceptibility with Etest was defined on 18 viable B. pertussis isolates. Samples from 73 infants resulted positives for B. pertussis. The median age of the patients was 45 d (range 7–165); 21 infants were treated with macrolides before hospital admission. Cough was reported for a median of 10 d before admission and 18 d after hospital discharge among infected infants, 84% of whom showed paroxysmal cough. No resistance to macrolides was detected. Molecular analysis identified MT27 as the predominant MLVA profile, combined with ptxP3-ptxA1-prn2 associated virulence genes. Although our data may not be generalized to the whole country, they provide evidence of disease severity among infants not vaccinated against pertussis. Moreover, genetically related B. pertussis strains, comprising allelic variants of virulence associated genes, were identified.

Epidemiological and Molecular Characterization of Invasive Meningococcal Disease in Italy, 2008/09-2012/13

Background Following the introduction of meningococcal serogroup C conjugate vaccine in Italy in 2005, changes in the epidemiology of Invasive Meningococcal Disease (IMD) were expected. The study aims were to describe the epidemiological trend and to characterize the isolates collected during the period 2008/09-2012/13 by multilocus sequence typing (MLST). Data on laboratory confirmed meningococcal diseases from National Surveillance System of IMD were reported. Methods Poisson regression models were used to estimate the incidence rate over time. Serogrouping and MLST were performed following published methods. Results The incidence rate of laboratory confirmed meningococcal disease decreased from 0.33 per 100,000 population in 2008/09 to 0.25 per 100,000 population in 2012/13. The serogroup B incidence rate was significantly higher (p<0.01) than that of other serogroups, among all age groups. The significant decrease of the IMD incidence rate (p = 0.01) reflects the decrease of serogroup B and C, in particular among individuals aged 15–24 years old (p<0.01). On the other hand, serogroup Y incidence increased during the period (from 0.01/100,000 in 2008/09 to 0.02/100,000 in 2012/13, p = 0.05). Molecular characterizations revealed that ST–41/44 cc and ST–11 cc were the main clonal complexes identified among serogroup B and C isolates, respectively. In particular, ST–41/44 cc was predominant in all age groups, whereas ST–11 cc was not identified in infants less than 1 year of age. Conclusions IMD incidence declined in Italy and serogroup B caused most of the IMD cases, with infants having the highest risk of disease. Continued surveillance is needed to provide information concerning further changes in circulating meningococci with special regard to serogroup distribution. Moreover, knowledge of meningococcal genotypes is essential to detect hyper-invasive strains.

Pertussis in infants less than 6 months of age and household contacts, Italy April 2014

We report pertussis cases in 4 infants less than 6 months admitted with symptoms compatible with pertussis to the intensive care unit of the Università Cattolica del Sacro Cuore in Rome, April 2014. Realtime PCR confirmed pertussis diagnosis for the 4 infants, 2 of them were cousins, and for the household contacts of 1 of them. Analysis of pertussis toxin, its promoter and pertactin was also performed. First of all, this report emphasizes the need to investigate household contact of infants with pertussis; secondly, to evaluate the selective vaccination of household members of newborns as an effective program to reduce pertussis in infants.

Persistent occurrence of serogroup Y/sequence type (ST)-23 complex invasive meningococcal disease among patients aged five to 14 years, Italy, 2007 to 2013

In Italy, the incidence of invasive meningococcal disease (IMD) has remained stable since 2007 (around 0.3 cases/100,000 inhabitants). However, as reported for other European countries, an increase of serogroup Y Neisseria meningitidis has been observed. In this study we report IMD cases from 2007 to 2013 in Italy and investigate the clinical and epidemiological features of cases affected by serogroup Y. Molecular characteristics of serogroup Y strains are also described. During the study period, the proportion of IMD cases due to serogroup Y increased, ranging from 2% in 2007 to 17% in 2013 (odds ratio (OR): 8.8), whereby the five to 14 years age group was mostly affected (p < 0.001). Overall 81 serogroup Y IMD cases were identified, with a median age of 18 years, ranging from three months to 84 years. Of the 81 respective patient samples, 56 were further subject to molecular typing. The sequence type (ST)-23 complex (clonal complex (cc)23) was predominant among serogroup Y meningococci (54/56 samples), and included nine different STs. Presumably, ST-23 was the founding genotype, with all the other STs presenting as single-locus variants. All cc23 isolates analysed harboured mutations in the lpxL1 gene; however, no associations among lpxL1 mutations, ST and age group were identified. Overall, these findings generate scientific evidence for the use of the quadrivalent meningococcal conjugate vaccine in the five to 14 years age group.

Molecular characterization of a collection of Neisseria meningitidis isolates from Croatia, June 2009 to January 2014.

In the last decade, the incidence of invasive meningococcal disease (IMD) in Croatia remained stable at approximately 1 case per 100 000 inhabitants, affecting mainly children aged ≤5 years. We report the molecular characterization of meningococci causing IMD occurring from June 2009 to January 2014 in Croatia. Genomic DNA from 50 clinical isolates was analysed for serogroup, multilocus sequence typing and allele type of the two outer membrane protein genes, porA and the iron-regulated fetA. Furthermore, 22 of them were characterized by using whole-genome sequencing to define the meningococcal vaccine four-component meningococcal serogroup B (4CMenB) antigen genes factor H-binding protein (fHbp), Neisseria heparin-binding antigen (nhba) and Neisseria adhesin A (nadA) and the antimicrobial target resistance genes for penicillin (penicillin binding protein 2, penA), ciprofloxacin (DNA gyrase subunit A, gyrA) and rifampicin (β-subunit of RNA polymerase, rpoB). The Etest was used to phenotypically determine the antimicrobial susceptibility of isolated meningococci. The main serogroup/clonal complex combinations were MenB cc41/44, MenC/cc11, MenW/cc174 and MenY/cc23. PorA P1.7-2, FetA F5-5 and F1-5 were the most represented through the serogroups. Meningococci with decreased susceptibility to penicillin (38.9 %) and one strain resistant to ciprofloxacin were identified. Forty-two percent of MenB showed the presence of at least one of the 4CMenB vaccine antigens (fHbp, NHBA, NadA and PorA). Our findings highlight the genetic variability of meningococci causing IMD in Croatia, especially for the serogroup B. Molecular-based characterization of meningococci is crucial to enhance IMD surveillance and to better plan national immunization programmes.

Pericarditis Caused by Hyperinvasive Strain of Neisseria meningitidis, Sardinia, Italy, 2015.

To the Editor: Invasive meningococcal disease is usually defined by the occurrence of meningitis or septicemia. Pericarditis might occur during the course of invasive infection. This clinical picture, defined as disseminated meningococcal disease with pericarditis (1) or secondary meningococcal pericarditis, was reported in 1918 (2). In 1939, primary or isolated meningococcal pericarditis (1,3) was described. In this form of pericarditis, pericardial or blood cultures are positive for Neisseria meningitidis but there is no meningeal involvement or clinical meningococcemia (4). Since its description, several cases of primary meningococcal pericarditis have been reported (5). Although its pathogenesis remains largely undefined, it has been hypothesized that the onset of primary pericarditis occurs after a transient bacteremia or as a consequence of involvement of the lower respiratory tract (4). Blaser et al. reported that serogroup C meningococci are usually associated with this disease, especially in adults. However, serogroups B, W, and Y have also been identified (4). We report a case-patient with primary meningococcal pericarditis caused by a serogroup C strain of N. meningitidis. The patient was a 32-year-old man who lived in Sardinia, Italy. He had no predisposing factors, such as immunodeficiency or other chronic disorders. Disease onset occurred on August 29, 2015. Clinical manifestations were fever (temperature 38°C), hypotension, epigastralgia, arthralgia, asthenia, chest pain, and reduced vesicular murmur. The left ventricle was widely hypokinetic, and a light ST increase was observed. A blood culture was positive for N. meningitidis. The patient was given piperacillin/tazobactam (4.5 g 3×/d) and metronidazole (500 mg 3×/d) for 4 days. After 4 days, treatment with ceftriaxone (2 g 2×/d) for 4 days was started. Because of persistent fever (38.8°C), levofloxacin (500 mg 2×/d) for 23 days was also started on day 7. On day 10, ceftriaxone was replaced with piperacillin/tazobactam (4.5 g 4×/d) for 21 days. A major bilateral pleural effusion was detected on the left side. On day 11, the fever had resolved. The outcome was favorable for this patient. Drug resistance of the strain was determined by using the MIC Test Strip Method (Liofilchem, Abruzzi, Italy). Breakpoints used were those recommended by the European Committee on Antimicrobial Susceptibility Testing version 5.0 (http://www.eucast.org/). The strain was susceptible to cefotaxime, ceftriaxone, ciprofloxacin, penicillin G, and rifampin. Serogroup was determined by using slide agglutination with commercial antisera (Remel Europe, Ltd., Dartford, UK) and confirmed by PCR (6). Whole-genome sequencing was conducted to obtain molecular data and enable comparison with other meningococci of the same serogroup that were isolated in Italy. Multilocus sequence typing (MLST) and typing of porA and fetA genes and Bexsero (meningcoccal group B vaccine) antigen genes (http://www.fda.gov/BiologicsBloodVaccines/Vaccines/ApprovedProducts/ucm431374.htm) were conducted as described (http://neisseria.org/). Whole-genome sequence was analyzed by using the BIGSdb Genome Comparator Tool (http://pubmlst.org/neisseria/). Genomes of meningococci belonging to the same finetype were compared by using the core genome MLST (cgMLST) approach. The N. meningitidis strain of serogroup C was susceptible to all antimicrobial drugs tested. Although serogroup C was associated with 53 (41%) of 132 invasive meningococcal disease cases in Italy in 2015 (http://www.iss.it/binary/mabi/cont/Report_MBI_20151223_v4.pdf), this serogroup has not been detected in Sardinia since 2010. Molecular analyses showed that the strain belonged to the hypervirulent clonal complex (cc) 11, sequence type (ST) 11. The complete finetype was C:5–1,10–8:F3–6:ST-11(cc11). This finetype has been reported in the United States and several countries in Europe (7), including Italy, and is responsible for several disease outbreaks. In Italy, this finetype represents 61% (70/115) of all serogroup C strains collected during 2012–2015. Two outbreaks caused by this strain were reported in Italy in 2007 (8) and in 2012 (9). The N. meningitidis factor H binding protein and heparin binding protein alleles were 1.13 and 20, respectively. The N. meningitidis adhesin A variant had an insertion sequence that disrupted this gene, as described for ET-15 meningococci (10). On the basis of results of cgMLST, the strain was determined to be related to strains responsible for an outbreak in Italy in 2015. In summary, we report a case of meningococcal pericarditis caused by a strain of N. meningitidis. This strain belongs to hyperinvasive clonal complex cc11 and was identified as C:P1.5–1,10–8:F3–6:ST-11(cc11), an emerging strain in Italy and worldwide. Timely diagnosis and complete molecular characterization of this strain, which causes a rare form of invasive disease (4), is needed for appropriate management of patients with this disease.

Draft Genome Sequence of Neisseria gonorrhoeae Sequence Type 1407, a Multidrug-Resistant Clinical Isolate

ABSTRACT Gonorrhea may become untreatable due to the spread of resistant or multidrug-resistant strains. Cefixime-resistant gonococci belonging to sequence type 1407 have been described worldwide. We report the genome sequence of Neisseria gonorrhoeae strain G2891, a multidrug-resistant isolate of sequence type 1407, collected in Italy in 2013.