Genetic variability of Polish serogroup B meningococci (2010–2016) including the 4CMenB vaccine component genes

International audienceNeisseria meningitidis serogroup B (MenB) has recently become the major cause of invasive meningococcal disease in Poland. Therefore, the purpose of this study was to characterize MenB isolates, responsible for invasive meningococcal disease in 2010-2016, by MLST and sequencing of genes encoding proteins used as 4CMenB vaccine antigens. Two methods of coverage estimation were performed: extrapolation of MATS results of Polish meningococci 2010-2011 (exMATS) and gMATS, which combines genotyping and MATS results. Among 662 isolates 20 clonal complexes (CC) were detected, of which the most frequent were CC32, CC41/44 and CC18, accounting for 31.9%, 16.5% and 12.7%, respectively. A total of 111 combinations of PorA variable regions (VR1/VR2) were found, with P1.7,16 (15.0%) and P1.22,14 (13.6%) being prevalent. Vaccine variant VR2:4 was detected in 7.3% of isolates, mainly representing CC41/44 and non-assigned CC. Eighty five fHbp alleles encoding 74 peptide subvariants were revealed. Subvariant 1.1, a component of 4CMenB, was prevalent (24.2%) and found generally in CC32. Typing of the nhba gene revealed 102 alleles encoding 87 peptides. The most frequent was peptide 3 (22.4%), whereas vaccine peptide 2 was detected in 9.8%, mostly among CC41/44. The nadA gene was detected in 34.0% of isolates and the most prevalent was peptide 1 (variant NadA-1; 71.6%), found almost exclusively in CC32 meningococci. Vaccine peptide 8 (variant NadA-2/3) was identified once. Consequently, 292 completed BAST profiles were revealed. Regarding vaccine coverage, 39.7% of isolates had at least one 4CMenB vaccine variant, but according to exMATS and gMATS the coverage was 83.3% and 86.6%, respectively. In conclusion, Polish MenB (2010-2016) was highly diverse according to MLST and gene alleles encoding 4CMenB vaccine antigens. Some correlations between clonal complexes and variants of examined proteins/BAST profiles were revealed and a high coverage of 4CMenB vaccine was estimated

Highly Resistant Serotype 19A Streptococcus pneumoniae of the GPSC1/CC320 Clone from Invasive Infections in Poland Prior to Antipneumococcal Vaccination of Children

Abstract Introduction The introduction of pneumococcal conjugate vaccines (PCV) into the national immunization programs (NIPs) has significantly reduced the number of pneumococcal infections. However, infections caused by isolates of non-vaccine serotypes (NVT) started spreading shortly thereafter and strains of NVT 19A have become the main cause of invasive pneumococcal disease burden worldwide. The aim of the study was to characterize serotype 19A invasive pneumococci of GPSC1/CC320 circulating in Poland before the introduction of PCV into the Polish NIP in 2017 and to compare them to isolates from other countries where PCVs were implemented much earlier than in Poland. Methods All the GPSC1/CC320 isolates were analyzed by serotyping, susceptibility testing, and whole genome sequencing followed by analyses of resistome, virulome, and core genome multilocus sequence typing (cgMLST), including comparative analysis with isolates with publicly accessible genomic sequences (PubMLST). Results During continuous surveillance the NRCBM collected 4237 invasive Streptococcus pneumoniae isolates between 1997 and 2016, including 200 isolates (4.7%) of serotype 19A. The most prevalent among 19A pneumococci were highly resistant representatives of Global Pneumococcal Sequence Cluster 1/Clonal Complex 320, GPSC1/CC320 (n = 97, 48.5%). Isolates of GPSC1/CC320 belonged to three sequence types (STs): ST320 (75.2%) ST4768 (23.7%), and ST15047 (1.0%), which all represented the 19A-III cps subtype and had complete loci for both PI-1 and PI-2 pili types. On the basis of the cgMLST analysis the majority of Polish GPSC1/CC320 isolates formed a group clearly distinct from pneumococci of this clone observed in other countries. Conclusion Before introduction of PCV in the Polish NIP we noticed an unexpected increase of serotype 19A in invasive pneumococcal infections, with the most common being representatives of highly drug-resistant GPSC1/CC320 clone, rarely identified in Europe both before and even after PCV introduction

A decade of invasive meningococcal disease surveillance in Poland.

Neisseria meningitidis is a leading etiologic agent of severe invasive disease. The objective of the study was to characterise invasive meningococcal disease (IMD) epidemiology in Poland during the last decade, based on laboratory confirmed cases.The study encompassed all invasive meningococci collected between 2002 and 2011 in the National Reference Centre for Bacterial Meningitis. The isolates were re-identified and characterised by susceptibility testing, MLST analysis, porA and fetA sequencing. A PCR technique was used for meningococcal identification directly from clinical materials.In the period studied, 1936 cases of IMD were confirmed, including 75.6% identified by culture. Seven IMD outbreaks, affecting mostly adolescents, were reported; all were caused by serogroup C meningococci of ST-11. The highest incidence was observed among children under one year of age (15.71/100,000 in 2011). The general case fatality rate in the years 2010-2011 was 10.0%. Meningococci of serogroup B, C, Y and W-135 were responsible for 48.8%, 36.6%, 1.2% and 1.2% of cases, respectively. All isolates were susceptible to third generation cephalosporins, chloramphenicol, ciprofloxacin, and 84.2% were susceptible to penicillin. MLST analysis (2009-2011) revealed that among serogroup B isolates the most represented were clonal complexes (CC) ST-32CC, ST-18CC, ST-41/44CC, ST-213CC and ST-269CC, and among serogroup C: ST-103CC, ST-41/44CC and ST-11CC.The detection of IMD in Poland has changed over time, but observed increase in the incidence of the disease was mostly attributed to changes in the surveillance system including an expanded case definition and inclusion of data from non-culture diagnostics

Map of Poland with the incidence rates (per 100,000) of invasive meningococcal disease in children under 1 year of age/all age groups, in 16 voivodeships, in years 2010–2011.

<p>The voivodeships with notified outbreaks during study period are marked in yellow (OUT. – outbreak, numbered like in the text, the year of the outbreak, in bracket there is number of outbreak cases).</p

Molecular characterization of meningococcal isolates of serogroup B and C belonging to the most dominant clonal complexes (CC) represented at least by 10 isolates, 2009–2011.

a<p>ST – sequence type.</p

Serogroup distribution of meningococci responsible for invasive infections in Poland, 2002–2011.

<p>(n = 1936; UNK - cases with unknown serogroup).</p

The total annual incidence rates (/100,000) of invasive meningococcal disease (IMD)/meningitis rates in age groups in Poland based on laboratory-confirmed cases, including culture- and PCR-positive samples, 2002–2011 (only cases with known age were included when calculating the incidence) and total annual incidence rates of IMD registered by the compulsory notification system (NIPH-NIH).

a<p>%Cases <b>-</b> percentage of IMD cases in age group among all cases;</p>b<p>No cases - total number of cases in a particular year;</p>c<p>percentage of cases identified by PCR in a particular year;</p>d<p>Men-cult. - incidence rates of meningitis confirmed by culture only;</p>e<p>NIPH-NIH – total incidence of invasive meningococcal disease for all age groups registered by compulsory notification system run by the National Institute of Public Health – National Institute of Hygiene (Available: <a href="http://www.pzh.gov.pl/oldpage/epimeld/index_p.html" target="_blank">http://www.pzh.gov.pl/oldpage/epimeld/index_p.html</a>. Accessed 2013 May 24).</p

Incidence of invasive meningococcal disease (/100,000) case fatality rate (CFR) and percentage of cases with sequelae in age groups in Poland, 2010–2011 (only cases with known outcome were included when calculating the CFR, n = 458).

a<p>MenB CFR - case fatality rate associated with infections caused by serogroup B meningococci;</p>b<p>MenC CFR - case fatality rate associated with infections caused by serogroup C meningococci.</p