Increase in penicillin-resistant invasive meningococcal serogroup W ST-11 complex isolates in England

Obstetric and Neonatal Invasive Meningococcal Disease Caused by Neisseria meningitidis Serogroup W, Western Australia, Australia

Three mother-baby pairs with invasive meningococcal disease occurred over 7 months in Western Australia, Australia, at a time when serogroup W sequence type 11 clonal complex was the predominant local strain. One mother and 2 neonates died, highlighting the role of this strain as a cause of obstetric and early neonatal death.

Emergence of ciprofloxacin- and penicillin-resistant Neisseria meningitidis isolates in Japan between 2003 and 2020 and its genetic features

Although we previously reported that some meningococcal isolates in Japan were resistant to penicillin (PCG) and ciprofloxacin (CIP), the antibiotic susceptibilities of Neisseria meningitidis isolates obtained in Japan remained unclear. In the present study, 290 N. meningitidis isolates in Japan between 2003 and 2020 were examined for the sensitivities to eight antibiotics (azithromycin, ceftriaxone, ciprofloxacin, chloramphenicol, meropenem, minocycline, penicillin, and rifampicin). All isolates were susceptible to chloramphenicol, ceftriaxone, meropenem, minocycline, and rifampicin while two were resistant to azithromycin. Penicillin- and ciprofloxacin-resistant and -intermediate isolates (PCGR, CIPR, PCGI and CIPI, respectively) were also identified. Based on our previous findings from whole genome sequence analysis, approximately 40% of PCGI were associated with ST-11026 and cc2057 meningococci, both of which were unique to Japan. Moreover, the majority of ST-11026 meningococci were CIPR or CIPI. Sensitivities to PCG and CIP were closely associated with genetic features, which indicated that, at least for Japanese meningococcal isolates, PCGR/I or CIPI/R would be less likely to be horizontally conferred from other neisserial genomes by transferring of the genes responsible (penA and gyrA genes, respectively), but rather that ancestral N. meningitidis strains conferring PCGR/I or CIPI/R phenotypes clonally disseminated in Japan.

Meningococcal Antibiotic Resistance: Molecular Characterization of Isolates from Patients with Invasive Meningococcal Disease (IMD) in Greece

For effective case management and chemoprophylaxis of Invasive Meningococcal Disease (IMD), prompt antibiotic treatment is required. N. meningitidis is usually susceptible to antibiotics, but reduced susceptibility to penicillin, ciprofloxacin, and rifampicin is increasing worldwide, jeopardizing patients' outcome. We assessed, phenotypically and genotypically, the antimicrobial resistance patterns of 192 strains isolated from IMD cases from all over Greece during 2010-2021. Antimicrobial susceptibility to penicillin, rifampicin, and ciprofloxacin was determined using the E-test. All isolates were genotyped by Multilocus Sequence Typing (MLST). penA, rpoB, and gyrA genes were amplified by PCR and sequenced. Of the 192 isolates, 37% (72/192) were penicillin-susceptible/had increased exposure, and 11% (21/192) were penicillin-resistant. Among those, 40 penA alleles were identified; penA1, penA27, and penA3 were highly associated with susceptibility to penicillin; penA14, penA25, and penA22 related to reduced susceptibility to penicillin, while penA9, penA910, and penA295 had resistance to penicillin. Two ciprofloxacin-resistant isolates harbored the gyrA346 allele, while one rifampicin-resistant isolate harbored the rpoB5 allele. Resistance to ciprofloxacin and rifampicin remains rare. As Greece is one of the countries with high antimicrobial resistance, continued monitoring of antibiotic resistance is important to ensure timely detection of emerging resistance for treatment and prevention guidelines.

Penicillin and Cefotaxime Resistance of Quinolone-Resistant Neisseria meningitidis Clonal Complex 4821, Shanghai, China, 1965-2020

Clonal complex 4821 (CC4821) Neisseria meningitidis, usually resistant to quinolones but susceptible to penicillin and third-generation cephalosporins, is increasing worldwide. To characterize the penicillin-nonsusceptible (PenNS) meningococci, we analyzed 491 meningococci and 724 commensal Neisseria isolates in Shanghai, China, during 1965-2020. The PenNS proportion increased from 0.3% in 1965-1985 to 7.0% in 2005-2014 and to 33.3% in 2015-2020. Of the 26 PenNS meningococci, 11 (42.3%) belonged to the CC4821 cluster; all possessed mutations in penicillin-binding protein 2, mostly from commensal Neisseria. Genetic analyses and transformation identified potential donors of 6 penA alleles. Three PenNS meningococci were resistant to cefotaxime, 2 within the CC4821 cluster. With 96% of the PenNS meningococci beyond the coverage of scheduled vaccination and the cefotaxime-resistant isolates all from toddlers, quinolone-resistant CC4821 has acquired penicillin and cefotaxime resistance closely related to the internationally disseminated ceftriaxone-resistant gonococcal FC428 clone, posing a greater threat especially to young children.

An analysis of Neisseria meningitidis strains causing meningococcal septic arthritis in England, and Wales: 2010-2020

OBJECTIVES

To analyse clinical meningococcal strains associated with meningococcal septic arthritis cases in England and Wales, and to identify associations between patient age, the synovial joint affected and strain characteristics.

METHODS

IMD cases confirmed by the Meningococcal Reference Unit (UK Health Security Agency) between January 2010 and December 2020 were included in the analysis. Septic arthritis cases were defined as those featuring detection and/or isolation of N. meningitidis from an articular site. Capsular grouping was performed by serology on clinical isolates and/or real-time PCR on clinical samples.

RESULTS

We identified 162 cases of meningococcal septic arthritis, representing 2% of all invasive meningococcal disease cases during the study period. The knee and the hip were the most commonly affected joints, with the former significantly more frequent in adults and the latter seen more commonly in children and adolescents. Group B strains were between 2 and 6 times less likely to cause septic arthritis in relation to groups W, C and Y strains.

CONCLUSIONS

Meningococcal septic arthritis remains a rare manifestation of invasive meningococcal disease. Strain and age associations identified in this study remain unexplained. Future analyses including clinical case information may help to explain these interesting findings.

Penicillin- and Ciprofloxacin-Resistant Invasive Neisseria meningitidis Isolates from Japan

Neisseria meningitidis causes a life-threatening invasive meningococcal disease (IMD). Isolates resistant to antibiotics, such as penicillin, ceftriaxone, and ciprofloxacin that are recommended for the treatment of IMD patients and their close contacts have been serious public health concerns globally. However, susceptibility profiles to critically important antibiotics and the genetic characteristics of isolates possessing antibiotic resistance are extremely limited as IMD incidence is low in Japan. We assessed the susceptibility profiles of 87 randomly selected, sterile site-derived N. meningitidis strains isolated from hospitals nationwide, recovered between April 1998 and March 2018 in Japan, to seven antibiotics. As a result, we demonstrated, for the first time, that the isolates remained highly susceptible to ceftriaxone, meropenem, azithromycin, ciprofloxacin, chloramphenicol, and rifampin, but not to penicillin. We then characterized the genetic relatedness of six penicillin- and/or ciprofloxacin-resistant isolates obtained in this study with global 112 genomes using core-genome phylogenetic analysis. These results provide the first evidence that invasive lineages such as a penicillin-resistant serogroup W, sequence type (ST)-11 clonal complex (CC), and a ciprofloxacin-resistant serogroup B/C, ST-4821 CC that is considered as a global threat, have been sporadically identified in Japan. Our findings highlight the need to monitor antibiotic resistance in clinical isolates of N. meningitidis, thereby preventing the spread of antibiotic-resistant invasive lineages and maintaining effective treatment for IMD patients and their close contacts. IMPORTANCE Although antibiotics such as penicillin and ceftriaxone can treat invasive meningococcal disease (IMD), the emergence and spread of antibiotic-resistant Neisseria meningitidis have become a global concern. To provide effective treatment, including chemoprophylaxis to IMD patients and their close contacts, we highlighted the importance of recognizing the antibiotic resistance and genetic features of N. meningitidis isolates.

Antibiotic resistance among invasive Neisseria meningitidis isolates in England, Wales and Northern Ireland (2010/11 to 2018/19)

Invasive meningococcal disease (IMD), caused by Neisseria meningitidis, can have a fatality rate as high as 10%, even with appropriate treatment. In the UK, penicillin is administered to patients in primary care whilst third generation cephalosporins, cefotaxime and ceftriaxone, are administered in secondary care. The first-choice antibiotic for chemoprophylaxis of close contacts is ciprofloxacin, followed by rifampicin. Immunocompromised individuals are often recommended antibiotic chemoprophylaxis and vaccination due to a greater risk of IMD. Resistance to antibiotics among meningococci is relatively rare, however reduced susceptibility and resistance to penicillin are increasing globally. Resistance to third generation cephalosporins is seldom reported, however reduced susceptibility to both cefotaxime and ceftriaxone has been observed. Rifampicin resistance has been reported among meningococci, mainly following prophylaxis, and ciprofloxacin resistance, whilst uncommon, has also been reported across the globe. The Public Health England Meningococcal Reference Unit receives and characterises the majority of isolates from IMD cases in England, Wales and Northern Ireland. This study assessed the distribution of antibiotic resistance to penicillin, rifampicin, ciprofloxacin and cefotaxime among IMD isolates received at the MRU from 2010/11 to 2018/19 (n = 4,122). Out of the 4,122 IMD isolates, 113 were penicillin-resistant, five were ciprofloxacin-resistant, two were rifampicin-resistant, and one was cefotaxime-resistant. Penicillin resistance was due to altered penA alleles whilst rifampicin and ciprofloxacin resistance was due to altered rpoB and gyrA alleles, respectively. Cefotaxime resistance was observed in one isolate which had an altered penA allele containing additional mutations to those harboured by the penicillin-resistant isolates. This study identified several isolates with resistance to antibiotics used for current treatment and prophylaxis of IMD and highlights the need for continued surveillance of resistance among meningococci to ensure continued effective use.