Genetic diversity and clonal characteristics of ciprofloxacin-resistant meningococcal strains in China

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.

The resistance mechanisms of bacteria against ciprofloxacin and new approaches for enhancing the efficacy of this antibiotic

For around three decades, the fluoroquinolone (FQ) antibiotic ciprofloxacin has been used to treat a range of diseases, including chronic otorrhea, endocarditis, lower respiratory tract, gastrointestinal, skin and soft tissue, and urinary tract infections. Ciprofloxacin's main mode of action is to stop DNA replication by blocking the A subunit of DNA gyrase and having an extra impact on the substances in cell walls. Available in intravenous and oral formulations, ciprofloxacin reaches therapeutic concentrations in the majority of tissues and bodily fluids with a low possibility for side effects. Despite the outstanding qualities of this antibiotic, Salmonella typhi, Staphylococcus aureus, Escherichia coli, and Pseudomonas aeruginosa have all shown an increase in ciprofloxacin resistance over time. The rise of infections that are resistant to ciprofloxacin shows that new pharmacological synergisms and derivatives are required. To this end, ciprofloxacin may be more effective against the biofilm community of microorganisms and multi-drug resistant isolates when combined with a variety of antibacterial agents, such as antibiotics from various classes, nanoparticles, natural products, bacteriophages, and photodynamic therapy. This review focuses on the resistance mechanisms of bacteria against ciprofloxacin and new approaches for enhancing its efficacy.

Demographic Features of Invasive Meningococcal Disease in Taiwan, 1993 to 2020, and Genetic Characteristics of Neisseria meningitidis Isolates, 2003 to 2020

We present the demographic features of invasive meningococcal disease (IMD) in Taiwan between 1993 and 2020 and the genetic characteristics of Neisseria meningitidis isolates recovered from 2003 to 2020. IMD was rare in Taiwan between 1993 and 2020, with an annual incidence ranging from 0.009 to 0.204 per 100,000 people. The case fatality rate (CFR) declined from 18.1% for patients in 1993 to 2002 to 9.8% in 2003 to 2020. Infants less than 12 months were most susceptible to the disease. N. meningitidis serogroup B (NmB) was most predominant, responsible for 81.2% (134/165) of the IMD cases in 2003 to 2020. The majority of the isolates recovered from 2003 to 2020 belonged to 4 worldwide-spread hyperinvasive clonal complexes (cc), cc4821 (30.3%), cc32 (19.4%), cc41/44 (12.7%), cc23 (7.3%), and also a newly assigned clonal complex, cc3439 (10.3%). Core genome multilocus sequence typing (cgMLST) profile comparisons revealed that the cc4821 isolates with a T-to-I substitution at position 91 in gyrA were closely related to those originating from China. Of the 165 isolates, 20.0% and 53.3% were predicted to be covered by the Bexsero and Trumenba vaccines, respectively, whereas, 77.0% and 46.7% remained indeterminate. In conclusion, N. meningitidis isolates recovered in Taiwan between 2003 and 2020 were mostly highly diverse. Most IMD cases appeared sporadically and were caused by localized strains, although some patients were infected by recently introduced strains. cgMLST is a powerful tool for the rapid comparison of genetic relatedness among a large number of isolates. cgMLST profiling, based on 1,241 core genes, and strain tracking can be performed on the website of cgMLST@Taiwan (http://rdvd.cdc.gov.tw/cgMLST/). IMPORTANCE N. meningitidis can cause life-threatening invasive meningococcal disease (IMD), including meningitis and sepsis, resulting in a high CFR and long-term sequelae in survivors. Here, we report the demographic features of IMD in Taiwan over a 28-year period (1993 to 2020) and the genetic characteristics of N. meningitidis isolates recovered from patients with IMD over an 18-year period (2003 to 2020). We conducted a whole-genome sequence analysis to characterize the genetic features of the isolates and developed a cgMLST scheme for epidemiological investigation and strain tracking. The findings can be beneficial in understanding the epidemiology of IMD in Taiwan, the genetic characteristics of the bacterial strains, and the distribution of vaccine antigens for vaccine development and implementation.

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.

Surveillance and control of meningococcal disease in the COVID-19 era: A Global Meningococcal Initiative review

This review article incorporates information from the 4th Global Meningococcal Initiative summit meeting. Since the introduction of stringent COVID-19 infection control and lockdown measures globally in 2020, there has been an impact on IMD prevalence, surveillance, and vaccination compliance. Incidence rates and associated mortality fell across various regions during 2020. A reduction in vaccine uptake during 2020 remains a concern globally. In addition, several Neisseria meningitidis clonal complexes, particularly CC4821 and CC11, continue to exhibit resistance to antibiotics, with resistance to ciprofloxacin or beta-lactams mainly linked to modifications of gyrA or penA alleles, respectively. Beta-lactamase acquisition was also reported through horizontal gene transfer (bla_ROB-1) involving other bacterial species. Despite the challenges over the past year, progress has also been made on meningococcal vaccine development, with several pentavalent (serogroups ABCWY and ACWYX) vaccines currently being studied in late-stage clinical trial programmes.

Acquisition of ciprofloxacin resistance among an expanding clade of β-lactamase positive, serogroup Y Neisseria meningitidis in the United States

BACKGROUND

Penicillin and ciprofloxacin are important for invasive meningococcal disease (IMD) management and prevention. IMD cases caused by penicillin- and ciprofloxacin-resistant Neisseria meningitidis containing a ROB-1 β-lactamase gene (blaROB-1) and a mutated DNA gyrase gene (gyrA), have been recently reported in the USA.

METHODS

We examined 2097 meningococcal genomes collected through US population-based surveillance from January 2011-February 2020 to identify IMD cases caused by strains with blaROB-1 or gyrA-mediated resistance. Antimicrobial resistance was confirmed phenotypically. The US isolate genomes were compared to non-US isolate genomes containing blaROB-1. Interspecies transfer of ciprofloxacin resistance was assessed by comparing gyrA among Neisseria species.

RESULTS

Eleven penicillin- and ciprofloxacin-resistant isolates were identified after December 2018; all were serogroup Y, sequence type 3587, clonal complex (CC) 23, and contained blaROB-1 and a T91I-containing gyrA allele. An additional 22 penicillin-resistant, blaROB-1-containing US isolates with wild-type gyrA were identified from 2013-2020. All 33 blaROB-1-containing isolates formed a single clade, along with 12 blaROB-1-containing isolates from six other countries. Two-thirds of blaROB-1-containing US isolates were from Hispanic individuals. Twelve additional ciprofloxacin-resistant isolates with gyrA T91 mutations were identified. Ciprofloxacin-resistant isolates belonged to six CCs and contained 10 unique gyrA alleles; seven were similar or identical to alleles from N. lactamica or N. gonorrhoeae.

CONCLUSIONS

Recent IMD cases caused by a dual resistant serogroup Y suggest changing antimicrobial resistance patterns in the USA. The emerging dual-resistance is due to acquisition of ciprofloxacin resistance by β-lactamase-containing N. meningitidis. Routine antimicrobial resistance surveillance will effectively monitor resistance changes and spread.

Antibiotic susceptibility and molecular analysis of invasive Neisseria meningitidis recovered in the Republic of Ireland, 1996 to 2016

This study examined the antimicrobial susceptibility of invasive meningococcal disease (IMD)-associated Neisseria meningitidis recovered in the Republic of Ireland between 1996 and 2016. In total, 1359 isolates representing over one-third of all laboratory-confirmed cases of IMD diagnosed each epidemiological year (EY; July 1-June 30) were analysed. All isolates were susceptible to ciprofloxacin, rifampicin and cefotaxime and 74% and 87% were susceptible to sulphonamide and penicillin, respectively. The proportion of isolates exhibiting reduced susceptibility to penicillin increased significantly during the study with no evidence of major clonal expansion or horizontal spread of a specific penA allele. Greater diversity observed among recently recovered meningococci and specifically among isolates exhibiting reduced penicillin susceptibility contributed to the overall increase in penA allele diversity throughout. The emergence and dissemination of strains with phenotypic and genotypic reduced susceptibility to penicillin increase the need for continued surveillance of antimicrobial susceptibility of meningococci in the Republic of Ireland especially in view of the recommendation of penicillin G as empiric treatment of choice for pre-hospital management.

Emergence of ciprofloxacin-resistant Neisseria meningitidis B from asymptomatic carriers during an outbreak in Peru, 2017

Asymptomatic carriers are a likely source of transmission of Neisseria meningitidis to close contacts who are placed at a higher risk for invasive meningococcal disease (IMD). Although N. meningitidis ciprofloxacin-resistance is rare, there have been an increase in the reports of resistant isolates mainly in patients diagnosed with IMD, and little is known about the N. meningitidis ciprofloxacin-resistance in the carrier populations. We performed a pharyngeal carriage study during a 2017 military setting outbreak in Peru, caused by a ciprofloxacin-resistant N. meningitidis B. The isolates analysed came from two hospitalized cases and six asymptomatic carriers. Whole-genome sequence-based analysis was performed and showed that strains carrying the Thr91Ile mutation, in the gene encoding for subunit A of DNA gyrase (gyrA), were responsible for the fluoroquinolone resistance (MICs ≥0.256 µg ml^-1) and were closely related to highly virulent strains from France, Norway and the UK. Phylogenetic analysis of the gyrA gene revealed that likely these Peruvian isolates acquired resistance through horizontal gene transfer from Neisseria lactamica. Our study provides evidence for the emergence and propagation of ciprofloxacin-resistant N. meningitidis B from asymptomatic carriers, and recommends the introduction of serogroup B vaccines for high-risk populations.

Geographically widespread invasive meningococcal disease caused by a ciprofloxacin resistant non-groupable strain of the ST-175 clonal complex

INTRODUCTION

Invasive meningococcal disease (IMD) caused by non-serogroupable (NG) strains mainly affects immunocompromised individuals. Reduced susceptibility to penicillin in meningococci is increasing in Europe but ciprofloxacin resistance remains rare. In 2019, three travel-related meningococcal disease cases caused by a ciprofloxacin-resistant NG strain were identified in England, leading Germany to report four additional IMD cases (2016 to 2019). We describe these and newly identified cases and characterise the strain responsible.

METHODS

Cases were identified as part of national surveillance and by analysing available genomes using PubMLST tools.

RESULTS

Of the cases identified in England in 2019, two geographically distinct cases developed conjunctivitis after returning from Mecca (Kingdom of Saudi Arabia) and a third linked case presented with IMD. Of the four cases from Germany, three occurred in asylum seekers - two familial and a further geographically distinct case. Further IMD cases were identified in Italy (n = 2; 2017-2018), Sweden (n = 1; 2016) and England (n = 1; 2015). A single ST-175 clonal complex (cc175) strain with genosubtype P1.22-11,15-25 was responsible. Decreased susceptibility to penicillin was widespread with three ciprofloxacin resistant subclusters. Constituent isolates were potentially covered by subcapsular vaccines.

CONCLUSION

This disease associated NG cc175 strain exhibits resistance to antibiotics commonly used to prevent IMD but is potentially covered by subcapsular (meningococcal B) vaccines.

Meningococcal disease surveillance in the Asia-Pacific region (2020): The global meningococcal initiative

The degree of surveillance data and control strategies for invasive meningococcal disease (IMD) varies across the Asia-Pacific region. IMD cases are often reported throughout the region, but the disease is not notifiable in some countries, including Myanmar, Bangladesh and Malaysia. Although there remains a paucity of data from many countries, specific nations have introduced additional surveillance measures. The incidence of IMD is low and similar across the represented countries (<0.2 cases per 100,000 persons per year), with the predominant serogroups of Neisseria meningitidis being B, W and Y, although serogroups A and X are present in some areas. Resistance to ciprofloxacin is also of concern, with the close monitoring of antibiotic-resistant clonal complexes (e.g., cc4821) being a priority. Meningococcal vaccination is only included in a few National Immunization Programs, but is recommended for high-risk groups, including travellers (such as pilgrims) and people with complement deficiencies or human immunodeficiency virus (HIV). Both polysaccharide and conjugate vaccines form part of recommendations. However, cost and misconceptions remain limiting factors in vaccine uptake, despite conjugate vaccines preventing the acquisition of carriage.

Evolutionary analysis of gyrA gene from Neisseria meningitidis bacterial strains of clonal complex 4821 collected in China between 1978 and 2016

BACKGROUND

Neisseria meningitidis (N.meningitidis) bacteria belonging to clonal complex 4821 (CC4821) have been mainly reported in China and have been characterized by a high resistance rate to ciprofloxacin (CIP). The aim of this study was to assess the evolution of the DNA gyrase A (gyrA) gene from N.meningitidis CC4821 strains collected in China between 1978 and 2016. The complete sequence of gyrA gene from 77 strains are reported in this study and analyzed in the context of publicly available sequences from N. meningitidis of other CCs as well as other Neisseria species.

RESULTS

The phylogenetic analysis of CC4821 gyrA gene reveals at least 5 distinct genetic clusters. These clusters are not CC4821-specific showing that gyrA evolution is independent of CC4821 evolution. Some clusters contain sequences from other Neisseria species. Recombination within N.meningitidis strains and between Neisseria species was identified in SimPlot analysis. Finally, amino acid substitutions within GyrA protein were analyzed. Only one position, 91 (83 in E.coli gyrA gene), was linked to CIP resistance. Thirty-one additional putative resistance markers were identified, as amino acid substitutions were only found in resistant strains.

CONCLUSIONS

The evolution of gyrA gene of CC4821 N.meningitidis strains is not dependent on CC4821 evolution or on CIP resistance phenotype. Only amino acid 91 is linked to CIP resistance phenotype. Finally, recombination inter- and intra-species is likely to result in the acquisition of various resistance markers, 31 of them being putatively mapped in the present study. Analyzing the evolution of gyrA gene within CC4821 strains is critical to monitor the CIP resistance phenotype and the acquisition of new resistance markers. Such studies are necessary for the control of the meningococcal disease and the development of new drugs targeting DNA gyrase.

Meningococcal Quinolone Resistance Originated from Several Commensal Neisseria Species

Quinolone resistance is increasing in Neisseria meningitidis, with its prevalence in China being high (>70%), but its origin remains unknown. The aim of this study was to investigate the donors of mutation-harboring gyrA alleles in N. meningitidis A total of 198 N. meningitidis isolates and 293 commensal Neisseria isolates were collected between 2005 and 2018 in Shanghai, China. The MICs of ciprofloxacin were determined using the agar dilution method. The resistance-associated genes gyrA and parC were sequenced for all isolates, while a few isolates were sequenced on the Illumina platform. The prevalences of quinolone resistance in the N. meningitidis and commensal Neisseria isolates were 67.7% (134/198) and 99.3% (291/293), respectively. All 134 quinolone-resistant N. meningitidis isolates possessed mutations in T91 (n = 123) and/or D95 (n = 12) of GyrA, with 7 isolates also harboring ParC mutations and exhibiting higher MICs. Phylogenetic analysis of the gyrA sequence identified six clusters. Among the 71 mutation-harboring gyrA alleles found in 221 N. meningitidis isolates and genomes (n = 221), 12 alleles (n = 103, 46.6%) were included in the N. meningitidis cluster, while 20 alleles (n = 56) were included in the N. lactamica cluster, 27 alleles (n = 49) were included in the N. cinerea cluster, and 9 alleles (n = 10) were included in the N. subflava cluster. Genomic analyses identified the exact N. lactamica donors of seven mutation-harboring gyrA alleles (gyrA92, gyrA97, gyrA98, gyrA114, gyrA116, gyrA151, and gyrA230) and the N. subflava donor isolate of gyrA171, with the sizes of the recombinant fragments ranging from 634 to 7,499 bp. Transformation of gyrA fragments from these donor strains into a meningococcal isolate increased its ciprofloxacin MIC from 0.004 μg/ml to 0.125 or 0.19 μg/ml and to 0.5 μg/ml with further transformation of an additional ParC mutation. Over half of the quinolone-resistant N. meningitidis isolates acquired resistance by horizontal gene transfer from three commensal Neisseria species. Quinolone resistance in N. meningitidis increases in a stepwise manner.

Prevention and control of meningococcal disease: Updates from the Global Meningococcal Initiative in Eastern Europe

The Global Meningococcal Initiative (GMI) aims to prevent invasive meningococcal disease (IMD) worldwide through education, research and cooperation. In March 2019, a GMI meeting was held with a multidisciplinary group of experts and representatives from countries within Eastern Europe. Across the countries represented, IMD surveillance is largely in place, with incidence declining in recent decades and now generally at <1 case per 100,000 persons per year. Predominating serogroups are B and C, followed by A, and cases attributable to serogroups W, X and Y are emerging. Available vaccines differ between countries, are generally not included in immunization programs and provided to high-risk groups only. Available vaccines include both conjugate and polysaccharide vaccines; however, current data and GMI recommendations advocate the use of conjugate vaccines, where possible, due to the ability to interrupt the acquisition of carriage. Ongoing carriage studies are expected to inform vaccine effectiveness and immunization schedules. Additionally, IMD prevention and control should be guided by monitoring outbreak progression and the emergence and international spread of strains and antibiotic resistance through use of genomic analyses and implementation of World Health Organization initiatives. Protection of high-risk groups (such as those with complement deficiencies, laboratory workers, migrants and refugees) is recommended.

Prevalence, sequence type, and quinolone resistance of Neisseria lactamica carried in children younger than 15 years in Shanghai, China

OBJECTIVE

Neisseria lactamica has an important influence on carriage and antimicrobial susceptibility of N. meningitidis, a major pathogen of septicemia and meningitis. In China, quinolone resistance is highly prevalent in N. meningitidis but unknown in N. lactamica. This study investigates the carriage rate, sequence type, and ciprofloxacin resistance of N. lactamica in children in China.

METHODS

During 2014-2016, throat swabs were collected from 2,239 children in Shanghai. The ciprofloxacin minimum inhibitory concentrations of the isolates were determined by the agar dilution method.

RESULTS

The overall carriage rate of N. lactamica was higher (8.9%) than that of N. meningitidis (0.9%) and peaked at two years (37.1%). The resistance frequency of N. lactamica to ciprofloxacin was 98.5% (197/200). There were 65 sequence types (STs). Clonal complex (cc) 640 (45.5%) dominated, while ST-14031 was predominant (37%, 74/200). All isolates possessed a GyrA mutation; 17 isolates (8.5%) harbored additionally a ParC mutation. Assigned to 39 different alleles, the gyrA sequences from these N. lactamica isolates formed an N. lactamica cluster, which also included eight alleles from N. meningitidis.

CONCLUSION

The N. lactamica isolates in China showed distinct characteristics with lower genetic diversity and a much higher prevalence of quinolone resistance than in other countries.

Evolution of Sequence Type 4821 Clonal Complex Meningococcal Strains in China from Prequinolone to Quinolone Era, 1972-2013

The expansion of hypervirulent sequence type 4821 clonal complex (CC4821) lineage Neisseria meningitidis bacteria has led to a shift in meningococcal disease epidemiology in China, from serogroup A (MenA) to MenC. Knowledge of the evolution and genetic origin of the emergent MenC strains is limited. In this study, we subjected 76 CC4821 isolates collected across China during 1972–1977 and 2005–2013 to phylogenetic analysis, traditional genotyping, or both. We show that successive recombination events within genes encoding surface antigens and acquisition of quinolone resistance mutations possibly played a role in the emergence of CC4821 as an epidemic clone in China. MenC and MenB CC4821 strains have spread across China and have been detected in several countries in different continents. Capsular switches involving serogroups B and C occurred among epidemic strains, raising concerns regarding possible increases in MenB disease, given that vaccines in use in China do not protect against MenB.

The Global Meningococcal Initiative meeting on prevention of meningococcal disease worldwide: Epidemiology, surveillance, hypervirulent strains, antibiotic resistance and high-risk populations

INTRODUCTION

The 2018 Global Meningococcal Initiative (GMI) meeting focused on evolving invasive meningococcal disease (IMD) epidemiology, surveillance, and protection strategies worldwide, with emphasis on emerging antibiotic resistance and protection of high-risk populations. The GMI is comprised of a multidisciplinary group of scientists and clinicians representing institutions from several continents.

AREAS COVERED

Given that the incidence and prevalence of IMD continually varies both geographically and temporally, and surveillance systems differ worldwide, the true burden of IMD remains unknown. Genomic alterations may increase the epidemic potential of meningococcal strains. Vaccination and (to a lesser extent) antimicrobial prophylaxis are the mainstays of IMD prevention. Experiences from across the globe advocate the use of conjugate vaccines, with promising evidence growing for protein vaccines. Multivalent vaccines can broaden protection against IMD. Application of protection strategies to high-risk groups, including individuals with asplenia, complement deficiencies and human immunodeficiency virus, laboratory workers, persons receiving eculizumab, and men who have sex with men, as well as attendees at mass gatherings, may prevent outbreaks. There was, however, evidence that reduced susceptibility to antibiotics was increasing worldwide.

EXPERT COMMENTARY

The current GMI global recommendations were reinforced, with several other global initiatives underway to support IMD protection and prevention.

Emergence and spread of resistant N. meningitidis implicated in invasive meningococcal diseases during the past decade (2008-2017)

Neisseria meningitidis is one of the most crucial causes of bacterial meningitis worldwide. The incidence of meningitis due to N. meningitidis greatly changes from one geographical area to the other: 500,000-1,200,000 invasive meningococcal diseases occur each year, with 50,000-135,000 deaths. Once the diagnosis of bacterial meningitis is made, parenteral antibiotic treatment is started as soon as possible. A preventive treatment can also be proposed for those subjects at risk of exposure. Globally, resistance to antibiotics used in the treatment of prophylaxis of meningococcal disease is relatively rare. Penicillin is becoming less useful in the treatment of invasive meningococcal diseases because meningococcal isolates are increasingly less susceptible to this antibiotic. Meningococcal strains less susceptible to ceftriaxone or ciprofloxacin are rare. In addition, resistance to rifampicin is not a current concern as resistant isolates are rarely reported. In conclusion, the emergence of new meningococcal strains with decreasing susceptibility during the last decade should not be ignored, as this could be a worrying phenomenon in the future and justifies a judicious epidemiological survey on a continuous basis.

Invasive meningococcal disease due to ciprofloxacin-resistant Neisseria meningitidis sequence type 4821: The first case in Japan

We present a 4-year-old girl who developed invasive meningococcal disease (IMD) caused by Neisseria meningitidis serogroup C sequence type (ST)-4821. She was hospitalized due to fever, vomiting, rash and altered consciousness. Serogroup C N. meningitidis was isolated from blood culture taken on admission and was confirmed by matrix-assisted laser desorption ionization time-of-flight mass spectrometry, a biochemical test, and molecular microbiological analysis. The patient was successfully treated with 50 mg/kg ceftriaxone every 12 hours for 7 days without any complications. The isolate was susceptible to a wide variety of β-lactams and rifampin but was resistant to ciprofloxacin. The isolate harbored gyrA T91I and parC S87I mutations at the quinolone-resistance-determining regions. Multi-locus sequence typing revealed the isolates as ST-4821, which was identical to an endemic clone frequently detected in China. However, neither the patient nor her family members had traveled abroad. To our knowledge, this report is the first to describe an IMD patient caused by ciprofloxacin-resistant N. meningitidis ST-4821 in Japan, and is the first community-acquired IMD case due to this strain outside of China. The high proportion of ciprofloxacin resistance and hypervirulent features of this ST-4821 strain raise special public health concerns. We still consider ciprofloxacin is still appropriate drug for post-exposure chemoprophylaxis in Japan. However, nationwide surveillance for susceptibility of IMD isolates is necessary to establish the regional antibiogram, and thereby to avoid chemoprophylaxis failure.

Shifts in the Antibiotic Susceptibility, Serogroups, and Clonal Complexes of Neisseria meningitidis in Shanghai, China: A Time Trend Analysis of the Pre-Quinolone and Quinolone Eras

BACKGROUND

Fluoroquinolones have been used broadly since the end of the 1980s and have been recommended for Neisseria meningitidis prophylaxis since 2005 in China. The aim of this study was to determine whether and how N. meningitidis antimicrobial susceptibility, serogroup prevalence, and clonal complex (CC) prevalence shifted in association with the introduction and expanding use of quinolones in Shanghai, a region with a traditionally high incidence of invasive disease due to N. meningitidis.

METHODS AND FINDINGS

A total of 374 N. meningitidis isolates collected by the Shanghai Municipal Center for Disease Control and Prevention between 1965 and 2013 were studied. Shifts in the serogroups and CCs were observed, from predominantly serogroup A CC5 (84%) in 1965-1973 to serogroup A CC1 (58%) in 1974-1985, then to serogroup C or B CC4821 (62%) in 2005-2013. The rates of ciprofloxacin nonsusceptibility in N. meningitidis disease isolates increased from 0% in 1965-1985 to 84% (31/37) in 2005-2013 (p < 0.001). Among the ciprofloxacin-nonsusceptible isolates, 87% (27/31) were assigned to either CC4821 (n = 20) or CC5 (n = 7). The two predominant ciprofloxacin-resistant clones were designated ChinaCC4821-R1-C/B and ChinaCC5-R14-A. The ChinaCC4821-R1-C/B clone acquired ciprofloxacin resistance by a point mutation, and was present in 52% (16/31) of the ciprofloxacin-nonsusceptible disease isolates. The ChinaCC5-R14-A clone acquired ciprofloxacin resistance by horizontal gene transfer, and was found in 23% (7/31) of the ciprofloxacin-nonsusceptible disease isolates. The ciprofloxacin nonsusceptibility rate was 47% (7/15) among isolates from asymptomatic carriers, and nonsusceptibility was associated with diverse multi-locus sequence typing profiles and pulsed-field gel electrophoresis patterns. As detected after 2005, ciprofloxacin-nonsusceptible strains were shared between some of the patients and their close contacts. A limitation of this study is that isolates from 1986-2004 were not available and that only a small sample of convenience isolates from 1965-1985 were available.

CONCLUSIONS

The increasing prevalence of ciprofloxacin resistance since 2005 in Shanghai was associated with the spread of hypervirulent lineages CC4821 and CC5. Two resistant meningococcal clones ChinaCC4821-R1-C/B and ChinaCC5-R14-A have emerged in Shanghai during the quinolone era. Ciprofloxacin should be utilized with caution for the chemoprophylaxis of N. meningitidis in China.