Imperial College London

ProfessorShiraneeSriskandan

Faculty of MedicineDepartment of Infectious Disease

Professor of Infectious Diseases
 
 
 
//

Contact

 

s.sriskandan

 
 
//

Assistant

 

Ms Teyanna Gaeta +44 (0)20 3313 1943

 
//

Location

 

8N21ACWBCommonwealth BuildingHammersmith Campus

//

Summary

 

Publications

Publication Type
Year
to

216 results found

Ana Vieira1 2 3, Yu Wan1 3 4, Yan Ryan5, Ho Kwong Li1 2, Rebecca L Guy4, Maria Papangeli1 2, Kristin K Huse1 2, Lucy C Reeves1 2, Valerie WC Soo1 2, Roger Daniel5, Alessandra Harley5, Karen Broughton5, Chenchal Dhami5, Mark Ganner5, Marjorie Ganner5, Zaynab Mumin5, Maryam Razaei5, Emma Rundberg5, Rufat Mammadov5, Ewurabena A Mills1 2, Vincenzo Sgro1, Kai Yi Mok1, Xavier Didelot6, Nicholas J Croucher7 8, Elita Jauneikaite3 7 8, Theresa Lamagni3 4, Colin S Brown3 4, Juliana Coelho3 4 5, Shiranee Sriskandan1 2 3, Sriskandan Set al., 2024, Rapid expansion and international spread of M1UK in the post-pandemic UK upsurge of Streptococcus pyogenes, Nature Communications, ISSN: 2041-1723

Journal article

Oswin HP, Blake E, Haddrell AE, Finn A, Sriskandan S, Reid JP, Halliday A, Goenka Aet al., 2024, An assessment of the airborne longevity of group A Streptococcus, Microbiology, Vol: 170, ISSN: 1350-0872

Group A streptococcus (GAS) infections result in more than 500 000 deaths annually. Despite mounting evidence for airborne transmission of GAS, little is known about its stability in aerosol. Measurements of GAS airborne stability were carried out using the Controlled Electrodynamic Levitation and Extraction of Bioaerosols onto a Substrate (CELEBS) instrument. CELEBS measurements with two different isolates of GAS suggest that it is aerostable, with approximately 70 % of bacteria remaining viable after 20 min of levitation at 50 % relative humidity (RH), with lower survival as RH was reduced. GAS airborne viability loss was driven primarily by desiccation and efflorescence (i.e. salt crystallization), with high pH also potentially playing a role, given reduced survival in bicarbonate containing droplet compositions. At low enough RH for efflorescence to occur, a greater proportion of organic components in the droplet appeared to protect the bacteria from efflorescence. These first insights into the aerosol stability of GAS indicate that airborne transmission of these respiratory tract bacteria may occur, and that both the composition of the droplet containing the bacteria, and the RH of the air affect the duration of bacterial survival in this environment. Future studies will explore a broader range of droplet and air compositions and include a larger selection of GAS strains.

Journal article

Zhi X, Vieira A, Huse KK, Martel PJ, Lobkowicz L, Li HK, Croucher N, Andrew I, Game L, Sriskandan Set al., 2023, Characterization of the RofA regulon in the pandemic M1global and emergent M1UK lineages of Streptococcus pyogenes, Microbial Genomics, Vol: 9, ISSN: 2057-5858

The standalone regulator RofA is a positive regulator of the pilus locus in Streptococcus pyogenes . Found in only certain emm genotypes, RofA has been reported to regulate other virulence factors, although its role in the globally dominant emm1 S. pyogenes is unclear. Given the recent emergence of a new emm1 (M1UK) toxigenic lineage that is distinguished by three non-synonymous SNPs in rofA, we characterized the rofA regulon in six emm1 strains that are representative of the two contemporary major emm1 lineages (M1global and M1UK) using RNAseq analysis, and then determined the specific role of the M1UK-specific rofA SNPs. Deletion of rofA in three M1global strains led to altered expression of 14 genes, including six non-pilus locus genes. In M1UK strains, deletion of rofA led to altered expression of 16 genes, including nine genes that were unique to M1UK. Only the pilus locus genes were common to the RofA regulons of both lineages, while transcriptomic changes varied between strains even within the same lineage. Although introduction of the three SNPs into rofA did not impact gene expression in an M1global strain, reversal of three SNPs in an M1UK strain led to an unexpected number of transcriptomic changes that in part recapitulated transcriptomic changes seen when deleting RofA in the same strain. Computational analysis predicted that interactions with a key histidine residue in the PRD domain of RofA would differ between M1UK and M1global. RofA is a positive regulator of the pilus locus in all emm1 strains but effects on other genes are strain- and lineage-specific, with no clear, common DNA binding motif. The SNPs in rofA that characterize M1UK may impact regulation of RofA; whether they alter phosphorylation of the RofA PRD domain requires further investigation.

Journal article

Pearson M, Haslam C, Fosberry A, Jones E, Reglinski M, Reeves L, Edwards RJ, Lawrenson RA, Brown JC, Mossakowska D, Pease JE, Sriskandan Set al., 2023, Structure-activity studies of Streptococcus pyogenes enzyme SpyCEP reveal high affinity for CXCL8 in the SpyCEP C-terminal, Scientific Reports, Vol: 13, ISSN: 2045-2322

The Streptococcus pyogenes cell envelope protease (SpyCEP) is vital to streptococcal pathogenesis and disease progression. Despite its strong association with invasive disease, little is known about enzymatic function beyond the ELR+ CXC chemokine substrate range. As a serine protease, SpyCEP has a catalytic triad consisting of aspartate (D151), histidine (H279), and serine (S617) residues which are all thought to be mandatory for full activity. We utilised a range of SpyCEP constructs to investigate the protein domains and catalytic residues necessary for enzyme function. We designed a high-throughput mass spectrometry assay to measure CXCL8 cleavage and applied this for the first time to study the enzyme kinetics of SpyCEP. Results revealed a remarkably low Michaelis-Menton constant (KM) of 82 nM and a turnover of 1.65 molecules per second. We found that an N-terminally-truncated SpyCEP C-terminal construct containing just the catalytic dyad of H279 and S617 was capable of cleaving CXCL8 with a similar KM of 55 nM, albeit with a reduced substrate turnover of 2.7 molecules per hour, representing a 2200-fold reduction in activity. We conclude that the SpyCEP C-terminus plays a key role in high affinity substrate recognition and binding, but that the N-terminus is required for full catalytic activity.

Journal article

McKenna S, Aylward F, Miliara X, Lau RJ, Huemer CB, Giblin SP, Huse KK, Liang M, Reeves L, Pearson M, Xu Y, Rouse SL, Pease JE, Sriskandan S, Kagawa TF, Cooney J, Matthews Set al., 2023, The protease associated (PA) domain in ScpA from Streptococcus pyogenes plays a role in substrate recruitment, BBA: Proteins and Proteomics, Vol: 1871, Pages: 1-11, ISSN: 1570-9639

Annually, over 18 million disease cases and half a million deaths worldwide are estimated to be caused by Group A Streptococcus. ScpA (or C5a peptidase) is a well characterised member of the cell enveleope protease family, which possess a S8 subtilisin-like catalytic domain and a shared multi-domain architecture. ScpA cleaves complement factors C5a and C3a, impairing the function of these critical anaphylatoxins and disrupts complement-mediated innate immunity. Although the high resolution structure of ScpA is known, the details of how it recognises its substrate are only just emerging. Previous studies have identified a distant exosite on the 2nd fibronectin domain that plays an important role in recruitment via an interaction with the substrate core. Here, using a combination of solution NMR spectroscopy, mutagenesis with functional assays and computational approaches we identify a second exosite within the protease-associated (PA) domain. We propose a model in which the PA domain assists optimal delivery of the substrate's C terminus to the active site for cleavage.

Journal article

Lamagni T, Guy RL, Sriskandan S, Decraene V, Brown CSet al., 2023, Improving maternal outcomes through early recognition, rapid notification, and investigation of invasive GAS infection, The Lancet Microbe, Vol: 4, Pages: e766-e766, ISSN: 2666-5247

Journal article

DURKIN SM, da Silva AL, Davies NWS, Sriskandan Set al., 2023, Dengue encephalopathy or encephalitis? You decide, Open Forum Infectious Diseases, Vol: 10, ISSN: 2328-8957

Awareness of neurological sequelae of dengue fever is increasing. However, as this case illustrates, there is a diagnostic conundrum in determining whether certain features are in keeping with dengue encephalopathy, or dengue encephalitis. Further consensus is required.

Journal article

Asturias EJ, Excler J-L, Ackland J, Cavaleri M, Fulurija A, Long R, McCulloch M, Sriskandan S, Sun W, Zühlke L, Kim JH, Dale JB, Steer ACet al., 2023, Safety of streptococcus pyogenes vaccines: anticipating and overcoming challenges for clinical trials and post marketing monitoring, Clinical Infectious Diseases, Vol: 77, Pages: 917-924, ISSN: 1058-4838

Streptococcus. pyogenes (Strep A) infections result in a vastly underestimated burden of acute and chronic disease globally. The Strep A Vaccine Global Consortium (SAVAC) mission is to accelerate the development of safe, effective and affordable S. pyogenes vaccines. The safety of vaccine recipients is of paramount importance. A single S. pyogenes vaccine clinical trial conducted in the 1960s raised important safety concerns. A SAVAC Safety Working Group was established to review the safety assessment methodology and results of more recent early phase clinical trials and to consider future challenges for vaccine safety assessments across all phases of vaccine development. No clinical or biological safety signals were detected in any of these early phase trials in the modern era. Improvements in vaccine safety assessments need further consideration, particularly for pediatric clinical trials, large-scale efficacy trials, and preparation for post-marketing pharmacovigilance.

Journal article

Wan Y, Sabnis A, Mumin Z, Potterill I, Jauneikaite E, Brown CS, Ellington MJ, Edwards A, Sriskandan Set al., 2023, IS1-related large-scale deletion of chromosomal regions harbouring the oxygen-insensitive nitroreductase gene nfsB causes nitrofurantoin heteroresistance in Escherichia coli, Microbial Genomics, Vol: 9, Pages: 1-11, ISSN: 2057-5858

Nitrofurantoin is a broad-spectrum first-line antimicrobial used for managing uncomplicated urinary tract infection (UTI). Loss-of-function mutations in chromosomal genes nfsA, nfsB and ribE of Escherichia coli are known to reduce nitrofurantoin susceptibility. Here, we report the discovery of nitrofurantoin heteroresistance in E. coli clinical isolates and a novel genetic mechanism associated with this phenomenon. Subpopulations with lower nitrofurantoin susceptibility than major populations (hereafter, nitrofurantoin-resistant subpopulations) in two E. coli blood isolates (previously whole-genome sequenced) were identified using population analysis profiling. Each isolate was known to have a loss-of-function mutation in nfsA. From each isolate, four nitrofurantoin-resistant isolates were derived at a nitrofurantoin concentration of 32 mg l-1, and a comparator isolate was obtained without any nitrofurantoin exposure. Genomes of derived isolates were sequenced on Illumina and Nanopore MinION systems. Genetic variation between isolates was determined based on genome assemblies and read mapping. Nitrofurantoin minimum inhibitory concentrations (MICs) of both blood isolates were 64 mg l-1, with MICs of major nitrofurantoin-susceptible populations varying from 4 to 8 mg l-1. Two to 99 c.f.u. per million demonstrated growth at the nitrofurantoin concentration of 32 mg l-1, which is distinct from that of a homogeneously susceptible or resistant isolate. Derived nitrofurantoin-resistant isolates had 11-66 kb deletions in chromosomal regions harbouring nfsB, and all deletions were immediately adjacent to IS1-family insertion sequences. Our findings demonstrate that the IS1-associated large-scale genetic deletion is a hitherto unrecognized mechanism of nitrofurantoin heteroresistance and could compromise UTI management. Further, frequencies of resistant subpopulations from nitrofurantoin-heteroresistant isolates may cha

Journal article

Zhi X, Li HK, Li H, Loboda Z, Charles S, Vieira A, Huse K, Jauneikaite E, Reeves L, Mok KY, Coelho J, Lamagni T, Sriskandan Set al., 2023, Emerging invasive group A Streptococcus M1UK lineage detected by allele-specific PCR, England, 2020, Emerging Infectious Diseases, Vol: 29, Pages: 1007-1010, ISSN: 1080-6040

Increasing reports of invasive Streptococcus pyogenes infections mandate surveillance for toxigenic lineage M1UK. An allele-specific PCR was developed to distinguish M1UK from other emm1 strains. The M1UK lineage represented 91% of invasive emm1 isolates in England in 2020. Allele-specific PCR will permit surveillance for M1UK without need for genome sequencing.

Journal article

McGuire E, Li A, Collin S, Decraene V, Cook M, Padfield S, Sriskandan S, van Beneden C, Lamagni T, Brown CSet al., 2023, Time to negative throat culture following initiation of antibiotics for pharyngeal group A Streptococcus: a systematic review and meta-analysis up to October 2021 to inform public health control measures, Eurosurveillance, Vol: 28, Pages: 1-19, ISSN: 1025-496X

Background: Public health guidance recommending isolation of individuals with group A streptococcal (GAS) infection or carriage for 12–24 h from antibiotic initiation to prevent onward transmission requires a strong evidence base.Aim: To estimate the pooled proportion of individuals who remain GAS culture-positive at set intervals after initiation of antibiotics through a systematic literature review (PROSPERO CRD42021290364) and meta-analysis.Methods: We searched Ovid MEDLINE (1946–), EMBASE (1974–) and Cochrane library. We included interventional or observational studies with ≥ 10 participants reporting rates of GAS throat culture positivity during antibiotic treatment for culture-confirmed GAS pharyngitis, scarlet fever and asymptomatic pharyngeal GAS carriage. We did not apply age, language or geographical restrictions.Results: Of 5,058 unique records, 43 were included (37 randomised controlled studies, three non-randomised controlled trials and three before-and-after studies). The proportion of individuals remaining culture-positive on day 1, day 2 and days 3–9 were 6.9% (95% CI: 2.7–16.8%), 5.4% (95% CI: 2.1–13.3%) and 2.6% (95% CI: 1.6–4.2%). For penicillins and cephalosporins, day 1 positivity was 6.5% (95% CI: 2.5–16.1%) and 1.6% (95% CI: 0.04–42.9%), respectively. Overall, for 9.1% (95% CI: 7.3–11.3), throat swabs collected after completion of therapy were GAS culture-positive. Only six studies had low risk of bias.Conclusions: Our review provides evidence that antibiotics for pharyngeal GAS achieve a high rate of culture conversion within 24 h but highlights the need for further research given methodological limitations of published studies and imprecision of pooled estimates. Further evidence is needed for non-beta-lactam antibiotics and asymptomatic individuals.

Journal article

Li H-K, Zhi X, Vieira A, Whitwell HJ, Schricker A, Jauneikaite E, Li H, Yosef A, Andrew I, Game L, Turner CE, Lamagni T, Coelho J, Sriskandan Set al., 2023, Characterisation of emergent toxigenic M1UK Streptococcus pyogenes and associated sublineages, Microbial Genomics, Vol: 9, Pages: 1-15, ISSN: 2057-5858

Streptococcus pyogenes genotype emm1 is a successful, globally distributed epidemic clone that is regarded as inherently virulent. An emm1 sublineage, M1UK, that produces increased levels of SpeA toxin was associated with increased scarlet fever and invasive infections in England in 2015/2016. Defined by 27 SNPs in the core genome, M1UK is now dominant in England. To more fully characterize M1UK, we undertook comparative transcriptomic and proteomic analyses of M1UK and contemporary non-M1UKemm1 strains (M1global). Just seven genes were differentially expressed by M1UK compared with contemporary M1global strains. In addition to speA, five genes in the operon that includes glycerol dehydrogenase were upregulated in M1UK (gldA, mipB/talC, pflD, and phosphotransferase system IIC and IIB components), while aquaporin (glpF2) was downregulated. M1UK strains have a stop codon in gldA. Deletion of gldA in M1global abrogated glycerol dehydrogenase activity, and recapitulated upregulation of gene expression within the operon that includes gldA, consistent with a feedback effect. Phylogenetic analysis identified two intermediate emm1 sublineages in England comprising 13/27 (M113SNPs) and 23/27 SNPs (M123SNPs), respectively, that had failed to expand in the population. Proteomic analysis of invasive strains from the four phylogenetic emm1 groups highlighted sublineage-specific changes in carbohydrate metabolism, protein synthesis and protein processing; upregulation of SpeA was not observed in chemically defined medium. In rich broth, however, expression of SpeA was upregulated ~10-fold in both M123SNPs and M1UK sublineages, compared with M113SNPs and M1global. We conclude that stepwise accumulation of SNPs led to the emergence of M1UK. While increased expression of SpeA is a key indicator of M1UK and undoubtedly important, M1UK strains have outcompeted M123SNPs and other emm types that produce similar or more superantigen toxin. We speculate that an accumulation of adaptive SN

Journal article

Camille H, Tomas U, Romain B, Parks T, Sriskandan S, De Prost N, Chosidow Oet al., 2023, Necrotising soft tissue infections, The Lancet Infectious Diseases, Vol: 23, Pages: e81-e94, ISSN: 1473-3099

The incidence of necrotising soft tissue infections (NSTI) has increased during recent decades such that most physicians might see at least one case of these potentially life-threatening infections in their career. Despite advances in care, NSTI are still associated with high morbidity and mortality, underlining a need for continued education of the medical community. In particular, failure to suspect NSTI fueled by poor awareness of the disease promotes delays to first surgical debridement, amplifying disease severity and adverse outcomes. This review will focus on practical approaches to management of NSTI including prompt recognition, initiation of specific management, exploratory surgery, and aftercare. Increased alertness and awareness for NSTI should improve time to diagnosis and early referral to specialised centers, with consequent improvement in NSTI prognosis.

Journal article

Otter JA, Zhou J, Price JR, Reeves L, Zhu N, Randell P, Sriskandan S, Barclay WS, Holmes AHet al., 2023, SARS-CoV-2 surface and air contamination in an acute healthcare setting during the first and second pandemic waves, Journal of Hospital Infection, Vol: 132, Pages: 36-45, ISSN: 0195-6701

BackgroundSurfaces and air in healthcare facilities can be contaminated with severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2). Previously, the authors identified SARS-CoV-2 RNA on surfaces and air in their hospital during the first wave of the coronavirus disease 2019 pandemic (April 2020).AimTo explore whether the profile of SARS-CoV-2 surface and air contamination had changed between April 2020 and January 2021.MethodsThis was a prospective, cross-sectional, observational study in a multi-site London hospital. In January 2021, surface and air samples were collected from comparable areas to those sampled in April 2020, comprising six clinical areas and a public area. SARS-CoV-2 was detected using reverse transcription polymerase chain reaction and viral culture. Sampling was also undertaken in two wards with natural ventilation alone. The ability of the prevalent variants at the time of the study to survive on dry surfaces was evaluated.FindingsNo viable virus was recovered from surfaces or air. Five percent (N=14) of 270 surface samples and 4% (N=1) of 27 air samples were positive for SARS-CoV-2, which was significantly lower than in April 2020 [52% (N=114) of 218 surface samples and 48% (N=13) of 27 air samples (P<0.001, Fisher's exact test)]. There was no clear difference in the proportion of surface and air samples positive for SARS-CoV-2 RNA based on the type of ventilation in the ward. All variants tested survived on dry surfaces for >72 h, with a <3-log10 reduction in viable count.ConclusionThis study suggests that enhanced infection prevention measures have reduced the burden of SARS-CoV-2 RNA on surfaces and air in healthcare facilities.

Journal article

Frost H, Jean-Louis E, Sriskandan S, Alma Fet al., 2023, Correlates of immunity to Group A Streptococcus: a pathway to vaccine development, npj Vaccines, Vol: 8, ISSN: 2059-0105

Understanding immunity in humans to Group A Streptococcus (Strep A) is critical for the development of successful vaccines to prevent the morbidity and mortality attributed to Strep A infections. Despite decades of effort, no licensed vaccine against Strep A exists and immune correlates of protection are lacking; a major impediment to vaccine development. In the absence of a vaccine, we can take cues from the development of natural immunity to Strep A in humans to identify immune correlates of protection. The age stratification of incidence of acute Strep A infections, peaking in young children and waning in early adulthood, coincides with the development of specific immune responses. Therefore, understanding the immune mechanisms involved in natural protection from acute Strep A infection is critical to identifying immune correlates to inform vaccine development. This perspective summarises the findings from natural infection studies, existing assays of immunity to Strep A, and highlights the gaps in knowledge to guide the development of Strep A vaccines and associated correlates of protection.

Journal article

Vieira A, Soo VWC, Li HK, Zhi X, Reeves L, Huse K, Mok KY, Cowen O, Jauneikaite E, Coelho J, Sriskandan Set al., 2023, Tricontinental detection of Streptococcus pyogenes M1<sub>UK</sub>: A call for wider research and active surveillance

<h4>Summary</h4> The Streptococcus pyogenes M1 UK lineage, characterised by an intrinsic ability to express SpeA toxin and defined by 27 single nucleotide polymorphisms in the core genome, dominates the population of emm 1 S. pyogenes isolates in England. The lineage has been identified elsewhere in Europe, North America, and, most recently, Australia. SpeA however may not be the sole deterministic factor underlying success of the M1 UK lineage. Production of SpeA by strains belonging to an intermediate emm 1 sublineage, M1 23SNP , is indistinguishable from M1 UK strains. Despite this, in England at least, M1 UK has outcompeted strains from the M1 23SNP sublineage. We infer that the fitness of M1 UK resides in additional properties that confer an advantage to S. pyogenes , underlining a need for further research. A single nucleotide polymorphism (SNP) in the ssrA leader sequence upstream of speA is one of a limited number of SNPs that distinguish intermediate sublineages that differ in SpeA production. Introduction of the ssrA SNP into representative isolates of the widely disseminated M1 global clone and the intermediate M1 13SNP lineage (that cannot otherwise produce readily-detectable SpeA in culture) resulted in SpeA expression, confirming the importance of the ssrA SNP to SpeA phenotype. However, RNAseq analysis of clinical strains showed that presence of the SNP was not invariably linked to read-through from the ssrA leader sequence or SpeA expression. Literature review suggests that read through and speA mRNA transcript length may be impacted by the two component regulator CovRS, pointing to a complex regulatory network interaction between the bacterial chromosome and phage-encoded superantigens.

Working paper

Li HK, Zhi X, Vieira A, Whitwell HJ, Schricker A, Jauneikaite E, Li H, Yosef A, Andrew I, Game L, Turner CE, Lamagni T, Coelho J, Sriskandan Set al., 2022, Characterisation of emergent toxigenic M1<sub>UK</sub><i>Streptococcus pyogenes</i>and associated sublineages

<jats:title>Abstract</jats:title><jats:p><jats:italic>Emm</jats:italic>1<jats:italic>Streptococcus pyogenes</jats:italic>is a successful, globally-distributed epidemic clone that is regarded as inherently invasive. An<jats:italic>emm</jats:italic>1 sublineage, M1<jats:sub>UK</jats:sub>, that expresses increased SpeA toxin, was associated with increased scarlet fever and invasive infections in England in 2015/2016. Defined by 27 SNPs in the core genome, M1<jats:sub>UK</jats:sub>is now dominant in England. To more fully characterise M1<jats:sub>UK</jats:sub>, we undertook comparative transcriptomic and proteomic analyses of M1<jats:sub>UK</jats:sub>and contemporary non-M1<jats:sub>UK</jats:sub><jats:italic>emm</jats:italic>1 strains (M1<jats:sub>global</jats:sub>).</jats:p><jats:p>Just seven genes were differentially expressed by M1<jats:sub>UK</jats:sub>compared with contemporary M1<jats:sub>global</jats:sub>strains. In addition to speA, five genes in the operon that includes glycerol dehydrogenase were upregulated in M1<jats:sub>UK</jats:sub>(gldA, mipB/talC, pflD, and pts system IIC and IIB components), while aquaporin (glpF2) was downregulated. M1<jats:sub>UK</jats:sub>strains have a stop codon in gldA. Deletion of the gldA gene in M1<jats:sub>global</jats:sub>abrogated glycerol dehydrogenase activity, and recapitulated upregulation of gene expression within the operon that includes gldA, consistent with a feedback effect.</jats:p><jats:p>Phylogenetic analysis identified two intermediate<jats:italic>emm</jats:italic>1 sublineages in England comprising 13/27 (M1<jats:sub>13SNPs</jats:sub>) and 23/27 SNPs (M1<jats:sub>23SNPs</jats:sub>) respectively, that had failed to expand in the population. Proteomic analysis

Working paper

Zhi X, Li HK, Li H, Loboda Z, Charles S, Vieira A, Huse K, Jauneikaite E, Coelho J, Lamagni T, Sriskandan Set al., 2022, Ongoing emergence of M1<sub>UK</sub>lineage among invasive group A streptococcus isolates in 2020 and use of allele-specific PCR

<jats:title>Summary</jats:title><jats:sec><jats:title>Background</jats:title><jats:p>An increasing burden of invasive group A streptococcal infections is reported in multiple countries, notably England, where scarlet fever cases are also abundant. In England, increased scarlet fever and invasive infections have been associated with emergence of a sublineage of<jats:italic>emm</jats:italic>1<jats:italic>Streptococcus pyogenes</jats:italic>that expresses increased SpeA scarlet fever erythrogenic toxin. Wider surveillance for toxigenic<jats:italic>Streptococcus pyogenes</jats:italic>lineage M1<jats:sub>UK</jats:sub>is much needed however, to date, lineage assignment has required genome sequencing limiting surveillance to those centres with access to such facilities.</jats:p></jats:sec><jats:sec><jats:title>Methods</jats:title><jats:p>To circumvent the requirement for genome sequencing, an allele-specific PCR was developed to distinguish M1<jats:sub>UK</jats:sub>from other<jats:italic>emm</jats:italic>1 strains. Additional PCR assays were developed to distinguish M1<jats:sub>UK</jats:sub>from two intermediate lineages that were detected previously. The assay was evaluated using DNA from genome-sequenced upper respiratory tract<jats:italic>emm</jats:italic>1<jats:italic>S. pyogenes</jats:italic>strains and a further set of 16 genome-sequenced invasive<jats:italic>S. pyogenes</jats:italic>isolates that included the two intermediate lineages. The assay was then applied to DNA from all 305 invasive<jats:italic>emm</jats:italic>1 isolates that had been submitted to the reference laboratory in the one pear period Jan 1-Dec 31 2020, in order to assign lineage.</jats:p></jats:sec><jats:sec><jats:title>Results</jats:title><jats:p>The allele sp

Journal article

Cordery R, Reeves L, Zhou J, Rowan A, Watber P, Rosadas C, Crone M, Storch M, Freemont P, Mosscrop L, Cowley A, Zelent G, Bisset K, Le Blond H, Regmi S, Buckingham C, Junaideen R, Abdulla N, Eliahoo J, Mindlin M, Lamagni T, Barclay W, Taylor GP, Sriskandan Set al., 2022, Transmission of SARS-CoV-2 by children to contacts in schools and households: a prospective cohort and environmental sampling study in London, The Lancet Microbe, Vol: 3, Pages: e814-e823, ISSN: 2666-5247

Background: Assessing transmission of SARS-CoV-2 by children in schools is of critical importance to inform public health action. We assessed frequency of acquisition of SARS-CoV-2 by contacts of pupils with COVID-19 in schools and households, and quantified SARS-CoV-2 shed into air and onto fomites in both settings.Methods: Incidents involving exposure to at least one index pupil with COVID-19 in 8 schools were identified between October 2020-July 2021 (prevailing variants, original, alpha and delta). Weekly PCR testing for SARS-CoV-2 was undertaken on immediate classroom contacts (the “bubble”), non-bubble school contacts, and household contacts of index pupils, supported by genome sequencing, and on surface and air samples from school and home environments.Findings: Secondary transmission of SARS-CoV-2 was not detected in 28 bubble contacts, representing 10 bubble classes (participation rate 8.8%, IQR 4.6-15.3%). Across 8 non-bubble classes, 3/62 pupils tested positive but these were unrelated to the original index case (participation rate 22.5%, IQR 9.7-32.3%). All three were asymptomatic and tested positive in one setting on the same day. In contrast, secondary transmission to previously-negative household contacts from infected index pupils was 17.1% (6/35) rising to 27.7% (13/47) when considering all potentialinfections in household contacts. Environmental contamination with SARS-CoV-2 was rare in schools; fomite SARS-CoV-2 was identified in 4/189 (2.1%) samples in bubble classrooms, 2/127 (1.6%) samples in non-bubble classrooms, and 5/130 (3.8%) samples in washrooms. This contrasted with fomites in households, where SARS-CoV-2 was identified in 60/248 (24.2%) bedroom samples, 66/241 (27.4%) communal room samples, and 21/188 (11.2%) bathroom samples. Air sampling identified SARS-CoV-2 RNA in just 1/68 (1.5%) of school air samples, compared with 21/85 (24.7%) of air samples taken in homes.Interpretation: There was no evidence of large scale SARS-Co

Journal article

Cordery R, Purba A, Begum L, Mills E, Mosavie M, Vieira A, Jauneikaite E, Leung RCY, Siggins M, Ready D, Hoffman P, Lamagni T, Sriskandan Set al., 2022, Frequency of transmission, asymptomatic shedding, and airborne spread of Streptococcus pyogenes in schoolchildren exposed to scarlet fever: a prospective, longitudinal, multicohort, molecular epidemiological, contact-tracing study in England, UK, The Lancet Microbe, Vol: 3, Pages: e366-e375, ISSN: 2666-5247

BackgroundDespite recommendations regarding prompt treatment of cases and enhanced hygiene measures, scarlet fever outbreaks increased in England between 2014 and 2018. We aimed to assess the effects of standard interventions on transmission of Streptococcus pyogenes to classroom contacts, households, and classroom environments to inform future guidance.MethodsWe did a prospective, longitudinal, multicohort, molecular epidemiological, contact-tracing study in six settings across five schools in Greater London, UK. Schools and nurseries were eligible to participate if they had reported two cases of scarlet fever within 10 days of each other among children aged 2–8 years from the same class, with the most recent case arising in the preceding 48 h. We cultured throat swabs from children with scarlet fever, classroom contacts, and household contacts at four timepoints. We also cultured hand swabs and cough plates from all cases in years 1 and 2 of the study, and from classroom contacts in year 2. Surface swabs from toys and other fomites in classrooms were cultured in year 1, and settle plates from classrooms were collected in year 2. Any sample with S pyogenes detected was recorded as positive and underwent emm genotyping and genome sequencing to compare with the outbreak strain.FindingsSix classes, comprising 12 cases of scarlet fever, 17 household contacts, and 278 classroom contacts were recruited between March 1 and May 31, 2018 (year 1), and between March 1 and May 31, 2019 (year 2). Asymptomatic throat carriage of the outbreak strains increased from 11 (10%) of 115 swabbed children in week 1, to 34 (27%) of 126 in week 2, to 26 (24%) of 108 in week 3, and then five (14%) of 35 in week 4. Compared with carriage of outbreak S pyogenes strains, colonisation with non-outbreak and non-genotyped S pyogenes strains occurred in two (2%) of 115 swabbed children in week 1, five (4%) of 126 in week 2, six (6%) of 108 in week 3, and in none of the 35 children in week 4

Journal article

Taylor E, Jauneikaite E, Sriskandan S, Woodford N, Hopkins KLet al., 2022, Novel 16S rRNA methyltransferase RmtE3 in acinetobacter baumannii ST79., Journal of Medical Microbiology, Vol: 71, ISSN: 0022-2615

Introduction. The 16S rRNA methyltransferase (16S RMTase) gene armA is the most common mechanism conferring high-level aminoglycoside resistance in Acinetobacter baumannii, although rmtA, rmtB, rmtC, rmtD and rmtE have also been reported.Hypothesis/Gap statement. The occurrence of 16S RMTase genes in A. baumannii in the UK and Republic of Ireland is currently unknown.Aim. To identify the occurrence of 16S RMTase genes in A. baumannii isolates from the UK and the Republic of Ireland between 2004 and 2015.Methodology. Five hundred and fifty pan-aminoglycoside-resistant A. baumannii isolates isolated from the UK and the Republic of Ireland between 2004 and 2015 were screened by PCR to detect known 16S RMTase genes, and then whole-genome sequencing was conducted to screen for novel 16S RMTase genes.Results. A total of 96.5 % (531/550) of isolates were positive for 16S RMTase genes, with all but 1 harbouring armA (99.8 %, 530/531). The remaining isolates harboured rmtE3, a new rmtE variant. Most (89.2 %, 473/530) armA-positive isolates belonged to international clone II (ST2), and the rmtE3-positive isolate belonged to ST79. rmtE3 shared a similar genetic environment to rmtE2 but lacked an ISCR20 element found upstream of rmtE2.Conclusion. This is the first report of rmtE in A. baumannii in Europe; the potential for transmission of rmtE3 to other bacterial species requires further research.

Journal article

Seethalakshmi PS, Charity OJ, Giakoumis T, Kiran GS, Sriskandan S, Voulvoulis N, Selvin Jet al., 2022, Delineating the impact of COVID-19 on antimicrobial resistance: An Indian perspective, Science of the Total Environment, Vol: 818, ISSN: 0048-9697

The COVID-19 pandemic has shattered millions of lives globally and continues to be a challenge to public health due to the emergence of variants of concern. Fear of secondary infections following COVID-19 has led to an escalation in antimicrobial use during the pandemic, while some antimicrobials have been repurposed as treatments for SARS-CoV-2, further driving antimicrobial resistance. India is one of the largest producers and consumers of antimicrobials globally, hence the task of curbing antimicrobial resistance is a huge challenge. Practices like empirical antimicrobial prescription and repurposing of drugs in clinical settings, self-medication and excessive use of antimicrobial hygiene products may have negatively impacted the prevalence of antimicrobial resistance in India. However, the expanded production of antimicrobials and disinfectants during the pandemic in response to increased demand may have had an even greater impact on the threat of antimicrobial resistance through major impacts on the environment. The review provides an outline of the impact COVID-19 can have on antimicrobial resistance in clinical settings and the possible outcomes on the environment. This review calls for the upgrading of existing antimicrobial policies and emphasizes the need for research studies to understand the impact of the pandemic on antimicrobial resistance in India.

Journal article

McKenna S, Huse KK, Giblin S, Pearson M, Majid Al Shibar MS, Sriskandan S, Matthews S, Pease JEet al., 2022, The role of streptococcal cell-envelope proteases in bacterial evasion of the innate immune system, Journal of Innate Immunity, Vol: 14, Pages: 69-88, ISSN: 1662-811X

Bacteria possess the ability to evolve varied and ingenious strategies to outwit the host immune system, instigating an evolutionary arms race. Proteases are amongst the many weapons employed by bacteria, which specifically cleave and neutralize key signalling molecules required for a coordinated immune response. In this article, we focus on a family of S8 subtilisin-like serine proteases expressed as cell-envelope proteases (CEPs) by group A and group B streptococci. Two of these proteases known as Streptococcus pyogenes CEP (SpyCEP) and C5a peptidase cleave the chemokine CXCL8 and the complement fragment C5a, respectively. Both CXCL8 and C5a are potent neutrophil-recruiting chemokines, and by neutralizing their activity, streptococci evade a key defence mechanism of innate immunity. We review the mechanisms by which CXCL8 and C5a recruit neutrophils and the characterization of SpyCEP and C5a peptidase, including both in vitro and in vivo studies. Recently described structural insights into the function of this CEP family are also discussed. We conclude by examining the progress of prototypic vaccines incorporating SpyCEP and C5a peptidase in their preparation. Since streptococci-producing SpyCEP and C5a peptidase are responsible for a considerable global disease burden, targeting these proteases by vaccination strategies or by small-molecule antagonists should provide protection from and promote the resolution of streptococcal infections.

Journal article

Mehta R, Chekmeneva E, Jackson H, Sands C, Mills E, Arancon D, Li HK, Arkell P, Rawson T, Hammond R, Amran M, Haber A, Cooke G, Noursadeghi M, Kaforou M, Lewis M, Takats Z, Sriskandan Set al., 2022, Antiviral metabolite 3’-Deoxy-3’,4’-didehydro-cytidine is detectable in serum and identifies acute viral infections including COVID-19, Med, Vol: 3, Pages: 204-215.e6, ISSN: 2666-6340

Background:There is a critical need for rapid viral infection diagnostics to enable prompt case identification in pandemic settings and support targeted antimicrobial prescribing.Methods:Using untargeted high-resolution liquid chromatography coupled with mass spectrometry, we compared the admission serum metabolome of emergency department patients with viral infections including COVID-19, bacterial infections, inflammatory conditions, and healthy controls. Sera from an independent cohort of emergency department patients admitted with viral or bacterial infections underwent profiling to validate findings. Associations between whole-blood gene expression and the identified metabolite of interest were examined.Findings:3'-Deoxy-3',4'-didehydro-cytidine (ddhC), a free base of the only known human antiviral small molecule ddhC-triphosphate (ddhCTP), was detected for the first time in serum. When comparing 60 viral to 101 non-viral cases in the discovery cohort, ddhC was the most differentially abundant metabolite, generating an area under the receiver operating characteristic curve (AUC) of 0.954 (95% CI: 0.923-0.986). In the validation cohort, ddhC was again the most significantly differentially abundant metabolite when comparing 40 viral to 40 bacterial cases, generating an AUC of 0.81 (95% CI 0.708-0.915). Transcripts of viperin and CMPK2, enzymes responsible for ddhCTP synthesis, were amongst the five genes most highly correlated to ddhC abundance.Conclusions:The antiviral precursor molecule ddhC is detectable in serum and an accurate marker for acute viral infection. Interferon-inducible genes viperin and CMPK2 are implicated in ddhC production in vivo. These findings highlight a future diagnostic role for ddhC in viral diagnosis, pandemic preparedness, and acute infection management.

Journal article

Taylor E, Jauneikaite E, Sriskandan S, Woodford N, Hopkins Ket al., 2022, Detection and characterisation of 16S rRNA methyltransferase-producing Pseudomonas aeruginosa from the UK and Republic of Ireland from 2003-2015, International Journal of Antimicrobial Agents, Vol: 59, ISSN: 0924-8579

16S rRNA methyltransferase (16S RMTase) genes confer high-level aminoglycoside resistance, reducing treatment options for multidrug-resistant Gram-negative bacteria. Pseudomonas aeruginosa isolates (n = 221) exhibiting high-level pan-aminoglycoside resistance (amikacin, gentamicin and tobramycin MICs ≥64, ≥32 and ≥32 mg/L, respectively) were screened for 16S RMTase genes to determine their occurrence among isolates submitted to a national reference laboratory from December 2003 to December 2015. 16S RMTase genes were identified using two multiplex PCRs, and whole-genome sequencing (WGS) was used to identify other antibiotic resistance genes, sequence types (STs) and the genetic environment of 16S RMTase genes. 16S RMTase genes were found in 8.6% (19/221) of isolates, with rmtB4 (47.4%; 9/19) being most common, followed by rmtD3 (21.1%; 4/19), rmtF2 (15.8%; 3/19) and single isolates harbouring rmtB1, rmtC and rmtD1. Carbapenemase genes were found in 89.5% (17/19) of 16S RMTase-positive isolates, with blaVIM (52.9%; 9/17) being most common. 16S RMTase genes were found in ‘high-risk’ clones known to harbour carbapenemase genes (ST233, ST277, ST357, ST654 and ST773). Analysis of the genetic environment of 16S RMTase genes identified that IS6100 was genetically linked to rmtB1; IS91 to rmtB4, rmtC or rmtD3; ISCR14 to rmtD1; and rmtF2 was linked to Tn3, IS91 or Tn1721. Although 16S RMTase genes explained only 8.6% of pan-aminoglycoside resistance in the P. aeruginosa isolates studied, the association of 16S RMTase genes with carbapenemase-producers and ‘high-risk’ clones highlights that continued surveillance is required to monitor spread as well as the importance of suppressing the emergence of dually-resistant clones in hospital settings.

Journal article

Herdman MT, Cordery R, Karo B, Purba AK, Begum L, Lamagni T, Kee C, Balasegaram S, Sriskandan Set al., 2021, Clinical management and impact of scarlet fever in the modern era: findings from a cross-sectional study of cases in London, 2018-2019, BMJ Open, Vol: 12, Pages: 1-9, ISSN: 2044-6055

Objectives In response to increasing incidence of scarlet fever and wider outbreaks of group A streptococcal infections in London, we aimed to characterise the epidemiology, symptoms, management and consequences of scarlet fever, and to identify factors associated with delayed diagnosis.Design and setting Cross-sectional community-based study of children with scarlet fever notified to London’s three Health Protection Teams, 2018–2019.Participants From 2575 directly invited notified cases plus invitations via parental networks at 410 schools/nurseries with notified outbreaks of confirmed/probable scarlet fever, we received 477 responses (19% of those directly invited), of which 412 met the case definition. Median age was 4 years (range <1 to 16), 48% were female, and 70% were of white ethnicity.Outcome measures Preplanned measures included quantitative description of case demographics, symptoms, care-seeking, and clinical, social, and economic impact on cases and households. After survey completion, secondary analyses of factors associated with delayed diagnosis (by logistic regression) and consequences of delayed diagnosis (by Cox’s regression), and qualitative analysis of free text comments were added.Results Rash was reported for 89% of cases, but followed onset of other symptoms for 71%, with a median 1-day delay. Pattern of onset varied with age: sore throat was more common at onset among children 5 years and older (OR3.1, 95% CI 1.9 to 5.0). At first consultation, for 28%, scarlet fever was not considered: in these cases, symptoms were frequently attributed to viral infection (60%, 64/106). Delay in diagnosis beyond first consultation occurred more frequently among children aged 5+ who presented with sore throat (OR 2.8 vs 5+without sore throat; 95% CI 1.3 to 5.8). Cases with delayed diagnosis took, on average, 1 day longer to return to baseline activities.Conclusions Scarlet fever may be initially overlooked, es

Journal article

Siggins MK, Sriskandan S, 2021, Bacterial lymphatic metastasis in infection and immunity, Cells, Vol: 11, ISSN: 2073-4409

Lymphatic vessels permeate tissues around the body, returning fluid from interstitial spaces back to the blood after passage through the lymph nodes, which are important sites for adaptive responses to all types of pathogens. Involvement of the lymphatics in the pathogenesis of bacterial infections is not well studied. Despite offering an obvious conduit for pathogen spread, the lymphatic system has long been regarded to bar the onward progression of most bacteria. There is little direct data on live virulent bacteria, instead understanding is largely inferred from studies investigating immune responses to viruses or antigens in lymph nodes. Recently, we have demonstrated that extracellular bacterial lymphatic metastasis of virulent strains of Streptococcus pyogenes drives systemic infection. Accordingly, it is timely to reconsider the role of lymph nodes as absolute barriers to bacterial dissemination in the lymphatics. Here, we summarise the routes and mechanisms by which an increasing variety of bacteria are acknowledged to transit through the lymphatic system, including those that do not necessarily require internalisation by host cells. We discuss the anatomy of the lymphatics and other factors that influence bacterial dissemination, as well as the consequences of underappreciated bacterial lymphatic metastasis on disease and immunity.

Journal article

Wan Y, Mills E, Leung RCY, Vieira A, Zhi X, Croucher NJ, Woodford N, Jauneikaite E, Ellington MJ, Sriskandan Set al., 2021, Alterations in chromosomal genes nfsA, nfsB, and ribE are associated with nitrofurantoin resistance in escherichia coli from the UK, Microbial Genomics, Vol: 7, Pages: 1-19, ISSN: 2057-5858

Antimicrobial resistance in enteric or urinary Escherichia coli is a risk factor for invasive E. coli infections. Due to widespread trimethoprim resistance amongst urinary E. coli and increased bacteraemia incidence, a national recommendation to prescribe nitrofurantoin for uncomplicated urinary tract infection was made in 2014. Nitrofurantoin resistance is reported in <6% urinary E. coli isolates in the UK, however, mechanisms underpinning nitrofurantoin resistance in these isolates remain unknown. This study aimed to identify the genetic basis of nitrofurantoin resistance in urinary E. coli isolates collected from north west London and then elucidate resistance-associated genetic alterations in available UK E. coli genomes. As a result, an algorithm was developed to predict nitrofurantoin susceptibility.Deleterious mutations and gene-inactivating insertion sequences in chromosomal nitroreductase genes nfsA and/or nfsB were identified in genomes of nine nitrofurantoin-resistant urinary E. coli isolates, as well as all further 11 E. coli isolates that were experimentally validated to be nitrofurantoin resistant. Eight categories of allelic changes in nfsA, nfsB, and the associated gene ribE were detected in 12,412 E. coli genomes from the UK. Evolutionary analysis of these three genes revealed homoplasic mutations and explained the previously reported order of stepwise mutations. The mobile gene complex oqxAB, which is associated with reduced nitrofurantoin susceptibility, was identified in only one of the 12,412 genomes.In conclusion, mutations and insertion sequences in nfsA and nfsB were leading causes of nitrofurantoin resistance in UK E. coli. As nitrofurantoin exposure increases in human populations, the prevalence of nitrofurantoin resistance in carriage E. coli isolates and those from urinary and bloodstream infections should be monitored.

Journal article

Pearson M, Haslam C, Fosberry A, Jones EJ, Reglinski M, Edwards RJ, Lawrenson RA, Brown JC, Mossakowska D, Pease JE, Sriskandan Set al., 2021, Structure-activity studies of<i>Streptococcus pyogenes</i>enzyme SpyCEP reveal high affinity for CXCL8 in the SpyCEP C-terminal

<jats:title>Abstract</jats:title><jats:p>The<jats:italic>Streptococcus pyogenes</jats:italic>cell envelope protease (SpyCEP) is vital to streptococcal pathogenesis and disease progression. Despite its strong association with invasive disease, little is known about enzymatic function beyond the ELR<jats:sup>+</jats:sup>CXC chemokine substrate range. As a serine protease, SpyCEP has a catalytic triad consisting of aspartate (D151), histidine (H279), and serine (S617) residues which are all thought to be mandatory for full activity. We utilised a range of SpyCEP constructs to investigate the protein domains and catalytic residues necessary for enzyme function. We designed a high-throughput mass spectrometry assay to measure CXCL8 cleavage and applied this for the first time to study the enzyme kinetics of SpyCEP.</jats:p><jats:p>Results revealed a remarkably low Michaelis-Menton constant (K<jats:sub>M</jats:sub>) of 82 nM and a turnover of 1.65 molecules per second. We found that an N-terminally-truncated SpyCEP C-terminal construct containing just the catalytic dyad of H279 and S617 was capable of cleaving CXCL8 with a similar K<jats:sub>M</jats:sub>of 55 nM, albeit with a reduced substrate turnover of 2.7 molecules per hour, representing a 2,200- fold reduction in activity. We conclude that the SpyCEP C-terminus plays a key role in high affinity substrate recognition and binding, but that the N-terminus is required for full catalytic activity.</jats:p>

Journal article

Li HK, Kaforou M, Rodriguez-Manzano J, Channon-Wells S, Monir A, Habgood-Coote D, Gupta RK, Mills EA, Lin J, Chiu Y-H, Pennisi I, Miglietta L, Mehta R, Obaray N, Herberg JA, Wright VJ, Georgiou P, Shallcross LJ, Mentzer AJ, Levin M, Cooke GS, Noursadeghi M, Sriskandan Set al., 2021, Discovery and validation of a 3-gene signature to distinguish COVID-19 and other viral infections in emergency infectious disease presentations; a case-control then observational cohort study, The Lancet Microbe, Vol: 2, Pages: 594-603, ISSN: 2666-5247

Background: Emergency admissions for infection often lack initial diagnostic certainty. COVID-19 has highlighted a need for novel diagnostic approaches to indicate likelihood of viral infection in a pandemic setting. We sought to derive and validate a blood transcriptional signature to detect viral infections including COVID-19 among adults with suspected infection presenting to the Emergency Department (ED).Methods: Blood RNA sequencing was performed on a discovery cohort of adults attending the ED with suspected infection who had subsequently-confirmed viral, bacterial, or no infection diagnoses. Differentially expressed host genes were subjected to feature selection to derive the most parsimonious discriminating signature. RT-qPCR validation of the signature was then performed in a prospective cohort of ED patients presenting with undifferentiated fever, and a second case-control cohort of ED patients with COVID-19 or bacterial infection. Signature performance was assessed by calculating area under receiver-operating characteristic curves (AUC-ROCs), sensitivities, and specificities.Findings: A 3-gene transcript signature was derived from the discovery cohort of 56 bacterial and 27 viral infection cases. In the validation cohort of 200 cases, the signature differentiated bacterial from viral infections with an AUC-ROC of 0.976 (95% CI: 0.919-1.000), sensitivity 97.3% and specificity of 100%. The AUC-ROC for C-reactive protein (CRP) and leucocyte count (WCC) was 0.833 (95% CI: 0.694-0.944) and 0.938 (95% CI: 0.840-0.986) respectively. The signature achieved higher net benefit in decision curve analysis than either CRP or WCC for discriminating viral infections from all other cases. In the second validation analysis the signature discriminated 35 bacterial infections from 34 SARS-CoV-2 positive COVID-19 infections with AUC-ROC of 0.953 (95% CI: 0.893-0.992), sensitivity 88.6% and specificity of 94.1%.Interpretation: This novel 3-gene signature discriminates viral i

Journal article

This data is extracted from the Web of Science and reproduced under a licence from Thomson Reuters. You may not copy or re-distribute this data in whole or in part without the written consent of the Science business of Thomson Reuters.

Request URL: http://wlsprd.imperial.ac.uk:80/respub/WEB-INF/jsp/search-html.jsp Request URI: /respub/WEB-INF/jsp/search-html.jsp Query String: respub-action=search.html&id=00167628&limit=30&person=true