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1.
Rev Med Virol ; 28(2)2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29377415

RESUMO

Respiratory syncytial virus (RSV) is a major cause of viral acute respiratory tract infections in young children. The virus is characterised by distinct seasonality that is dependent upon the latitude and its ability to cause reinfection. Respiratory syncytial virus demonstrates a complex molecular epidemiology pattern as multiple strains and/or genotypes cocirculate during a single epidemic. Previous studies have investigated the relationship between RSV genetic diversity, reinfection, and clinical features. Here, we review the evidence behind this relationship together with the impact that the advancement of whole genome sequencing will have upon our understanding and the need for reconsidering the classification of RSV genotypes.


Assuntos
Infecções por Vírus Respiratório Sincicial/epidemiologia , Infecções por Vírus Respiratório Sincicial/virologia , Vírus Sincicial Respiratório Humano/fisiologia , Variação Genética , Genoma Viral , Genômica/métodos , Genótipo , Geografia , Saúde Global , Humanos , Filogenia , Infecções por Vírus Respiratório Sincicial/diagnóstico , Vírus Sincicial Respiratório Humano/classificação
2.
BMC Infect Dis ; 18(1): 623, 2018 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-30518339

RESUMO

BACKGROUND: Salmonella is an important human pathogen in Australia and annual case rates continue to increase. In addition to foodborne exposures, cases have been associated with animal and contaminated environment contact. However, routine surveillance in Australia has tended to focus on humans and food, with no reported attempts to collate and compare Salmonella data from a wider range of potential sources of exposure. METHODS: Salmonella data from humans, food, animals and environments were collated from a range of surveillance and diagnostic sources in New South Wales (NSW). Data were categorised to reflect one of 29 sample origins. Serotype diversity was described for each category, and the distribution of serotypes commonly isolated from humans was examined for each sample origin. The distribution of serotypes along the livestock-food-human continuum and at the companion animal-wildlife interface was also examined. RESULTS: In total, 49,872 Salmonella isolates were included in this analysis, comprising 325 serotypes. The vast majority of these isolates were from humans (n = 38,106). Overall S. Typhimurium was the most frequently isolated serotype and was isolated from all sample categories except natural environment and game meat. S. Enteriditis was not isolated from any livestock animal, however sporadic cases were documented in food, companion animals and a reptile. Many serotypes that were frequently isolated from livestock animals and associated food products were only rarely isolated from humans. In addition, a number of key human serotypes were only sporadically isolated from livestock and food products, suggesting alternative sources of infection. In particular, S. Paratyphi B Java and S. Wangata were more often isolated from wild animals. Finally, there was some overlap between serotypes in companion animals and wildlife, with cats in particular having a large number of serotypes in common with wild birds. CONCLUSIONS: This is the most comprehensive description of Salmonella data from humans, food, livestock, wildlife, companion animals and various environments in Australia reported to date. Results confirm that livestock and food are important sources of salmonellosis in humans but that alternative sources - such as contact with wildlife and environments - warrant further investigation. Surveillance in NSW is largely human-focussed: major knowledge gaps exist regarding the diversity and frequency of serotypes in animals. More systematic surveillance of domestic animals and wildlife is needed to inform targeted control strategies and quantitative source attribution modelling in this state.


Assuntos
Animais Domésticos/microbiologia , Animais Selvagens/microbiologia , Microbiologia de Alimentos , Salmonelose Animal/microbiologia , Infecções por Salmonella/epidemiologia , Infecções por Salmonella/microbiologia , Salmonella/classificação , Animais , Austrália/epidemiologia , Aves/microbiologia , Gatos/microbiologia , Microbiologia Ambiental , Microbiologia de Alimentos/estatística & dados numéricos , Humanos , Gado/microbiologia , Carne/microbiologia , New South Wales/epidemiologia , Salmonella/genética , Salmonella/isolamento & purificação , Salmonelose Animal/epidemiologia , Sorogrupo , Sorotipagem
3.
Emerg Infect Dis ; 23(10)2017 10.
Artigo em Inglês | MEDLINE | ID: mdl-28930004

RESUMO

Hajj, the annual Muslim pilgrimage to Mecca, Saudi Arabia, is a unique mass gathering event that raises public health concerns in the host country and globally. Although gastroenteritis and diarrhea are common among Hajj pilgrims, the microbial etiologies of these infections are unknown. We collected 544 fecal samples from pilgrims with medically attended diarrheal illness from 40 countries during the 2011-2013 Hajj seasons and screened the samples for 16 pathogens commonly associated with diarrheal infections. Bacteria were the main agents detected, in 82.9% of the 228 positive samples, followed by viral (6.1%) and parasitic (5.3%) agents. Salmonella spp., Shigella/enteroinvasive Escherichia coli, and enterotoxigenic E. coli were the main pathogens associated with severe symptoms. We identified genes associated with resistance to third-generation cephalosporins ≈40% of Salmonella- and E. coli-positive samples. Hajj-associated foodborne infections pose a major public health risk through the emergence and transmission of antimicrobial drug-resistant bacteria.


Assuntos
Disenteria Bacilar/epidemiologia , Escherichia coli Enterotoxigênica/isolamento & purificação , Infecções por Escherichia coli/epidemiologia , Islamismo , Infecções por Salmonella/epidemiologia , Salmonella/isolamento & purificação , Shigella/isolamento & purificação , Adulto , Disenteria Bacilar/diagnóstico , Disenteria Bacilar/microbiologia , Disenteria Bacilar/transmissão , Escherichia coli Enterotoxigênica/genética , Escherichia coli Enterotoxigênica/patogenicidade , Infecções por Escherichia coli/diagnóstico , Infecções por Escherichia coli/microbiologia , Infecções por Escherichia coli/transmissão , Fezes/microbiologia , Feminino , Férias e Feriados , Humanos , Masculino , Comportamento de Massa , Pessoa de Meia-Idade , Saúde Pública/estatística & dados numéricos , Salmonella/genética , Salmonella/patogenicidade , Infecções por Salmonella/diagnóstico , Infecções por Salmonella/microbiologia , Infecções por Salmonella/transmissão , Arábia Saudita/epidemiologia , Shigella/genética , Shigella/patogenicidade , Viagem
4.
BMC Med ; 14: 31, 2016 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-27005572

RESUMO

BACKGROUND: Combating the spread of drug resistant tuberculosis is a global health priority. Whole genome association studies are being applied to identify genetic determinants of resistance to anti-tuberculosis drugs. Protein structure and interaction modelling are used to understand the functional effects of putative mutations and provide insight into the molecular mechanisms leading to resistance. METHODS: To investigate the potential utility of these approaches, we analysed the genomes of 144 Mycobacterium tuberculosis clinical isolates from The Special Programme for Research and Training in Tropical Diseases (TDR) collection sourced from 20 countries in four continents. A genome-wide approach was applied to 127 isolates to identify polymorphisms associated with minimum inhibitory concentrations for first-line anti-tuberculosis drugs. In addition, the effect of identified candidate mutations on protein stability and interactions was assessed quantitatively with well-established computational methods. RESULTS: The analysis revealed that mutations in the genes rpoB (rifampicin), katG (isoniazid), inhA-promoter (isoniazid), rpsL (streptomycin) and embB (ethambutol) were responsible for the majority of resistance observed. A subset of the mutations identified in rpoB and katG were predicted to affect protein stability. Further, a strong direct correlation was observed between the minimum inhibitory concentration values and the distance of the mutated residues in the three-dimensional structures of rpoB and katG to their respective drugs binding sites. CONCLUSIONS: Using the TDR resource, we demonstrate the usefulness of whole genome association and convergent evolution approaches to detect known and potentially novel mutations associated with drug resistance. Further, protein structural modelling could provide a means of predicting the impact of polymorphisms on drug efficacy in the absence of phenotypic data. These approaches could ultimately lead to novel resistance mutations to improve the design of tuberculosis control measures, such as diagnostics, and inform patient management.


Assuntos
Proteínas de Bactérias/química , Farmacorresistência Bacteriana Múltipla/genética , Genoma Bacteriano , Modelos Moleculares , Mycobacterium tuberculosis/genética , Tuberculose Resistente a Múltiplos Medicamentos/microbiologia , Antituberculosos/uso terapêutico , Proteínas de Bactérias/genética , Estudo de Associação Genômica Ampla , Humanos , Isoniazida/uso terapêutico , Testes de Sensibilidade Microbiana , Mutação , Mycobacterium tuberculosis/isolamento & purificação , Mycobacterium tuberculosis/metabolismo , Conformação Proteica , Análise de Sequência de DNA , Tuberculose Resistente a Múltiplos Medicamentos/tratamento farmacológico , Tuberculose Resistente a Múltiplos Medicamentos/genética , Tuberculose Resistente a Múltiplos Medicamentos/metabolismo
5.
J Clin Microbiol ; 54(8): 2014-22, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-27225410

RESUMO

Human infections with Salmonella enterica subspecies enterica serovar Senftenberg are often associated with exposure to poultry flocks, farm environments, or contaminated food. The recent emergence of multidrug-resistant isolates has raised public health concerns. In this study, comparative genomics and phenotypic analysis were used to characterize 14 Salmonella Senftenberg clinical isolates recovered from multiple outbreaks in Shenzhen and Shanghai, China, between 2002 and 2011. Single-nucleotide polymorphism analyses identified two phylogenetically distinct clades of S Senftenberg, designated SC1 and SC2, harboring variations in Salmonella pathogenicity island 1 (SPI-1) and SPI-2 and exhibiting distinct biochemical and phenotypic signatures. Although the two variants shared the same serotype, the SC2 isolates of sequence type 14 (ST14) harbored intact SPI-1 and -2 and hence were characterized by possessing efficient invasion capabilities. In contrast, the SC1 isolates had structural deletion patterns in both SPI-1 and -2 that correlated with an impaired capacity to invade cultured human cells and also the year of their isolation. These atypical SC1 isolates also lacked the capacity to produce hydrogen sulfide. These findings highlight the emergence of atypical Salmonella Senftenberg variants in China and provide genetic validation that variants lacking SPI-1 and regions of SPI-2, which leads to impaired invasion capacity, can still cause clinical disease. These data have identified an emerging public health concern and highlight the need to strengthen surveillance to detect the prevalence and transmission of nontyphoidal Salmonella species.


Assuntos
Surtos de Doenças , Infecções por Salmonella/epidemiologia , Infecções por Salmonella/microbiologia , Salmonella enterica/classificação , Salmonella enterica/isolamento & purificação , Sorogrupo , Adulto , Idoso , Técnicas de Tipagem Bacteriana , China/epidemiologia , Análise por Conglomerados , Feminino , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Fenótipo , Filogenia , Polimorfismo de Nucleotídeo Único , Salmonella enterica/genética , Adulto Jovem
6.
J Clin Microbiol ; 53(9): 2846-53, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26109442

RESUMO

Infant botulism is a potentially life-threatening paralytic disease that can be associated with prolonged morbidity if not rapidly diagnosed and treated. Four infants were diagnosed and treated for infant botulism in NSW, Australia, between May 2011 and August 2013. Despite the temporal relationship between the cases, there was no close geographical clustering or other epidemiological links. Clostridium botulinum isolates, three of which produced botulism neurotoxin serotype A (BoNT/A) and one BoNT serotype B (BoNT/B), were characterized using whole-genome sequencing (WGS). In silico multilocus sequence typing (MLST) found that two of the BoNT/A-producing isolates shared an identical novel sequence type, ST84. The other two isolates were single-locus variants of this sequence type (ST85 and ST86). All BoNT/A-producing isolates contained the same chromosomally integrated BoNT/A2 neurotoxin gene cluster. The BoNT/B-producing isolate carried a single plasmid-borne bont/B gene cluster, encoding BoNT subtype B6. Single nucleotide polymorphism (SNP)-based typing results corresponded well with MLST; however, the extra resolution provided by the whole-genome SNP comparisons showed that the isolates differed from each other by >3,500 SNPs. WGS analyses indicated that the four infant botulism cases were caused by genomically distinct strains of C. botulinum that were unlikely to have originated from a common environmental source. The isolates did, however, cluster together, compared with international isolates, suggesting that C. botulinum from environmental reservoirs throughout NSW have descended from a common ancestor. Analyses showed that the high resolution of WGS provided important phylogenetic information that would not be captured by standard seven-loci MLST.


Assuntos
Botulismo/epidemiologia , Clostridium botulinum/classificação , Clostridium botulinum/isolamento & purificação , Genótipo , Tipagem de Sequências Multilocus , Toxinas Botulínicas Tipo A/genética , Botulismo/microbiologia , Clostridium botulinum/genética , Genoma Bacteriano , Humanos , Lactente , Epidemiologia Molecular , New South Wales/epidemiologia , Filogenia , Polimorfismo de Nucleotídeo Único
7.
J Antimicrob Chemother ; 70(4): 1198-202, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25492392

RESUMO

OBJECTIVES: Phenotypic drug susceptibility testing (DST) for Mycobacterium tuberculosis takes several weeks to complete and second-line DST is often poorly reproducible, potentially leading to compromised clinical decisions. Following a fatal case of XDR TB, we investigated the potential benefit of using whole-genome sequencing to generate an in silico drug susceptibility profile. METHODS: The clinical course of the patient was reviewed, assessing the times at which phenotypic DST data became available and changes made to the therapeutic regimen. Whole-genome sequencing was performed on the earliest available isolate and variants associated with drug resistance were identified. RESULTS: The final DST report, including second-line drugs, was issued 10 weeks after patient presentation and 8 weeks after initial growth of M. tuberculosis. In the interim, the patient may have received a compromised regimen that had the potential to select for further drug resistance. The in silico susceptibility profile, extrapolated from evolving evidence in the literature, provided comparable or superior data to the DST results for second-line drugs and could be generated in a much shorter timeframe. CONCLUSIONS: We propose routine whole-genome sequencing of all MDR M. tuberculosis isolates in adequately resourced settings. This will improve individual patient care, monitor for transmission events and advance our understanding of resistance-associated mutations.


Assuntos
Farmacorresistência Bacteriana Múltipla , Tuberculose Extensivamente Resistente a Medicamentos/diagnóstico , Genoma Bacteriano , Técnicas de Genotipagem/métodos , Testes de Sensibilidade Microbiana/métodos , Mycobacterium tuberculosis/isolamento & purificação , Análise de Sequência de DNA , Adulto , Tuberculose Extensivamente Resistente a Medicamentos/tratamento farmacológico , Tuberculose Extensivamente Resistente a Medicamentos/microbiologia , Humanos , Masculino , Mycobacterium tuberculosis/efeitos dos fármacos , Mycobacterium tuberculosis/genética
8.
BMC Genomics ; 15: 991, 2014 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-25407810

RESUMO

BACKGROUND: Multidrug- (MDR) and extensively drug resistant (XDR) tuberculosis (TB) presents a challenge to disease control and elimination goals. In Lisbon, Portugal, specific and successful XDR-TB strains have been found in circulation for almost two decades. RESULTS: In the present study we have genotyped and sequenced the genomes of 56 Mycobacterium tuberculosis isolates recovered mostly from Lisbon. The genotyping data revealed three major clusters associated with MDR-TB, two of which are associated with XDR-TB. Whilst the genomic data contributed to elucidate the phylogenetic positioning of circulating MDR-TB strains, showing a high predominance of a single SNP cluster group 5. Furthermore, a genome-wide phylogeny analysis from these strains, together with 19 publicly available genomes of Mycobacterium tuberculosis clinical isolates, revealed two major clades responsible for M/XDR-TB in the region: Lisboa3 and Q1 (LAM).The data presented by this study yielded insights on microevolution and identification of novel compensatory mutations associated with rifampicin resistance in rpoB and rpoC. The screening for other structural variations revealed putative clade-defining variants. One deletion in PPE41, found among Lisboa3 isolates, is proposed to contribute to immune evasion and as a selective advantage. Insertion sequence (IS) mapping has also demonstrated the role of IS6110 as a major driver in mycobacterial evolution by affecting gene integrity and regulation. CONCLUSIONS: Globally, this study contributes with novel genome-wide phylogenetic data and has led to the identification of new genomic variants that support the notion of a growing genomic diversity facing both setting and host adaptation.


Assuntos
Farmacorresistência Bacteriana Múltipla/genética , Evolução Molecular , Variação Genética , Genoma Bacteriano , Mycobacterium tuberculosis/efeitos dos fármacos , Mycobacterium tuberculosis/genética , Antituberculosos/farmacologia , Proteínas de Bactérias/genética , Mapeamento Cromossômico , Biologia Computacional , Loci Gênicos , Instabilidade Genômica , Genômica , Genótipo , Humanos , Mutação INDEL , Testes de Sensibilidade Microbiana , Repetições Minissatélites , Filogenia , Polimorfismo de Nucleotídeo Único , Portugal/epidemiologia , Tuberculose Resistente a Múltiplos Medicamentos/epidemiologia , Tuberculose Resistente a Múltiplos Medicamentos/microbiologia
9.
PLoS Pathog ; 8(3): e1002567, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22457617

RESUMO

Toxoplasma gondii is a zoonotic protozoan parasite which infects nearly one third of the human population and is found in an extraordinary range of vertebrate hosts. Its epidemiology depends heavily on horizontal transmission, especially between rodents and its definitive host, the cat. Neospora caninum is a recently discovered close relative of Toxoplasma, whose definitive host is the dog. Both species are tissue-dwelling Coccidia and members of the phylum Apicomplexa; they share many common features, but Neospora neither infects humans nor shares the same wide host range as Toxoplasma, rather it shows a striking preference for highly efficient vertical transmission in cattle. These species therefore provide a remarkable opportunity to investigate mechanisms of host restriction, transmission strategies, virulence and zoonotic potential. We sequenced the genome of N. caninum and transcriptomes of the invasive stage of both species, undertaking an extensive comparative genomics and transcriptomics analysis. We estimate that these organisms diverged from their common ancestor around 28 million years ago and find that both genomes and gene expression are remarkably conserved. However, in N. caninum we identified an unexpected expansion of surface antigen gene families and the divergence of secreted virulence factors, including rhoptry kinases. Specifically we show that the rhoptry kinase ROP18 is pseudogenised in N. caninum and that, as a possible consequence, Neospora is unable to phosphorylate host immunity-related GTPases, as Toxoplasma does. This defense strategy is thought to be key to virulence in Toxoplasma. We conclude that the ecological niches occupied by these species are influenced by a relatively small number of gene products which operate at the host-parasite interface and that the dominance of vertical transmission in N. caninum may be associated with the evolution of reduced virulence in this species.


Assuntos
Coccidiose/parasitologia , Genômica , Neospora/genética , Toxoplasma/genética , Toxoplasmose/parasitologia , Animais , Coccidiose/transmissão , Hibridização Genômica Comparativa , Regulação da Expressão Gênica , Interações Hospedeiro-Parasita/fisiologia , Transmissão Vertical de Doenças Infecciosas , Neospora/patogenicidade , Toxoplasma/patogenicidade , Toxoplasmose/transmissão , Virulência , Zoonoses/transmissão
10.
Lung India ; 41(3): 185-191, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38687229

RESUMO

BACKGROUND: Arbaeen in Iraq has been one of the largest mass gatherings during the COVID-19 pandemic with 14.5 million attendees in 2020. We set out to assess the prevalence of current or past COVID-19 among 2020 Arbaeen participants, and establish associations between COVID-19 test results, symptoms, and known recent exposure. METHODS: This was a cross-sectional study involving participants who joined Arbaeen walk in Iraq in October 2020. COVID-19 PCR and/or rapid antibody test were conducted among consented participants. A short questionnaire was administered. Rapid antibody testing was done onsite. Nasal and throat swab samples were transferred to the laboratory for PCR testing. RESULTS: A total of 835 (88.3% male; 11.7% female) participants were recruited. The most common symptom overall was cough (9.6%) followed by sore throat, fever, and loss of taste/smell (6.6%, 5.5%, and 5.0%, respectively). One in five (20.3%) participants reported close contact with a confirmed COVID-19 case in the past 14 days. Of the 237 participants with a PCR test, 18 (7.6%) were positive. Of the 765 participants with rapid antibody test, 19.3% tested positive for IgM, 39.3% for IgG, and 16.4% for both. Approximately 40% of the participants had evidence of current or past COVID-19 infection based on antibody and PCR. CONCLUSIONS: The almost 1 in 10 COVID-19 cases within such a multimillion person gathering, illustrates the difficulty in limiting the participation of infectious individuals in religious mass gatherings. There is a pressing need to explore measures to reduce the risk of transmission of infectious diseases at major mass gathering events.

12.
Microb Genom ; 9(9)2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37656160

RESUMO

Respiratory syncytial virus (RSV), or human orthopneumovirus, is a major cause of acute lower respiratory infection (ALRI), particularly in young children, causing significant morbidity and mortality. We used pathogen genomics to characterize the population structure and genetic signatures of RSV isolates circulating in children in New South Wales between 2016 and 2018 and to understand the evolutionary dynamics of these strains in the context of publicly available RSV genomes from the region and globally. Whole-genome phylogenetic analysis demonstrated the co-circulation of a few major RSV clades in the paediatric population from Sydney. The whole-genome-based genotypes A23 (RSV-A ON1-like genotype) and B6 (RSV-B BA9-like genotype) were the predominant RSV-A and RSV-B genotypes circulating during the study period, respectively. These genotypes were characterized with high levels of diversity of predicted N- and O-linked glycosylation patterns in both the G and F glycoproteins. Interestingly, a novel 72-nucleotide triplication in the sequence that corresponds to the C-terminal region of the G gene was identified in four of the A23 genotype sequenced in this study. Consistently, the population dynamics analysis demonstrated a continuous increase in the effective population size of A23 and B6 genotypes globally. Further investigations including functional mapping of mutations and identifying the impact of sequence changes on virus fitness are highly required. This study highlights the potential impact of an integrated approach that uses WG-based phylogeny and studying selective pressure events in understanding the emergence and dissemination of RSV genotypes.


Assuntos
Genômica , Infecções Respiratórias , Criança , Humanos , Pré-Escolar , Filogenia , Vírus Sinciciais Respiratórios , Genótipo , Austrália
13.
J Neurol Neurosurg Psychiatry ; 83(3): 298-304, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22056965

RESUMO

BACKGROUND: Alemtuzumab is a lymphocyte depleting monoclonal antibody that has demonstrated superior efficacy over interferon ß-1a for relapsing-remitting multiple sclerosis (MS), and is currently under investigation in phase 3 trials. One unresolved issue is the duration and significance of the lymphopenia induced. The long term effects on lymphocyte reconstitution of a single course, and the consequences that this has on disability, morbidity, mortality and autoimmunity, were examined. METHODS: The lymphocyte reconstitution (n=36; 384 person years) and crude safety data (n=37; 447 person years) are reported for the first patients with progressive MS to receive alemtuzumab (1991-1997). Reconstitution time was expressed as a geometric mean or, when a non-negligible number of individuals failed to recover, as a median using survival analysis. RESULTS: Geometric mean recovery time (GMRT) of total lymphocyte counts to the lower limit of the normal range (LLN; ≥1.0×10(9) cells/l) was 12.7 months (95% CI 8.8 to 18.2 months). For B cells, GMRT to LLN (≥0.1×10(9)/l) was 7.1 months (95% CI 5.3 to 9.5); median recovery times for CD8 (LLN ≥0.2×10(9) cells/l) and CD4 lymphocytes (LLN ≥0.4×10(9) cells/l) were 20 months and 35 months, respectively. However, CD8 and CD4 counts recovered to baseline levels in only 30% and 21% of patients, respectively. No infective safety concerns arose during 447 person years of follow-up. CONCLUSIONS: Lymphocyte counts recovered to LLN after a single course of alemtuzumab in approximately 8 months (B cells) and 3 years (T cell subsets), but usually did not recover to baseline values. However, this long lasting lymphopenia in patients with a previously normal immune system was not associated with an increased risk of serious opportunistic infection.


Assuntos
Anticorpos Monoclonais Humanizados/uso terapêutico , Anticorpos Antineoplásicos/uso terapêutico , Linfopenia/induzido quimicamente , Esclerose Múltipla Crônica Progressiva/tratamento farmacológico , Adulto , Alemtuzumab , Anticorpos Monoclonais Humanizados/efeitos adversos , Anticorpos Antineoplásicos/efeitos adversos , Linfócitos T CD4-Positivos/efeitos dos fármacos , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/efeitos dos fármacos , Linfócitos T CD8-Positivos/imunologia , Feminino , Humanos , Contagem de Linfócitos , Subpopulações de Linfócitos/efeitos dos fármacos , Subpopulações de Linfócitos/imunologia , Linfócitos/efeitos dos fármacos , Linfócitos/imunologia , Masculino , Pessoa de Meia-Idade , Esclerose Múltipla Crônica Progressiva/imunologia , Fatores de Tempo , Adulto Jovem
14.
J Immunol ; 185(1): 763-8, 2010 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-20519651

RESUMO

Biological therapies, even humanized mAbs, may induce antiglobulin responses that impair efficacy. We tested a novel strategy to induce tolerance to a therapeutic mAb. Twenty patients with relapsing-remitting multiple sclerosis received an initial cycle of alemtuzumab (Campath-1H), up to 120 mg over 5 d, preceded by 500 mg SM3. This Ab differs from alemtuzumab by a single point mutation and is designed not to bind to cells. Twelve months later, they received a second cycle of alemtuzumab, up to 72 mg over 3 d. One month after that, 4 of 19 (21%) patients had detectable serum anti-alemtuzumab Abs compared with 145 of 197 (74%) patients who received two cycles of alemtuzumab without SM3 in the phase 2 CAMMS223 trial (p < 0.001). The efficacy and safety profile of alemtuzumab was unaffected by SM3 pretreatment. Long-lasting "high-zone" tolerance to a biological therapy may be induced by pretreatment with a high i.v. dose of a drug variant, altered to reduce target-binding.


Assuntos
Anticorpos Monoclonais/uso terapêutico , Anticorpos Antineoplásicos/uso terapêutico , Tolerância Imunológica , Esclerose Múltipla Recidivante-Remitente/imunologia , Esclerose Múltipla Recidivante-Remitente/terapia , Adolescente , Adulto , Alemtuzumab , Substituição de Aminoácidos/genética , Substituição de Aminoácidos/imunologia , Anticorpos Anti-Idiotípicos/biossíntese , Anticorpos Anti-Idiotípicos/sangue , Anticorpos Monoclonais/genética , Anticorpos Monoclonais/imunologia , Anticorpos Monoclonais Humanizados , Anticorpos Antineoplásicos/genética , Anticorpos Antineoplásicos/imunologia , Relação Dose-Resposta Imunológica , Esquema de Medicação , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Esclerose Múltipla Recidivante-Remitente/diagnóstico , Projetos Piloto , Mutação Puntual/genética , Mutação Puntual/imunologia , Ensaios Clínicos Controlados Aleatórios como Assunto , Resultado do Tratamento , Adulto Jovem
15.
Access Microbiol ; 4(4): 000338, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35812707

RESUMO

Hajj is associated with an increased risk of the transmission of infectious diseases including upper respiratory tract infections (URTIs). It can be a focal point for the emergence, persistence and dissemination of antimicrobial-resistant (AMR) bacteria. The overuse of antibiotics during Hajj can promote the development of antimicrobial resistance. Little information is known regarding the true appropriateness of prescribing antibiotics for treating URTIs during Hajj. Here we studied the rate, patterns and appropriateness of antibiotic prescription among a cohort of pilgrims who were treated for URTIs during the 2018 Hajj season. Adult pilgrims who sought medical services for URTIs [presenting with coryza, runny nose, nasal irritation, nasal congestion, cough, sore throat, headache or fever (even if subjective)] within the Holy sites were enrolled in this study and consented to provide swabs and medical information. A total of 121 pilgrims were enrolled, with the majority (60.3 %) originating from North African Arab countries. Most were male (89.3 %) with a median age of 45 years. Bacterial infections were detected in 7.3 % (n=9) of the URTI cases. The identified bacteria included Haemophilus influenzae (n=6, all resistant to ampicillin), Streptococcus pneumoniae (n=2), Staphylococcus aureus (n=1, resistant to oxacillin) and Moraxella catarrhalis (n=1, resistant to ampicillin and trimethoprim/sulfamethoxazole). The antibiotic prescription rate was 52.1%, most of which was amoxicillin (81 %). The data demonstrated that the proportion of appropriate practices in treating bacterial URTIs in this cohort was 45.5 %. This study highlights the need for implementing laboratory identification of the aetiological agents and related AMR profiles when treating URTIs in Hajj, rather than relying on clinical assessment alone.

16.
Trop Med Infect Dis ; 6(1)2021 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-33467065

RESUMO

There is increasing evidence that human movement facilitates the global spread of resistant bacteria and antimicrobial resistance (AMR) genes. We systematically reviewed the literature on the impact of travel on the dissemination of AMR. We searched the databases Medline, EMBASE and SCOPUS from database inception until the end of June 2019. Of the 3052 titles identified, 2253 articles passed the initial screening, of which 238 met the inclusion criteria. The studies covered 30,060 drug-resistant isolates from 26 identified bacterial species. Most were enteric, accounting for 65% of the identified species and 92% of all documented isolates. High-income countries were more likely to be recipient nations for AMR originating from middle- and low-income countries. The most common origin of travellers with resistant bacteria was Asia, covering 36% of the total isolates. Beta-lactams and quinolones were the most documented drug-resistant organisms, accounting for 35% and 31% of the overall drug resistance, respectively. Medical tourism was twice as likely to be associated with multidrug-resistant organisms than general travel. International travel is a vehicle for the transmission of antimicrobial resistance globally. Health systems should identify recent travellers to ensure that adequate precautions are taken.

17.
Artigo em Inglês | MEDLINE | ID: mdl-33810092

RESUMO

COVID-19 poses grave challenges for mass gatherings. One of the world's largest annual gatherings, Arbaeen, occurs in Iraq. We studied respiratory symptoms and risk and protective factors using representative sampling of Arbaeen pilgrims in 2019 to inform prevention of COVID-19 transmission. Structured sampling was used to recruit walking pilgrims. A questionnaire asked about respiratory symptoms, risk, and preventive factors, including hygiene-related resources of toilet facilities. The commonest symptom reported by the 1842 participants (63.3% male, 36.7% female) was cough (25.6%). Eating in mawkibs (rest areas) with indoor kitchens and drinking only packaged water were associated with lower risk of cough (AOR = 0.72, CI = 0.56-0.94; AOR = 0.60; CI = 0.45-0.78, p < 0.05). Facemask use was associated with increased risk of cough (AOR = 2.71, CI = 2.08-3.53, p < 0.05). Handwashing was not protective against cough, or against (one or more of) cough, fever, or breathlessness in multivariate analysis. Toilet facilities often lacked running water (32.1%) and soap (26.1%), and had shared hand towels (17%). To reduce risk of respiratory infections including COVID-19 during Arbaeen or other mass gatherings, needs include running water, soap, and hygienic hand drying options or hand sanitiser. Education on proper handwashing and facemask approaches and monitoring around food preparation and eating spaces are needed.


Assuntos
COVID-19 , Pandemias , Feminino , Desinfecção das Mãos , Humanos , Iraque , Masculino , Máscaras , SARS-CoV-2
18.
Microb Genom ; 7(6)2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-34110281

RESUMO

Enterotoxigenic Escherichia coli (ETEC) expressing the colonization pili CFA/I are common causes of diarrhoeal infections in humans. Here, we use a combination of transposon mutagenesis and transcriptomic analysis to identify genes and pathways that contribute to ETEC persistence in water environments and colonization of a mammalian host. ETEC persisting in water exhibit a distinct RNA expression profile from those growing in richer media. Multiple pathways were identified that contribute to water survival, including lipopolysaccharide biosynthesis and stress response regulons. The analysis also indicated that ETEC growing in vivo in mice encounter a bottleneck driving down the diversity of colonizing ETEC populations.


Assuntos
Escherichia coli Enterotoxigênica/crescimento & desenvolvimento , Escherichia coli Enterotoxigênica/genética , Proteínas de Escherichia coli/genética , Proteínas de Fímbrias/genética , Microbiologia da Água , Animais , Modelos Animais de Doenças , Escherichia coli Enterotoxigênica/isolamento & purificação , Infecções por Escherichia coli , Feminino , Proteínas de Fímbrias/isolamento & purificação , Fímbrias Bacterianas , Genes Bacterianos/genética , Camundongos , Camundongos Endogâmicos C57BL , Fenótipo , Água
19.
Infect Disord Drug Targets ; 20(3): 259-266, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-30277167

RESUMO

In this review, Ebolavirus Disease (EVD) outbreaks have been comprehensively reviewed from their beginning until now. It chronologically discusses how each outbreak was tackled, national and international actions taken, diagnostic methods applied, the infection control procedures put in place, and the lessons learnt from each epidemic for the control of subsequent epidemics. Data for this review were obtained from literature published between 1967 and 2016 in key medical databases, the official websites of various governmental organisations, international public health agencies, and regulatory bodies. Despite major developments in the field of EVD, there has been little progress in its specific therapy or prevention. Historically, individuals who recovered from EVD acted as a source of fresh frozen plasma (containing IgG) that has been used to treat other acutely ill patients, however this therapeutic modality has limitations due to the risk of transmission of blood-borne infections. With the use of advanced and efficient purification methods the incidence of unwanted side effects following immune serum therapy has currently been greatly reduced. Creation of a safe plasma pool that covers immunoglobulins against all strains of EVD is now a research priority. Recommendations on how future EVD outbreaks can be better managed have been discussed.


Assuntos
Surtos de Doenças/história , Surtos de Doenças/prevenção & controle , Doença pelo Vírus Ebola/história , Doença pelo Vírus Ebola/prevenção & controle , África/epidemiologia , Ensaios Clínicos como Assunto , Ebolavirus/patogenicidade , Doença pelo Vírus Ebola/epidemiologia , História do Século XX , História do Século XXI , Humanos , Incidência , Estudos Observacionais como Assunto
20.
Trop Med Infect Dis ; 5(1)2020 01 29.
Artigo em Inglês | MEDLINE | ID: mdl-32013238

RESUMO

Antimicrobial resistance (AMR) is a global public health issue. Upper respiratory tract infections (URTIs) are common illnesses during Hajj, for which antibiotics are often inappropriately prescribed. Hajj healthcare workers' (HCW) knowledge, attitudes and perceptions (KAP) about AMR and antibiotic use for URTIs are not known. We conducted a survey among HCWs during Hajj to explore their KAP regarding antibiotic use for URTIs in pilgrims. Electronic or paper-based surveys were distributed to HCWs during the Hajj in 2016 and 2017. A total of 85 respondents aged 25 to 63 (median 40) years completed the surveys. Most participants were male (78.8%) and were physicians by profession (95.3%). Around 85% and 19% of respondents claimed to have heard about AMR and antimicrobial stewardship programs, respectively, among whom most had obtained their knowledge during their qualification. Implementation of URTI treatment guidelines was very low. In conclusion, HCWs at Hajj have significant knowledge gaps regarding AMR, often do not use standard clinical criteria to diagnose URTIs and display a tendency to prescribe antibiotics for URTIs.

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