RESUMO
Our Australian hospital tested almost 22 000 symptomatic people over 11 weeks for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in a multiplex polymerase chain reaction (PCR) assay. Following travel bans and physical distancing, SARS-CoV-2 and other respiratory viruses diagnoses fell dramatically. Increasing rhinovirus diagnoses as social control measures were relaxed may indirectly indicate an elevated risk of coronavirus disease 2019 (COVID-19) resurgence.
Assuntos
COVID-19 , SARS-CoV-2 , Austrália/epidemiologia , Hospitais , Humanos , Prevalência , Saúde PúblicaRESUMO
Pneumocystis jirovecii is an important opportunistic pathogen in immunocompromised patients. Molecular typing is employed to study this pathogen, as no culture system exists. No Australian P. jirovecii strains have been previously studied. Direct sequencing, targeting the internal transcribed spacer (ITS) regions of the nuclear rRNA operon, the mitochondrial large-subunit rRNA (mt LSU rRNA), and the dihydropteroate synthase (DHPS) gene, was performed on 68 Australian samples, collected between 2001 and 2007. Seven novel Australian ITS haplotypes (a composite of the ITS1 and ITS2 regions) were identified (SYD1m, SYD1g, Isyd2, Esyd3, Osyd4, Ag, and Hc). A dendrogram of published ITS haplotypes revealed that of the seven novel haplotypes, three (SYD1m, SYD1g, and Osyd4) are closely related to the haplotype Eg. Applying statistical parsimony, an Australian haplotype network was constructed which identified Eg as the ancestral haplotype, with two unresolved loops encountered. This suggests that the ITS lacks the resolution required for evolutionary analysis. Only two mt LSU rRNA genotypes were detected, with genotype 1 predominating. Mutant DHPS genotypes were present in 13% (8/60) of the samples. The novel haplotype Isyd2 was associated with less severe disease than the other Australian haplotypes. In contrast, patients with mutant DHPS genotypes were more likely to have severe disease, require invasive ventilation, and have a poor outcome than patients with wild-type DHPS genotypes. In conclusion, genetic clinical correlates continue to be found for Pneumocystis pneumonia; however, they remain controversial and warrant further study.
Assuntos
Infecções por Pneumocystis/epidemiologia , Infecções por Pneumocystis/microbiologia , Pneumocystis carinii/classificação , Pneumocystis carinii/isolamento & purificação , Adulto , Idoso , Austrália/epidemiologia , Análise por Conglomerados , DNA Fúngico/química , DNA Fúngico/genética , DNA Ribossômico/química , DNA Ribossômico/genética , DNA Espaçador Ribossômico/química , DNA Espaçador Ribossômico/genética , Di-Hidropteroato Sintase/genética , Evolução Molecular , Feminino , Proteínas Fúngicas/genética , Genótipo , Haplótipos , Humanos , Masculino , Pessoa de Meia-Idade , Epidemiologia Molecular , Dados de Sequência Molecular , Filogenia , Pneumocystis carinii/genética , Pneumocystis carinii/patogenicidade , Análise de Sequência de DNARESUMO
A total of 438 stool samples from 38 different species of animal from seven different locations were studied for the presence of Blastocystis. PCR analysis was completed on all samples and DNA sequence data from the rDNA were submitted to subtype allocation. There was a total of 80 (18%) sequences from 18 species, and nine different subtypes were identified - ST1, ST2, ST3, ST4, ST5, ST7, ST11, ST12 and ST13. This is the first report of Blastocystis from the eastern grey kangaroo, red kangaroo, wallaroo, snow leopard and ostrich. This study highlights the need for further investigation into the genetic diversity of Blastocystis which could help show the zoonotic potential of Blastocystis.
Assuntos
Aves , Infecções por Blastocystis/veterinária , Blastocystis/classificação , Blastocystis/isolamento & purificação , Mamíferos , Animais , Infecções por Blastocystis/epidemiologia , Infecções por Blastocystis/parasitologia , Fezes/parasitologia , New South Wales/epidemiologiaRESUMO
Early appropriate antibiotic treatment reduces mortality in severe sepsis, but current methods to identify antibiotic resistance still generally rely on bacterial culture. Modern diagnostics promise rapid gene detection, but the apparent diversity of relevant resistance genes in Enterobacteriaceae is a problem. Local surveys and analysis of publicly available data sets suggested that the resistance gene pool is dominated by a relatively small subset of genes, with a very high positive predictive value for phenotype. In this study, 152 Escherichia coli and 115 Klebsiella pneumoniae consecutive isolates with a cefotaxime, ceftriaxone and/or ceftazidime minimum inhibitory concentration (MIC) of ≥ 2 µg/mL were collected from seven major hospitals in Sydney (Australia) in 2008-2009. Nearly all of those with a MIC in excess of European Committee on Antimicrobial Susceptibility Testing (EUCAST) resistance breakpoints contained one or more representatives of only seven gene types capable of explaining this phenotype, and this included 96% of those with a MIC ≥ 2 µg/mL to any one of these drugs. Similarly, 97% of associated gentamicin-non-susceptibility (MIC ≥ 8 µg/mL) could be explained by three gene types. In a country like Australia, with a background prevalence of resistance to third-generation cephalosporins of 5-10%, this equates to a negative predictive value of >99.5% for non-susceptibility and is therefore suitable for diagnostic application. This is an important proof-of-principle that should be tested in other geographic locations.
Assuntos
Aminoglicosídeos/farmacologia , Antibacterianos/farmacologia , Cefalosporinas/farmacologia , Farmacorresistência Bacteriana , Escherichia coli/efeitos dos fármacos , Pool Gênico , Klebsiella pneumoniae/efeitos dos fármacos , Austrália , Escherichia coli/genética , Escherichia coli/isolamento & purificação , Infecções por Escherichia coli/microbiologia , Humanos , Infecções por Klebsiella/microbiologia , Klebsiella pneumoniae/genética , Klebsiella pneumoniae/isolamento & purificação , Testes de Sensibilidade MicrobianaRESUMO
Blood cultures (BC) are the most important tool in the diagnosis of bloodstream infections. However, false positive results are associated with increased laboratory costs and inappropriate antibiotic use. In order to determine the prevalence and location of blood cultures contaminated with coagulase-negative staphylococci (CNS), we performed a retrospective analysis of all blood cultures performed at St. Vincent's Hospital, Sydney during a 6-month period. From a total of 4234 patients with BC collected, CNS was isolated from 109 patients (2.6%). 94% of all CNS isolates (101/109) were contaminants. In the emergency department (ED), CNS isolates were significantly more likely to be contaminants (62/63, p<0.02) compared with the rest of the hospital, representing a 3.3% patient BC contamination rate. Treatment for a contaminant with vancomycin was significantly more likely to occur in ward patients (14/28, p<0.01) compared to the rest of the hospital. Duration of therapy did not differ across the hospital. Strategies to reduce the numbers of contaminants should be directed at medical staff in ED. Inappropriate vancomycin therapy could be curtailed by greater clinical microbiology liaison and vancomycin stewardship.
Assuntos
Bacteriemia/diagnóstico , Sangue/microbiologia , Coagulase/biossíntese , Infecções Estafilocócicas/diagnóstico , Staphylococcus/enzimologia , Staphylococcus/isolamento & purificação , Austrália , Bacteriemia/microbiologia , Reações Falso-Positivas , Hospitais , Humanos , Prevalência , Estudos Retrospectivos , Infecções Estafilocócicas/microbiologiaRESUMO
Entamoeba histolytica is one of the most common parasitic infections worldwide, infecting about 50 million people and resulting in 40,000-100,000 deaths a year. In Australia, people at risk of infection include immigrants, travellers returning from countries of high endemicity, Indigenous people, and men who have sex with men. Clinical manifestations range from asymptomatic carriage to invasive disease. Amoebic colitis and amoebic liver abscess are the most common invasive manifestations observed in Australia. Diagnosis depends on a high index of suspicion and laboratory investigations. Molecular methods (using the polymerase chain reaction) are the most sensitive for identifying and differentiating Entamoeba species. Treatment should always include a luminal agent to eradicate colonisation, prevent spread and/or reduce the risk of invasive disease. Medical therapy can successfully cure invasive disease, including amoebic liver abscesses.
Assuntos
Amebíase , Amebicidas/uso terapêutico , Entamoeba histolytica/crescimento & desenvolvimento , Metronidazol/uso terapêutico , Tinidazol/uso terapêutico , Amebíase/diagnóstico , Amebíase/tratamento farmacológico , Amebíase/fisiopatologia , Animais , Austrália/epidemiologia , Emigração e Imigração , Entamoeba histolytica/classificação , Entamoeba histolytica/patogenicidade , Humanos , Fatores de Risco , Comportamento Sexual , ViagemRESUMO
Class 2 integrons (Tn7) were found in all randomly selected epidemic (n = 27) and preepidemic (n = 13) strains of multiresistant Shigella sonnei biotype g. A class 1 integron was also found in two epidemic strains. Gene cassettes within these integrons account for resistance to commonly used therapeutic agents.