Search

We aimed to determine the incidence of Clostridium difficile infection (CDI), the molecular epidemiology of circulating C. difficile strains and risk factors for CDI among hospitalised children in the Auckland region. A cross-sectional study was undertaken of hospitalised children <15 years of age in two hospitals investigated for healthcare-associated diarrhoea between November 2011 and June 2012. Stool specimens were analysed for the presence of C. difficile using a two-step testing algorithm including polymerase chain reaction (PCR). C. difficile was cultured and PCR ribotyping performed. Demographic data, illness characteristics and risk factors were compared between children with and without CDI. Non-duplicate stool specimens were collected from 320 children with a median age of 1.2 years (range 3 days to 15 years). Forty-six patients (14 %) tested met the definition for CDI. The overall incidence of CDI was 2.0 per 10,000 bed days. The percentage of positive tests among neonates was only 2.6 %. PCR ribotyping showed a range of strains, with ribotype 014 being the most common. Significant risk factors for CDI were treatment with proton pump inhibitors [risk ratio (RR) 1.74, 95 % confidence interval (CI) 1.09-5.59; p = 0.002], presence of underlying malignancy (RR 2.71, 95 % CI 1.65-4.62; p = 0.001), receiving chemotherapy (RR 2.70, 95 % CI 1.41-4.83; p = 0.003) and exposure to antibiotics (RR 1.17, 95 % CI 0.99-1.17; p = 0.03). C. difficile is an important cause of healthcare-associated diarrhoea in this paediatric population. The notion that neonatal populations will always have high rates of colonisation with C. difficile may not be correct. Several risk factors associated with CDI among adults were also found to be significant. [ABSTRACT FROM AUTHOR]

Extended spectrum beta-lactamase producing E. coli (ESBL-EC) are an emerging public health issue. In New Zealand (NZ) , bla and bla are the most common ESBL genes. Although many studies describe risk factors for ESBL-EC, few describe risk factors for specific ESBL genes. Between January 2006 and December 2007, we characterized 108 consecutive, non-duplicate isolates of ESBL-EC at the Auckland Hospital laboratory. Demographic and clinical data were recorded. Of the 108, 54.6% (59) were CTX-M-15-EC, 26.9% (29) were CTX-M-14-EC and 12.09% were CTX-M-9 (13). The remaining seven isolates carried CTX-M-3 (3; 2.7%), CTX-M-65 (2; 1.8%), CTX-M-27 (1; 0.9%) and CTX-M-57 (1; 0.9%). CTX-M-15-EC were more likely than CTX-M-14-EC to be fluoroquinolone-resistant (86.4% versus 32.4%; p = 0.006) and to be non-susceptible to amoxicillin-clavulanate (84.7% versus 41.4%; p = 0.0001). Patients with CTX-M-15-EC were more likely to be of Indian ethnicity (34.5% versus 0%; p = 0.0012) and to have travelled recently (31.6% versus 4%; p = 0.0088). Patients with CTX-M-14-EC were more likely to have Chinese or South-East Asian ethnicity (48.1% versus 5.2%; p < 0.0001) and to have no history of either travel or prior hospital admission (44% versus 8.9%; p = 0.0006). These data imply that CTX-M-15 and CTX-M-14 producing E. coli are associated with distinct demographic subgroups in NZ. [ABSTRACT FROM AUTHOR]

The article reports on the influenza A (H1N1) virus which was first observed in the U.S. and Mexico in 2009. The virus was imported into New Zealand by a group of high school students returning from Mexico in April 2009. The students went through isolation quarantine which was conducted by government and health officials and other medical groups. The officials are closely monitoring the influenza A H1N1 virus to check if it would spread further to other countries.

Background: The aims of this study were to determine the clinical characteristics on arrival and the subsequent clinical outcome of HIV-infected UN quota refugees who settled in New Zealand during the last 11 years and to estimate their rate of HIV transmission. Methods: A population study was conducted. Data were provided by the Mangere Refugee Resettlement Centre, the infectious disease physicians caring for the subjects, the New Zealand AIDS Epidemiology Group and laboratories carrying out HIV viral load assays. Results: One hundred of 7732 (1.3%) UN quota refugees were HIV positive; mean age 30 years, 56% were men, median initial CD4 count was 320 (range 20–1358). HIV infection was most commonly acquired by heterosexual intercourse (74%). The median follow up was 5.0 years (range 1 month to 9.7 years). Five died and 15 subjects had 16 AIDS-defining illnesses, most commonly tuberculosis ( n = 10). Sixty subjects commenced highly active antiretroviral therapy of whom 36/59 (61%) had an undetectable HIV viral load after 1 year of treatment. None of the six children born to HIV-infected women in New Zealand were infected. There were two known cases of horizontal transmission of HIV infection. Conclusion: Although HIV-infected quota refugees often have to overcome severe social, cultural and financial handicaps, their clinical outcome is generally very good, with response rates to highly active antiretroviral therapy that are similar to other patient groups. Furthermore, they have not been a significant source of transmission of HIV infection after resettlement in New Zealand. [ABSTRACT FROM AUTHOR]

Background: There are no contemporary data on healthcare-associated infections (HAIs) in New Zealand., Aims: To determine the epidemiology of HAIs, prevalence of medical devices, and microbiology of HAIs in adults in public hospitals in New Zealand., Methods: Point prevalence survey. Surveyors reviewed patients aged ≥18 years using the HAI definitions of the European Centres for Disease Prevention and Control. Device use and microbiology of HAIs were recorded., Findings: In total, 5468 patients were surveyed; 361 patients (6.6%) had 423 HAIs (7.7 HAIs per 100 patients). The most common HAIs were: surgical site infections (N=104, 25%), urinary tract infections (N=80, 19%), pneumonia (N=75, 18%) and bloodstream infections (N=55, 13%). Overall, 3585 patients (66%) had at least one device, with 2922 (53%) patients having a peripheral intravenous catheter. Sixty-nine (16%) HAIs were device-associated. On multi-variable analysis, independent risk factors for HAIs included the presence of a peripheral [odds ratio (OR) 2.0] or central (OR 5.7) intravenous catheter and clinical service. HAI rates were higher in surgical patients (OR 1.8), intensive care unit patients (OR 2.6) and rehabilitation/older persons' health patients (OR 2.4) compared with general medicine patients (P≤0.01 for all groups). In total, 301 organisms were identified. Clostridioides difficile infection was uncommon, accounting for 1.7% of all HAIs. Forty-two isolates (14%) were drug-resistant, and most (N=33, 79%) were Enterobacterales., Conclusion: This study established the most common HAIs and their risk factors in New Zealand. The high prevalence of device use underscores the need to ensure that proven multi-modal prevention interventions are in place. However, as less than half of HAIs are device- or surgery-associated, other intervention strategies will be required to reduce their burden., (Copyright © 2022 The Author(s). Published by Elsevier Ltd.. All rights reserved.)

>We previously reported on a comparison of the AccuProbe(®) Gen-Probe(®) MTBC assay (AccuProbe) (BioMérieux, Marcy L'Etoile, France) with the Becton Dickinson (BD) MGIT™ TBc Identification (TBc) Test (BD, Franklin Lakes, NJ, USA) in our laboratory. In the period following the shift from the AccuProbe assay to the TBc test, we obtained six false-negative results. On sequencing the mpt64 gene, we found that these false-negative cases had mutations in the mpt64 gene due to deletion, insertion or substitution. Despite the occurrence of false-negative results, we found that the reduced cost and minimal technical expertise, combined with a new testing algorithm, still make this test the preferred option for rapidly identifying Mycobacterium tuberculosis complex in MGIT cultures in a low TB burden country such as New Zealand.

Our aim was to describe the epidemiology and incidence of community-onset invasive S. aureus disease in children presenting to our hospital, and to compare the clonal complexes and virulence genes of S. aureus strains causing invasive and non-invasive disease. The virulence gene repertoire of invasive disease isolates was characterized using DNA microarray and compared with the virulence gene repertoire of non-invasive S. aureus isolates. Over the study period, 163 children had an invasive S. aureus infection. There was no difference in the distribution of clonal complexes or in the prevalence of genes encoding virulence factors between invasive and non-invasive isolates. Future research should include a strong focus on identifying the host and environmental factors that, along with organism virulence factors, are contributing to the patterns of invasive S. aureus disease observed in New Zealand.

Objectives: Infective endocarditis due to non-toxigenic Corynebacterium diphtheriae is uncommon; we report 10 cases occurring over a 14-year period in Auckland, New Zealand and review the approach for treatment., Case Series: Eight of the 10 patients had known prosthetic valves or homografts in situ. Three patients required surgical intervention for infective endocarditis. Seven patients were treated with a combination of β-lactam and aminoglycoside, and one each was treated with a combination of vancomycin and an aminoglycoside, a β-lactam alone, and vancomycin alone. All patients survived and none relapsed., Review of Literature: The antibiotic treatment of 46 previously reported cases was reviewed; patients treated with a β-lactam and aminoglycoside (n=25), and without the addition of an aminoglycoside (n=11) were compared. The differences in length of treatment within each group make the comparison of outcome (mortality, need for surgical intervention, disease and treatment complications) difficult. However, regardless of the length of treatment, there was no difference in mortality or need for surgical intervention between the two groups in the currently published cases., Conclusions: Current evidence suggests that endocarditis of either native or prosthetic valves, caused by penicillin-susceptible C. diphtheriae, demonstrates a favorable outcome when treated with either a β-lactam alone or in combination with an aminoglycoside. Patient-specific factors will determine which approach is more appropriate for each individual patient., (Copyright © 2011 International Society for Infectious Diseases. Published by Elsevier Ltd. All rights reserved.)

The purpose of this study was to assess the epidemiology and outcomes of enterococcal bacteraemia. A retrospective review of demographic, microbiological and clinical data in patients 16 years of age and over with Enterococcus faecalis or E. faecium bacteraemia at Auckland City Hospital, New Zealand, from June 2002 to May 2007 was carried out. A total of 212 patients fulfilled the inclusion criteria, with 205 being included in the analysis. E. faecalis accounted for 86% (176/205) and E. faecium 14% (29/205) of the patients. Amoxycillin resistance occurred in 69% (20/29) of E. faecium isolates. High-level gentamicin resistance was present in 38% (65/171) of E. faecalis isolates and 25% (7/28) of E. faecium isolates (P = NS). No vancomycin-resistant enterococci were isolated. Healthcare association was present in 73% (149/205) of patients. Co-morbidities were present in 86% (176/205) of patients. The 7-day mortality was 13% (27/205) and the 30-day mortality 25% (52/205). On multivariate analysis, the 7-day mortality was statistically significantly associated with cirrhosis and shorter intravenous amoxycillin therapy. The 30-day mortality was statistically significantly associated with cirrhosis, malignancy, E. faecium bacteraemia and not receiving active antimicrobial therapy. No statistically significant association between high-level gentamicin resistance and mortality was demonstrated on multivariate analysis. Enterococcal bacteraemia occurs in a co-morbid, healthcare-exposed population. Associated mortality is high, and is associated with severe underlying disease, E. faecium bacteraemia and treatment factors.

We aimed to document the epidemiology of extended-spectrum beta-lactamase (ESBL)-producing enterobacteria in the Auckland community and identify factors associated with infection using a case-control study design. ESBL-producing enterobacteria were isolated from 107 infected patients, for which demographic and clinical data were available for 98 cases (92%). Escherichia coli was the predominant organism (82%), with urine as the commonest source (97%). Compared with a control group infected with ESBL-negative enterobacteria, factors significantly associated with infection on univariate analysis were: living in a residential care home (RCH); recent admission to hospital 'M'; recent antibiotic use; older age (>75 years); presence of a urinary catheter; and a history of comorbid chronic obstructive pulmonary disease (COPD), cardiovascular disease, neurological disease or recurrent urinary tract infection. On multivariate analysis, residence in RCH and COPD remained significant associations. Pulsed-field gel electrophoresis typing of the ESBL-producing E. coli identified a common strain. We concluded that residence in RCH and a history of COPD are significant associations with ESBL-producing enterobacterial infection in the Auckland community. Several spatial clusters in RCHs and a common strain suggest point-source outbreaks. A substantial number of community cases did not live in an RCH nor had been recently hospitalised, suggesting the independent generation of ESBL-producing enterobacteria in the broader community.

Aims: Despite availability of active antimicrobial agents for its treatment, the mortality from pneumococcal bacteraemia (PB) may reach 30% to 40% in high-risk groups. Greater vaccine use may reduce the incidence of PB. The aim of this study was to determine the proportion of patients with PB who had indications for, but had not received, pneumococcal vaccination., Methods: From December 1998 to March 2000, all episodes of PB in adults in four Auckland hospitals were followed prospectively. Underlying disease, outcome, and pneumococcal vaccination history were recorded., Results: 96 patients had PB: the median age was 63 years, range 16 to 93 years. 42 (44%) were > or = 65 years. The relative risk (RR) of acquiring PB for Maori and Pacific Island people was more than two times that of both European and other ethnic groups: RR 2.3 (95% CI 1.5 - 3.6) and 2.4 (1.6 - 3.8), respectively. The most common presentation was pneumonia; 84 (88%), of which 74 (88%) were community acquired. Five (5%) patients had meningitis. The overall mortality was 18%. Eleven (11%) pneumococcal isolates had intermediate susceptibility to penicillin and six (6%) were resistant. 69 (72%) patients had one or more condition for which pneumococcal vaccination is recommended but only two (2%) patients had received it. 82 (85%) patients were infected with serotypes included in the current pneumococcal vaccine., Conclusions: Most adult patients with PB have underlying medical conditions for which vaccination is recommended but only rare patients get vaccinated. Emerging antimicrobial resistance is a further incentive to increase the use of pneumococcal vaccination. Greater use of pneumococcal vaccine will probably require a change in its funding status, similar to the current policy for influenza vaccine. It may also be appropriate to consider targeted use of the vaccine in Maori and Pacific Island people given their higher rates of disease.

Background: Staphylococcus aureus bacteraemia (SAB) is a common complication of S. aureus infection and is associated with a high mortality., Aims: To document prospectively the pattern of illness associated with SAB in New Zealand and, by recording patient demographic factors and clinical features, to identify risk factors associated with a poor outcome., Methods: From 1 July 1996 to 31 December 1997, adults with SAB were prospectively studied in six tertiary care hospitals. All information obtained from patients' records was recorded on worksheets and transferred to a computerized spreadsheet for analysis., Results: There were 424 patients with SAB. Maori (relative risk (RR)= 1.8, 95% confidence interval (CI) = 1.3-2.6) and Pacific Island people (RR = 4.0, 95% CI = 3.1-5.3) were significantly more likely than people of European descent to acquire SAB, but not to die from the infection. Fifty per cent of cases were community acquired. A source was identified for 85%: intravenous catheter (31%), primarily hospital acquired, and skin/soft tissue (22%), primarily community acquired, were the most common foci. The 30-day mortality was 19%, 83% of whom died within 2 weeks. Risk factors for a poor outcome were: increasing age above 60, female sex (RR = 1.4, 95% CI = 1.0-2.1), diabetes mellitus (RR = 1.5, 95% CI = 1.0-2.4), immunosuppression (RR = 1.5, 95% CI = 1.0-2.4), pre-existing renal impairment (RR = 1.8, 95% CI = 1.2-2.7), malignancy (RR= 2.2, 95% CI = 1.4-3.5), lung as a source (RR = 2.8, 95% CI = 1.9-4.2) and unknown source (RR = 2.3, 95% CI = 1.5-3.3). Mortality was also accurately predicted by two multifactor scoring systems. There was a low rate of methicillin resistance (5%)., Conclusions: Staphylococcus aureus bacteraemia is more likely to occur in certain ethnic groups, while mortality is associated with other identifiable risk factors and continues to be high. Intravenous catheters remain the most common and most preventable cause of SAB.