Communicable Diseases Intelligence最新文献

Global forced displacement has climbed to unprecedented levels due largely to regional conflict. Degraded public health services leave displaced people vulnerable to multiple environmental and infectious hazards including vaccine preventable disease. While diphtheria is rarely notified in New Zealand, a 2 person outbreak of cutaneous diphtheria occurred in refugees from Afghanistan in February 2015 at the refugee resettlement centre in Auckland. Both cases had uncertain immunisation status. The index case presented with a scalp lesion during routine health screen and toxigenic Corynebacterium diphtheriae was isolated. A secondary case of cutaneous diphtheria and an asymptomatic carrier were identified from skin and throat swabs. The 2 cases and 1 carrier were placed in consented restriction until antibiotic treatment and 2 clearance swabs were available. A total of 164 contacts were identified from within the same hostel accommodation as well as staff working in the refugee centre. All high risk contacts (n=101) were swabbed (throat, nasopharynx and open skin lesions) to assess C. diphtheriae carriage status. Chemoprophylaxis was administered (1 dose of intramuscular benzathine penicillin or 10 days of oral erythromycin) and diphtheria toxoid-containing vaccine offered regardless of immunisation status. Suspected cases were restricted on daily monitoring until swab clearance. A group of 49 low risk contacts were also offered vaccination. Results suggest a significant public health effort was required for a disease rarely seen in New Zealand. In light of increased worldwide forced displacement, similar outbreaks could occur and require a rigorous public health framework for management.

In 2015, there were 174 laboratory-confirmed cases of invasive meningococcal disease analysed by the Australian National Neisseria Network. This number was higher than that reported in 2013 and 2014, which were the lowest and second-lowest totals reported, respectively, since inception of the Australian Meningococcal Surveillance Programme in 1994. Probable and laboratory confirmed invasive meningococcal disease (IMD) is notifiable in Australia. There were 182 IMD cases notified to the National Notifiable Diseases Surveillance System in 2015, again, higher than in 2013 and 2014, which were the lowest and second-lowest totals of IMD cases recorded, respectively, by this system. Meningococcal serogrouping was able to be determined for 168/174 (97%) laboratory confirmed IMD cases. Of these, 64.2% (108 cases) were serogroup B infections, the lowest reported since 2003. Further, the number and proportion of cases of serogroup C IMD, (1.2%, 2 cases), was the lowest yet reported. By contrast, in 2015 in Australia, there was a marked increase in the number and proportion of serogroup W IMD (21.4%, 36 cases), and an increase in serogroup Y IMD (13.1%, 22 cases). The number and proportion of IMD cases caused by serogroups W and Y was the highest reported since the inception of the Australian Meningococcal Surveillance Programme in 1994. Molecular typing results were available for 140 of the 174 IMD cases. Of the 31 serogroup W IMD strains that were able to be genotyped, 25/31 (81%) were sequence type (ST)-11, and have the porA antigen encoding gene type P1.5,2, the same genotype as the hypervirulent serogroup W strain of that has been circulating in the United Kingdom and South America since 2009. In 2015, the most common serogroup B porA genotype circulating in Australia was P1.7-2,4. The primary IMD age peak was observed in adults aged 45 years or more, which was the first time that this was noted by the AMSP, whilst secondary disease peaks were observed in those aged 4 years or less, and in adolescents (15-19 years). Serogroup B cases predominated in all jurisdictions and age groups, except for those aged 45 years or over where serogroups W and Y predominated. All IMD isolates tested were susceptible to ceftriaxone and ciprofloxacin. One isolate was resistant to rifampicin. Four isolates were resistant to penicillin. Decreased susceptibility to penicillin was observed in 86% of isolates.

Since 2013, there has been an increase in the number of notified cases of invasive meningococcal disease (IMD) due to serogroup W (MenW) in Australia. In response to this observed increase, the Communicable Diseases Network Australia convened a working group in 2015 to collate and analyse the epidemiology of MenW disease nationally. Enhanced surveillance data collected by jurisdictions were collated and analysed, and whole genome sequencing (WGS) of MenW isolates assessed the genomic relatedness of strains between 2012 and 2015. This report describes that epidemiology. Since 2013, the incidence and proportion of MenW has increased in Australia, rising from an average of 2% of all IMD cases annually (range 0% to 5%) between 1991 and 2012; to 8% (12/149) of cases in 2013, 10% (17/169) in 2014, and 19% (34/182) in 2015. Victoria has been the main affected state, with 50% (17/34) of national cases in 2015. MenW has affected older populations, with a median age between 2003 and 2015 being 44 years. During this period, case fatality was 10.7% (17/159), 2.3 times higher than for all IMD serogroups combined (4.7%, 173/3720). There were 7 deaths due to MenW in 2015 (CFR 21%). WGS has found the majority of Australian isolates cluster within a group of W:P1.5,2:F1-1:ST11 isolates from the United Kingdom and South America, regions where rapid spread and endemic transmission has occurred since 2009. The recent increase in incidence of MenW in Australia is evolving and is being closely monitored. Lessons learned from the international experience will be important in informing the public health response.

The Australian Rotavirus Surveillance Program, together with collaborating laboratories Australia-wide, reports the rotavirus genotypes responsible for the hospitalisation of children with acute gastroenteritis during the period 1 January to 31 December 2015. During the survey period, 1,383 faecal samples were referred for rotavirus G and P genotype analysis, and of these, 1,031 were confirmed as rotavirus positive. A total of 634 specimens had been collected from children under 5 years of age, while 397 were from older children and adults. Genotype analysis of samples from both children and adults revealed that G12P[8] was the dominant genotype in this reporting period, identified in 48.2% of strains nationally. Genotype G3P[8] was the second most common strain nationally, representing 22.8% of samples, followed by G2P[4] and G1P[8] (9% and 8% respectively). G3P[8] was further divided as equine-like G3P[8] (13.2% of all strains) and other wild-type G3P[8] (9.6%). This report highlights the continued predominance of G12P[8] strains as the major cause of disease in this population. Genotype distribution was distinct between jurisdictions using RotaTeq and Rotarix vaccines. Genotype G12P[8] was more common in states using RotaTeq, while equine-like G3P[8] and G2P[4] were more common in the states and territories using Rotarix. This survey highlights the dynamic change in rotavirus genotypes observed since vaccine introduction, including the emergence of a novel equine-like G3P[8] as a major strain. The prolonged dominance of G12P[8] for a 4th consecutive year further illustrates the unexpected trends in the wild type rotaviruses circulating in the Australian population since vaccine introduction.

Bacterial toxin-mediated foodborne outbreaks, such as those caused by Clostridium perfringens, Staphylococcus aureus and Bacillus cereus, are an important and preventable cause of morbidity and mortality. Due to the short incubation period and duration of illness, these outbreaks are often under-reported. This is the first study to describe the epidemiology of bacterial toxin-mediated outbreaks in Australia. Using data collected between 2001 and 2013, we identify high risk groups and risk factors to inform prevention measures. Descriptive analyses of confirmed bacterial toxin-mediated outbreaks between 2001 and 2013 were undertaken using data extracted from the OzFoodNet Outbreak Register, a database of all outbreaks of gastrointestinal disease investigated by public health authorities in Australia. A total of 107 laboratory confirmed bacterial toxin-mediated outbreaks were reported between 2001 and 2013, affecting 2,219 people, including 47 hospitalisations and 13 deaths. Twelve deaths occurred in residents of aged care facilities. Clostridium perfringens was the most commonly reported aetiological agent (81 outbreaks, 76%). The most commonly reported food preparation settings were commercial food preparation services (51 outbreaks, 48%) and aged care facilities (42 outbreaks, 39%). Bacterial toxin outbreaks were rarely associated with food preparation in the home (2 outbreaks, 2%). In all outbreaks, the primary factor contributing to the outbreak was inadequate temperature control of the food. Public health efforts aimed at improving storage and handling practices for pre-cooked and re-heated foods, especially in commercial food preparation services and aged care facilities, could help to reduce the magnitude of bacterial toxin outbreaks.

The Influenza Complications Alert Network (FluCAN) is a sentinel hospital-based surveillance program that operates at sites in all states and territories in Australia. This report summarises the epidemiology of hospitalisations with laboratory-confirmed influenza during the 2015 influenza season. In this observational study, cases were defined as patients admitted to one of the sentinel hospitals with an acute respiratory illness with influenza confirmed by nucleic acid detection. During the period 1 April to 30 October 2015 (the 2015 influenza season), 2,070 patients were admitted with confirmed influenza to one of 17 FluCAN sentinel hospitals. Of these, 46% were elderly (≥ 65 years), 15% were children (< 16 years), 5% were Indigenous Australians, 2.1% were pregnant and 75% had chronic co-morbidities. A high proportion were due to influenza B (51%). There were a large number of hospital admissions detected with confirmed influenza in this national observational surveillance system in 2015 with case numbers similar to that reported in 2014. The national immunisation program is estimated to avert 46% of admissions from confirmed influenza across all at-risk groups, but more complete vaccination coverage in target groups could further reduce influenza admissions by as much as 14%.