Vaccine microarray patch self-administration: An innovative approach to improve pandemic and routine vaccination rates.

The high-density microprojection array patch (HD-MAP) is a novel vaccine delivery system with potential for self-administered vaccination. HD-MAPs provide an alternative to needle and syringe (N&S) vaccination. Additional advantages could include reduced cold-chain requirements, reduced vaccine dose, reduced vaccine wastage, an alternative for needle phobic patients and elimination of needlestick injuries. The drivers and potential benefits of vaccination by self-administering HD-MAPs are high patient acceptance and preference, higher vaccination rates, speed of roll-out, cost-savings, and reduced sharps and environmental waste. The HD-MAP presents a unique approach in pandemic preparedness and routine vaccination of adults. It could alleviate strain on the healthcare workforce and allows vaccine administration by minimally-trained workers, guardian or subjects themselves. Self-vaccination using HD-MAPs could occur in vaccination hubs with supervision, at home after purchasing at the pharmacy, or direct distribution to in-home settings. As a result, it has the potential to increase vaccine coverage and expand the reach of vaccines, while also reducing labor costs associated with vaccination. Key challenges remain around shifting the paradigm from medical professionals administrating vaccines using N&S to a future of self-administration using HD-MAPs. Greater awareness of HD-MAP technology and improving our understanding of the implementation processes required for adopting this technology, are critical factors underpinning HD-MAP uptake by the public.

The impact of the changing pneumococcal national immunisation program among older Australians.

Australia has a universal infant pneumococcal conjugate vaccination program and until recently a universal pneumococcal polysaccharide vaccine program for non-Indigenous adults aged ≥65 years and Indigenous adults aged ≥50 years. We documented the impacts of infant and adult vaccination programs on the epidemiology of invasive pneumococcal disease (IPD) in Indigenous and non-Indigenous adults. IPD notifications from the National Notifiable Disease Surveillance System were analysed from 2002 to 2017, grouped by age, vaccine serotype group and Indigenous status. Since the universal funding of infant and elderly pneumococcal vaccination programs in January 2005, total IPD decreased by 19% in non-Indigenous adults aged ≥65 years but doubled in Indigenous adults aged ≥50 years. Vaccine uptake was suboptimal in both groups but lower in Indigenous adults. IPD due to the serotypes contained in the pneumococcal conjugate vaccines (PCV) except for serotype 3 declined markedly over the study period but were replaced by non-PCV serotypes. Serotype 3 is currently the most common in older adults. In the populations eligible for the adult 23-valent pneumococcal polysaccharide vaccine (23vPPV) program, IPD rates due to its exclusive serotypes increased to a lower extent than non-vaccine types. In 2017, non-vaccine serotypes accounted for most IPD in the older population eligible for the 23vPPV program, while it's eleven exclusive serotypes accounted for the majority of IPD in younger adults. Infant and adult pneumococcal vaccination programs in Australia have shaped the serotype-specific epidemiology of IPD in older adults. IPD remains a significant health burden for the Indigenous population. Herd immunity impact is clear for PCV serotypes excluding serotype 3 and serotype replacement is evident for non-PCV serotypes. The adult 23vPPV immunisation program appears to have partially curbed replacement with IPD due to its eleven exclusive serotypes, highlighting a potential benefit of increasing adult 23vPPV coverage in Australia.

Immunisation Status of Children with Cerebral Palsy in Rural Bangladesh: Results from the Bangladesh Cerebral Palsy Register (BCPR).

BACKGROUND: Cerebral palsy (CP) is the most common cause of physical disability in childhood, with an estimated 17 million cases worldwide. There is limited data concerning the general health of this population and the immunisation status of children with CP is largely unknown. OBJECTIVE: We aimed to assess the immunisation status of children with CP in rural Bangladesh and determine the predictors of non-immunisation. METHODS: This study is part of the Bangladesh CP Register (BCPR) study; a population based CP register commenced in January 2015 in the Shahjadpur sub-district of Bangladesh. As part of BCPR registration, all children with CP in the catchment area were assessed by a paediatrician and their clinical and immunisation history were collected. RESULTS: Between January and December 2015, 615 children with CP were registered on the BCPR. The median age of the children was 7.5 years, and 38.5% were female. 91.7% of those children had a BCG vaccine scar (as an objective marker for immunisation at birth). However, only 43.2% reported to have received the rubella vaccine during the 2014 national rubella immunisation campaign. Timing of CP diagnosis was found to be an independent predictor for immunisation uptake; those diagnosed before the age of 3 were more likely to have received the rubella vaccine (95% confidence interval [CI] 1.6 - 4.3, odds ratio [OR] 2.6, p <0.0001). CONCLUSIONS: To the best of our knowledge, this is the first paper to use a formal CP register to examine the relationship between CP and immunisation status in a low or middle income country like Bangladesh. Our data suggest that more than half of children with CP in rural Bangladesh did not receive immunisation during a recent national campaign.

The effect of exercise on local and systemic adverse reactions after vaccinations - Outcomes of two randomized controlled trials.

INTRODUCTION: An adverse reaction associated with vaccination is considered to be a key barrier to vaccinate, yet little attention has been given to interventions to reduce their occurrence. Exercise is a behavioural adjuvant which may also influence adverse reactions. Here, two randomized controlled trials are reported, examining the effects of exercise on self-reported adverse reactions following vaccination in adolescents and young adults. METHODS: Study one; 116 adolescents receiving the HPV vaccine were randomly allocated to either Control (n = 56) or Pre-vaccine Exercise (n = 60) group (2015-2016). Exercise consisted of 15-minutes upper body exercise. Study two; 78 young adults receiving the influenza vaccine were randomly allocated to either Control (n = 19), or one of 3 exercise groups: Pre-vaccine Arm (n = 19), Pre-vaccine Leg (n = 20) or Post-vaccine Arm (n = 20) (2017). Exercise included 15-minutes of arm or leg exercises prior to or after vaccination. All participants in both studies completed an adverse events diary for seven-days post-vaccination. RESULTS: Study one; Reported days of tenderness in female adolescents that exercised were significantly lower than control (p = 0.032), with a similar trend in reported days of pain (p = 0.050). Furthermore, days of feeling ill (p = 0.070) and reduced appetite (p = 0.067) were found to be lower with exercise, although not significant. Overall, female adolescents reported significantly more days of pain (p = 0.003), tenderness (p < 0.001), swelling (p = 0.011), and feeling ill (p = 0.0040). Study two; Exercise groups reported reduced days of swelling (p = 0.018), fever (p = 0.013), and lowered appetite (p = 0.011) across both genders. Furthermore, females reported reduced days of medication use with exercise (p = 0.034), and a trend toward reduced days of swelling (p = 0.052). DISCUSSION: In two separate trials, a short bout of exercise reduced reported adverse reactions after vaccinations for local and systemic adverse reactions. Gender differences in reported local and systemic adverse reactions were more evident among adolescents than young adults. These findings support the need for further work to examine the potential benefit of exercise in improving vaccination procedures.

Effect of Tdap upon antibody response to meningococcal polysaccharide when administered before, with or after the quadrivalent meningococcal TT-conjugate vaccine (coadministered with the 13-valent pneumococcal CRM197-conjugate vaccine) in adult Hajj pilgrims: A randomised controlled trial.

Hajj pilgrims are susceptible to several serious infections and are required to receive multiple vaccinations. Polysaccharide-protein conjugate vaccines contain carrier proteins such as tetanus toxoid (TT), diphtheria toxoid or a mutant of diphtheria toxoid (CRM197). These carrier proteins may interact with other conjugate or combination vaccines containing tetanus or diphtheria on concurrent or sequential administration. We examined the immune interaction of separate and concomitant administration of a tetanus/diphtheria/acellular pertussis (Tdap) vaccine with a TT-conjugated quadrivalent meningococcal vaccine (MCV4) (coadministered with 13-valent pneumococcal CRM197-conjugate vaccine [PCV13]) in adult Australian pilgrims before attending Hajj in 2015. We randomly assigned each participant to one of three vaccination schedules. Group 1 received Tdap 3-4 weeks before receiving MCV4 coadministered with PCV13. Group 2 received all three vaccines concomitantly. Group 3 received MCV4 and PCV13 3-4 weeks before Tdap. Blood samples were collected at baseline, at each vaccination visit and 3-4 weeks after vaccination and tested for response to meningococcal serogroups C, W and Y using a serum bactericidal antibody (rSBA) assay with baby rabbit complement, and to diphtheria and tetanus toxoid, measuring IgG antibodies by ELISA. Participants completed symptom diaries after each vaccination. A total of 166 participants aged 18-64 (median 42) years were recruited, of whom 160 completed the study. Compared to the other groups, Group 1 (given Tdap first) had significantly lower proportion of subjects achieving a ≥4-fold rise in rSBA for serogroup W. No difference was detected across the three groups in achieving protection threshold (rSBA ≥8 post vaccination) or SBA geometric mean titre (GMT) post vaccination. Group 3, which was given MCV4/PCV13 first, had high levels of antibody against diphtheria and tetanus than the other groups, when tested prior to receipt of Tdap; Only the anti-tetanus responses remained significantly higher after Tdap administration. No serious adverse events were reported. In conclusion, when multiple vaccination is required for Hajj pilgrims, administering Tdap concurrently with MCV4/PCV13 produces adequate immune responses, and avoids meningococcal immune interference, in the convenience of a single consultation. However, giving Tdap 3-4 weeks after MCV4/PCV13 has the advantage of an enhanced tetanus toxoid response. The trial is Trials Registry (ANZCTR): ACTRN12613000536763.

The effect of exercise on vaccine-related pain, anxiety and fear during HPV vaccinations in adolescents.

INTRODUCTION: With increased school-based vaccinations for improved coverage rates and practicality, the World Health Organization (WHO) recently endorsed research to identify possible interventions to reduce vaccine-related pain in mass clinical and school-based settings. In particular, the lack of research in adolescents indicate a particular need in this population. Acute exercise has analgesic effects and has been used as a behavioural adjuvant to vaccination. Here, we examine the effect of exercise on vaccine-related pain, anxiety and fear in adolescents, during a school-based program for HPV vaccinations. METHODS: 116 students (Female: 61, Male: 55) aged 11-13 years were randomly allocated to either an Exercise (n = 60) or Control (n = 56) group. All participants completed demographic and Trait-anxiety questionnaires prior to receiving the vaccine according to usual care. The Exercise group also performed upper body exercise for 15 min prior to receiving the vaccine. Immediately after the vaccine administration, all participants reported on pain, anxiety and fear at the time of receiving the vaccine. RESULTS: Female adolescents in the Exercise group reported significantly less pain (3.64; 95% CI, 2.98-4.30) than Controls (4.58; 95% CI, 3.96-5.19; p = 0.04). Further, females reported greater pain and anxiety than males in the Control group but not the Exercise group. CONCLUSION: This study supports the use of exercise prior to vaccine administration, especially in female adolescents who are particularly vulnerable to negative experiences during vaccination procedures. Furthermore, the ease of application, as well as the benefit of exercise, provides support for the use of simple exercise prior to vaccination in mass vaccination settings. Clinical trial registry: ANZCTR, ACTRN12614001185651.

Influenza hospitalizations in Australian children.

Australia's National Immunisation Program (NIP) provides free influenza vaccination for children at high risk of severe influenza; a pilot-funded programme for vaccine in all children aged 6 months to <5 years in one of eight states, has seen poor vaccine impact, related to recent vaccine safety concerns. This retrospective review examined influenza hospitalizations in children aged <16 years from three seasons (2011-2013) at two paediatric hospitals on opposite sides of the country. Comparisons of this cohort were made with state-based data on influenza-coded hospitalizations and national immunization register data on population-level immunization coverage. Of 740 hospitalizations, the majority were aged <5 years (476/740, 64%), and a substantial proportion (57%) involved healthy children, not currently funded for influenza vaccine. Intensive care unit admission occurred in 8·5%, and 1·5% of all children developed encephalitis. Use of antiviral therapy was uncommon (20·5%) and decreasing. Of those hospitalized, only 5·0% of at-risk children, who are currently eligible for free vaccine, and 0·7% of healthy children were vaccinated prior to hospitalization. This was consistent with low population-wide estimates of influenza vaccine uptake. It highlights the need to examine alternative strategies, such as universally funded paediatric influenza vaccination, to address disease burden in Australian children.

Effect of Tdap when administered before, with or after the 13-valent pneumococcal conjugate vaccine (coadministered with the quadrivalent meningococcal conjugate vaccine) in adults: A randomised controlled trial.

Sequential or co-administration of vaccines has potential to alter the immune response to any of the antigens. Existing literature suggests that prior immunisation of tetanus/diphtheria-containing vaccines can either enhance or suppress immune response to conjugate pneumococcal or meningococcal vaccines. We examined this interaction among adult Australian travellers before attending the Hajj pilgrimage 2014. We also investigated tolerability of these vaccines separately and concomitantly. We randomly assigned each participant to one of three vaccination schedules. Group A received adult tetanus, diphtheria and acellular pertussis vaccine (Tdap) 3-4weeks before receiving CRM197-conjugated 13-valent pneumococcal vaccine (PCV13) and CRM197-conjugated quadrivalent meningococcal vaccine (MCV4). Group B received all three vaccines on one day. Group C received PCV13 and MCV4 3-4weeks before Tdap. Blood samples collected at baseline, each vaccination visit and 3-4weeks after vaccination were tested using the pneumococcal opsonophagocytic assay (OPA) and by ELISA for diphtheria and tetanus antibodies. Funding for meningococcal serology was not available. Participants completed symptom diaries after each vaccination. A total of 111 participants aged 18-64 (median 40) years were recruited. No statistically significant difference was detected across the three groups in achieving OPA titre ⩾1:8 post vaccination. However, compared to other groups, Group A had a statistically significant lower number of subjects achieving ⩾4-fold rise in serotype 3, and also significantly lower geometric mean titres (GMTs) to six (of 13) pneumococcal serotypes (3, 5, 18C, 4, 19A and 9V). Group C (given prior PCV13 and MVC4) had statistically significant higher pre-Tdap geometric mean concentration (GMC) of anti-diphtheria IgG; however, there was no difference across the three groups following Tdap. Anti-tetanus IgG GMCs were similar across the groups before and after Tdap. No serious adverse events were reported. In conclusion, Tdap vaccination 3-4weeks before concomitant administration of PCV13 and MCV4 significantly reduced the antibody response to six of the 13 pneumococcal serotypes in adults. The trial is registered at the Australian New Zealand Clinical Trials Registry (ANZCTR): ACTRN12613000536763.

Meningococcal disease epidemiology in Australia 10 years after implementation of a national conjugate meningococcal C immunization programme.

Australia implemented conjugate meningococcal C immunization in 2003 with a single scheduled dose at age 12 months and catch-up for individuals aged 2-19 years. Several countries have recently added one or more booster doses to their programmes to maintain disease control. Australian disease surveillance and vaccine coverage data were used to assess longer term vaccine coverage and impact on invasive serogroup C disease incidence and mortality, and review vaccine failures. Coverage was 93% in 1-year-olds and 70% for catch-up cohorts. In 10 years, after adjusting for changes in diagnostic practices, population invasive serogroup C incidence declined 96% (95% confidence interval 94-98) to 0·4 and 0·6 cases/million in vaccinated and unvaccinated cohorts, respectively. Only three serogroup C deaths occurred in 2010-2012 vs. 68 in 2000-2002. Four (<1/million doses) confirmed vaccine failures were identified in 10 years with no increasing trend. Despite published evidence of waning antibody over time, an ongoing single dose of meningococcal C conjugate vaccine in the second year of life following widespread catch-up has resulted in near elimination of serogroup C disease in all age groups without evidence of vaccine failures in the first decade since introduction. Concurrently, serogroup B incidence declined independently by 55%.

Pilot surveillance for childhood encephalitis in Australia using the Paediatric Active Enhanced Disease Surveillance (PAEDS) network.

We aimed to assess the performance of active surveillance for hospitalized childhood encephalitis in New South Wales (NSW) using the Paediatric Active Enhanced Disease Surveillance (PAEDS) network to inform methodology for the nationwide Australian childhood encephalitis (ACE) study. We piloted active surveillance for suspected encephalitis from May to December 2013 at the Children's Hospital at Westmead, Sydney, NSW. Cases were ascertained using four screening methods: weekday nurse screening of admission records (PAEDS), cerebrospinal fluid (CSF) microscopy records, magnetic resonance imaging (MRI) reports, and pharmacy dispensing records. Comprehensive clinical data were prospectively collected on consented participants and subsequently reviewed by an expert panel. Cases were categorized as confirmed encephalitis or 'not encephalitis'; encephalitis cases were sub-categorized as infectious, immune-mediated or unknown. We performed an ICD-10 diagnostic code audit of hospitalizations for the pilot period. We compared case ascertainment in the four screening methods and with the ICD code audit. Forty-eight cases of suspected encephalitis were identified by one or more methods. PAEDS was the most efficient mechanism (yield 34%), followed by MRI, CSF, and pharmacy audits (yield 14%, 12%, and 7% respectively). Twenty-five cases met the criteria for confirmed encephalitis. PAEDS was the most sensitive of the mechanisms for confirmed encephalitis (92%) with a positive predictive value (PPV) of 72%. The ICD audit was moderately sensitive (64%) but poorly specific (Sp 9%, PPV 14%). Of the 25 confirmed encephalitis cases, 19 (76%) were sub-categorized as infectious, three (12%) were immune-mediated, and three (12%) were 'unknown'. We identified encephalitis cases associated with two infectious disease outbreaks (enterovirus 71, parechovirus 3). PAEDS is an efficient, sensitive and accurate surveillance mechanism for detecting cases of childhood encephalitis including those associated with emerging infectious diseases. Active surveillance significantly increases the ascertainment of encephalitis cases compared with passive approaches.

Systematic review of fever, febrile convulsions and serious adverse events following administration of inactivated trivalent influenza vaccines in children.

In 2010, increased febrile convulsions (FC) occurred after administration of inactivated trivalent influenza vaccine (TIV) in Australia. We systematically reviewed the rates of fever, FC and serious adverse events (SAEs) after TIV, focussing on published and unpublished clinical trial data from 2005 to 2012, and performed meta-analysis of fever rates. From 4,372 records in electronic databases, 18 randomised controlled trials (RCTs), 14 non-randomised clinical trials, six observational studies and 12 registered trials (five RCTs and seven non-randomised) were identified. In published RCTs, fever ≥ 38 °C rates after first dose of non-adjuvanted TIV were 6.7% and 6.9% for children aged 6­35 months and ≥ 3 years, respectively. Analysis of RCTs by vaccine manufacturer showed pooled fever estimates up to 5.1% with Sanofi or GlaxoSmithKline vaccines; bioCSL vaccines were used in two non-randomised clinical trials and one unpublished RCT and were associated with fever in 22.5­37.1% for children aged 6­35 months. In RCTs, FCs occurred at a rate of 1.1 per 1,000 vaccinated children. While most TIVs induced acceptably low fever rates, bioCSL influenza vaccines were associated with much higher rates of fever in young children. Future standardised study methodology and access to individual level data would be illuminating.

Consensus guidelines for the investigation and management of encephalitis in adults and children in Australia and New Zealand.

Encephalitis is a complex neurological syndrome caused by inflammation of the brain parenchyma. The management of encephalitis is challenging because: the differential diagnosis of encephalopathy is broad; there is often rapid disease progression; it often requires intensive supportive management; and there are many aetiologic agents for which there is no definitive treatment. Patients with possible meningoencephalitis are often encountered in the emergency care environment where clinicians must consider differential diagnoses, perform appropriate investigations and initiate empiric antimicrobials. For patients who require admission to hospital and in whom encephalitis is likely, a staged approach to investigation and management is preferred with the potential involvement of multiple medical specialties. Key considerations in the investigation and management of patients with encephalitis addressed in this guideline include: Which first-line investigations should be performed?; Which aetiologies should be considered possible based on clinical features, risk factors and radiological features?; What tests should be arranged in order to diagnose the common causes of encephalitis?; When to consider empiric antimicrobials and immune modulatory therapies?; and What is the role of brain biopsy?

Australian Hajj pilgrims' knowledge, attitude and perception about Ebola, November 2014 to February 2015.

Upon return from Hajj 2014, 150 Australian pilgrims were interviewed about their understanding of the Ebola epidemic. Most (89%, 134/150) knew of the epidemic before travelling and 60% (80/134) of those knew Ebola transmits through body fluids. Pilgrims who received pre-travel health advice were more conscious of Ebola (69% vs 31%, p = 0.01) and adhered better to hand hygiene after touching an ill person (68% vs 31%, p < 0.01). Mass media was the main information source (78%).

Community preparedness for highly pathogenic Avian influenza on Bali and Lombok, Indonesia.

INTRODUCTION: The Asia-Pacific region is the likeliest location for the next significant outbreak of highly pathogenic avian influenza (HPAI). Indonesia has experienced HPAI H5N1 outbreaks in poultry and humans each year since 2003 and has had the highest case fatality rate for human cases. The purposes of this study were to capture the knowledge of avian influenza and of poultry-raising practices in two regions of Indonesia and to evaluate the impact and extent of activities undertaken to 2010 through the National Strategic Plan for Avian Influenza Control at the village level. METHODS: A combination of quantitative and qualitative methods was used to investigate the multiple influences on behaviours, decisions and actions taken by poultry-raising households, and by villages and communities, regarding the threat of HPAI. Between June 2010 and May 2011 a structured survey of 400 households was conducted on Lombok and of 402 on Bali, inviting Sector 3 (small-scale independent commercial poultry farms) and Sector 4 (village household) poultry raisers to participate. Focus groups and in-depth interviews were convened with key stakeholders, including livestock and animal health and public health officials, community leaders and villagers. RESULTS: From the focus group and in-depth interviews, it appears that the flow of information through the national HPAI control program has been efficient at the top levels (from national to provincial, then to districts and subdistricts). However, these findings show that effective transmission of information from subdistrict to rural village level and from village leaders to community members has been limited. The degree of community preparedness for HPAI on Bali and Lombok appears minimal. Knowledge of government activities was more extensive at Bali sites, while only limited government programs and activities occurred at the village level on Lombok. Activities conducted by government agencies from provincial to village level were limited in scope and need to be further developed to ensure safe poultry-handling practices and biosecurity measures. On both Bali and Lombok, community respondents knew the signs and symptoms of sick birds but did not differentiate well between HPAI and other bird diseases. On both islands, more than 60% of respondents were reluctant to report sudden deaths of poultry. The lack of a government compensation program for destroyed flocks contributed to this unwillingness to report. CONCLUSIONS: While the Indonesian government's planning efforts for HPAI are commendable, the plan has not been effective, as it depends on the cooperative actions of people with small rural farms who have not been consulted in the development of the plan, have not been adequately instructed on the nature of the plan, and perceive no benefits to themselves from prevention efforts. Context-appropriate mechanisms for communicating zoonotic risk and options for risk mitigation that do not result in net loss to poor households are also needed.

Nosocomial vs community-acquired pandemic influenza A (H1N1) 2009: a nested case-control study.

BACKGROUND: The characteristics of nosocomial influenza in children are not well described. AIM: To compare the characteristics of nosocomial and community-acquired pandemic influenza A (H1N1) 2009 (pH1N1) in Australian children. METHODS: In a nested case-control study, the clinical and epidemiological features of nosocomial vs community-acquired pH1N1 were compared among hospitalized children aged <15 years in six paediatric hospitals in Australia between 1 June and 30 September 2009. FINDINGS: Of 506 hospitalized children with pH1N1, 47 (9.3%) were of nosocomial origin. These 47 cases were compared with 141 gender- and age-matched controls. Cases had a significantly higher proportion of underlying medical conditions compared with controls (81% vs 42%, P < 0.001), and were more likely to be exposed to household smokers (36% vs 20%, P = 0.02). Fewer children with nosocomial influenza presented with classical symptoms of influenza, including subjective fever and lethargy. A higher proportion of children with nosocomial influenza received treatment with oseltamivir (77% vs 43%, P < 0.001), and they required a longer stay in hospital following the onset of influenza (mean 8.5 days vs 4.5 days, P = 0.006). Three children (2%) in the community-acquired group died of pH1N1, but there were no deaths in the nosocomial group. CONCLUSION: This study shows that children with pre-existing diseases and those who are exposed to household smokers are more susceptible to nosocomial pH1N1. They may have 'occult presentation' of influenza, but their course of illness is not markedly different from that of children with community-acquired influenza.

Frequency of oseltamivir resistance in Sydney, during the Newcastle outbreak of community transmitted oseltamivir-resistant influenza A(H1N1)pdm09 virus, Australia, June to August 2011.

Although oseltamivir-resistant pandemic influenza A(H1N1)pdm09 is uncommon in immunocompetent individuals, a recent report from Newcastle, Australia, showed the first sustained community spread, from June to August 2011, of oseltamivir-resistant influenza A(H1N1)pdm09 virus carrying the H275Y neuraminidase (NA) mutation. To determine the frequency and the extent of this viral variant spread in the nearest major city to Newcastle, we performed a sequencebased genotypic assessment on samples from 143 oseltamivir untreated and 23 oseltamivir post-treatment individuals with influenza collected contemporaneously in Sydney, 120 km southwest of Newcastle. The detection of two of 143 (1.4%) community-derived samples containing H275Y suggests a low prevalence of oseltamivir-resistant influenza A(H1N1)pdm09 virus in the general community and no convincing evidence of spread of the NA H275Y-bearing influenza A(H1N1)pdm09 virus. In oseltamivir treated patients, oseltamivir-resistant influenza A(H1N1)pdm09 virus continue to emerge with three of 23 (13%) post-treatment samples containing the H275Y mutation. The observation of signature mutations and distinct phylogenetic relationship in full-length sequences of haemagglutinin and neuraminidase genes derived from 2011 strains against 2009 strains indicates continued genetic evolution and antigenic drift of the influenza A(H1N1)pdm09 viruses circulating in Australia.

Characteristics of a widespread community cluster of H275Y oseltamivir-resistant A(H1N1)pdm09 influenza in Australia.

BACKGROUND: Oseltamivir resistance in A(H1N1)pdm09 influenza is rare, particularly in untreated community cases. Sustained community transmission has not previously been reported. METHODS: Influenza specimens from the Asia-Pacific region were collected through sentinel surveillance, hospital, and general practitioner networks. Clinical and epidemiological information was collected on patients infected with oseltamivir-resistant viruses. RESULTS: Twenty-nine (15%) of 191 A(H1N1)pdm09 viruses collected between May and September 2011 from Hunter New England (HNE), Australia, contained the H275Y neuraminidase substitution responsible for oseltamivir resistance. Only 1 patient had received oseltamivir before specimen collection. The resistant strains were genetically very closely related, suggesting the spread of a single variant. Ninety percent of cases lived within 50 kilometers. Three genetically similar oseltamivir-resistant variants were detected outside of HNE, including 1 strain from Perth, approximately 4000 kilometers away. Computational analysis predicted that neuraminidase substitutions V241I, N369K, and N386S in these viruses may offset the destabilizing effect of the H275Y substitution. CONCLUSIONS: This cluster represents the first widespread community transmission of H275Y oseltamivir-resistant A(H1N1)pdm09 influenza. These cases and data on potential permissive mutations suggest that currently circulating A(H1N1)pdm09 viruses retain viral fitness in the presence of the H275Y mutation and that widespread emergence of oseltamivir-resistant strains may now be more likely.

Intussusception following rotavirus vaccine administration: post-marketing surveillance in the National Immunization Program in Australia.

INTRODUCTION: In Australia, post-marketing surveillance for intussusception following vaccination commenced with funding of RotaTeq(®) and Rotarix(®) vaccines under the National Immunization Program (NIP) in July 2007. METHODS: Two active surveillance mechanisms (hospital-based case ascertainment and monthly reports from paediatricians) identified intussusception cases between 1st July 2007 and 31st December 2008 in four states. Linkage to vaccination records identified cases occurring within 1-7 and 1-21 days of rotavirus vaccination. Expected cases within the post-vaccination windows were calculated by applying rates of intussusception from national hospitalisation data over 6 years (mid-2000 to mid-2006), by age and state, to numbers vaccinated (by dose) according to the Australian Childhood Immunization Register. RESULTS: Combining exposure windows associated with all doses of rotavirus vaccine from 1 to 9 months of age, there was no evidence of an increased risk of intussusception following vaccination for either vaccine. However, in infants 1 to <3 months of age, there was suggestive evidence of excess intussusception cases 1-7 and 1-21 days following dose 1 (1-7 days: RotaTeq(®) relative risk (RR)=5.3, 95% confidence interval [CI] 1.1,15.4; Rotarix(®) RR 3.5, 95% CI 0.7,10.1; 1-21 days: RotaTeq(®) RR 3.5, 95% CI 1.3, 7.6; Rotarix(®)RR 1.5, 95% CI 0.4, 3.9). There was no evidence that clinical outcome of intussusception occurring within 21 days of rotavirus vaccination differed from that in cases occurring later post-vaccination. CONCLUSION: Although we found no overall increase in intussusception following receipt of rotavirus vaccine, there was some evidence of an elevated risk following the first dose of both vaccines. Larger population-based studies using linked databases are required to provide more definitive evidence.