Influenza A/H1N1_09: Australia and New Zealand's winter of discontent

Indian Guidelines on Nebulization Therapy

Inhalational therapy, today, happens to be the mainstay of treatment in obstructive airway diseases (OADs), such as asthma, chronic obstructive pulmonary disease (COPD), and is also in the present, used in a variety of other pulmonary and even non-pulmonary disorders. Hand-held inhalation devices may often be difficult to use, particularly for children, elderly, debilitated or distressed patients. Nebulization therapy emerges as a good option in these cases besides being useful in the home care, emergency room and critical care settings. With so many advancements taking place in nebulizer technology; availability of a plethora of drug formulations for its use, and the widening scope of this therapy; medical practitioners, respiratory therapists, and other health care personnel face the challenge of choosing appropriate inhalation devices and drug formulations, besides their rational application and use in different clinical situations. Adequate maintenance of nebulizer equipment including their disinfection and storage are the other relevant issues requiring guidance. Injudicious and improper use of nebulizers and their poor maintenance can sometimes lead to serious health hazards, nosocomial infections, transmission of infection, and other adverse outcomes. Thus, it is imperative to have a proper national guideline on nebulization practices to bridge the knowledge gaps amongst various health care personnel involved in this practice. It will also serve as an educational and scientific resource for healthcare professionals, as well as promote future research by identifying neglected and ignored areas in this field. Such comprehensive guidelines on this subject have not been available in the country and the only available proper international guidelines were released in 1997 which have not been updated for a noticeably long period of over two decades, though many changes and advancements have taken place in this technology in the recent past. Much of nebulization practices in the present may not be evidence-based and even some of these, the way they are currently used, may be ineffective or even harmful. Recognizing the knowledge deficit and paucity of guidelines on the usage of nebulizers in various settings such as inpatient, out-patient, emergency room, critical care, and domiciliary use in India in a wide variety of indications to standardize nebulization practices and to address many other related issues; National College of Chest Physicians (India), commissioned a National task force consisting of eminent experts in the field of Pulmonary Medicine from different backgrounds and different parts of the country to review the available evidence from the medical literature on the scientific principles and clinical practices of nebulization therapy and to formulate evidence-based guidelines on it. The guideline is based on all possible literature that could be explored with the best available evidence and incorporating expert opinions. To support the guideline with high-quality evidence, a systematic search of the electronic databases was performed to identify the relevant studies, position papers, consensus reports, and recommendations published. Rating of the level of the quality of evidence and the strength of recommendation was done using the GRADE system. Six topics were identified, each given to one group of experts comprising of advisors, chairpersons, convenor and members, and such six groups (A-F) were formed and the consensus recommendations of each group was included as a section in the guidelines (Sections I to VI). The topics included were: A. Introduction, basic principles and technical aspects of nebulization, types of equipment, their choice, use, and maintenance B. Nebulization therapy in obstructive airway diseases C. Nebulization therapy in the intensive care unit D. Use of various drugs (other than bronchodilators and inhaled corticosteroids) by nebulized route and miscellaneous uses of nebulization therapy E. Domiciliary/Home/Maintenance nebulization therapy; public & health care workers education, and F. Nebulization therapy in COVID-19 pandemic and in patients of other contagious viral respiratory infections (included later considering the crisis created due to COVID-19 pandemic). Various issues in different sections have been discussed in the form of questions, followed by point-wise evidence statements based on the existing knowledge, and recommendations have been formulated.

Work-based concerns of Australian frontline healthcare workers during the first wave of the COVID-19 pandemic

OBJECTIVE

This research sought to gauge the extent to which doctors, nurses and paramedics in Australia were concerned about contracting SARS-CoV-2 during the country's first wave of the virus in April 2020.

METHODS

Australian registered doctors, nurses and paramedics (n=580) completed an online questionnaire during April 16-30, 2020 (period immediately following the highest four-week period (first wave) of SARS-CoV-2 confirmed cases in Australia).

RESULTS

During April 2020, two-thirds of participants felt it was likely they would contract SARS-CoV-2 at work. Half the participants suggested Personal Protective Equipment (PPE) supplies were inadequate for them to safely perform their job, with two-thirds suggesting management advised them to alter normal PPE use. One-third of participants suggested they were dissatisfied with their employer's communication of COVID-19 related information. Conclusions and implications for public health: After reports of PPE shortages during Australia's first SARS-CoV-2 wave, and suggestions access to PPE was still limited during Australia's second wave five months later, we must forecast for this and future pandemics ensuring adequate access to PPE for frontline healthcare workers. Further, ensuring consistent and standardised pathways for communication to staff (acknowledging the reality that information may rapidly change) will help alleviate frustration and anxiety.

COVID-19 from the land "Down Under" in an upside-down world: an Australian perspective

We frame the world, which then frames all our seeing, thinking and doing [1]. This is true individually, professionally and at the level of all our institutions. It is a perpetual work in progress that occasionally undergoes a single seismic shift. This is the situation that the world is currently experiencing with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), notwithstanding prior warnings [2, 3].

Australia's approach to the current COVID-19 pandemic has resulted in relative containment of the disease. However, it must be remembered that any defence is only as strong as its weakest link. https://bit.ly/2N2hHy1

Australian Quarantine Policy: From Centralization to Coordination with Mid-Pandemic COVID-19 Shifts

Combining a historical institutionalism approach with institutional isomorphism and punctuated equilibrium, this article analyzes quarantine policy change across 120 years of Australian quarantine history. By anchoring its analysis within specific time periods (the years before the Spanish flu, seven decades of inaction, and multiple post-1997 pandemic updates and responses), the authors highlight when and why policies did or did not change and how the constant push-and-pull between state and Commonwealth institutional ownership altered policy possibilities. The heart of the analysis showcases how Australia's successful COVID-19 response is a unique output of prior quarantine policies, institutional evolution, and mid-pandemic alterations of key national pandemic response plans.

Emerging respiratory infections threatening public health in the Asia-Pacific region: A position paper of the Asian Pacific Society of Respirology

In past decades, we have seen several epidemics of respiratory infections from newly emerging viruses, most of which originated in animals. These emerging infections, including severe acute respiratory syndrome coronavirus (SARS-CoV), Middle East respiratory syndrome coronavirus (MERS-CoV) and the pandemic influenza A(H1N1) and avian influenza (AI) viruses, have seriously threatened global health and the economy. In particular, MERS-CoV and AI A(H7N9) are still causing infections in several areas, and some clustering of cases of A(H5N1) and A(H7N9) may imply future possible pandemics. Additionally, given the inappropriate use of antibiotics and international travel, the spread of carbapenem-resistant Gram-negative bacteria is also a significant concern. These infections with epidemic or pandemic potential present a persistent threat to public health and a huge burden on healthcare services in the Asia-Pacific region. Therefore, to enable efficient infection prevention and control, more effective international surveillance and collaboration systems, in the context of the 'One Health' approach, are necessary.

Effects of pre-existing orthopoxvirus-specific immunity on the performance of Modified Vaccinia virus Ankara-based influenza vaccines

The replication-deficient orthopoxvirus modified vaccinia virus Ankara (MVA) is a promising vaccine vector against various pathogens and has an excellent safety record. However, pre-existing vector-specific immunity is frequently suggested to be a drawback of MVA-based vaccines. To address this issue, mice were vaccinated with MVA-based influenza vaccines in the presence or absence of orthopoxvirus-specific immunity. Importantly, protective efficacy of an MVA-based influenza vaccine against a homologous challenge was not impaired in the presence of orthopoxvirus-specific pre-existing immunity. Nonetheless, orthopoxvirus-specific pre-existing immunity reduced the induction of antigen-specific antibodies under specific conditions and completely prevented induction of antigen-specific T cell responses by rMVA-based vaccination. Notably, antibodies induced by vaccinia virus vaccination, both in mice and humans, were not capable of neutralizing MVA. Thus, when using rMVA-based vaccines it is important to consider the main correlate of protection induced by the vaccine, the vaccine dose and the orthopoxvirus immune status of vaccine recipients.

Modified Vaccinia Virus Ankara Preferentially Targets Antigen Presenting Cells In Vitro, Ex Vivo and In Vivo

Modified Vaccinia virus Ankara (MVA) is a promising vaccine vector with an excellent safety profile. However, despite extensive pre-clinical and clinical testing, surprisingly little is known about the cellular tropism of MVA, especially in relevant animal species. Here, we performed in vitro, ex vivo and in vivo experiments with recombinant MVA expressing green fluorescent protein (rMVA-GFP). In both human peripheral blood mononuclear cells and mouse lung explants, rMVA-GFP predominantly infected antigen presenting cells. Subsequent in vivo experiments performed in mice, ferrets and non-human primates indicated that preferential targeting of dendritic cells and alveolar macrophages was observed after respiratory administration, although subtle differences were observed between the respective animal species. Following intramuscular injection, rMVA-GFP was detected in interdigitating cells between myocytes, but also in myocytes themselves. These data are important in advancing our understanding of the basis for the immunogenicity of MVA-based vaccines and aid rational vaccine design and delivery strategies.

Increased Protein Degradation Improves Influenza Virus Nucleoprotein-Specific CD8+ T Cell Activation In Vitro but Not in C57BL/6 Mice

Due to antigenic drift of influenza viruses, seasonal influenza vaccines need to be updated annually. These vaccines are based on predictions of strains likely to circulate in the next season. However, vaccine efficacy is greatly reduced in the case of a mismatch between circulating and vaccine strains. Furthermore, novel antigenically distinct influenza viruses are introduced into the human population from animal reservoirs occasionally and may cause pandemic outbreaks. To dampen the impact of seasonal and pandemic influenza, vaccines that induce broadly protective and long-lasting immunity are preferred. Because influenza virus-specific CD8⁺ T cells are directed mainly against relatively conserved internal proteins, like nucleoprotein (NP), they are highly cross-reactive and afford protection against infection with antigenically distinct influenza virus strains, so-called heterosubtypic immunity. Here, we used modified vaccinia virus Ankara (MVA) as a vaccine vector for the induction of influenza virus NP-specific CD8⁺ T cells. To optimize the induction of CD8⁺ T cell responses, we made several modifications to NP, aiming at retaining the protein in the cytosol or targeting it to the proteasome. We hypothesized that these strategies would increase antigen processing and presentation and thus improve the induction of CD8⁺ T cell responses. We showed that NP with increased degradation rates improved CD8⁺ T cell activation in vitro if the amount of antigen was limited or if CD8⁺ T cells were of low functional avidity. However, after immunization of C57BL/6 mice, no differences were detected between modified NP and wild-type NP (NPwt), since NPwt already induced optimal CD8⁺ T cell responses.

IMPORTANCE

Due to the continuous antigenic drift of seasonal influenza viruses and the threat of a novel pandemic, there is a great need for the development of novel influenza vaccines that offer broadly protective immunity against multiple subtypes. CD8⁺ T cells can provide immunity against multiple subtypes of influenza viruses by the recognition of relatively conserved internal antigens. In this study, we aimed at optimizing the CD8⁺ T cell response to influenza A virus by making modifications to influenza A virus nucleoprotein (NP) expressed from the modified vaccinia virus Ankara (MVA) vaccine vector. These modifications resulted in increased antigen degradation, thereby producing elevated levels of peptides that can be presented on major histocompatibility complex (MHC) class I molecules to CD8⁺ T cells. Although we were unable to increase the NP-specific immune response in the mouse strain used, this approach may have benefits for vaccine development using less-immunogenic proteins.

Control Measures for Human Respiratory Viral Infection

New viral respiratory pathogens are emerging with increasing frequency and have potentially devastating impacts on the population worldwide. Recent examples of newly emerged threats include severe acute respiratory syndrome coronavirus, the 2009 H1N1 influenza pandemic, and Middle East respiratory syndrome coronavirus. Experiences with these pathogens have shown up major deficiencies in how we deal globally with emerging pathogens and taught us salient lessons in what needs to be addressed for future pandemics. This article reviews the lessons learnt from past experience and current knowledge on the range of measures required to limit the impact of emerging respiratory infections from public health responses down to individual patient management. Key areas of interest are surveillance programs, political limitations on our ability to respond quickly enough to emerging threats, media management, public information dissemination, infection control, prophylaxis, and individual patient management. Respiratory physicians have a crucial role to play in many of these areas and need to be aware of how to respond as new viral pathogens emerge.

Universal influenza vaccines: a realistic option?

The extensive antigenic drift displayed by seasonal influenza viruses and the risk of pandemics caused by newly emerging antigenically distinct influenza A viruses of novel subtypes has raised considerable interest in the development of so-called universal influenza vaccines. We review options for the development of universal flu vaccines and discuss progress that has been made recently.

Influenza and endemic viral pneumonia

Viruses are a common and important cause of severe community-acquired pneumonia, and may lead to severe respiratory disease and admission to the intensive care unit. Influenza is the most common virus associated with severe viral pneumonia, although other important causes include respiratory syncytial virus, adenovirus, metapneumonia virus, and coronaviruses. Viral pneumonias tend to have a seasonal predilection and are often preceded by a typical viral prodrome. This article focuses on severe influenza pneumonia, including the 2009 H1N1 pandemic, and briefly discusses other causes of severe respiratory disease of viral etiology.

H1N1 pandemic: clinical and epidemiologic characteristics of the Canadian pediatric outbreak

Canada was one of the first countries affected by the 2009 influenza H1N1 pandemic with two waves - one from May to June and one from October to December. The 2009 influenza H1N1 pandemic had many unique features when compared with seasonal influenza, including the following: more than half of the affected people were children; asthma was the most significant risk factor for hospital admission; and Aboriginal and pregnant women had a higher risk of hospital admission and complications. Antiviral therapy was widely used but data did not show any effect on the pediatric population. Outbreak spread was possibly promoted from child-child and child-adult contact, and therefore the vaccination campaign targeted the pediatric population and achieved good coverage among young children (57%). Vaccination efficacy was difficult to test because of the vaccination delay. Improvement in models of prevention and treatment are urgently needed to prepare for the possible future pandemics.

Crying wolf? Impact of the H1N1 2009 influenza pandemic on anticipated public response to a future pandemic

OBJECTIVE

To determine changes in public threat perception and anticipated compliance with health-protective behaviours in response to a future pandemic; using data collected before and after the H1N1 2009 influenza pandemic.

DESIGN, SETTING AND PARTICIPANTS

Repeat cross-sectional computer-assisted telephone surveys with representative samples of the general New South Wales population in 2007 (2081 participants) and 2010 (2038 participants).

MAIN OUTCOME MEASURES

Perceived likelihood of a future pandemic in Australia; concern that respondents or their families would be affected; degree of change made to life because of the possibility of a pandemic; and willingness to comply with health-protective behaviours (to be vaccinated, to be isolated if necessary, and to wear a face mask).

RESULTS

In 2007, 14.9% of the general population considered that an influenza pandemic would be highly likely to occur in future; this proportion rose to 42.8% in 2010 (odds ratio [OR], 4.96; 95% CI, 3.99-6.16; P < 0.001). Conversely, in the same period concern that respondents or their families would be directly affected by a future pandemic dropped from 45.5% to 32.5% (OR, 0.57; 95% CI, 0.44-0.74; P < 0.001). Willingness to be vaccinated against influenza in a future pandemic decreased from 75.4% to 64.6% (OR, 0.69; 95% CI, 0.55-0.86; P < 0.001). A general decrease in willingness to be vaccinated was noted across all age groups, most notably for those aged 35-44 years.

CONCLUSIONS

Data collected before and after the H1N1 2009 influenza pandemic indicated significant shifts in public threat perception and anticipated response to a future pandemic. The H1N1 2009 pandemic has altered public perceptions of the probability of a pandemic in the future, but has left the public feeling less vulnerable. Shifts in perception have the potential to reduce future public compliance with health-protective measures, including critical elements of the public health response, such as vaccination.

Public health communication with frontline clinicians during the first wave of the 2009 influenza pandemic

CONTEXT

During public health emergencies, office-based frontline clinicians are critical partners in the detection, treatment, and control of disease. Communication between public health authorities and frontline clinicians is critical, yet public health agencies, medical societies, and healthcare delivery organizations have all called for improvements.

OBJECTIVES

Describe communication processes between public health and frontline clinicians during the first wave of the 2009 novel influenza A(H1N1) pandemic; assess clinicians' use of and knowledge about public health guidance; and assess clinicians' perceptions and preferences about communication during a public health emergency.

DESIGN AND METHODS

During the first wave of the pandemic, we performed a process analysis and surveyed 509 office-based primary care providers in Utah.

SETTING AND PARTICIPANTS

Public health and healthcare leaders from major agencies involved in emergency response in Utah and office-based primary care providers located throughout Utah.

MAIN OUTCOME MEASURE(S)

Communication process and information flow, distribution of e-mails, proportion of clinicians who accessed key Web sites at least weekly, clinicians' knowledge about recent guidance and perception about e-mail load, primary information sources, and qualitative findings from clinician feedback.

RESULTS

The process analysis revealed redundant activities and messaging. The 141 survey respondents (28%) received information from a variety of sources: 68% received information from state public health; almost 100% received information from health care organizations. Only one-third visited a state public health or institutional Web site frequently enough (at least weekly) to obtain updated guidance. Clinicians were knowledgeable about guidance that did not change during the first wave; however, correct knowledge was lower after guidance changed. Clinicians felt overwhelmed by e-mail volume, preferred a single institutional e-mail for clinical guidance, and suggested that new information be concise and clearly identified.

CONCLUSION

: Communication between public health, health care organizations and clinicians was redundant and overwhelming and can be enhanced considering clinician preferences and institutional communication channels.

H1N1-infected Patients in ICU and Their Clinical Outcome

Background:

The swine flu (H1N1) with rapid spread and panic in population is truly global pandemic, affected mainly younger population. There is need to accumulate evidence regarding patient's intensive care parameters for effective management of newer strains of influenza viral infections. Hence an observed retrospective record analysis of confirmed H1N1 patients admitted to intensive care unit (ICU) of a tertiary care centre is done.

Aims:

The study was designed to study the profile and pattern of H1N1 patients admitted to ICU and to study the distribution and associated factors with treatment outcomes.

Materials and Methods:

The demographic, clinical, and laboratory data of 32 (RT-PCR confirmed) H1N1cases were collected and analyzed using Fischer's exact test/paired t test between survivors and nonsurvivors to know their significance. This data included criteria for admission to ICU, type of lung injury, mode of oxygenation, antiviral, and other drugs used.

Results:

There were 11 males and 21 female. Age ranged from 19 to 72 years. Age group of 15–45 years had most cases (78%) and mortality (60%). Most common symptoms were fever and breathlessness (100%). The mean duration of breathlessness was statistically significant (P = 0.037) between two groups. Most common signs were tachycardia and tachypnea. The 75% cases developed acute respiratory distress syndrome (ARDS), of this 16% survived. Among these fatal cases nine were positive for procalcitonin (PCT) (P = 0.006). The rest of 25% developed acute lung injury (ALI) and recovered completely (P = 0.0001).

Conclusion:

Fever and breathlessness were the main presenting complaints. Tachypnea and tachycardia as clinical signs predict development of respiratory complications. Arterial blood gas analysis (ABG) and PaO₂/FiO₂ were important in deciding severity of lung injury and mode of ventilation. ARDS was observed to be the main cause of mortality in this study. Serum PCT level estimation is useful in determining outcome.

A prospective comparison of the epidemiological and clinical characteristics of pandemic (H1N1) 2009 influenza A virus and seasonal influenza A viruses in Guangzhou, South China in 2009

Comparisons of the clinical characteristics of contemporaneous pandemic (H1N1) 2009 influenza A virus (A(H1N1)pdm09)- and seasonal influenza viruses-infected patients are important for both clinical management and epidemiological studies. A prospective multicenter observational study was conducted using a preestablished sentinel surveillance system in Guangzhou, China during 2009. In this study, the clinical presentations of patients with either acute respiratory infection or community-acquired pneumonia were recorded, and nasopharyngeal swab samples were collected for detection of respiratory virus strains using cell cultures or real-time reverse transcription/real-time polymerase chain reaction. Comparisons of the clinical features between A(H1N1)pdm09- and seasonal influenza viruses-infected patients were conducted accordingly. Of the 1,498 patients examined, 265 tested positive for A(H1N1)pdm09, 286 were positive for seasonal influenza A viruses, and 137 for influenza B viruses. The predominant virus was influenza B before the emergence of A(H1N1)pdm09 (epidemiological week [EW] 1-EW 21); then, predominantly non-A(H1N1)pdm09 influenza A and, later, A(H1N1)pdm09, which peaked in EW 46. Compared with the common seasonal influenza-infected patients, A(H1N1)pdm09-infected patients were younger, and had a higher proportion of these patients reported prior contact with infected individuals (P < 0.001, by χ(2) test). However, few significant differences were observed in clinical symptoms and severity among any of the infections caused by the different influenza A strains. Our hospital-based network served as a useful source of information during A(H1N1)pdm09 monitoring. Viral distribution in Guangzhou was characterized by a sharp rise in A(H1N1)pdm09-infected patients in September 2009. Similar to seasonal influenza A-infected cases, A(H1N1)pdm09 cases had a very small proportion of severe cases.

Randomized clinical trial of immunogenicity and safety of a recombinant H1N1/2009 pandemic influenza vaccine containing Advax™ polysaccharide adjuvant

BACKGROUND

Timely vaccine supply is critical during influenza pandemics. A recombinant hemagglutinin (rHA)-based vaccine could overcome production hurdles of egg-based vaccines but has never previously been tested in a real-life pandemic setting. The primary aim was to determine the efficacy of a recombinant pandemic vaccine and whether its immunogenicity could be enhanced by a novel polysaccharide adjuvant (Advax™).

METHODS

281 adults aged 18-70 years were recruited in a randomized, subject and observer blinded, parallel-group study of rHA H1N1/2009 vaccine with or without adjuvant. Immunizations were at 0 and 3 weeks with rHA 3, 11 or 45 μg. Serology and safety was followed for 6 months.

RESULTS

At baseline, only 9.1% of subjects (95% CI: 6.0-13.2) had seroprotective H1N1/2009 titers. Seroconversion rates varied by rHA dose, presence of adjuvant, subject age and number of immunizations. Eighty percent (95% CI: 52-96) of 18-49 year olds who received rHA 45 μg with adjuvant were seroprotected at week 3, representing a 11.1-fold increase in antibody titers from baseline. Advax™ adjuvant increased seroprotection rates by 1.9 times after the first, and 2.5 times after the second, immunization when compared to rHA alone. Seroprotection was sustained at 26 weeks and the vaccine was well tolerated with no safety issues.

CONCLUSIONS

The study confirmed the ability to design, manufacture, and release a recombinant vaccine within a short time from the start of an actual influenza pandemic. Advax™ adjuvant significantly enhanced rHA immunogenicity.

Impacts of rapid flu clinic services at an emergency department during the pandemic flu season

BACKGROUND

We performed an assessment of an independent rapid flu clinic service (RFCS) unit, which was set up outside the emergency department (ED) during the 2009 H1N1 pandemic season. The unit was able to relieve the crowding of regular ambulatory and emergency services.

METHODS

Between August and December 2009, a total of 6,152 patients with influenza-like illness were enrolled in this observational retrospective study. Patients with positive influenza tests were interviewed to evaluate the efficiency of RFCS.

RESULTS

The mean length of stay (LOS) for the RFCS was 50 minutes, which was shorter than the LOS for ambulatory services (1 hour) and regular ED services (3.5 hours). Overall, 88% of patients were satisfied with the RFCS. Of 6,152 patients receiving flu tests, 1,235 (20%) had a positive result. Fever (odds ratio [OR], 4.28, 95% confidence interval [CI]: 3.11-5.89), fever combined with cough and sore throat (OR, 2.52; 95% CI: 2.18-2.92), fever combined with sore throat (OR, 2.42; 95% CI: 2.13-2.75), history of contacting confirmed flu patients within 7 days (OR, 2.40; 95% CI: 2.07-2.78), fever combined with cough (OR, 2.19; 95% CI: 1.92-2.47), sore throat (OR, 2.03, 95% CI: 1.79-2.30); and cough (OR, 1.91, 95% CI: 1.69-2.17) were significantly associated with positive influenza tests.

CONCLUSION

Setting up the RFSC was beneficial to health care facilities during a pandemic flu season.

Differential effects of pandemic (H1N1) 2009 on remote and indigenous groups, Northern Territory, Australia, 2009

TOC summary: Vaccination campaigns and public health responses should focus on high-risk groups.

Pandemic (H1N1) 2009 influenza spread through the Northern Territory, Australia, during June–August 2009. We performed 2 cross-sectional serologic surveys on specimens from Northern Territory residents, with 445 specimens obtained prepandemic and 1,689 specimens postpandemic. Antibody titers were determined by hemagglutination inhibition against reference virus A/California/7/2009 on serum samples collected opportunistically from outpatients. All specimens had data for patients’ gender, age, and address, with patients’ indigenous status determined for 94.1%. Protective immunity (titer >40) was present in 7.6% (95% confidence interval [CI] 5.2%–10.1%) of prepandemic specimens and 19.5% (95% CI 17.6%–21.4%) of postpandemic specimens, giving a population-standardized attack rate of 14.9% (95% CI 11.0%–18.9%). Prepandemic proportion of immune persons was greater with increasing age but did not differ by other demographic characteristics. Postpandemic proportion of immune persons was greater in younger groups and around double in indigenous persons. Postpandemic proportion immune was geographically heterogeneous, particularly among remote-living and indigenous groups.

FluCAN 2009: initial results from sentinel surveillance for adult influenza and pneumonia in eight Australian hospitals

OBJECTIVE

To describe the epidemiology of adult patients hospitalised with influenza or pneumonia during a pandemic season in a sentinel network in Australia.

DESIGN, PARTICIPANTS AND SETTING

Prospective case series of adult hospital admissions to eight acute care general public hospitals (Influenza Complications Alert Network [Flu CAN] sentinel hospitals) in six Australian jurisdictions, 1 July to 4 December 2009.

MAIN OUTCOME MEASURES

Demographic, clinical and outcome measures in patients admitted with laboratory-confirmed pandemic (H1N1) 2009 influenza in the sentinel hospitals compared with data from national notifications and intensive care unit (ICU) surveillance; admissions for influenza and pneumonia over time in each jurisdiction.

RESULTS

During 190 hospital-weeks of observation, there were 538 influenza admissions. Of these, 465 patients (86.4%) had the pandemic strain, representing 9.3% of total admissions with pandemic (H1N1) 2009 influenza (n = 4992) recorded nationally in 2009. Of these patients, 250/465 (53.8%) were women, 67/453 (14.8%) were Indigenous, and the median age was 46 years (interquartile range, 29-58 years). Comorbidities were present in 354/464 patients (76.3%), and 40 were pregnant (30.3% of women aged 15-49 years). FluCAN reported that 102 patients (21.9%) were admitted to ICUs, and of patients admitted to hospital, 26 (5.6%) died. FluCAN results were very similar to national notification data and published ICU admissions data. Of those who were followed to 30 days after discharge, 30 (6.5%) were readmitted. Of 1468 patients hospitalised with pneumonia, 718 (48.9%) were tested for influenza and 163 (11.1%) were co-infected with the pandemic strain.

CONCLUSIONS

Sentinel surveillance systems can provide important and reliable information in a timely fashion and can monitor changes in severity of influenza during a pandemic season.

H1N1: viral pneumonia as a cause of acute respiratory distress syndrome

PURPOSE OF REVIEW

To review the literature on novel swine origin influenza A (H1N1 2009) as a cause of respiratory failure and acute respiratory distress syndrome (ARDS).

RECENT FINDINGS

H1N1 2009 was first recognized as a pathogen in March of 2009, when there was a spike in the number of cases of influenza-like illness leading to severe and at times fatal pneumonia. The etiologic agent was then identified as a novel H1N1 influenza A virus, which subsequent spread rapidly throughout the globe. Most countries reported cases of severe viral pneumonitis requiring intensive care unit (ICU) admission. Severe disease was noted to occur more commonly in younger patients than those typically affected by seasonal influenza and obesity and pregnancy were associated with severe disease. The majority of patients requiring ICU admission met criteria for ARDS and case fatality ratio was estimated at less than 0.5%. Chest radiographs and pathology resembled ARDS and most patients were treated with low tidal volume ventilation, high positive end expiratory pressure and at times, rescue therapies. Available evidence suggests that early antiviral treatment improves outcomes from H1N1 2009.

SUMMARY

H1N1 2009 has emerged as an important cause of ARDS in 2009-2010. Prompt recognition and treatment with antivirals improves outcomes.

Viral pneumonia

About 200 million cases of viral community-acquired pneumonia occur every year-100 million in children and 100 million in adults. Molecular diagnostic tests have greatly increased our understanding of the role of viruses in pneumonia, and findings indicate that the incidence of viral pneumonia has been underestimated. In children, respiratory syncytial virus, rhinovirus, human metapneumovirus, human bocavirus, and parainfluenza viruses are the agents identified most frequently in both developed and developing countries. Dual viral infections are common, and a third of children have evidence of viral-bacterial co-infection. In adults, viruses are the putative causative agents in a third of cases of community-acquired pneumonia, in particular influenza viruses, rhinoviruses, and coronaviruses. Bacteria continue to have a predominant role in adults with pneumonia. Presence of viral epidemics in the community, patient's age, speed of onset of illness, symptoms, biomarkers, radiographic changes, and response to treatment can help differentiate viral from bacterial pneumonia. However, no clinical algorithm exists that will distinguish clearly the cause of pneumonia. No clear consensus has been reached about whether patients with obvious viral community-acquired pneumonia need to be treated with antibiotics. Apart from neuraminidase inhibitors for pneumonia caused by influenza viruses, there is no clear role for use of specific antivirals to treat viral community-acquired pneumonia. Influenza vaccines are the only available specific preventive measures. Further studies are needed to better understand the cause and pathogenesis of community-acquired pneumonia. Furthermore, regional differences in cause of pneumonia should be investigated, in particular to obtain more data from developing countries.

Controlling epidemic viral infection

PURPOSE OF THE REVIEW

Due to their different virulence and infectivity, both severe acute respiratory syndrome (SARS) and H1N1 09 revealed different strengths and weaknesses in our ability to contain new viral threats over the past decade. This review focuses on recent literature around attempts to contain the impact of these two viral epidemics that have refined our approach for the future.

RECENT FINDINGS

Attempts to contain emerging epidemics at the site of origin have so far failed, in part due to resourcing of surveillance. H1N1 09 revealed major problems with rigid pandemic planning and the need for much greater flexibility. Popular attempts to prevent international spread of pandemics have minimal efficacy. Availability of rapid diagnostic tests is critical to optimally managing epidemics and was a major problem with H1N1 09. Healthcare institutions have emerged as a major source of infection.

SUMMARY

The experience with H1N1 09 and SARS has been very useful in informing us of the strengths and weaknesses of our current approach to emerging epidemics. Key messages are a need for improved surveillance, more flexible planning, improved diagnostic testing and retaining a focus on basic hygiene measures.

The impact of pandemic influenza A H1N1 2009 on Australian lung transplant recipients

Influenza A H1N1 2009 led to 189 deaths during the Australian pandemic. Community-acquired respiratory viruses not only can cause prolonged allograft dysfunction in lung transplant recipients but have also been linked to bronchiolitis obliterans syndrome (BOS). We report the impact of the 2009 H1N1 pandemic on Australian lung transplant recipients. An observational study of confirmed H1N1 cases was conducted across five Australian lung transplant programs during the pandemic. An electronic database collected patient demographics, clinical presentation, management and outcomes up to a year follow-up. Twenty-four H1N1 cases (mean age 43 ± 14 years, eight females) were identified, incidence of 3%. Illness severity varied from upper respiratory tract symptoms only in 29% to lung allograft dysfunction (≥10% decline FEV1) in 75% to death in 5 (21%) cases (pre-existing BOS grade 3, n = 4). Treatment with oseltamivir occurred in all but one case confirmed after death, reduced immunosuppression, n = 1, augmented corticosteroid therapy, n = 16, and mechanical/noninvasive ventilation, n = 4. There was BOS grade decline within a year in six cases (32%). In conclusion, Australian lung transplant recipients were variably affected by the H1N1 pandemic mirroring the broader community with significant morbidity and mortality. After initial recovery, a considerable proportion of survivors have demonstrated BOS progression.

We should not be complacent about our population-based public health response to the first influenza pandemic of the 21st century

Background

More than a year after an influenza pandemic was declared in June 2009, the World Health Organization declared the pandemic to be over. Evaluations of the pandemic response are beginning to appear in the public domain.

Discussion

We argue that, despite the enormous effort made to control the pandemic, it is now time to acknowledge that many of the population-based public health interventions may not have been well considered. Prior to the pandemic, there was limited scientific evidence to support border control measures. In particular no border screening measures would have detected prodromal or asymptomatic infections, and asymptomatic infections with pandemic influenza were common. School closures, when they were partial or of short duration, would not have interrupted spread of the virus in school-aged children, the group with the highest rate of infection worldwide. In most countries where they were available, neuraminidase inhibitors were not distributed quickly enough to have had an effect at the population level, although they will have benefited individuals, and prophylaxis within closed communities will have been effective. A pandemic specific vaccine will have protected the people who received it, although in most countries only a small minority was vaccinated, and often a small minority of those most at risk. The pandemic vaccine was generally not available early enough to have influenced the shape of the first pandemic wave and it is likely that any future pandemic vaccine manufactured using current technology will also be available too late, at least in one hemisphere.

Summary

Border screening, school closure, widespread anti-viral prophylaxis and a pandemic-specific vaccine were unlikely to have been effective during a pandemic which was less severe than anticipated in the pandemic plans of many countries. These were cornerstones of the population-based public health response. Similar responses would be even less likely to be effective in a more severe pandemic. We agree with the recommendation from the World Health Organisation that pandemic preparedness plans need review.

The month of July: an early experience with pandemic influenza A (H1N1) in adults with cystic fibrosis

Background

Pandemic Influenza A (H1N1) 2009 is a novel viral infection that emerged in March 2009. This is the first report addressing the clinical course of patients with cystic fibrosis (CF) and H1N1 infection.

Methods

All patients with an influenza-like illness (ILI) attending our adult centre during July 2009 were identified. Baseline respiratory function, nutritional status, approach to management and short-term clinical course were recorded.

Results

Most patients experienced a mild course and were able to be managed with antiviral agents as an outpatient. Robust infection control policies were implemented to limit transmission of H1N1 infection within our CF centre. Patients with severe lung disease, poor baseline nutritional reserve and presenting with more than 48 hours of ILI experienced a more severe course. Prompt antiviral therapy within the first 48 hours of illness may have been important in improving outcomes.

Conclusions

This observational study demonstrates that most adults with CF with H1N1 infection had mild clinical courses and recovered rapidly.