4'-Fluorouridine mitigates lethal infection with pandemic human and highly pathogenic avian influenza viruses.

Influenza outbreaks are associated with substantial morbidity, mortality and economic burden. Next generation antivirals are needed to treat seasonal infections and prepare against zoonotic spillover of avian influenza viruses with pandemic potential. Having previously identified oral efficacy of the nucleoside analog 4'-Fluorouridine (4'-FlU, EIDD-2749) against SARS-CoV-2 and respiratory syncytial virus (RSV), we explored activity of the compound against seasonal and highly pathogenic influenza (HPAI) viruses in cell culture, human airway epithelium (HAE) models, and/or two animal models, ferrets and mice, that assess IAV transmission and lethal viral pneumonia, respectively. 4'-FlU inhibited a panel of relevant influenza A and B viruses with nanomolar to sub-micromolar potency in HAE cells. In vitro polymerase assays revealed immediate chain termination of IAV polymerase after 4'-FlU incorporation, in contrast to delayed chain termination of SARS-CoV-2 and RSV polymerase. Once-daily oral treatment of ferrets with 2 mg/kg 4'-FlU initiated 12 hours after infection rapidly stopped virus shedding and prevented transmission to untreated sentinels. Treatment of mice infected with a lethal inoculum of pandemic A/CA/07/2009 (H1N1)pdm09 (pdmCa09) with 4'-FlU alleviated pneumonia. Three doses mediated complete survival when treatment was initiated up to 60 hours after infection, indicating a broad time window for effective intervention. Therapeutic oral 4'-FlU ensured survival of animals infected with HPAI A/VN/12/2003 (H5N1) and of immunocompromised mice infected with pdmCa09. Recoverees were protected against homologous reinfection. This study defines the mechanistic foundation for high sensitivity of influenza viruses to 4'-FlU and supports 4'-FlU as developmental candidate for the treatment of seasonal and pandemic influenza.

Chronic alcohol use primes bronchial cells for altered inflammatory response and barrier dysfunction during SARS-CoV-2 infection.

Alcohol use disorder (AUD) is a significant public health concern and people with AUD are more likely to develop severe acute respiratory distress syndrome (ARDS) in response to respiratory infections. To examine whether AUD was a risk factor for more severe outcome in response to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection, we examined early responses to infection using cultured differentiated bronchial epithelial cells derived from brushings obtained from people with AUD or without AUD. RNA-seq analysis of uninfected cells determined that AUD cells were enriched for expression of epidermal genes as compared with non-AUD cells. Bronchial epithelial cells from patients with AUD showed a significant decrease in barrier function 72 h postinfection, as determined by transepithelial electrical resistance. In contrast, barrier function of non-AUD cells was enhanced 72 h after SARS-CoV-2 infection. AUD cells showed claudin-7 that did not colocalize with zonula occludens-1 (ZO-1), indicative of disorganized tight junctions. However, both AUD and non-AUD cells showed decreased ß-catenin expression following SARS-CoV-2 infection. To determine the impact of AUD on the inflammatory response to SARS-CoV-2 infection, cytokine secretion was measured by multiplex analysis. SARS-CoV-2-infected AUD bronchial cells had enhanced secretion of multiple proinflammatory cytokines including TNFα, IL-1ß, and IFNγ as opposed to non-AUD cells. In contrast, secretion of the barrier-protective cytokines epidermal growth factor (EGF) and granulocyte macrophage-colony stimulating factor (GM-CSF) was enhanced for non-AUD bronchial cells. Taken together, these data support the hypothesis that AUD is a risk factor for COVID-19, where alcohol primes airway epithelial cells for increased inflammation and increased barrier dysfunction and increased inflammation in response to infection by SARS-CoV-2.NEW & NOTEWORTHY Alcohol use disorder (AUD) is a significant risk factor for severe acute respiratory distress syndrome. We found that AUD causes a phenotypic shift in gene expression in human bronchial epithelial cells, enhancing expression of epidermal genes. AUD cells infected with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) had higher levels of proinflammatory cytokine secretion and barrier dysfunction not present in infected non-AUD cells, consistent with increased early COVID-19 severity due to AUD.

Targeted screening for congenital cytomegalovirus: A micro-costing analysis.

AIM: We aimed to determine the cost and potential cost-savings of delivering a targeted congenital cytomegalovirus (cCMV) screening programme through a universal newborn hearing screening (UNHS) programme to detect cCMV-related hearing loss in infants from Victoria, Australia. METHODS: We completed a micro-costing analysis from a health-care perspective using data from a targeted cCMV screening programme piloted between June 2019 and March 2020. The programme involved collection of saliva samples to test for cCMV in infants who: received a 'refer' result on their second newborn hearing screen; were aged 21 days or less; and born at one of four maternity hospitals in Victoria, Australia. All costs to complete targeted cCMV screening were recorded in Australian 2020 dollars. Potential costs and benefits of adding targeted cCMV screening to the pre-existing UNHS programme were compared to when no screening was available up to 18 years to determine the likely cost or cost savings. RESULTS: The cost of adding targeted cCMV screening to Victoria's UNHS is $202 per infant screened. The total cost per positive case identified is $21 456. The overall cost of adding targeted salivary cCMV screening at the point of a second 'refer' result on the UNHS programme in Victoria's four largest hospitals is estimated to be $28 966 for the first year. CONCLUSION: Targeted screening for cCMV provides families the opportunity to detect and, if appropriate, treat cCMV in the first month of life in line with current recommendations. It falls within the range between cost neutral and cost saving.

Diagnosis and analysis of unexplained cases of childhood encephalitis in Australia using metatranscriptomic sequencing.

Encephalitis is most often caused by a variety of infectious agents identified through diagnostic tests utilizing cerebrospinal fluid. We investigated the clinical characteristics and potential aetiological agents of unexplained encephalitis through metagenomic sequencing of residual clinical samples from multiple tissue types and independent clinical review. Forty-three specimens were collected from 18 encephalitis cases with no cause identified by the Australian Childhood Encephalitis study. Samples were subjected to total RNA sequencing ('metatranscriptomics') to determine the presence and abundance of potential pathogens, and to describe the possible aetiologies of unexplained encephalitis. Using this protocol, we identified five RNA and two DNA viruses associated with human infection from both non-sterile and sterile sites, which were confirmed by PCR. These comprised two human rhinoviruses, two human seasonal coronaviruses, two polyomaviruses and one picobirnavirus. Human rhinovirus and seasonal coronaviruses may be responsible for five of the encephalitis cases. Immune-mediated encephalitis was considered likely in six cases and metatranscriptomics did not identify a possible pathogen in these cases. The aetiology remained unknown in nine cases. Our study emphasizes the importance of respiratory viruses in the aetiology of unexplained child encephalitis and suggests that non-central-nervous-system sampling in encephalitis clinical guidelines and protocols could improve the diagnostic yield.

Evaluation of a New Viral Vaccine Vector in Mice and Rhesus Macaques: J Paramyxovirus Expressing Hemagglutinin of Influenza A Virus H5N1.

H5N1, an avian influenza virus, is known to circulate in many Asian countries, such as Bangladesh, China, Cambodia, Indonesia, and Vietnam. The current FDA-approved H5N1 vaccine has a moderate level of efficacy. A safe and effective vaccine is needed to prevent outbreaks of highly pathogenic avian influenza (HPAI) H5N1 in humans. Nonsegmented negative-sense single-stranded viruses (NNSVs) are widely used as a vector to develop vaccines for humans, animals, and poultry. NNSVs stably express foreign genes without integrating with the host genome. J paramyxovirus (JPV) is a nonsegmented negative-strand RNA virus and a member of the proposed genus Jeilongvirus in the family Paramyxoviridae. JPV-specific antibodies have been detected in rodents, bats, humans, and pigs, but the virus is not associated with disease in any species other than mice. JPV replicates in the respiratory tract of mice and efficiently expresses the virus-vectored foreign genes in tissue culture cells. In this work, we explored JPV as a vector for developing an H5N1 vaccine using intranasal delivery. We incorporated hemagglutinin (HA) of H5N1 into the JPV genome by replacing the small hydrophobic (SH) gene to generate a recombinant JPV expressing HA (rJPV-ΔSH-H5). A single intranasal administration of rJPV-ΔSH-H5 protected mice from a lethal HPAI H5N1 challenge. Intranasal vaccination of rJPV-ΔSH-H5 in rhesus macaques elicited antigen-specific humoral and cell-mediated immune responses. This work demonstrates that JPV is a promising vaccine vector. IMPORTANCE A highly pathogenic avian influenza (HPAI) H5N1 outbreak in Southeast Asia destroyed millions of birds. Transmission of H5N1 into humans resulted in deaths in many countries. In this work, we developed a novel H5N1 vaccine candidate using J paramyxovirus (JPV) as a vector and demonstrated that JPV is an efficacious vaccine vector in animals. Nonsegmented negative-sense single-stranded viruses (NNSVs) stably express foreign genes without integrating into the host genome. JPV, an NNSV, replicates efficiently in the respiratory tract and induces robust immune responses.

Matrix Protein 2 Extracellular Domain-Specific Monoclonal Antibodies Are an Effective and Potentially Universal Treatment for Influenza A.

Influenza virus infection causes significant morbidity and mortality worldwide. Humans fail to make a universally protective memory immune response to influenza A. Hemagglutinin and Neuraminidase undergo antigenic drift and shift, resulting in new influenza A strains to which humans are naive. Seasonal vaccines are often ineffective and escape mutants have been reported to all treatments for influenza A. In the absence of a universal influenza A vaccine or treatment, influenza A will remain a significant threat to human health. The extracellular domain of the M2-ion channel (M2e) is an ideal antigenic target for a universal therapeutic agent, as it is highly conserved across influenza A serotypes, has a low mutation rate, and is essential for viral entry and replication. Previous M2e-specific monoclonal antibodies (M2e-MAbs) show protective potential against influenza A, however, they are either strain specific or have limited efficacy. We generated seven murine M2e-MAbs and utilized in vitro and in vivo assays to validate the specificity of our novel M2e-MAbs and to explore the universality of their protective potential. Our data shows our M2e-MAbs bind to M2e peptide, HEK cells expressing the M2 channel, as well as, influenza virions and MDCK-ATL cells infected with influenza viruses of multiple serotypes. Our antibodies significantly protect highly influenza A virus susceptible BALB/c mice from lethal challenge with H1N1 A/PR/8/34, pH1N1 A/CA/07/2009, H5N1 A/Vietnam/1203/2004, and H7N9 A/Anhui/1/2013 by improving survival rates and weight loss. Based on these results, at least four of our seven M2e-MAbs show strong potential as universal influenza A treatments.IMPORTANCE Despite a seasonal vaccine and multiple therapeutic treatments, Influenza A remains a significant threat to human health. The biggest obstacle is producing a vaccine or treatment for influenza A is their universality or efficacy against not only seasonal variances in the influenza virus, but also against all human, avian, and swine serotypes and, therefore, potential pandemic strains. M2e has huge potential as a target for a vaccine or treatment against influenza A. It is the most conserved external protein on the virus. Antibodies against M2e have made it to clinical trials, but not succeeded. Here, we describe novel M2e antibodies produced in mice that are not only protective at low doses, but that we extensively test to determine their universality and found to be cross protective against all strains tested. Additionally, our work begins to elucidate the critical role of isotype for an influenza A monoclonal antibody therapeutic.

Characterizing Emerging Canine H3 Influenza Viruses.

The continual emergence of novel influenza A strains from non-human hosts requires constant vigilance and the need for ongoing research to identify strains that may pose a human public health risk. Since 1999, canine H3 influenza A viruses (CIVs) have caused many thousands or millions of respiratory infections in dogs in the United States. While no human infections with CIVs have been reported to date, these viruses could pose a zoonotic risk. In these studies, the National Institutes of Allergy and Infectious Diseases (NIAID) Centers of Excellence for Influenza Research and Surveillance (CEIRS) network collaboratively demonstrated that CIVs replicated in some primary human cells and transmitted effectively in mammalian models. While people born after 1970 had little or no pre-existing humoral immunity against CIVs, the viruses were sensitive to existing antivirals and we identified a panel of H3 cross-reactive human monoclonal antibodies (hmAbs) that could have prophylactic and/or therapeutic value. Our data predict these CIVs posed a low risk to humans. Importantly, we showed that the CEIRS network could work together to provide basic research information important for characterizing emerging influenza viruses, although there were valuable lessons learned.

Epidemiology and long-term neurological sequelae of childhood herpes simplex CNS infection.

AIM: Herpes simplex CNS infection is a rare but important cause of neurological disability. Long term outcomes after HSV CNS infection in Australia have not yet been fully described. We sought to provide a comprehensive review of HSV CNS infection in children using a retrospective 13-year evaluation of statewide laboratory and clinical records and a parent survey conducted at least one year after the initial infection. METHODS: All positive PCR HSV 1 and 2 results from cerebrospinal fluid (CSF) or brain tissue were obtained from Queensland pathology providers for children aged 0-16 years between 1 January 2005 and 31 December 2017. Clinical data were obtained from patient records and longer-term outcomes via parent survey at least 1 year after initial infection. RESULTS: Forty-three children were identified over the 13-year period, 17 (39.5%) neonates and 26 (60.4%) non-neonates. The annual incidence for HSV CNS infection in Queensland children aged ≤16 years was 0.3/100 000 (95% confidence intervals (CIs): 0.2-0.4) with neonates at highest risk (incidence 2.5/100 000 live births, 95% CI: 1.5-3.9). HSV 1 was the predominant serotype in both neonates and non-neonates (9/17, 52.9% neonates and 19/26, 73.1% non-neonates). Seven (16.3%) children died, five (5/17, 29.4% neonates), directly attributable to HSV CNS infection (all neonates). Twenty-five (58.1%) had neurological morbidity at discharge (9/17 neonates (52.9%) vs. 16/26 (61.5%) non-neonates) and 20/27 (74.1%) reported long-term neurological morbidity at follow-up (5/9 neonates (55.6%) vs. 15/18 non-neonates (83.3%)). Seven children (two neonates and four non-neonates) with long-term neurological sequelae had no neurological morbidity identified at discharge. CONCLUSION: Significant long-term neurologic sequelae were seen in children with HSV CNS infection even in children with no neurological disability identified at discharge from hospital. Careful neurodevelopmental follow-up of all children is recommended.

Feasibility and acceptability of targeted salivary cytomegalovirus screening through universal newborn hearing screening.

AIM: This study aimed to determine the feasibility and parental acceptability of screening for congenital cytomegalovirus (cCMV) through saliva polymerase chain reaction in infants who did not pass their newborn hearing screening. Additionally, the utility (i.e. time to diagnosis and treatment) of this enhanced clinical pathway was evaluated. METHODS: The study was conducted through the Victorian Infant Hearing Screening Programme (VIHSP) across four maternity hospitals in Melbourne, Australia, during June 2019-March 2020. Parents were approached by VIHSP staff about obtaining a test for cytomegalovirus (CMV) at the time of their baby's second positive ('refer') result on the VIHSP screen. Participating parents collected a saliva swab for CMV polymerase chain reaction from their infants. Feasibility was determined by the proportion of 'referred' infants whose parents completed the salivary CMV screening test ≤21 days of life. Acceptability was measured through parent survey. RESULTS: Of 126 eligible families, 96 (76.0%) had salivary screening swabs taken ≤21 days of life. Most families (>92.0%) indicated that screening was acceptable, straightforward and thought testing their baby for cCMV was a good idea. One infant screened positive on day 30, was diagnosed with cCMV via confirmatory testing by day 31 and commenced valganciclovir on day 32. CONCLUSIONS: Obtaining a saliva sample to screen for cCMV in infants who do not pass their newborn hearing screen is feasible and appears acceptable to parents. This targeted cCMV screening method could be an option where mothers are rapidly discharged from hospital, especially in the context of the COVID-19 pandemic.

eLearning significantly improves maternity professionals' knowledge of the congenital cytomegalovirus prevention guidelines.

AIMS: Cytomegalovirus (CMV) is a preventable cause of neurodevelopmental disability. Australian guidelines recommend that pregnant women are informed about CMV to reduce their risk of infection; however, less than 10% of maternity health professionals routinely provide prevention advice. The aim was to develop and evaluate the effectiveness of an eLearning course for midwives to improve knowledge and confidence about CMV. MATERIALS AND METHODS: Participants undertaking the course between March and November 2020 were invited to complete an evaluation questionnaire: before the course (T1), immediately after (T2) and three months post completion (T3). A linear mixed model was used to evaluate change in participant scores; P < 0.05 was considered statistically significant. RESULTS: Midwives (316/363, 87%), midwifery students (29/363, 8%) and nurses (18/363, 5%) participated. At T1 80% indicated they had not received education about CMV. Total adjusted mean scores for questionnaires completed between T1 (n = 363) and T2 (n = 238) increased significantly (from 17.2 to 22.8, P < 0.001). Limited available T3 scores (n = 27) (-1.7, P < 0.001), while lower than T2, remained higher than at T1 (+3.6, P < 0.001). Participants' awareness of CMV information resources improved from 10 to 97% from T1 to T2. Confidence in providing CMV advice increased from 6 to 95% between T1 and T2 (P < 0.001) and was maintained at T3. Almost all (99%) participants indicated they would recommend the course to colleagues. CONCLUSION: Participants who completed the eLearning course had significantly improved knowledge and confidence in providing advice about CMV. Programs targeting other maternity health professionals should be considered, to further support the implementation of the congenital CMV prevention guidelines.

Respiratory Syncytial Virus-Associated Neurologic Complications in Children: A Systematic Review and Aggregated Case Series.

OBJECTIVES: To describe the features and frequency of respiratory syncytial virus (RSV)-associated severe acute neurologic disease in children. STUDY DESIGN: We performed a systematic review of the literature to identify reports of severe acute neurologic complications associated with acute RSV infection in children aged <15 years (PROSPERO Registration CRD42019125722). Main outcomes included neurologic, clinical, and demographic features of cases and the frequency of disease. We aggregated available case data from the published literature and from the Australian Acute Childhood Encephalitis (ACE) study. RESULTS: We identified 87 unique studies from 26 countries describing a spectrum of RSV-associated severe acute neurologic syndromes including proven encephalitis, acute encephalopathy, complex seizures, hyponatremic seizures, and immune-mediated disorders. The frequency of RSV infection in acute childhood encephalitis/encephalopathy was 1.2%-6.5%. We aggregated data from 155 individual cases with RSV-associated severe acute neurologic complications; median age was 11.0 months (IQR 2.0-21.5), most were previously healthy (71/104, 68%). Seizure was the most frequently reported neurologic feature (127/150, 85%). RSV was detected in the central nervous system of 12 cases. Most children recovered (81/122, 66%); however, some reports described partial recovery (33/122, 27%) and death (8/122, 7%). CONCLUSIONS: RSV-associated neurologic complications have been widely reported, but there is substantial heterogeneity in the design and quality of existing studies. The findings from our study have implications for the investigation, management, and prevention of RSV-associated neurologic complications. Further, this systematic review can inform the design of future studies aiming to quantify the burden of childhood RSV-associated neurologic disease.

Antifungal prescribing in neonates: Using national point prevalence survey data from Australia.

We describe contemporary antifungal use in neonates, with point-prevalence survey data from the National Antimicrobial Prescribing Survey across Australian hospitals from 2014 to 2018. There were 247 antifungal prescriptions in 243 neonates in 20 hospitals, median age six days (range 0-27 days). In 219/247 prescriptions (89%) antifungals were prescribed as prophylaxis. Topical (oral) nystatin was the most frequently prescribed in 233/247 prescriptions (94%), followed by fluconazole 11/227 (4%), with substantial variation in dosing for both. Two of 243 neonates (0.8%) had invasive fungal infection. Nystatin use dominates current antifungal prescribing for Australian neonates, in contrast to other countries, and invasive fungal infection is rare. LAY SUMMARY: Novel nationwide surveillance found newborn infants in Australian hospitals commonly receive antifungal medications, mostly oral nystatin. This is given mainly to prevent rather than treat infection, which is rare. There is substantial unexplained variation in dosing of antifungal drugs nationally.

Causes and Clinical Features of Childhood Encephalitis: A Multicenter, Prospective Cohort Study.

BACKGROUND: We aimed to determine the contemporary causes, clinical features, and short-term outcome of encephalitis in Australian children. METHODS: We prospectively identified children (≤14 years of age) admitted with suspected encephalitis at 5 major pediatric hospitals nationally between May 2013 and December 2016 using the Paediatric Active Enhanced Disease Surveillance (PAEDS) Network. A multidisciplinary expert panel reviewed cases and categorized them using published definitions. Confirmed encephalitis cases were categorized into etiologic subgroups. RESULTS: From 526 cases of suspected encephalitis, 287 children met criteria for confirmed encephalitis: 57% (95% confidence interval [CI], 52%-63%) had infectious causes, 10% enterovirus, 10% parechovirus, 8% bacterial meningoencephalitis, 6% influenza, 6% herpes simplex virus (HSV), and 6% Mycoplasma pneumoniae; 25% (95% CI, 20%-30%) had immune-mediated encephalitis, 18% acute disseminated encephalomyelitis, and 6% anti-N-methyl-d-aspartate receptor encephalitis; and 17% (95% CI, 13%-21%) had an unknown cause. Infectious encephalitis occurred in younger children (median age, 1.7 years [interquartile range {IQR}, 0.1-6.9]) compared with immune-mediated encephalitis (median age, 7.6 years [IQR, 4.6-12.4]). Varicella zoster virus encephalitis was infrequent following high vaccination coverage since 2007. Thirteen children (5%) died: 11 with infectious causes (2 influenza; 2 human herpesvirus 6; 2 group B Streptococcus; 2 Streptococcus pneumoniae; 1 HSV; 1 parechovirus; 1 enterovirus) and 2 with no cause identified. Twenty-seven percent (95% CI, 21%-31%) of children showed moderate to severe neurological sequelae at discharge. CONCLUSIONS: Epidemic viral infections predominated as causes of childhood encephalitis in Australia. The leading causes include vaccine-preventable diseases. There were significant differences in age, clinical features, and outcome among leading causes. Mortality or short-term neurological morbidity occurred in one-third of cases.

Antibiotic appropriateness and guideline adherence in hospitalized children: results of a nationwide study.

BACKGROUND: Information on the nature and appropriateness of antibiotic prescribing for children in hospitals is important, but scarce. OBJECTIVES: To analyse antimicrobial prescribing and appropriateness, and guideline adherence, in hospitalized children across Australia. PATIENTS AND METHODS: We analysed data from the National Antimicrobial Prescribing Survey (NAPS) from 2014 to 2017. Surveys were performed in hospital facilities of all types (public and private; major city, regional and remote). Participants were admitted children <18 years old. Risk factors associated with inappropriate prescribing were explored using logistic regression models. RESULTS: Among 6219 prescriptions for 3715 children in 253 facilities, 19.6% of prescriptions were deemed inappropriate. Risk factors for inappropriate prescribing included non-tertiary paediatric hospital admission [OR 1.37 (95% CI 1.20-1.55)] and non-major city hospital location [OR 1.52 (95% CI 1.30-1.77)]. Prescriptions for neonates, immunocompromised children and those admitted to an ICU were less frequently inappropriate. If a restricted antimicrobial was prescribed and not approved, the prescription was more likely to be inappropriate [OR 12.9 (95% CI 8.4-19.8)]. Surgical prophylaxis was inappropriate in 59% of prescriptions. CONCLUSIONS: Inappropriate antimicrobial prescribing in children was linked to specific risk factors identified here, presenting opportunities for targeted interventions to improve prescribing. This information, using a NAPS dataset, allows for analysis of antimicrobial prescribing among different groups of hospitalized children. Further exploration of barriers to appropriate prescribing and facilitators of best practice in this population is recommended.

Early Life Parechovirus Infection Neurodevelopmental Outcomes at 3 Years: A Cohort Study.

OBJECTIVE: To investigate the long-term developmental and behavioral outcomes in an established cohort of children hospitalized as infants with human parechovirus (HPeV) infection and sepsis-like illness. STUDY DESIGN: The HPeV cohort was composed of children 3 years of age after HPeV infection and hospitalization in early infancy that occurred during a well-documented HPeV genotype 3 outbreak in Australia. We assessed neurodevelopmental and behavioral outcomes using the Bayley Scales of Infant and Toddler Development-III and the Child Behavior Checklist. We compared their outcomes with a subsample of healthy control infants drawn from the independently sampled Triple B Pregnancy Cohort Study. RESULTS: Fifty children, with a mean age of 41 months, were followed for 3 years after hospital admission with HPeV infection. There were 47 children whose original illness was fever without source or sepsis-like illness and 3 who had encephalitis. All children in the HPeV cohort showed age-specific development within the population normal range on the Bayley Scales of Infant and Toddler Development-III. There was no difference in developmental attainment compared with 107 healthy control infants after adjusting for measured confounders. The HPeV cohort showed higher average scores on the Child Behavior Checklist and a higher frequency of clinical range scores compared with healthy controls. CONCLUSIONS: Although HPeV sepsis-like illness did not result in neurodevelopmental delay at 3 years of age, it was associated with increased behavioral problems compared with healthy controls. The behavioral problems reached a clinical threshold in a minority of children. Results inform clinical management and planning for children after severe HPeV infection in infancy.

Potential for Low-Pathogenic Avian H7 Influenza A Viruses To Replicate and Cause Disease in a Mammalian Model.

H7 subtype influenza A viruses are widely distributed and have been responsible for human infections and numerous outbreaks in poultry with significant impact. Despite this, the disease-causing potential of the precursor low-pathogenic (LP) H7 viruses from the wild bird reservoir has not been investigated. Our objective was to assess the disease-causing potential of 30 LP H7 viruses isolated from wild avian species in the United States and Canada using the DBA/2J mouse model. Without prior mammalian adaptation, the majority of viruses, 27 (90%), caused mortality in mice. Of these, 17 (56.7%) caused 100% mortality and 24 were of pathogenicity similar to that of A/Anhui/1/2013 (H7N9), which is highly pathogenic in mice. Viruses of duck origin were more pathogenic than those of shorebird origin, as 13 of 18 (72.2%) duck origin viruses caused 100% mortality while 4 of 12 (33.3%) shorebird origin viruses caused 100% mortality, despite there being no difference in mean lung viral titers between the groups. Replication beyond the respiratory tract was also evident, particularly in the heart and brain. Of the 16 viruses studied for fecal shedding, 11 were detected in fecal samples. These viruses exhibited a strong preference for avian-type α2,3-linked sialic acids; however, binding to mammalian-type α2,6-linked sialic acids was also detected. These findings indicate that LP avian H7 influenza A viruses are able to infect and cause disease in mammals without prior adaptation and therefore pose a potential public health risk. IMPORTANCE: Low-pathogenic (LP) avian H7 influenza A viruses are widely distributed in the avian reservoir and are the precursors of numerous outbreaks of highly pathogenic avian influenza viruses in commercial poultry farms. However, unlike highly pathogenic H7 viruses, the disease-causing potential of LP H7 viruses from the wild bird reservoir has not been investigated. To address this, we studied 30 LP avian H7 viruses isolated from wild avian species in the United States and Canada using the DBA/2J mouse model. Surprisingly, the majority of these viruses, 90%, caused mortality in mice without prior mammalian adaptation, and 56.7% caused 100% mortality. There was also evidence of spread beyond the respiratory tract and fecal shedding. Therefore, the disease-causing potential of LP avian H7 influenza A viruses in mammals may be underestimated, and these viruses therefore pose a potential public health risk.

Parechovirus: an important emerging infection in young infants.

Epidemics of human parechovirus (HPeV) causing disease in young children have occurred every 2 years in Australia since 2013. HPeV genotype 3 caused the epidemic from late 2017 to early 2018. Most HPeV infections cause no or mild symptoms including gastroenteritis or influenza-like illness. Characteristically, young infants present with fever, irritability and on occasions a diffuse rash ("red, hot and angry" babies). Severe disease can manifest as meningoencephalitis, seizures or sepsis-like presentations (including septic shock), or less common presentations including signs of surgical abdomen. Testing for HPeV by specific molecular tests is indicated in children younger than 6 months of age with characteristic presentations without another confirmed diagnosis including febrile illnesses with other suggestive features (eg, rash, seizures), sepsis syndromes (including shock), and suspected meningoencephalitis (which may be detected by magnetic resonance imaging only). There are no effective antiviral therapies. Treatment is primarily supportive, including management of complications. Some infants with severe HPeV infection may have adverse neurodevelopment. Follow-up by a paediatrician is recommended.

High prevalence of developmental concern amongst infants at 12 months following hospitalised parechovirus infection.

AIM: The human parechovirus (HPeV) is an increasingly recognised cause of sepsis and central nervous system infection in young infants for which there are limited long-term outcome data. We aimed to assess neurodevelopmental outcome and quality of life in infants following hospitalised HPeV infection. METHODS: This cohort study was a 12-month follow-up of infants who were hospitalised with confirmed HPeV infection at the Sydney Children's Hospitals Network during an outbreak in Sydney in 2013. Telephone interviews were conducted with parents/guardians. We administered standardised questionnaires, including: Ages and Stages Questionnaire (ASQ), Liverpool Outcome Score-follow-up, Pediatric Quality of Life Inventory(PedsQL) Infant scales and Short-Form health survey (SF-12). RESULTS: We followed up 46 of 79 infants (58%) aged between 12 and 16 months who had been hospitalised with HPeV infection; 19% showed significant concern in developmental attainment (ASQ3 score <2 standard deviation below population mean), and 50% showed some concern (<1 standard deviation below mean). ASQ3 developmental outcome was associated with the presence of neurodevelopmental sequelae (lower total Liverpool Outcome Score) and poorer health-related quality of life (HRQOL) in physical functioning (PedsQL physical component score), but not overall HRQOL (total PedsQL score) or parental HRQOL (SF-12 scores). No significant associations were identified between clinical or laboratory features during acute hospitalisation and adverse outcome on ASQ3. CONCLUSIONS: A high proportion of infants show developmental concern at 12-month follow-up post-hospitalisation with HPeV infection. Clinical features during hospitalisation were not associated with adverse outcomes at 12 months. These results suggest that careful follow-up of young infants hospitalised with HPeV disease may be warranted.

The Spectrum and Burden of Influenza-Associated Neurological Disease in Children: Combined Encephalitis and Influenza Sentinel Site Surveillance From Australia, 2013-2015.

Background: There are few longitudinal studies of seasonal influenza-associated neurological disease (IAND) and none from the Southern Hemisphere. Methods: We extracted prospectively acquired Australian surveillance data from 2 studies nested within the Paediatric Active Enhanced Disease Surveillance (PAEDS) network: the Influenza Complications Alert Network (FluCAN) study and the Australian Childhood Encephalitis (ACE) study between 2013 and 2015. We described the clinical features and severity of IAND in children, including influenza-associated encephalitis/encephalopathy (IAE). We calculated the proportion of hospitalized influenza that is associated with IAND and IAE, and incidence of IAE. Results: Over 3 influenza seasons, we identified 54 cases of IAND at 2 tertiary children's hospitals from Australia that accounted for 7.6% of hospitalized influenza. These included 10 cases of IAE (1.4% hospitalized influenza). The mean annual incidence of IAE among Australian children (aged ≤14 years) was 2.8 per 1000000. The spectrum of IAND was broad and included IAE (n = 10) including distinct acute encephalopathy syndromes, simple febrile seizures (n = 14), other seizures (n = 16), acute ataxia (n = 4), and other subacute syndromes (transverse myelitis [n = 1], opsoclonus myoclonus [n = 1]). Two-thirds of children with IAND were aged ≤4 years; less than half had preexisting neurological disease or other risk factors for severe influenza. IAE caused death or neurological morbidity in half of cases. Conclusions: Seasonal influenza is an important cause of acute neurological disease in Australian children. The spectrum of seasonal IAND appears similar to that described during the 2009 H1N1 pandemic. IAE is associated with high morbidity and mortality.