The Impact of Pneumococcal Vaccination on Bacterial and Viral Pneumonia in Western Australian Children: Record Linkage Cohort Study of 469589 Births, 1996-2012

Interactions between respiratory syncytial virus and Streptococcus pneumoniae in the pathogenesis of childhood respiratory infections: a systematic review

Lower respiratory tract infections, commonly caused by respiratory syncytial virus (RSV) or Streptococcus pneumoniae (pneumococcus), pose a substantial global health burden, especially in children younger than 5 years of age. A deeper understanding of the relationship between RSV and pneumococcus would aid the development of health-care approaches to disease prevention and management. We completed a systematic review to identify and assess evidence pertaining to the relationship between RSV and pneumococcus in the pathogenesis of childhood respiratory infections. We found mechanistic evidence for direct pathogen-pathogen interactions and for indirect interactions involving host modulation. We found a strong seasonal epidemiological association between these two pathogens, which was recently confirmed by a parallel decrease and a subsequent resurgence of both RSV and pneumococcus-associated disease during the COVID-19 pandemic. Importantly, we found that pneumococcal vaccination was associated with reduced RSV hospitalisations in infants, further supporting the relevance of their interaction in modulating severe disease. Overall evidence supports a broad biological and clinical interaction between pneumococcus and RSV in the pathogenesis of childhood respiratory infections. We hypothesise that the implementation of next-generation pneumococcal and RSV vaccines and monoclonal antibodies targeting RSV will act synergistically to reduce global morbidity and mortality related to childhood respiratory infections.

Impact of pneumococcal conjugate vaccine 13 introduction on severe lower respiratory tract infections associated with respiratory syncytial virus or influenza virus in hospitalized children in Ulaanbaatar, Mongolia

Objectives

Limited data indicate a beneficial effect of pneumococcal conjugate vaccines (PCVs) on respiratory syncytial virus (RSV) and influenza infections in young children. We evaluated the impact of 13-valent PCV (PCV13) introduction on the incidence of severe lower respiratory tract infections (LRTIs) associated with RSV or influenza in hospitalized children.

Methods

Our study was restricted to children aged <2 years with arterial oxygen saturation <93% and children with radiologically confirmed pneumonia nested in a pneumonia surveillance project in four districts of Ulaanbaatar city, Mongolia. We tested nasopharyngeal swabs collected on admission for RSV and influenza using quantitative reverse transcription-polymerase chain reaction. The impact of PCV13 on the incidence of LRTI outcomes associated with RSV or with influenza for the period April 2015-March 2020 was estimated. Incidence rate ratios comparing pre- and post-vaccine periods were estimated for each outcome for each district using negative binomial models and for all districts combined with a mixed-effects negative binomial model. Adjusted models accounted for seasonality. Sensitivity analyses were conducted to assess the robustness of our findings.

Results

Among 5577 tested cases, the adjusted incidence rate ratios showed a trend toward a reduction in RSV-associated outcomes: all LRTIs (0.77, 95% confidence interval [CI] 0.44-1.36), severe LRTIs (0.88, 95% CI 0.48-1.62), very severe LRTIs (0.76, 95% CI 0.42-1.38), and radiologically confirmed pneumonia (0.66, 95% CI 0.32-1.38) but inconsistent trends in outcomes associated with influenza.

Conclusions

No significant reductions were observed in any outcomes associated with RSV and influenza after PCV introduction.

The full value of immunisation against respiratory syncytial virus for infants younger than 1 year: effects beyond prevention of acute respiratory illness

Respiratory syncytial virus (RSV) is a leading cause of severe respiratory illness and death among children worldwide, particularly in children younger than 6 months and in low-income and middle-income countries. Feasible and cost-effective interventions to prevent RSV disease are not yet widely available, although two new products aimed at preventing RSV disease-long-acting monoclonal antibodies and maternal vaccines-have been licensed within the past 2 years. The primary target of these products is reduction of the substantial burden of RSV-associated acute lower respiratory tract infections (LRTI) in infants younger than 1 year. However, other important public health benefits might also accrue with the prevention of RSV-associated LRTI during the first year of life. Mounting evidence shows that preventing RSV-associated LRTI in infants younger than 1 year could prevent secondary pneumonia caused by other pathogens, reduce recurrent hospitalisations due to other respiratory diseases in later childhood, decrease all-cause infant mortality, ameliorate the burden of respiratory diseases on health-care systems, reduce inappropriate antibiotic use, and possibly improve lung health beyond infancy. We herein review current evidence and suggest approaches to better assess the magnitude of these potential secondary effects of RSV prevention, which, if proven substantial, are likely to be relevant to policy makers in many countries as they consider the use of these new products.

Prior pneumococcal vaccination improves in-hospital mortality among elderly population hospitalized due to community-acquired pneumonia

BACKGROUND

Pneumococcal vaccination is a preventive method to reduce pneumonia related mortality. However, real-world data on efficacy of the pneumococcal vaccine in reducing mortality is lacking, especially in elderly patients. This study was conducted to assess the effects of prior pneumococcal vaccination in elderly pneumonia patients.

METHODS

The data was procured from the Health Insurance Review and Assessment and Quality Assessment database. Hospitalized patients who met the criteria of community-acquired pneumonia (CAP) were included and they were grouped according to vaccination state. Patients were aged ≥ 65 years and treated with beta-lactam, quinolone, or macrolide. Patients were excluded when treatment outcomes were unknown.

RESULTS

A total of 4515 patients were evaluated, and 1609 (35.6%) of them were vaccinated prior to hospitalization. Mean age was 77.0 [71.0;82.0], 54.2% of them were male, and mean Charlson comorbidity index (CCI) was 3.0. The patients in the vaccinated group were younger than those in the unvaccinated group (76.0 vs. 78.0 years; P < 0.001), and showed higher in-hospital improvement (97.6 vs. 95.0%; P < 0.001) and lower 30-day mortality (2.6 vs. 5.3%; P < 0.001). After adjusting confounding factors such as age, gender, CURB score and CCI score, the vaccinated group demonstrated a significant reduction in 30-day mortality (hazard ratio [HR] 0.58, 95% confidence interval [CI] 0.41-0.81; P < 0.01) and in-hospital mortality (HR 0.53, 95% CI0.37-0.78; P < 0.001) compared to the unvaccinated group in multivariate analysis. Vaccinated group showed better 30-day survival than those in non-vaccinated group (log-rank test < 0.05).

CONCLUSIONS

Among elderly hospitalized CAP patients, prior pneumococcal vaccination was associated with improved in-hospital mortality and 30-day mortality.

Burden of respiratory syncytial virus disease across the lifespan in Australia and New Zealand: a scoping review

OBJECTIVES

Respiratory syncytial virus (RSV) is the leading cause of acute lower respiratory tract infection in young children worldwide. RSV is increasingly associated with severe respiratory disease in people aged >65 years. The heterogeneous landscape of RSV in Australia and New Zealand makes generalisation of results from global studies to local contexts difficult. Given the changing landscape of RSV, we aimed to examine the existing literature on the burden of RSV disease and identify evidence gaps in Australia and New Zealand.

STUDY DESIGN

Scoping review.

METHODS

We designed a scoping review protocol and searched the Web of Science and Scopus databases for eligible peer-reviewed publications. Data from eligible studies were charted and summarised in tabular and narrative form.

RESULTS

Of the 153 eligible publications identified, 123 investigated RSV disease in a hospital setting and six in primary care. Only six studies reported the economic burden of disease, all of which estimated direct healthcare costs associated with treatment and/or hospitalisation; no studies quantified the indirect costs or costs to families.

CONCLUSIONS

In this scoping review, we describe the effect of RSV disease in several high-risk populations, including children and adults. An improved understanding of the RSV burden of disease, both in primary care settings and economically, within the local context will assist with the implementation of preventative strategies, including vaccination programmes. Future studies to determine the true burden of RSV-associated morbidity, mortality and economic burden across the entire patient journey and among different healthcare settings will help prioritise emerging RSV therapeutics.

Respiratory syncytial virus disease morbidity in Australian infants aged 0 to 6 months: a systematic review with narrative synthesis

BACKGROUND

A significant proportion of the global respiratory syncytial virus (RSV) associated morbidity is accounted for by infants aged 0 to 6 months, who are particularly vulnerable to severe disease. In 2015, 44% of global hospitalisations in infants in this age group were secondary to RSV. The objective of this systematic review is to appraise and synthesise the local evidence of RSV infection morbidity among Australian infants aged 0 to 6 months and to assess the implications for future immunisation strategies.

METHODS

Electronic databases (Medline, Embase, Pubmed and Global Health) were searched for full-text articles published between 2000 and 2023 in English language. Studies that examined markers of RSV disease morbidity in infants aged 0 to 6 months in Australia who had laboratory confirmed RSV infection were eligible for inclusion. The outcomes of interest were incidence, prevalence, testing rate, positivity rate, mortality, emergency department visits, community health visits, hospitalisation, intensive care unit admission, supplementary oxygen use, mechanical ventilation, risk factors for disease severity and monoclonal antibody use.

RESULTS

The database search identified 469 studies. After removal of duplicates and full-text review, 17 articles were eligible for inclusion. This review was reported according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses and Synthesis without meta-analysis guidelines.

CONCLUSIONS

Qualitative analysis of the included studies showed that Australian infants aged 0 to 6 months have higher rates of RSV testing, positivity and incidence; and more likely to develop severe disease that requires hospitalisation, intensive care unit admission or respiratory support, compared to children and adults of all ages. Aboriginal and Torres Strait Islander infants aged 0 to 6 months demonstrated higher rates of RSV infection and hospitalisation, compared to non-Indigenous infants. Age-related trends persisted in geographic areas with varying seasonal transmission of RSV, and during the SARS-CoV-2 pandemic. Passive immunisation strategies targeting infants in their first 6 months of life, either via vaccination of pregnant women or administration of long-acting monoclonal antibody during infancy, could effectively reduce RSV disease burden in Australia.

Seasonality and risk factor analysis of respiratory syncytial virus infection in children in Taiwan-A retrospective study from 1995 to 2005

Respiratory syncytial virus (RSV) is one of the important pathogens leading to acute respiratory tract infection in infants and young children. We aimed to investigate the seasonality of RSV infection in different parts of Taiwan and to delineate the risk factors for severe RSV infections. We collected RSV-infected patients' data by retrospective chart review. A total of 1740 RSV-infected children aged under 18 years were enrolled. The infection was acquired during hospitalization in 103 (7.1%) children, while none of them required ventilator support or needed intensive care before RSV infection. The need for intensive care or ventilator support was significantly associated with congenital heart disease (CHD), chronic lung disease, and neuromuscular diseases. Age <1 year and nosocomially acquired infection are also significant predictors for the need of intensive care. Only the presence of CHD, especially acyanotic CHD, was significantly associated with a fatal outcome. RSV infection occurs all year round. Monthly distribution of RSV infections in Northern Taiwan showed a bimodal pattern, with one peak from March to May, and another from August to October. The distribution in Southern Taiwan showed a single peak from April to July. The occurrence of RSV correlates positively with temperature and rain. The bimodal seasonal distribution pattern in Northern Taiwan may be a transitional pattern shifting from a single high winter peak in temperate areas to a wider summer peak in tropical areas. Continuous surveillance is needed to explore the possible effect of global warming on the seasonality of RSV infection.

Incremental effectiveness of 23-valent pneumococcal polysaccharide vaccine against pneumonia hospitalisation among Australian Indigenous children: A record linkage study

BACKGROUND

The impact of pneumococcal conjugate vaccines (PCVs) on pneumonia in children is well-documented but data on 23-valent pneumococcal polysaccharide vaccine (PPV23) are lacking. Between 2001 and 2011, Indigenous children in Western Australia (WA) were recommended to receive PPV23 at 18-24 months of age following 3 doses of 7-valent PCV. We evaluated the incremental effectiveness of PPV23 against pneumonia hospitalisation.

METHODS

Indigenous children born in WA between 2001 and 2012 who received PCV dose 3 by 12 months of age were followed from 18 to 60 months of age for the first episode of pneumonia hospitalisation (all-cause and 3 subgroups: presumptive pneumococcal, other specified causes, and unspecified). We used Cox regression modelling to estimate hazard ratios (HRs) for pneumonia hospitalisation among children who had, versus had not, received PPV23 between 18 and 30 months of age after adjustment for confounders.

RESULTS

11,120 children had 327 first episodes of all-cause pneumonia hospitalisation, with 15 (4.6%) coded as presumptive pneumococcal, 46 (14.1%) as other specified causes and 266 (81.3%) unspecified. No statistically significant reduction in all-cause pneumonia was seen with PPV23 (HR 1.11; 95% CI: 0.87-1.43), but the direction of the association differed for presumptive pneumococcal (HR 0.47; 95% CI: 0.16-1.35) and specified (HR 0.89; 95% CI: 0.49-1.62) from unspecified causes (HR 1.13; 95% CI: 0.86-1.49). During the baseline period before PPV23 vaccination (12-18 months), all-cause pneumonia risk was higher among PPV23-vaccinated than unvaccinated children (RR: 1.73; 95% CI: 1.30-2.28).

CONCLUSION

In this high-risk population, no statistically significant incremental effect of a PPV23 booster at 18-30 months was observed against hospitalised all-cause pneumonia or the more specific outcome of presumptive pneumococcal pneumonia. Confounding by indication may explain the slight trend towards an increased risk against all-cause pneumonia. Larger studies with better control of confounding are needed to further inform PPV23 vaccination.

Vaccine coverage and effectiveness against laboratory-confirmed symptomatic and severe Covid-19 in indigenous people in Brazil: a cohort study

BACKGROUND

Indigenous people have historically suffered devastating impacts from epidemics and continue to have lower access to healthcare and be especially vulnerable to respiratory infections. We estimated the coverage and effectiveness of Covid-19 vaccines against laboratory-confirmed Covid-19 cases among indigenous people in Brazil.

METHODS

We linked nationwide Covid-19 vaccination data with flu-like surveillance records and studied a cohort of vaccinated indigenous people aged ≥ 5 years between 18th January 2021 and 1st March 2022. We considered individuals unexposed from the date they received the first dose of vaccine until the 13th day of vaccination, partially vaccinated from the 14th day after the first dose until the 13th day after receiving the second dose, and fully vaccinated onwards. We estimated the Covid-19 vaccination coverage and used Poisson regression to calculate the relative risks (RR) and vaccine effectiveness (VE) of CoronaVac, ChAdOx1, and BNT162b2 against Covid-19 laboratory-confirmed cases incidence, mortality, hospitalisation, and hospital-progression to Intensive Care Unit (ICU) or death. VE was estimated as (1-RR)*100, comparing unexposed to partially or fully vaccinated.

RESULTS

By 1st March 2022, 48.7% (35.0-62.3) of eligible indigenous people vs. 74.8% (57.9-91.8) overall Brazilians had been fully vaccinated for Covid-19. Among fully vaccinated indigenous people, we found a lower risk of symptomatic cases (RR: 0.47, 95%CI: 0.40-0.56) and mortality (RR: 0.47, 95%CI: 0.14-1.56) after the 14th day of the second dose. VE for the three Covid-19 vaccines combined was 53% (95%CI:44-60%) for symptomatic cases, 53% (95%CI:-56-86%) for mortality and 41% (95%CI:-35-75%) for hospitalisation. In our sample, we found that vaccination did not reduce Covid-19 related hospitalisation. However, among hospitalised patients, we found a lower risk of progression to ICU (RR: 0.14, 95%CI: 0.02-0.81; VE: 87%, 95%CI:27-98%) and Covid-19 death (RR: 0.04, 95%CI:0.01-0.10; VE: 96%, 95%CI: 90-99%) after the 14th day of the second dose.

CONCLUSIONS

Lower coverage but similar Covid-19 VE among indigenous people than overall Brazilians suggest the need to expand access, timely vaccination, and urgently offer booster doses to achieve a great level of protection among this group.

Influenza-associated hospitalisation and mortality rates among global Indigenous populations; a systematic review and meta-analysis

BACKGROUND

More than 50 million influenza infections and over 100,000 deaths from influenza occur annually. While Indigenous populations experience an inequitable influenza burden, the magnitude of this inequity has not previously been estimated on a global scale. This study compared rates of influenza-associated hospitalisation and mortality between Indigenous and non-Indigenous populations globally.

METHODS

A systematic review and meta-analysis was conducted including literature published prior to 13 July 2021. Eligible articles either reported a rate ratio (RR) comparing laboratory-confirmed influenza-associated hospitalisation and/or mortality between an Indigenous population and a corresponding benchmark population, or reported sufficient information for this to be calculated using publicly available data. Findings were reported by country/region and pooled by country and period (pandemic/seasonal) when multiple studies were available using a random-effects model. The I2 statistic assessed variability between studies.

RESULTS

Thirty-six studies (moderate/high quality) were included; all from high or high-middle income countries. The pooled influenza-associated hospitalisation RR (HRR) for indigenous compared to benchmark populations was 5·7 (95% CI: 2·7-12·0) for Canada, 5·2 (2.9-9.3) for New Zealand, and 5.2 (4.2-6.4) for Australia. Of the Australian studies, the pooled HRR for seasonal influenza was 3.1 (2·7-3·5) and for pandemic influenza was 6·2 (5·1-7·5). Heterogeneity was slightly higher among studies of pandemic influenza than seasonal influenza. The pooled mortality RR was 4.1 (3·0-5.7) in Australia and 3·3 (2.7-4.1) in the United States.

CONCLUSIONS

Ethnic inequities in severe influenza persist and must be addressed by reducing disparities in the underlying determinants of health. Influenza surveillance systems worldwide should include Indigenous status to determine the extent of the disease burden among Indigenous populations. Ethnic inequities in pandemic influenza illustrate the need to prioritise Indigenous populations in pandemic response plans.

RSV through the COVID-19 pandemic: Burden, shifting epidemiology, and implications for the future

Respiratory syncytial virus (RSV) represents a major global healthcare burden, particularly in those under 5 years of age. There is no available vaccine, with treatment limited to supportive care or palivizumab for high-risk children. Additionally, although a causal relationship has not been established, RSV has been associated with the development of asthma or wheezing in some children. The COVID-19 pandemic and the introduction of nonpharmaceutical interventions (NPIs) have caused substantial changes to RSV seasonality and epidemiology. Many countries have experienced an absence of RSV during the time of a typical season, followed by an out-of-season surge upon relaxation of NPI use. These dynamics have disrupted traditional RSV disease patterns and assumptions, but also provide a unique opportunity to learn more about the transmission of RSV and other respiratory viruses, as well as inform future approaches to RSV preventive strategies. Here, we review the RSV burden and epidemiology through the COVID-19 pandemic and discuss how new data may affect future decisions regarding RSV prevention.

Clinical and economic burden of respiratory syncytial virus in Spanish children: the BARI study

Respiratory syncytial virus (RSV) infection is a major cause of morbidity in children. However, its disease burden remains poorly understood, particularly outside of the hospital setting. Our study aimed to estimate the burden of medically attended acute lower respiratory infection (ALRI) cases potentially related to RSV in Spanish children. Longitudinal data from September 2017 to June 2018 of 51,292 children aged < 5 years old from the National Healthcare System (NHS) of two Spanish regions were used. Three case definitions were considered: (a) RSV-specific; (b) RSV-specific and unspecified acute bronchiolitis (RSV-specific and Bronchiolitis), and; (c) RSV-specific and unspecified ALRI (RSV-specific and ALRI). A total of 3460 medically attended ALRI cases potentially due to RSV were identified, of which 257 (7.4%), 164 (4.7%), and 3039 (87.8%) coded with RSV-specific, unspecific bronchiolitis, and unspecific ALRI codes, respectively. Medically attended RSV-specific and ALRI cases per 1000 children was 134.4 in the first year of life, 119.4 in the second, and 35.3 between 2 and 5 years old. Most cases were observed in otherwise healthy children (93.1%). Mean direct healthcare cost per medically attended RSV-specific and ALRI case was €1753 in the first year of life, €896 in the second, and €683 between 2 and 5 years old. Hospitalization was the main driver of these costs, accounting for 55.6%, 38.0% and 33.4%, in each respective age group. In RSV-specific cases, mean direct healthcare cost per medically attended case was higher, mostly due to hospitalization: €3362 in the first year of life (72.9% from hospitalizations), €3252 in the second (72.1%), and €3514 between 2 and 5 years old (74.2%). These findings suggest that hospitalization data alone will underestimate the RSV infections requiring medical care, as will relying only on RSV-specific codes. RSV testing and codification must be improved and preventive solutions adopted, to protect all infants, particularly during the first year of life.

Childhood pneumonia in New Zealand

While deaths from pneumonia during childhood in New Zealand (NZ) are now infrequent, childhood pneumonia remains a significant cause of morbidity. In this viewpoint, we describe pneumonia epidemiology in NZ and identify modifiable risk factors. During recent decades, pneumonia hospitalisation rates decreased, attributable in part to inclusion of pneumococcal conjugate vaccine in NZ's immunisation schedule. Irrespective of these decreases, pneumonia hospitalisation rates are four times higher for Pacific and 60% higher for Māori compared with children of other ethnic groups. Consistent with other developed countries, hospitalisation rates for pneumonia with pleural empyema increased in NZ during the 2000s. Numerous factors contribute to childhood pneumonia acquisition, hospitalisation and morbidity in NZ include poor quality living environments, malnutrition during pregnancy and early childhood, incomplete and delayed vaccination during pregnancy and childhood and variable primary and secondary care management. To reduce childhood pneumonia disease burden, interventions should focus on addressing modifiable risk factors for pneumonia. These include using non-polluting forms of household heating; decreasing cigarette smoke exposure; reducing household acute respiratory infection transmission; improving dietary nutritional content and nutrition during pregnancy and early childhood; breastfeeding promotion; vaccination during pregnancy and childhood and improving the quality of and decreasing the variance in primary and secondary care management of pneumonia.

Synergism and Antagonism of Bacterial-Viral Coinfection in the Upper Respiratory Tract

Streptococcus pneumoniae (the pneumococcus) is a leading cause of pneumonia in children under 5 years of age. Coinfection by pneumococci and respiratory viruses enhances disease severity. Little is known about pneumococcal coinfections with respiratory syncytial virus (RSV). Here, we developed a novel infant mouse model of coinfection using pneumonia virus of mice (PVM), a murine analogue of RSV, to examine the dynamics of coinfection in the upper respiratory tract, an anatomical niche that is essential for host-to-host transmission and progression to disease. Coinfection increased damage to the nasal tissue and increased production of the chemokine CCL3. Nasopharyngeal pneumococcal density and shedding in nasal secretions were increased by coinfection. In contrast, coinfection reduced PVM loads in the nasopharynx, an effect that was independent of pneumococcal strain and the order of infection. We showed that this "antagonistic" effect was absent using either ethanol-killed pneumococci or a pneumococcal mutant deficient in capsule production and incapable of nasopharyngeal carriage. Colonization with a pneumococcal strain naturally unable to produce capsule also reduced viral loads. The pneumococcus-mediated reduction in PVM loads was caused by accelerated viral clearance from the nasopharynx. Although these synergistic and antagonistic effects occurred with both wild-type pneumococcal strains used in this study, the magnitude of the effects was strain dependent. Lastly, we showed that pneumococci can also antagonize influenza virus. Taken together, our study has uncovered multiple novel facets of bacterial-viral coinfection. Our findings have important public health implications, including for bacterial and viral vaccination strategies in young children. IMPORTANCE Respiratory bacterial-viral coinfections (such as pneumococci and influenza virus) are often synergistic, resulting in enhanced disease severity. Although colonization of the nasopharynx is the precursor to disease and transmission, little is known about bacterial-viral interactions that occur within this niche. In this study, we developed a novel mouse model to examine pneumococcal-viral interactions in the nasopharynx with pneumonia virus of mice (PVM) and influenza. We found that PVM infection benefits pneumococci by increasing their numbers in the nasopharynx and shedding of these bacteria in respiratory secretions. In contrast, we discovered that pneumococci decrease PVM numbers by accelerating viral clearance. We also report a similar effect of pneumococci on influenza. By showing that coinfections lead to both synergistic and antagonistic outcomes, our findings challenge the existing dogma in the field. Our work has important applications and implications for bacterial and viral vaccines that target these microbes.

Novel Biomarkers Differentiating Viral from Bacterial Infection in Febrile Children: Future Perspectives for Management in Clinical Praxis

Differentiating viral from bacterial infections in febrile children is challenging and often leads to an unnecessary use of antibiotics. There is a great need for more accurate diagnostic tools. New molecular methods have improved the particular diagnostics of viral respiratory tract infections, but defining etiology can still be challenging, as certain viruses are frequently detected in asymptomatic children. For the detection of bacterial infections, time consuming cultures with limited sensitivity are still the gold standard. As a response to infection, the immune system elicits a cascade of events, which aims to eliminate the invading pathogen. Recent studies have focused on these host–pathogen interactions to identify pathogen-specific biomarkers (gene expression profiles), or “pathogen signatures”, as potential future diagnostic tools. Other studies have assessed combinations of traditional bacterial and viral biomarkers (C-reactive protein, interleukins, myxovirus resistance protein A, procalcitonin, tumor necrosis factor-related apoptosis-inducing ligand) to establish etiology. In this review we discuss the performance of such novel diagnostics and their potential role in clinical praxis. In conclusion, there are several promising novel biomarkers in the pipeline, but well-designed randomized controlled trials are needed to evaluate the safety of using these novel biomarkers to guide clinical decisions.

Evaluation of the impact of childhood 13-valent pneumococcal conjugate vaccine introduction on adult pneumonia in Ulaanbaatar, Mongolia: study protocol for an observational study

BACKGROUND

Community-acquired pneumonia is an important cause of morbidity and mortality in adults. Approximately one-third of pneumonia cases can be attributed to the pneumococcus. Pneumococcal conjugate vaccines (PCVs) protect against colonisation with vaccine-type serotypes. The resulting decrease in transmission of vaccine serotypes leads to large indirect effects. There are limited data from developing countries demonstrating the impact of childhood PCV immunisation on adult pneumonia. There are also insufficient data available on the burden and severity of all-cause pneumonia and respiratory syncytial virus (RSV) in adults from low resource countries. There is currently no recommendation for adult pneumococcal vaccination with either pneumococcal polysaccharide vaccine or PCVs in Mongolia. We describe the protocol developed to evaluate the association between childhood 13-valent PCV (PCV13) vaccination and trends in adult pneumonia.

METHODS

PCV13 was introduced into the routine childhood immunisation schedule in Mongolia in a phased manner from 2016. In March 2019 we initiated active hospital-based surveillance for adult pneumonia, with the primary objective of evaluating trends in severe hospitalised clinical pneumonia incidence in adults 18 years and older in four districts of Ulaanbaatar. Secondary objectives include measuring the association between PCV13 introduction and trends in all clinically-defined pneumonia, radiologically-confirmed pneumonia, nasopharyngeal carriage of S. pneumoniae and pneumonia associated with RSV or influenza. Clinical questionnaires, nasopharyngeal swabs, urine samples and chest radiographs were collected from enrolled patients. Retrospective administrative and clinical data were collected for all respiratory disease-related admissions from January 2015 to February 2019.

DISCUSSION

Establishing a robust adult surveillance system may be an important component of monitoring the indirect impact of PCVs within a country. Monitoring indirect impact of childhood PCV13 vaccination on adult pneumonia provides additional data on the full public health impact of the vaccine, which has implications for vaccine efficiency and cost-effectiveness. Adult surveillance in Mongolia will contribute to the limited evidence available on the burden of pneumococcal pneumonia among adults in low- and middle-income countries, particularly in the Asia-Pacific region. In addition, it is one of the few examples of implementing prospective, population-based pneumonia surveillance to evaluate the indirect impact of PCVs in a resource-limited setting.

Australia's Role in Pneumococcal and Human Papillomavirus Vaccine Evaluation in Asia-Pacific

Australian researchers have made substantial contributions to the field of vaccinology over many decades. Two examples of this contribution relate to pneumococcal vaccines and the human papillomavirus (HPV) vaccine, with a focus on improving access to these vaccines in low- and lower-middle-income countries (LLMICs). Many LLMICs considering introducing one or both of these vaccines into their National Immunisation Programs face significant barriers such as cost, logistics associated with vaccine delivery. These countries also often lack the resources and expertise to undertake the necessary studies to evaluate vaccine performance. This review summarizes the role of Australia in the development and/or evaluation of pneumococcal vaccines and the HPV vaccine, including the use of alternative vaccine strategies among countries situated in the Asia-Pacific region. The outcomes of these research programs have had significant global health impacts, highlighting the importance of these vaccines in preventing pneumococcal disease as well as HPV-associated diseases.

Levels of pneumococcal conjugate vaccine coverage and indirect protection against invasive pneumococcal disease and pneumonia hospitalisations in Australia: An observational study

BACKGROUND

There is limited empiric evidence on the coverage of pneumococcal conjugate vaccines (PCVs) required to generate substantial indirect protection. We investigate the association between population PCV coverage and indirect protection against invasive pneumococcal disease (IPD) and pneumonia hospitalisations among undervaccinated Australian children.

METHODS AND FINDINGS

Birth and vaccination records, IPD notifications, and hospitalisations were individually linked for children aged <5 years, born between 2001 and 2012 in 2 Australian states (New South Wales and Western Australia; 1.37 million children). Using Poisson regression models, we examined the association between PCV coverage, in small geographical units, and the incidence of (1) 7-valent PCV (PCV7)-type IPD; (2) all-cause pneumonia; and (3) pneumococcal and lobar pneumonia hospitalisation in undervaccinated children. Undervaccinated children received <2 doses of PCV at <12 months of age and no doses at ≥12 months of age. Potential confounding variables were selected for adjustment a priori with the assistance of a directed acyclic graph. There were strong inverse associations between PCV coverage and the incidence of PCV7-type IPD (adjusted incidence rate ratio [aIRR] 0.967, 95% confidence interval [CI] 0.958 to 0.975, p-value < 0.001), and pneumonia hospitalisations (all-cause pneumonia: aIRR 0.991 95% CI 0.990 to 0.994, p-value < 0.001) among undervaccinated children. Subgroup analyses for children <4 months old, urban, rural, and Indigenous populations showed similar trends, although effects were smaller for rural and Indigenous populations. Approximately 50% coverage of PCV7 among children <5 years of age was estimated to prevent up to 72.5% (95% CI 51.6 to 84.4) of PCV7-type IPD among undervaccinated children, while 90% coverage was estimated to prevent 95.2% (95% CI 89.4 to 97.8). The main limitations of this study include the potential for differential loss to follow-up, geographical misclassification of children (based on residential address at birth only), and unmeasured confounders.

CONCLUSIONS

In this study, we observed substantial indirect protection at lower levels of PCV coverage than previously described-challenging assumptions that high levels of PCV coverage (i.e., greater than 90%) are required. Understanding the association between PCV coverage and indirect protection is a priority since the control of vaccine-type pneumococcal disease is a prerequisite for reducing the number of PCV doses (from 3 to 2). Reduced dose schedules have the potential to substantially reduce program costs while maintaining vaccine impact.

Etiology of Clinical Community-Acquired Pneumonia in Swedish Children Aged 1-59 Months with High Pneumococcal Vaccine Coverage-The TREND Study

(1) Immunization with pneumococcal conjugate vaccines has decreased the burden of community-acquired pneumonia (CAP) in children and likely led to a shift in CAP etiology. (2) The Trial of Respiratory infections in children for ENhanced Diagnostics (TREND) enrolled children 1-59 months with clinical CAP according to the World Health Organization (WHO) criteria at Sachs' Children and Youth Hospital, Stockholm, Sweden. Children with rhonchi and indrawing underwent "bronchodilator challenge". C-reactive protein and nasopharyngeal PCR detecting 20 respiratory pathogens, were collected from all children. Etiology was defined according to an a priori defined algorithm based on microbiological, biochemical, and radiological findings. (3) Of 327 enrolled children, 107 (32%) required hospitalization; 91 (28%) received antibiotic treatment; 77 (24%) had a chest X-ray performed; and 60 (18%) responded to bronchodilator challenge. 243 (74%) episodes were classified as viral, 11 (3%) as mixed viral-bacterial, five (2%) as bacterial, two (0.6%) as atypical bacterial and 66 (20%) as undetermined etiology. After exclusion of children responding to bronchodilator challenge, the proportion of bacterial and mixed viral-bacterial etiology was 1% and 4%, respectively. (4) The novel TREND etiology algorithm classified the majority of clinical CAP episodes as of viral etiology, whereas bacterial etiology was uncommon. Defining CAP in children <5 years is challenging, and the WHO definition of clinical CAP is not suitable for use in children immunized with pneumococcal conjugate vaccines.

Use of Chest Radiography Examination as a Probe for Pneumococcal Conjugate Vaccine Impact on Lower Respiratory Tract Infections in Young Children

BACKGROUND

Community-acquired alveolar pneumonia (CAAP) is considered a bacterial disease, mainly pneumococcal. CAAP rates markedly declined following 7- and 13-valent pneumococcal conjugate vaccine (PCV) introductions worldwide. In contrast, non-CAAP lower respiratory tract infections (NA-LRIs) are generally not considered pneumococcal diseases. We assessed CAAP, NA-LRIs, and overall visits with chest radiograph (CXR) examination rates in the pediatric emergency room in southern Israel before and after PCV implementation.

METHODS

This was an ongoing, prospective observational study. Our hospital serves a captive population of approximately 75 000 children aged <5 years, enabling incidence calculation. PCV7 and PCV13 were implemented in Israel in July 2009 and November 2010, respectively. All CXRs were analyzed according to the World Health Organization Standardization of Interpretation. We calculated CAAP, NA-LRI, and CXR examinations annual incidences from 2004 to 2017 and incidence rate ratios comparing the PCV13 (2014-2017) with the pre-PCV (2004-2008) periods.

RESULTS

Overall, 72 746 CXR examinations were recorded: 14% CAAP and 86% NA-LRI. CAAP, NA-LRI, and CXR examination visit rates declined by 49%, 34%, and 37%, respectively. This pattern was seen in Jewish and Bedouin children (the 2 ethnically distinct populations), with steeper declines observed among Jewish children and children aged >12 months.

CONCLUSIONS

PCV7/PCV13 implementation resulted in a marked decline in CAAP and overall visits with CXR examination rates in young children. Overall, approximately 14 750 hospital visits with CXR were prevented annually per 100 000 population aged <5 years. These findings suggest that although NA-LRIs are usually not considered pneumococcal, many can be prevented by PCVs.Pneumococcal conjugate vaccine (PCV7/PCV13) implementation resulted in significant declines in community-acquired alveolar pneumonia (CAAP) and overall chest radiography examination rates in young children. Although non-CAAP lower respiratory tract infections are usually not considered pneumococcal, many can be prevented by PCVs.

Assessing the Burden of Laboratory-Confirmed Respiratory Syncytial Virus Infection in a Population Cohort of Australian Children Through Record Linkage

BACKGROUND

Significant progress has been made towards an effective respiratory syncytial virus (RSV) vaccine. Age-stratified estimates of RSV burden are urgently needed for vaccine implementation. Current estimates are limited to small cohorts or clinical coding data only. We present estimates of laboratory-confirmed RSV across multiple severity levels.

METHODS

We linked laboratory, perinatal, and hospital data of 469 589 children born in Western Australia in 1996-2012. Respiratory syncytial virus tests and detections were classified into community, emergency department (ED), and hospital levels to estimate infection rates. Clinical diagnoses given to children with RSV infection presenting to ED or hospitalized were identified.

RESULTS

In 2000-2012, 10% (n = 45 699) of children were tested for RSV and 16% (n = 11 461) of these tested positive. Respiratory syncytial virus was detected in community, ED (both 0.3 per 1000 child-years), and hospital (2.4 per 1000 child-years) settings. Respiratory syncytial virus-confirmed rates were highest among children aged <3 months (31 per 1000 child-years). At least one third of children with RSV infection presenting to ED were diagnosed as other infection, other respiratory, or other (eg, agranulocytosis).

CONCLUSIONS

Respiratory syncytial virus is pervasive across multiple severity levels and diagnoses. Vaccines targeting children <3 months must be prioritized. Given that most children are never tested, estimating the under-ascertainment of RSV infection is imperative.

Modern approaches to pharmacotherapy of Community-Acquired Pneumonia

Introduction: The study presents current views on the pharmacotherapy of community-acquired pneumonia (CAP). This study also describes in general terms the current pharmacoepidemiological situation of the CAP in Russia and abroad, which can both help medical professionals make an informed choice when choosing a pharmacotherapy, and inspire them to follow-up research and observations.

The aim of the study is to conduct an analysis of the available research on the pharmacotherapy of CAP in order to accelerate the accumulation and assimilation of knowledge in the field of this pathology.

Materials and methods: The following databases of medical publications and electronic libraries were used to search for the relevant sources of information: PubMed, Medline, Google Scholar, Crossref, and eLIBRARY.RU.

Results and discussion: The choice of a rational antimicrobial therapy (AMT) for CAP is of high relevance due to the widespread of the pathology. The article highlights modern approaches to the pharmacotherapy of CAP in adults, including a review of promising new drugs, and presents the main problematic issues related to the emergence of antibiotic resistance of pathogens, as well as methods to combat it.

Conclusion: The analyzed and generalized results of the conducted research allow the authors to make a conclusion about the feasibility of a more detailed study and raising the level of awareness of medical professionals in this pathology.

SARS-CoV2 coronavirus: so far polite with children. Debatable immunological and non-immunological evidence

The reasons for the relative resistance of children to certain infections such as that caused by coronavirus SARS-CoV2 are not yet fully clear. Deciphering these differences can provide important information about the pathogenesis of the disease. Regarding the SARS-CoV2 virus, children are at the same risk of infection as the general population of all ages, with the most serious cases being found in infants. However, it has been reported that the disease is much less frequent than in adults and that most cases are benign or moderate (even with high viral loads), provided there are no other risk factors or underlying diseases. It is not clear why they have lower morbidity and virtually no mortality. A series of findings, relationships and behavioral patterns between the infectious agent and the child host may account for the lower incidence and a greatly attenuated clinical presentation of the disease in children.

Unique Features of Hospitalized Children with Alveolar Pneumonia Suggest Frequent Viral-Bacterial Coinfections

BACKGROUND

The World Health Organization Pneumonia Expert Group (WHO-PEG) defined a standardized radiologic endpoint for childhood community-acquired alveolar pneumonia (RD-CAAP), as the most likely to be pneumococcal, not ruling out other bacteria or coinfecting viruses. We aimed to determine the characteristics associated with hospitalization among children <5 years old presenting to the pediatric emergency room (PER) with RD-CAAP.

METHODS

This study was a part of an ongoing prospective population-based surveillance on hospital visits for RD-CAAP. RD-CAAP was determined according to the WHO-PEG. The study was conducted in the prepneumococcal conjugate vaccine era (2004-2008).

RESULTS

Of 24,432 episodes with chest radiographs, 3871)15.8%) were RD-CAAP: 2319 required hospitalization and 1552 were discharged (outpatients). Compared with outpatients, hospitalized children had lower temperature, peripheral white cell and absolute neutrophil counts and C reactive protein serum levels, but higher rates of hypoxemia, rhinorrhea, cough and respiratory virus detection. PER visits during the respiratory virus season presented a 1.83 times higher risk of hospitalization than visits during nonrespiratory season.

CONCLUSIONS

Although RD-CAAP is most often a bacterial infection, the unique characteristics of those visiting the PER and subsequently hospitalized suggest a frequent involvement of respiratory viruses, potentially as viral-bacterial coinfections, compared with outpatients.

Pneumococcal conjugate vaccine modulates macrophage-mediated innate immunity in pneumonia caused by Streptococcus pneumoniae following influenza

Pneumococcal conjugate vaccination (PCV) may prevent influenza-related pneumonia, including Streptococcus pneumoniae pneumonia. To investigate PCV efficacy against secondary pneumococcal pneumonia following influenza, PCV was administered intramuscularly 2 and 5 weeks before S. pneumoniae serotype-3 colonization of murine nasopharynges followed by intranasal challenge with a sublethal dose of influenza A virus. Bacterial and viral loads, including innate immune responses were compared across conditions. PCV vaccination improved the survival of mice with secondary pneumococcal pneumonia and significantly reduced the pulmonary bacterial burden. Increased monocyte/macrophage influx into the lungs, alleviated loss of alveolar macrophages and decreased neutrophil influx into the lungs occurred in PCV-treated mice irrespective of pneumococcal colonization. Higher monocyte chemoattractant protein 1 levels and lower levels of CXCL1, interferon-γ, interleukin-17A, and IL-10, were detected in PCV-treated mice. Additionally, PCV treatment activated the macrophage intracellular killing of S. pneumoniae. Collectively, PCV potentially modulates the host's innate immunity and specific antibodies induction. Macrophage-related innate immunity should be further explored to elucidate the efficacy and mechanisms of PCV versus influenza-related life-threatening diseases.

Characteristics of Hospitalized Rhinovirus-Associated Community-Acquired Pneumonia in Children, Finland, 2003-2014

Background: Rhinovirus (RV) is the most common cause of respiratory tract infections in children but, still, the clinical characteristics of RV-associated pneumonia have not been sufficiently investigated.

Methods: We identified children and adolescents younger than 18 years of age treated for community-acquired pneumonia as inpatients at the Turku University Hospital from 2003 to 2014 and analyzed for RV by PCR of a respiratory tract specimen. We collected the data from medical records and compared RV-positive children with RV-negative children.

Results: Of the study population of 313 children with pneumonia who were studied for RV, it was detected in 82 (26%). RV-positive children were younger (median age 2.6 years, interquartile range [IQR] 1.1–4.6 vs. 3.5 years, IQR 1.7–8.3, p = 0.002) and they had more often a history of preterm birth (16% vs. 5%, adjusted odds ratio 2.89, 95% confidence interval 1.21–6.92, p = 0.017) than RV-negative children. RV-positive children had a higher median white blood cell count than RV-negative children at presentation with pneumonia. The signs, symptoms, and severity of pneumonia were mostly similar in RV-positive and RV-negative children.

Conclusions: RV was frequently detected in young children hospitalized with community-acquired pneumonia. We identified premature birth as a factor associated with RV-positive pneumonia. The clinical features of pneumonia did not clearly differ between RV-positive and RV-negative children. Further studies are needed to clarify the clinical significance of detection of RV in children with pneumonia.

Human metapneumovirus prevalence and patterns of subgroup persistence identified through surveillance of pediatric pneumonia hospital admissions in coastal Kenya, 2007-2016

BACKGROUND

Human metapneumovirus (HMPV) is an important respiratory pathogen that causes seasonal epidemics of acute respiratory illness and contributes significantly to childhood pneumonia. Current knowledge and understanding on its patterns of spread, prevalence and persistence in communities in low resource settings is limited.

METHODS

We present findings of a molecular-epidemiological analysis of nasal samples from children < 5 years of age admitted with syndromic pneumonia between 2007 and 2016 to Kilifi County Hospital, coastal Kenya. HMPV infection was detected using real-time RT-PCR and positives sequenced in the fusion (F) and attachment (G) genes followed by phylogenetic analysis. The association between disease severity and HMPV subgroup was assessed using Fisher's exact test.

RESULTS

Over 10 years, 274/6756 (4.1%) samples screened were HMPV positive. Annual prevalence fluctuated between years ranging 1.2 to 8.7% and lowest in the recent years (2014-2016). HMPV detections were most frequent between October of one year to April of the following year. Genotyping was successful for 205/274 (74.8%) positives revealing clades A2b (41.0%) and A2c (10.7%), and subgroups B1 (23.4%) and B2 (24.9%). The dominance patterns were: clade A2b between 2007 and 11, subgroup B1 between 2012 and 14, and clade A2c in more recent epidemics. Subgroup B2 viruses were present in all the years. Temporal phylogenetic clustering within the subgroups for both local and global sequence data was seen. Subgroups occurring in each epidemic season were comprised of multiple variants. Pneumonia severity did not vary by subgroup (p = 0.264). In both the F and G gene, the sequenced regions were found to be predominantly under purifying selection.

CONCLUSION

Subgroup patterns from this rural African setting temporally map with global strain distribution, suggesting a well-mixed global virus transmission pool of HMPV. Persistence in the local community is characterized by repeated introductions of HMPV variants from the global pool. The factors underlying the declining prevalence of HMPV in this population should be investigated.

Effectiveness of pneumococcal conjugate vaccine against hospital admissions for pneumonia in Australian children: a retrospective, population-based, record-linked cohort study

BACKGROUND

Reductions in pneumonia hospitalisations following introduction of pneumococcal conjugate vaccines (PCVs) have been reported from high-incidence and low-incidence settings but long-term data comparing vaccinated with unvaccinated children are sparse.

METHODS

We did a retrospective, population-based, record-linkage cohort study in Australian children using administrative health data from the Western Australian Midwives' Notification System and New South Wales Perinatal Data Collection, and the birth and death registries in both states. PCV vaccination details, pneumonia-coded hospital admissions, and invasive pneumococcal disease notification records were individually linked for children born between 2001 and 2012. The primary outcome was defined as the first hospital admission for all-cause pneumonia. Cox models were used to calculate adjusted hazard ratios (HR) to estimate the effect of PCV doses on pneumonia-coded hospital admissions by Aboriginal status, birth period, remoteness, and pneumonia diagnostic category in children younger than 2 years. Person-time of follow-up time for each child started at birth and was censored at the earliest of first hospital admission for all-cause pneumonia, death, invalid PCV dose, when the child reached age 24 months, or the end date of the study period (Dec 31, 2013) FINDINGS: The study cohort comprised 1 365 893 children liveborn between Jan 1, 2001, and Dec 31, 2012, of whom 66 484 (4·9%) were identified as Aboriginal. The overall rate for all-cause pneumonia hospital admissions for children younger than 2 years over the entire study period was 17·6/1000 child-years in Aboriginal children and 5·5/1000 child-years in non-Aboriginal children. Compared with children born between 2001 and 2004 (ie, the pre-universal PCV period), the incidence of pneumonia-coded hospital admissions decreased in both vaccinated (6·5 vs 5·7 per 1000 child-years [12% reduction, 95% CI 3-21; p=0·01]) and unvaccinated non-Aboriginal children (6·8 vs 3·7 [45% reduction; 41-49]) born 2005-12 (the universal PCV period); among Aboriginal children, declines were significant only among those vaccinated (27·4 vs 14·1 [49% reduction, 40-55]). Among Aboriginal children born 2005-12, the risk of pneumonia-coded hospital admission after three doses of PCV was lower than those unvaccinated (adjusted HR 0·83, 95% CI 0·65-0·99) but, among non-Aboriginal children, the risk was similar (adjusted HR 1·09, 0·98-1·22). Overall, remote-born Aboriginal children had the highest incidence of hospital admission for pneumonia and among children born 2005-12, the adjusted risk was 37% lower (adjusted HR 0·63, 95% CI 0·42-0·96) among those fully vaccinated than those unvaccinated.

INTERPRETATION

Reductions in pneumonia-coded hospital admissions in unvaccinated children predominated in non-Aboriginal children with low incidence of pneumonia but were not significant in Aboriginal children with high incidence. These findings have potential implications for measuring PCV effect using a non-specific endpoint such as all-cause pneumonia in high-incidence populations.

FUNDING

Commonwealth Government Collaborative Research Infrastructure Strategy and Education Investment Fund Super Science Initiative and the Australian National Health and Medical Research Council.

The contribution of viruses and bacteria to community-acquired pneumonia in vaccinated children: a casecontrol study

INTRODUCTION

Respiratory pathogens associated with childhood pneumonia are often detected in the upper respiratory tract of healthy children, making their contribution to pneumonia difficult to determine. We aimed to determine the contribution of common pathogens to pneumonia adjusting for rates of asymptomatic detection to inform future diagnosis, treatment and preventive strategies.

METHODS

A case-control study was conducted among children <18 years in Perth, Western Australia. Cases were children hospitalised with radiologically confirmed pneumonia; controls were healthy children identified from outpatient and local immunisation clinics. Nasopharyngeal swabs were collected and tested for 14 respiratory viruses and 6 bacterial species by Polymerase chain reaction (PCR). For each pathogen, adjusted odds ratio (aOR; 95% CI) was calculated using multivariate logistic regression and population-attributable fraction (95% CI) for pneumonia was estimated.

RESULTS

From May 2015 to October 2017, 230 cases and 230 controls were enrolled. At least one respiratory virus was identified in 57% of cases and 29% of controls (aOR: 4.7; 95% CI: 2.8 to 7.8). At least one bacterial species was detected in 72% of cases and 80% of controls (aOR: 0.7; 95% CI: 0.4 to 1.2). Respiratory syncytial virus (RSV) detection was most strongly associated with pneumonia (aOR: 58.4; 95% CI: 15.6 to 217.5). Mycoplasma pneumoniae was the only bacteria associated with pneumonia (aOR: 14.5; 95% CI: 2.2 to 94.8). We estimated that RSV, human metapneumovirus (HMPV), influenza, adenovirus and Mycoplasma pneumoniae were responsible for 20.2% (95% CI: 14.6 to 25.5), 9.8% (5.6% to 13.7%), 6.2% (2.5% to 9.7%), 4% (1.1% to 7.1%) and 7.2% (3.5% to 10.8%) of hospitalisations for childhood pneumonia, respectively.

CONCLUSIONS

Respiratory viruses, particularly RSV and HMPV, are major contributors to pneumonia in Australian children.

Use of data linkage to improve communicable disease surveillance and control in Australia: existing practices, barriers and enablers

OBJECTIVES

To review the use of data linkage by Australian state and territory communicable disease control units, and to identify barriers to and enablers of data linkage to inform communicable disease surveillance and control activities.

METHODS

Semi-structured telephone interviews were carried out with one key informant from communicable disease control units in all eight Australian states and territories between October 2017 and January 2018.

RESULTS

Key informants from all Australian states and territories participated in the interview. A variety of existing practices were identified, with few jurisdictions making systematic use of available data linkage infrastructure. Key barriers identified from the review included: a lack of perceived need; system factors; and resources. Existing regulatory tools enable data linkage to enhance communicable disease surveillance and control.

CONCLUSIONS

We identified considerable variation in the use of data linkage to inform communicable disease surveillance and control activities between jurisdictions. We suggest that routinely collected, disparate data are systematically integrated into existing surveillance and response policy cycle to improve communicable disease prevention and control efforts. Implications for public health: Existing gaps in communicable disease surveillance data may affect prevention and control efforts. Data linkage is recognised as a valuable method to close surveillance gaps and should be used to enhance the value of publicly held health data.

Role of viral and bacterial pathogens in causing pneumonia among Western Australian children: a case-control study protocol

INTRODUCTION

Pneumonia is the leading cause of childhood morbidity and mortality globally. Introduction of the conjugate Haemophilus influenzae B and multivalent pneumococcal vaccines in developed countries including Australia has significantly reduced the overall burden of bacterial pneumonia. With the availability of molecular diagnostics, viruses are frequently detected in children with pneumonia either as primary pathogens or predispose to secondary bacterial infection. Many respiratory pathogens that are known to cause pneumonia are also identified in asymptomatic children, so the true contribution of these pathogens to childhood community-acquired pneumonia (CAP) remains unclear. Since the introduction of pneumococcal vaccines, very few comprehensive studies from developed countries have attempted to determine the bacterial and viral aetiology of pneumonia. We aim to determine the contribution of bacteria and viruses to childhood CAP to inform further development of effective diagnosis, treatment and preventive strategies.

METHODS AND ANALYSIS

We are conducting a prospective case-control study (PneumoWA) where cases are children with radiologically confirmed pneumonia admitted to Princess Margaret Hospital for Children (PMH) and controls are healthy children identified from PMH outpatient clinics and from local community immunisation clinics. The case-control ratio is 1:1 with 250 children to be recruited in each arm. Nasopharyngeal swabs are collected from both cases and controls to detect the presence of viruses and bacteria by PCR; pathogen load will be assessed by quantitative PCR. The prevalence of pathogens detected in cases and controls will be compared, the OR of detection and population attributable fraction to CAP for each pathogen will be determined; relationships between pathogen load and disease status and severity will be explored.

ETHICS AND DISSEMINATION

This study has been approved by the human research ethics committees of PMH, Perth, Australia (PMH HREC REF 2014117EP). Findings will be disseminated at research conferences and in peer-reviewed journals.