Clinical and economic hospital burden of acute respiratory infection (BARI) due to respiratory syncytial virus in Spanish children, 2015-2018

Respiratory syncytial virus (RSV) is a leading cause of acute lower respiratory infection (ALRI) in children, causing frequent outpatient visits and hospitalizations. Our study aimed to describe the clinical and direct economic burden of ALRI hospitalizations related to RSV in children in Spain and the characteristics of patients and their episodes. In this retrospective study, ALRI hospitalizations in children aged < 5 years for 2015-2018 were reviewed using anonymized administrative public hospital discharge data from Spain. 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). The study reported a mean of 36,743 yearly admissions potentially due to RSV, resulting in a mean annual cost of €87.1 million. RSV-specific codes accounted for 39.2% of cases, unspecified acute bronchiolitis for 20.1%, and other unspecified ALRI codes for the remaining 40.6%. The mean hospitalization rate per 1,000 children was 55.5 in the first year of life, 16.0 in the second, and 5.4 between 24 and 59 months. A considerable proportion of cases occurred in children under two years old (> 80.4%) and even during the first year of life (> 61.7%). Otherwise healthy children accounted for 92.9% of hospitalizations and 83.3% of costs during the period. Children born preterm accounted for 1.3% of hospitalizations and 5.7% of costs. The findings revealed that RSV still contributes to a high burden on the Spanish health care system. Children under one year of age and otherwise healthy term infants accounted for most of the substantial clinical and economic burden of RSV. Current evidence potentially underestimates the true epidemiology and burden of severe RSV infection; thus, further studies focusing on the outpatient setting are needed.

Acute lower respiratory infections among children under five in Sub-Saharan Africa: a scoping review of prevalence and risk factors

BACKGROUND

Acute lower respiratory tract infections (ALRTIs) among children under five are still the leading cause of mortality among this group of children in low and middle-income countries (LMICs), especially countries in sub-Saharan Africa (SSA). This scoping review aims to map evidence on prevalence and risk factors associated with ALRTIs among children under 5 years to inform interventions, policies and future studies.

METHODS

A thorough search was conducted via four main databases (PubMed, JSTOR, Web of Science and Central). In all, 3,329 records were identified, and 107 full-text studies were considered for evaluation after vigorous screening and removing duplicates, of which 43 were included in this scoping review.

FINDINGS

Findings indicate a high prevalence (between 1.9% to 60.2%) of ALRTIs among children under five in SSA. Poor education, poverty, malnutrition, exposure to second-hand smoke, poor ventilation, HIV, traditional cooking stoves, unclean fuel usage, poor sanitation facilities and unclean drinking water make children under five more vulnerable to ALRTIs in SSA. Also, health promotion strategies like health education have doubled the health-seeking behaviours of mothers of children under 5 years against ALRTIs.

CONCLUSION

ALRTIs among children under five still present a significant disease burden in SSA. Therefore, there is a need for intersectoral collaboration to reduce the burden of ALRTIs among children under five by strengthening poverty alleviation strategies, improving living conditions, optimising child nutrition, and ensuring that all children have access to clean water. There is also the need for high-quality studies where confounding variables in ALRTIs are controlled.

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.

Three exposure metrics of size-specific particulate matter associated with acute lower respiratory infection hospitalization in children: A multi-city time-series analysis in China

BACKGROUND

The global burden of acute lower respiratory infection (ALRI) attributable to air pollution has increased in recent years, but the association between ALRI and exposure to size-specific particulate matter has not been investigated using different exposure metrics.

METHODS

We obtained ALRI admission from seven cities from 2014 to 2016 in China. Different sized particles were measured using three metrics (a) daily mean, (b) hourly peak, and (c) daily excessive concentration hours (DECH). Generalized additive models were fitted for each of the seven cities, and the city-specific estimates were then pooled using random-effects meta-analysis models. Stratified analyses were conducted to examine the effect modifications of gender, age, and season. We also estimated the disease burden due to particulate matter exposures.

RESULTS

There were 111,426 ALRI (79,803 pneumonia and 31,622 bronchiolitis) hospital admissions under the age of 15 between 2014 and 2016 in our study. Daily means were associated with the largest ALRI estimates (95% confidence interval [CI]): 2.43% (0.79%, 4.11%) for PM_2.5, 2.25% (0.11%, 4.44%) for PM_c, and 2.64% (0.73%, 4.58%) for PM₁₀. The magnitude of effect sizes were followed by DECH: 1.94% (0.51%, 3.39%) for PM_2.5, 0.88% (-0.14%, 1.92%) for PM_c, 1.86% (0.50%, 2.01%) for PM₁₀; and hourly peak: 0.70% (-0.60%, 2.01%) for PM_2.5, 1.05% (-0.13%, 2.66%) for PM_c, and 1.20% (-0.20%, 2.62%) for PM₁₀ at lag03. We found significantly higher effects in cold seasons than that in warm seasons, while we did not find a significant different between gender and age groups.

CONCLUSIONS

The adverse effects of exposure to particulate matter on ALRI hospitalizations are reconfirmed. DECH was a possible alternative exposure indicator for PM_2.5 assessment, which may affect air quality standards in the future.

Clinical manifestations and outcome of viral acute lower respiratory infection in hospitalised children in Myanmar

Background

Acute lower respiratory infection (ALRI) remains the leading cause of death in children worldwide, and viruses have been the major cause of ALRI. In Myanmar, ALRI is associated with high morbidity and mortality in children, and detailed information on ALRI is currently lacking.

Methods

This prospective study investigated the viral aetiologies, clinical manifestations, and outcomes of ALRI in hospitalised children aged 1 month to 12 years at the Yankin Children Hospital, Yangon, Myanmar from May 2017 to April 2019. The sample size was set to 300 patients for each year. Two nasopharyngeal swabs were obtained for the patients with suspected viral ALRI; one for rapid tests for influenza and respiratory syncytial virus (RSV), and the other for real-time PCR for the 16 ALRI-causing viruses. Pneumococcal colonization rates were also investigated using real-time PCR. Clinical information was extracted from the medical records, and enrolled patients were categorised by age and severity for comparison.

Results

Among the 5463 patients admitted with a diagnosis of ALRI, 570 (10.4%) were enrolled in this study. The median age of the patients was 8 months (interquartile range, 4–15 months). The most common symptoms were cough (93%) and difficulty in breathing (73%), while the most common signs of ALRI were tachypnoea (78%) and chest indrawing (67%). A total of 16 viruses were detected in 502 of 570 patients’ samples (88%), with RSV B (36%) and rhinovirus (28%) being the most commonly detected. Multiple viruses were detected in 221 of 570 samples (37%) collected from 570 patients. Severe ALRI was diagnosed in 107 of 570 patients (19%), and RSV B and human rhinovirus were commonly detected. The mortality rate was 5%; influenza virus A (29%) and RSV B (21%) were commonly detected, and stunting and lack of immunization were frequently observed in such cases. Additionally, 45% (259/570) of the patients had pneumococcal colonization.

Conclusions

Viral ALRI in hospitalised children with a median of 8 months has significant morbidity and mortality rates in Myanmar. RSV and rhinovirus were the most commonly detected from nasopharyngeal swabs, while influenza virus and RSV were the most frequently associated with fatal cases.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12879-022-07342-1.

The global burden of hospitalisation due to pneumonia caused by Staphylococcus aureus in the under-5 years children: A systematic review and meta-analysis

BACKGROUND

Pneumonia is a leading cause of childhood morbidity and mortality. This study aimed to estimate the global hospitalisation due to Staphylococcus aureus pneumonia in under-5 children.

METHODS

We conducted a systematic review and meta-analysis of primary studies following the PRISMA-P guidelines. We searched Medline, Embase, Global Health, CINAHL, Global Index Medicus, Scopus, China National Knowledge Infrastructure, Wanfang, and CQvip. We included studies reporting data on Staphylococcus aureus pneumonia, confirmed by detection of the pathogen in sterile-site samples in under-5 hospitalised children, published in English or Chinese language and conducted between 1st January 1990 and 4th November 2021 and between 1st January 1990 and 30th September 2020, respectively. We excluded those testing upper respiratory tract samples and not reporting data on samples with other bacteria or absence of bacteria. We screened papers against pre-specified criteria, extracted data and assessed the bacteriological quality, and combined epidemiological and microbiological quality of studies using two self-designed checklists. Pooled proportions of hospitalisation episodes for Staphylococcus aureus pneumonia amongst all-cause pneumonia and the 95% confidence intervals were calculated using the random-effects model. The review protocol was registered on PROSPERO (CRD42021236606).

FINDINGS

Of 26,218 studies identified, thirty-five studies enroling 20,708 hospitalised pneumonia episodes were included. Out of the total hospitalised pneumonia cases in this population, the pooled proportion of Staphylococcal pneumonia cases was 3% (95% CI 2% to 4%; I²=96%). amongst 12 studies with higher microbiological quality, the pooled estimate was 6% (95% CI 2% to 10%; I²= 98%). Based on the recent global estimates of hospitalised pneumonia in this age group, the 3% and 6% estimates represent 738 thousand and 1.48 million hospitalisations in 2019, respectively. Based on the Grading of Recommendations Assessment, Development, and Evaluation (GRADE), the overall quality of evidence was considered to be moderate.

INTERPRETATION

Our findings are probably an underestimate because of the unknown and the likely limited sensitivity of current testing methods for Staphylococcal pneumonia diagnosis and widespread reported use of antibiotics before recruitment (in 46% of cases). Staphylococcus aureus is an important cause of hospitalisation for pneumonia in young children globally.

FUNDING

Bill and Melinda Gates Foundation (OPP 1,172,551) through a prime award to John Hopkins University.

The association between fine particulate matter and acute lower respiratory infections in Yancheng City, China

Due to the rapid economic development and acceleration of industrialization, most cities in China are experiencing severe air pollution. Exposure to fine particulate matter (PM_2.5) has been associated with acute lower respiratory tract infection (ALRI). To estimate associations between short-term exposure to PM_2.5 and ALRI hospitalization in Yancheng City, China. This was a 6-year time-series study from 2014 to 2019. Data on hospitalization were collected from four high-ranked general hospitals, including for community-acquired pneumonia (CAP), acute exacerbation of chronic bronchitis (AECB), acute exacerbation of chronic obstructive pulmonary disease (AECOPD), and acute exacerbation of bronchiectasis (AEB), and the sum was termed total ALRIs. We obtained pollutant exposure data from five fixed monitoring stations. The association between PM_2.5 and ALRI hospitalization was estimated using the generalized linear model with quasi-Poisson regression. Two-pollutant models were applied to test the robustness of the observed correlations. Subgroup analyses included sex, age, and season. During the study period, a total of 43,283 cases of total ALRIs were recorded. The average annual mean PM_2.5 concentration was 45.4 ± 32.3 μg/m³. A 10-μg/m³ increase in PM_2.5 concentration (lag 0) was significantly associated with increases in hospitalizations for total ALRIs (at 0.73%; 95% CI: 0.40%, 1.06%), in CAP (at 0.80%; 95% CI: 0.02%, 1.57%), in for AECOPD (1.08%; 95% CI: 0.38%, 1.78%), and AECB (0.67%; 95% CI: 0.23%, 1.11%). The estimated effects for total ALRIs and AECB were relatively robust with adjustment for other air pollutants. Associations between PM_2.5 and total ALRIs were stronger in females, in the elderly, and in the cold season. PM_2.5 exposure was significantly associated with ALRI morbidity, and females and older people were more susceptible to PM_2.5 air pollution, especially in the cold season.

Cost-effectiveness of strategies for preventing paediatric lower respiratory infections associated with respiratory syncytial virus in eight Chinese cities

BACKGROUND

New monoclonal antibodies (mAbs) and vaccines against RSV with promising efficacy and protection duration are expected to be available in the near future. We evaluated the cost-effectiveness of the administration of maternal immunisation (MI), infant mAb (IA) and paediatric immunisation (PI) as well as their combinations in eight Chinese cities.

METHODS

We used a static model to estimate the impact of these preventive interventions on reducing the burden of RSV-ALRI in twelve monthly birth cohorts from a societal perspective. In addition to year-round administration, we also considered seasonal administration of MI and IA (i.e., administered only to children born in selected months). The primary outcome was threshold strategy cost (TSC), defined as the maximum costs per child for a strategy to be cost-effective.

RESULTS

With a willingness-to-pay threshold of one national GDP per capita per QALY gained for all the cities, TSC of year-round strategies was: (i) US$2.4 (95% CI: 1.9-3.4) to US$14.7 (11.6-21.4) for MI; (ii) US$19.9 (16.9-25.9) to US$144.2 (124.6-184.7) for IA; (iii) US$28.7 (22.0-42.0) to US$201.0 (156.5-298.6) for PI; (iv) US$31.1 (24.0-45.5) to US$220.7 (172.0-327.3) for maternal plus paediatric immunisation (MPI); and (v) US$41.3 (32.6-58.9) to US$306.2 (244.1-441.3) for infant mAb plus paediatric immunisation (AP). In all cities, the top ten seasonal strategies (ranked by TSC) protected infants from 5 or fewer monthly birth cohorts.

CONCLUSIONS

Administration of these interventions could be cost-effective if they are suitably priced. Suitably-timed seasonal administration could be more cost-effective than their year-round counterpart. Our results can inform the optimal strategy once these preventive interventions are commercially available.

Effect of improved cookstove intervention on childhood acute lower respiratory infection in Northwest Ethiopia: a cluster-randomized controlled trial

BACKGROUND

Household air pollution exposure is linked with over 3.5 million premature deaths every year, ranking highest among environmental risk factors globally. Children are uniquely vulnerable and sensitive to the damaging health effects of household air pollution which includes childhood acute lower respiratory infection (ALRI). The use of improved cookstoves has been widely encouraged to reduce these health burdens. It is, however, unclear as to whether it is possible to prevent household air pollution-related disease burdens with biomass-fuelled improved cookstove intervention and the evidence regarding its child health effect still attracts wide debate. Therefore, we investigated the child health effect of improved baking stove intervention compared with the continuation of the open burning traditional baking stove.

METHODS

A cluster-randomized controlled trial was conducted to assess the health effect of improved baking stove intervention. A total of 100 clusters were randomly allocated to both arms at a 1:1 ratio, and a total of four follow-up visits were carried out within 1 year immediately after the delivery of the intervention to all households allocated into the intervention arm. Data were analyzed in SPSS-22, and the intervention effect was estimated using a Generalized Estimating Equations modeling approach among the intention-to-treat population.

RESULTS

A total of 5508 children were enrolled in the study across 100 randomly selected clusters in both arms, among which data were obtained from a total of 5333 participants for at least one follow-up visit which establishes the intention-to-treat population dataset. The intervention was not found to have a statistically significant effect on the longitudinal childhood ALRI with an estimated odds ratio of 0.95 (95% CI: 0.89-1.02). Nevertheless, the longitudinal change in childhood ALRI was significantly associated with age, baseline childhood ALRI, location of cooking quarter, secondary stove type and frequency of baking event measured at baseline.

CONCLUSIONS

We found no evidence that an intervention comprising biomass-fuelled improved baking stove reduced the risk of childhood ALRI compared with the continuation of an open burning traditional baking stove. Therefore, effective cooking solutions are needed to avert the adverse health effect of household air pollution, particularly, childhood ALRI.

TRIAL REGISTRATION

The trial was registered on August 2, 2018 at clinical trials.gov registry database (registration identifier number: NCT03612362).

Clinical impact of rapid viral respiratory panel testing on pediatric critical care of patients with acute lower respiratory infection

BACKGROUND

We aimed to determine the impact of utilizing a rapid panel test of respiratory viral and atypical bacteria (FilmArray® Respiratory Panel, FA RP) on etiological diagnosis of acute lower respiratory infection (ALRI) and antimicrobial stewardship in critical care pediatric patients.

METHODS

Prospective cohort study of patients aged<18 years with clinical diagnosis of ALRI that were admitted to the Pediatric Intensive Care Unit (PICU) of Hospital Sant Joan de Deu (Barcelona, Spain) during December 2015-February 2017. Patients were diagnosed by FA RP and by a bundle of routine microbiological assays.

RESULTS

ALRI viral and bacterial etiology was confirmed by a composite reference standard of routine microbiological assays in 72 (55.4%) and 15 (11.5%) respiratory samples, respectively, that were collected from 130 children (median age, 3.5 months, IQR 1.1-14.8 months; 54.6% male). Comparatively, FA RP use increased etiological confirmation of ALRI in up to 123 (94.6%) samples (p<0.001) but only determined a bacterial origin in 2 (1.5%). Availability of diagnostic results before patient discharge from the PICU rose from 65.4 to 38.5% (p<0.001). Use of the new panel test directly influenced antimicrobial stewardship in 11 (8.4%) episodes, leading to discontinuation of antiviral drugs (n=5), administration of targeted antibiotics (n=3), antiviral therapy start (n=2) and both targeted antibiotic administration and discontinuation of antiviral drugs (n=1).

CONCLUSION

FA RP contributed to improve etiological diagnosis of ALRI in a timely manner while enhancing a more rational use of antimicrobial drugs in critical care pediatric patients.

IL-33 and ST2 as predictors of disease severity in children with viral acute lower respiratory infection

BACKGROUND

Mechanisms influencing severity of acute lower respiratory infection (ALRI) in children are not established. We aimed to assess the role of inflammatory markers and respiratory viruses in ALRI severity.

METHODS

Concentrations of interleukin(IL)-33, soluble suppression of tumorigenicity (sST)2, IL-1ß, tumor necrosis factor α, IL-4, IL-6 and IL- 8 and types of respiratory viruses were evaluated in children at the first and fifth days after hospital admission. Disease severity was defined as need for mechanical ventilation.

RESULTS

Seventy-nine children <5 years-old were included; 33(41.8%) received mechanical ventilation. No associations between virus type, viral load or co-detections and severity of disease were observed. Detection of IL-33 and sST2 in nasopharyngeal aspirates (NPA) on admission were associated with higher risk for mechanical ventilation (RR = 2.89 and RR = 4.57, respectively). IL-6 and IL-8 concentrations were higher on Day 5 in mechanically ventilated children. IL-6 NPA concentrations decreased from Day 1 to Day 5 in children who did not receive mechanical ventilation. Increase in sST2 NPA concentrations from Day 1 to Day 5 was associated with longer hospital length of stay (p < 0.01).

CONCLUSIONS

An exacerbated local activation of the IL-33/ST2 axis and persistently high sST2 concentrations over time were associated with severity of viral ALRI in children.

Respiratory syncytial virus infections in India: Epidemiology and need for vaccine

Respiratory syncytial virus (RSV) has been identified as a leading cause of lower respiratory tract infections in young children and elderly. It is an enveloped negative-sense RNA virus belonging to Genus Orthopneumovirus. The clinical features of RSV infection range from mild upper-respiratory-tract illnesses or otitis media to severe lower-respiratory-tract illnesses. Current estimates show that about 33.1 million episodes of RSV-acute lower respiratory infection (ALRI) occurred in young children in 2015, of these majority that is, about 30 million RSV-ALRI episodes occurred in low-middle-income countries. In India, the rates of RSV detection in various hospital- and community-based studies mostly done in children vary from 5% to 54% and from 8% to 15%, respectively. Globally, RSV epidemics start in the South moving to the North. In India, RSV mainly peaks in winter in North India and some correlation with low temperature has been observed. Different genotypes of Group A (GA2, GA5, NA1 and ON1) and Group B (GB2, SAB4 and BA) have been described from India. The burden of RSV globally has kept it a high priority for vaccine development. After nearly 50 years of attempts, there is still no licensed vaccine and challenges to obtain a safe and effective vaccine is still facing the scientific community. The data in this review have been extracted from PubMed using the keywords RSV and Epidemiology and India. The data have been synthesised by the authors.

Tuberculosis case finding: Supplement intensified case finding among acute lower respiratory infection (ALRI) hospitalized patients in Sa Kaeo province, Thailand

BACKGROUND AND PURPOSE

We aimed to estimate TB prevalence among in-patients hospitalized with acute lower respiratory infection (ALRI) through a routine TB case finding approach (Patient-Initiated-Pathway, PIP) and among those without initial TB detection by PIP using a supplementary-Intensified-Case-Finding (supplementary-ICF) approach to determine the extent of active TB infection in patients enrolled in population-based surveillance in Sa Keao, Thailand. We also investigated secondary TB transmission through household contacts (HHCs).

METHODS

This was a prospective cross-sectional study. Data for hospitalized patients with ALRI were obtained from population-based pneumonia surveillance. PIP was provided in ALRI patients with suspected TB infection; those without initial suspicion of TB infection were evaluated for TB by the supplementary-ICF approach. For each active TB case finding approach, index cases were identified by acid-fast-bacillus testing and the TB prevalence was estimated. HHCs of each TB index case were followed to identify the extent of secondary TB infection.

RESULTS

TB prevalence among ALRI hospitalized patients was 12.2% among those undergoing PIP and 6.8% among those undergoing supplementary-ICF. The total number of active TB cases was doubled after implementing the supplementary-ICF method. Secondary TB infection among HHCs was 3.5 times more common for contacts of index cases identified by routine active TB case finding compared to supplementary-ICF TB.

CONCLUSION

Supplementary-ICF among ALRI hospitalizations would be expected to result in improved active TB case detection compared to the current policy of PIP. The supplementary-ICF also enhanced early case detection and showed lower prevalence of secondary infection.

Epidemiology and burden of influenza in healthy children aged 6 to 35 months: analysis of data from the placebo arm of a phase III efficacy trial

Background

Despite World Health Organization recommendations, in many countries young children are not targeted for influenza vaccination. To help inform influenza vaccination policy, we examined the occurrence and burden of influenza in healthy children aged 6 to 35 months using data from a recent phase III placebo-controlled influenza vaccine trial conducted in countries in the Northern and Southern Hemispheres.

Methods

This was an analysis of data from participants included in the placebo arm of a phase III clinical trial in healthy children aged 6 to 35 months (EudraCT no. 2013–001231-51). Included children had never been vaccinated for influenza and were observed for one influenza season. Outcome measures included the occurrence of influenza-like illness (ILI), laboratory-confirmed influenza, virus types/subtypes, severe symptoms and complications of confirmed influenza, and healthcare use associated with confirmed influenza.

Results

Data from 2210 participants were analysed. ILI was reported for 811 participants (36.7%). Of these, 255 participants (31.4%) had 263 virologically confirmed episodes of influenza. The overall influenza attack rate was 11.5%. The most common influenza virus detected was A(H3N2) (40.7%), followed by B/Yamagata (23.6%), A(H1N1) (18.6%), and B/Victoria (8.0%). Grade 3 fever was reported in 24.3% of confirmed episodes, acute lower respiratory infection in 8.7%, acute otitis media in 6.1%, and pneumonia in 1.9%. In most influenza episodes (93.2%), antipyretics, analgesics, or non-steroidal anti-inflammatory drugs were taken. Antibiotics were prescribed for 41.4% of influenza episodes. More than half of the influenza episodes (57.0%) resulted in outpatient visits. Influenza resulted in overnight hospitalisation in 1.1% of episodes.

Conclusions

Influenza is associated with a significant burden of disease in healthy children. This analysis also revealed that antibiotics continue to be frequently used for young children with influenza.

Trial registration

EudraCT no. 2013–001231-51.

Electronic supplementary material

The online version of this article (10.1186/s12879-019-3920-8) contains supplementary material, which is available to authorized users.

Association of ambient air pollution with lengths of hospital stay for hanoi children with acute lower-respiratory infection, 2007-2016

INTRODUCTION

The association between ambient air pollution and length of hospital stay (LOS) for children with lower-respiratory infection is unclear.

MATERIALS AND METHODS

The association was examined using admission data for 75,432 children in Hanoi, aged 0-5 years, hospitalized with acute lower-respiratory infection (ALRI) and daily air pollutant levels in Hanoi between 2007 and 2016. We estimated the odds ratio of being discharged for an interquartile range (IQR) increment (IQR) of ambient pollutants during one to four days prior to admission date. We used pooled logistic regression models including a B-spline function of calendar time and terms describing the baseline odds, adjusting for meteorological factors, age, gender, residential location, week-day of admission, discharge on weekends or holidays, and number of respiratory hospitalizations one day prior to the discharge date.

RESULTS

An IQR increase in O₃ concentrations (85.8 μg/m³) was associated with a 5% (95%CI: 2%-8%) decrease in the odds of discharge from hospital among children with ALRI. Results were similar for PM₁₀, but only for children aged 2-5 years. For the other pollutants, corresponding associations were close to null or in the opposite direction. For example, increase in CO was associated with shorter LOS.

CONCLUSIONS

Our study provides the first investigation of the associations between lengths of hospital stays and air pollutant levels prior to hospitalization in Asian children. Increased levels of O₃ prior to admission predicted prolonged hospitalizations. The inconsistencies in the findings for other pollutants call for further investigations.

Impact of the 23-valent pneumococcal polysaccharide vaccination in pregnancy against infant acute lower respiratory infections in the Northern Territory of Australia

BACKGROUND

Indigenous children in Australia's Northern Territory are densely colonised with the pneumococcus within weeks of birth antecedent to a high prevalence of acute lower respiratory infection (ALRI). We assessed the impact of the 23-valent pneumococcal polysaccharide vaccine (23vPPV) in pregnancy against infant ALRI in this setting.

METHODS

In an open label, allocation concealed, outcome-assessor blinded, randomised controlled trial conducted in the Northern Territory of Australia, healthy Indigenous women aged 17-39 years were randomised to receive the 23vPPV during pregnancy (n = 75; 30-36 weeks gestation), at birth (n = 75), or at 7 months post-partum (n = 77). Randomisation was stratified by community of residence. In a secondary analysis, we compared the incidence of ALRI hospitalisations and ALRI clinic presentations (ascertained from electronic medical records) among infants of pregnancy vaccinees versus infants of mothers not vaccinated in pregnancy (controls) in the first year of life.

RESULTS

ALRI hospitalisation incidence was 12.3 per 100 child-years among infants of pregnancy vaccinees compared with 15.8 per 100 child-years among controls (hazard ratio (HR) 0.77, 95%CI 0.29-2.03). ALRI hospitalisations were more common among remote compared to urban infants (27.7 versus 8.6 per 100 child-years). Stratification by dwelling highlighted a differential antenatal vaccine effect against ALRI hospitalisations (urban HR 2.45, 95%CI 0.60-9.99; remote HR 0.21, 95%CI 0.04-1.08). ALRI clinic presentation incidence was similar among infants of pregnancy vaccinees and controls.

CONCLUSIONS

In this small study, antenatal 23vPPV vaccination was not associated with a reduced incidence of infant ALRI hospitalisations or ALRI clinic presentations during the first year of life. A potential differential effect between urban and remote settings warrants further investigation.

TRIAL REGISTRATION

PneuMum; ClinicalTrials.gov NCT00714064.

Bacteria and viruses in the nasopharynx immediately prior to onset of acute lower respiratory infections in Indigenous Australian children

Acute lower respiratory infection (ALRI) is a major cause of hospitalization for Indigenous children in remote regions of Australia. The associated microbiology remains unclear. Our aim was to determine whether the microbes present in the nasopharynx before an ALRI were associated with its onset. A retrospective case-control/crossover study among Indigenous children aged up to 2 years. ALRI cases identified by medical note review were eligible where nasopharyngeal swabs were available: (1) 0–21 days before ALRI onset (case); (2) 90–180 days before ALRI onset (same child controls); and (3) from time and age-matched children without ALRI (different child controls). PCR assays determined the presence and/or load of selected respiratory pathogens. Among 104 children (182 recorded ALRI episodes), 120 case-same child control and 170 case-different child control swab pairs were identified. Human adenoviruses (HAdV) were more prevalent in cases compared to same child controls (18 vs 7%; OR = 3.08, 95% CI 1.22–7.76, p = 0.017), but this association was not significant in cases versus different child controls (15 vs 10%; OR = 1.93, 95% CI 0.97–3.87 (p = 0.063). No other microbes were more prevalent in cases compared to controls. Streptococcus pneumoniae (74%), Haemophilus influenzae (75%) and Moraxella catarrhalis (88%) were commonly identified across all swabs. In a pediatric population with a high detection rate of nasopharyngeal microbes, HAdV was the only pathogen detected in the period before illness presentation that was significantly associated with ALRI onset. Detection of other potential ALRI pathogens was similar between cases and controls.

Air pollution and hospital visits for acute upper and lower respiratory infections among children in Ningbo, China: A time-series analysis

Acute upper and lower respiratory infections are main causes of mortality and morbidity in children. Air pollution has been recognized as an important contributor to development and exacerbation of respiratory infections. However, few studies are available in China. In this study, we investigated the short-term effect of air pollution on hospital visits for acute upper and lower respiratory infections among children under 15 years in Ningbo, China. Poisson generalized models were used to estimate the associations between air pollution and hospital visits for acute upper and lower respiratory infections adjusted for temporal, seasonal, and meteorological effects. We found that four pollutants (PM_2.5, PM₁₀, NO₂, and SO₂) were significantly associated with hospital visits for acute upper and lower respiratory infections. The effect estimates for acute upper respiratory infections tended to be higher (PM_2.5 ER = 3.46, 95% CI 2.18, 4.76; PM₁₀ ER = 2.81, 95% CI 1.93, 3.69; NO₂ ER = 11.27, 95% CI 8.70, 13.89; SO₂ ER = 15.17, 95% CI 11.29, 19.19). Significant associations for gaseous pollutants (NO₂ and SO₂) were observed after adjustment for particular matter. Stronger associations were observed among older children and in the cold period. Our study suggested that short-term exposure to outdoor air pollution was associated with hospital visits for acute upper and lower respiratory infections in Ningbo.

Effects of health intervention programs and arsenic exposure on child mortality from acute lower respiratory infections in rural Bangladesh

BACKGROUND

Respiratory infections continue to be a public health threat, particularly to young children in developing countries. Understanding the geographic patterns of diseases and the role of potential risk factors can help improve future mitigation efforts. Toward this goal, this paper applies a spatial scan statistic combined with a zero-inflated negative-binomial regression to re-examine the impacts of a community-based treatment program on the geographic patterns of acute lower respiratory infection (ALRI) mortality in an area of rural Bangladesh. Exposure to arsenic-contaminated drinking water is also a serious threat to the health of children in this area, and the variation in exposure to arsenic must be considered when evaluating the health interventions.

METHODS

ALRI mortality data were obtained for children under 2 years old from 1989 to 1996 in the Matlab Health and Demographic Surveillance System. This study period covers the years immediately following the implementation of an ALRI control program. A zero-inflated negative binomial (ZINB) regression model was first used to simultaneously estimate mortality rates and the likelihood of no deaths in groups of related households while controlling for socioeconomic status, potential arsenic exposure, and access to care. Next a spatial scan statistic was used to assess the location and magnitude of clusters of ALRI mortality. The ZINB model was used to adjust the scan statistic for multiple social and environmental risk factors.

RESULTS

The results of the ZINB models and spatial scan statistic suggest that the ALRI control program was successful in reducing child mortality in the study area. Exposure to arsenic-contaminated drinking water was not associated with increased mortality. Higher socioeconomic status also significantly reduced mortality rates, even among households who were in the treatment program area.

CONCLUSION

Community-based ALRI interventions can be effective at reducing child mortality, though socioeconomic factors may continue to influence mortality patterns. The combination of spatial and non-spatial methods used in this paper has not been applied previously in the literature, and this study demonstrates the importance of such approaches for evaluating and improving public health intervention programs.

Prevalence and predictors of hypoxaemia in respiratory and non-respiratory primary diagnoses among emergently ill children at a tertiary hospital in south western Nigeria

BACKGROUND

Hypoxaemia is a potentially harmful complication of both acute lower respiratory tract infections (ALRI) and non-ALRI in children but its contribution to burden and outcomes of hospital admissions in Africa is unclear. We investigated prevalence and predictors of hypoxaemia in ALRI and non-ALRI according to age and primary diagnoses in emergently ill children in south western Nigeria.

METHODS

In 1726 emergently ill children admitted to a tertiary hospital in Ibadan, south western Nigeria, oxygen saturation was measured shortly after admission. Hypoxaemia was defined as oxygen saturation <90%. Clinical features and the primary admission diagnoses were recorded. Prevalence of hypoxaemia according to age and diagnoses was calculated. Symptoms and signs associated with hypoxaemia were compared between children with ALRI and those with non-ALRI.

RESULTS

Hypoxaemia was detected in 28.6% (494/1726) of admissions. Prevalence of hypoxaemia varied in different conditions: it was 49.2% (154/313) in ALRI, 41.1% (188/454) in neonates, 27.2% (6/22) in post-neonatal tetanus, 23.3% (14/60) in sickle cell anaemia, 22.6% (38/168) in septicaemia and 14.4% (76/527) of malaria cases. Nasal flaring (OR 3.86; 95% CI 1.70 to 8.74) and chest retraction (OR 4.77; 95% CI 1.91 to 11.92) predicted hypoxaemia in ALRI but not in non-ALRI.

CONCLUSIONS

Hypoxaemia is common among Nigerian children admitted to an emergency unit and is associated with a poor outcome irrespective of primary admission diagnosis. Provision of equipment to measure oxygen saturation and facilities for effective oxygen delivery might substantially reduce mortality.

Respiratory virus infections in hospitalized children and adults in Lao PDR

Background

Acute respiratory infections are an important cause of morbidity and mortality worldwide, with a major burden of disease in developing countries. The relative contribution of viruses in acute lower respiratory infections (ALRI) is, however, poorly documented in Lao PDR.

Objective

The objective of this study is to investigate the etiology of ALRI in patients of all ages in two hospitals of Laos.

Methods

Multiplex PCR/RT‐PCR methods were used to target 18 major common respiratory viruses. Between August 2009 and October 2010, samples from 292 patients presenting with ALRI were collected.

Results and conclusion

Viruses were detected in 162 (55%) samples. In 48% (140/292) of the total ALRI cases, a single virus was detected while coinfections were observed in 8% (22/292) of the samples. The most frequent viruses were rhinovirus/enterovirus (35%), human respiratory syncytial virus (26%), and influenza viruses (13%). Parainfluenza viruses were detected in 9%, adenovirus in 6%, human metapneumovirus in 4%, coronaviruses (229E, NL63, OC43, HKU1) in 4%, and bocavirus in 3% of ALRI specimens. Most viral infections occurred in patients below 5 years of age. The distribution of viruses varied according to age‐groups. No significant correlation was observed between the severity of the disease and the age of patients or the virus species. This study provides the description of viral etiology among patients presenting with ALRI in Lao PDR. Additional investigations are required to better understand the clinical role of the different viruses and their seasonality in Laos.