Risk factors for community-acquired pneumonia in pre-school-aged children

Health effects associated with exposure to secondhand smoke: a Burden of Proof study

Despite a gradual decline in smoking rates over time, exposure to secondhand smoke (SHS) continues to cause harm to nonsmokers, who are disproportionately children and women living in low- and middle-income countries. We comprehensively reviewed the literature published by July 2022 concerning the adverse impacts of SHS exposure on nine health outcomes. Following, we quantified each exposure-response association accounting for various sources of uncertainty and evaluated the strength of the evidence supporting our analyses using the Burden of Proof Risk Function methodology. We found all nine health outcomes to be associated with SHS exposure. We conservatively estimated that SHS increases the risk of ischemic heart disease, stroke, type 2 diabetes and lung cancer by at least around 8%, 5%, 1% and 1%, respectively, with the evidence supporting these harmful associations rated as weak (two stars). The evidence supporting the harmful associations between SHS and otitis media, asthma, lower respiratory infections, breast cancer and chronic obstructive pulmonary disease was weaker (one star). Despite the weak underlying evidence for these associations, our results reinforce the harmful effects of SHS on health and the need to prioritize advancing efforts to reduce active and passive smoking through a combination of public health policies and education initiatives.

Impact of indoor environment on children's pulmonary health

INTRODUCTION

A child's living environment has a significant impact on their respiratory health, with exposure to poor indoor air quality (IAQ) contributing to potentially lifelong respiratory morbidity. These effects occur throughout childhood, from the antenatal period through to adolescence. Children are particularly susceptible to the effects of environmental insults, and children living in socioeconomic deprivation globally are more likely to breathe air both indoors and outdoors, which poses an acute and long-term risk to their health. Adult respiratory health is, at least in part, determined by exposures and respiratory system development in childhood, starting in utero.

AREAS COVERED

This narrative review will discuss, from a global perspective, what contributes to poor IAQ in the child's home and school environment and the impact that indoor air pollution exposure has on respiratory health throughout the different stages of childhood.

EXPERT OPINION

All children have the right to a living and educational environment without the threat of pollution affecting their health. Action is needed at multiple levels to address this pressing issue to improve lifelong respiratory health. Such action should incorporate a child's rights-based approach, empowering children, and their families, to have access to clean air to breathe in their living environment.

Does attendance in outdoor kindergartens reduce the use of antibiotics in children?

AIM

The aim of this study was to determine whether children enrolled in rural outdoor kindergartens had a lower risk of redeeming at least one prescription for antibiotics compared with children enrolled in urban conventional kindergartens, and if type of antibiotics prescribed differed according to kindergarten type.

METHODS

Two Danish municipalities provided data including civil registration numbers from children enrolled in a rural outdoor kindergarten in 2011-2019, and a subsample of all children enrolled in urban conventional kindergartens in the same period. Civil registration numbers were linked to individual-level information on redeemed prescriptions for antibiotics from the Danish National Prescription Registry. Regression models were performed on 2132 children enrolled in outdoor kindergartens, and 2208 children enrolled in conventional kindergartens.

RESULTS

There was no difference between groups in risk of redeeming at least one prescription for all types of antibiotics (adjusted risk ratio: 0.97 [95% confidence intervals 0.93, 1.02, p = 0.26]). Similarly, there were no differences between kindergarten type and risk of redeeming at least one prescription for systemic, narrow-spectrum systemic antibacterial, broad-spectrum systemic antibacterial or topical antibiotics.

CONCLUSION

Compared with children who were enrolled in conventional kindergartens, children who were enrolled in outdoor kindergartens did not have a lower risk of redeeming prescriptions for any type of antibiotics.

The impact of poor housing and indoor air quality on respiratory health in children

It is becoming increasingly apparent that poor housing quality affects indoor air quality, significantly impacting on respiratory health in children and young people. Exposure to damp and/or mould in the home, cold homes and the presence of pests and pollutants all have a significant detrimental impact on child respiratory health. There is a complex relationship between features of poor-quality housing, such as being in a state of disrepair, poor ventilation, overcrowding and being cold, that favour an environment resulting in poor indoor air quality. Children living in rented (private or public) housing are more likely to come from lower-income backgrounds and are most at risk of living in substandard housing posing a serious threat to respiratory health. Children have the right to safe and adequate housing, and research has shown that either rehousing or making modifications to poor-quality housing to improve indoor air quality results in improved respiratory health. Urgent action is needed to address this threat to health. All stakeholders should understand the relationship between poor-quality housing and respiratory health in children and act, working with families, to redress this modifiable risk factor.

Educational aims

The reader should understand how housing quality and indoor air quality affect respiratory health in children.The reader should understand which children are at most risk of living in poor-quality housing.The reader should understand what policy recommendations have been made and what actions need to be undertaken to improve housing quality and respiratory health in children and young people.

Childhood lower respiratory tract infections linked to residential airborne bacterial and fungal microbiota

Residential microbial composition likely contributes to the development of lower respiratory tract infections (LRTI) among children, but the association is poorly understood. We aimed to study the relationship between the indoor airborne dust bacterial and fungal microbiota and childhood LRTI in Ibadan, Nigeria. Ninety-eight children under the age of five years hospitalized with LRTI were recruited and matched by age (±3 months), sex, and geographical location to 99 community-based controls without LRTI. Participants' homes were visited and sampled over a 14-day period for airborne house dust using electrostatic dustfall collectors (EDC). In airborne dust samples, the composition of bacterial and fungal communities was characterized by a meta-barcoding approach using amplicons targeting simultaneously the bacterial 16S rRNA gene and the internal-transcribed-spacer (ITS) region-1 of fungi in association with the SILVA and UNITE database respectively. A 100-unit change in house dust bacterial, but not fungal, richness (OR 1.06; 95%CI 1.03-1.10) and a 1-unit change in Shannon diversity (OR 1.92; 95%CI 1.28-3.01) were both independently associated with childhood LRTI after adjusting for other indoor environmental risk factors. Beta-diversity analysis showed that bacterial (PERMANOVA p < 0.001, R² = 0.036) and fungal (PERMANOVA p < 0.001, R² = 0.028) community composition differed significantly between homes of cases and controls. Pair-wise differential abundance analysis using both DESEq2 and MaAsLin2 consistently identified the bacterial phyla Deinococcota (Benjamini-Hochberg (BH) adjusted p-value <0.001) and Bacteriodota (BH-adjusted p-value = 0.004) to be negatively associated with LRTI. Within the fungal microbiota, phylum Ascomycota abundance (BH adjusted p-value <0.001) was observed to be directly associated with LRTI, while Basidiomycota abundance (BH adjusted p-value <0.001) was negatively associated with LRTI. Our study suggests that early-life exposure to certain airborne bacterial and fungal communities is associated with LRTI among children under the age of five years.

Exposure-response relationship of residential dampness and mold damage with severe lower respiratory tract infections among under-five children in Nigeria

Previous epidemiological studies demonstrated an increased risk of respiratory health effects in children and adults exposed to dampness or mold. This study investigated associations of quantitative indicators of indoor dampness and mold exposure with severe lower respiratory tract infections (LRTI) among children aged 1-59 months in Ibadan, Nigeria.

Methods

In-home visits were conducted among 178 children hospitalized with LRTI matched by age (±3 months), sex, and geographical location with 180 community-based children without LRTI. Trained study staff evaluated the indoor environment using a standardized home walkthrough checklist and measured visible dampness and mold damage. Damp-moldy Index (DMI) was also estimated to quantify the level of exposure. Exposure-response relationships of dampness and mold exposure with severe LRTI were assessed using multivariable restricted cubic spline regression models adjusting for relevant child, housing, and environmental characteristics.

Results

Severe LRTI cases were more often male than female (61.8%), and the overall mean (SD) age was 7.3 (1.35) months. Children exposed to dampness <0.3 m² (odds ratio [OR] = 2.11; 95% confidence interval [CI] = 1.05, 4.36), and between 0.3 and 1.0 m² (OR = 2.34; 95% CI = 1.01, 7.32), had a higher odds of severe LRTI compared with children not exposed to dampness. The restricted cubic spline showed a linear exposure-response association between severe LRTI and residential dampness (P < 0.001) but a nonlinear relationship with DMI (P = 0.01).

Conclusions

Residential dampness and DMI were exposure-dependently associated with higher odds of severe LRTI among under-five children. If observed relationships were causal, public health intervention strategies targeted at reducing residential dampness are critically important to mitigate the burden of severe LRTI among under-five children.

Indoor bacterial and fungal aerosols as predictors of lower respiratory tract infections among under-five children in Ibadan, Nigeria

BACKGROUND

This study aimed to investigate the association between exposure to diverse indoor microbial aerosols and lower respiratory tract infections (LRTI) among children aged 1 to 59 months in Ibadan, Nigeria.

METHODS

One hundred and seventy-eight (178) hospital-based LRTI cases among under-five children were matched for age (± 3 months), sex and geographical location with 180 community-based controls (under-five children without LRTI). Following consent from caregivers of eligible participants, a child's health questionnaire, clinical proforma and standardized home-walkthrough checklist were used to collect data. Participant homes were visited and sampled for indoor microbial exposures using active sampling approach by Anderson sampler. Indoor microbial count (IMC), total bacterial count (TBC), and total fungal count (TFC) were estimated and dichotomized into high (> median) and low (≤ median) exposures. Alpha diversity measures including richness (R), Shannon (H) and Simpson (D) indices were also estimated. Conditional logistic regression models were used to test association between exposure to indoor microbial aerosols and LRTI risk among under-five children.

RESULTS

Significantly higher bacterial and fungal diversities were found in homes of cases (R = 3.00; H = 1.04; D = 2.67 and R = 2.56; H = 0.82; D = 2.33) than homes of controls (R = 2.00; H = 0.64; D = 1.80 and R = 1.89; H = 0.55; D = 1.88) p < 0.001, respectively. In the multivariate models, higher categories of exposure to IMC (aOR = 2.67, 95% CI 1.44-4.97), TBC (aOR = 2.51, 95% CI 1.36-4.65), TFC (aOR = 2.75, 95% CI 1.54-4.89), bacterial diversity (aOR = 1.87, 95% CI 1.08-3.24) and fungal diversity (aOR = 3.00, 95% CI 1.55-5.79) were independently associated with LRTI risk among under-five children.

CONCLUSIONS

This study suggests an increased risk of LRTI when children under the age of five years are exposed to high levels of indoor microbial aerosols.

Overcrowding and Hazardous Dwelling Condition Characteristics: A Systematic Search and Scoping Review of Relevance for Health

Crowding in dwellings is an important public health issue. We hypothesize that overcrowding may cause indirect health effects by adversely affecting the dwelling itself, for example, by increasing dampness leading to mold. We therefore performed a systematic search and a scoping review on overcrowding leading to dwelling condition characteristics of relevance for health. A literature search was performed using the PubMed and Scopus databases up to 5 March 2021. The search yielded 100 records with relevant information. We found that overcrowding is defined in numerous ways and often address "socially deprived" populations. Six studies report associations of overcrowding with at least one dwelling condition characteristic, namely lead, cadmium, microorganism distribution, dust mite and cockroach allergens in dust, cockroach infestation, peeling paint, and mold. One of the studies reports associations between several characteristics, e.g., association of mold with cleanliness and rodent infestation, and points out the common use of pesticides. Additional characteristics were extracted from the remaining 94 records, without data on statistical associations with overcrowding. Our review suggests that multiple potentially hazardous dwelling condition characteristics often coincide in overcrowded dwellings. The epidemiological attribution of health effects to any characteristic is therefore difficult. Causal relationships are even more difficult to establish, as overcrowding is also associated with a range of social and other circumstances that may affect health. The complexity should be considered by scientists and practitioners dealing with overcrowding in dwellings.

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.

Predisposing factors to acquisition of acute respiratory tract infections in the community: a systematic review and meta-analysis

Background

Preventing respiratory tract infections (RTIs) could have profound effects on quality of life, primary care workload, antibiotic prescribing and stewardship. We aimed to identify factors that increase and decrease RTI acquisition within Organisation for Economic Cooperation and Development (OECD) member countries.

Methods

Systematic search of Medline, Embase, Cochrane and ISI Web of Knowledge for studies conducted up to July 2020 reporting predisposing factors for community RTI acquisition. Pooled odds ratios were calculated using a random-effects model.

Results

23 studies investigated risk factors associated with community-acquired pneumonia (n = 15); any RTI (n = 4); influenza like illness (n = 2); and lower RTI (n = 2). Demographic, lifestyle and social factors were: underweight BMI (pooled odds ratio (OR_p 2.14, 95% CI 1.58 to 2.70, p = 0.97); male sex (OR_p 1.30, 95% CI 1.27 to 1.33, p = 0.66); contact with pets (OR_p 1.35, 95% CI 1.16 to 1.54, p = 0.72); contact with children (OR_p 1.35, 95% CI 1.15 to 1.56, p = 0.05); and ex-smoking status (OR_p 1.57, 95% CI 1.26 to 1.88, p = 0.76). Health-related factors were: chronic liver condition (OR_p 1.30, 95% CI 1.09 to 1.50, p = 0.34); chronic renal condition (OR_p 1.47, 95% CI 1.09 to 1.85, p = 0.14); and any hospitalisation in previous five years (OR_p 1.64, 95% CI 1.46 to 1.82, p = 0.66).

Conclusions

We identified several modifiable risk factors associated with increased likelihood of acquiring RTIs in the community, including low BMI, contact with children and pets. Modification of risk factors and increased awareness of vulnerable groups could reduce morbidity, mortality and antibiotic use associated with RTIs.

PROSPERO registration

CRD42019134176.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12879-021-06954-3.

Particulate matter exposure predicts residence in high-risk areas for community acquired pneumonia among hospitalized children

Particulate matter exposure is a risk factor for lower respiratory tract infection in children. Here, we investigated the geospatial patterns of community-acquired pneumonia and the impact of PM_2.5 (particulate matter with an aerodynamic diameter ≤2.5 µm) on geospatial variability of pneumonia in children. We performed a retrospective analysis of prospectively collected population-based surveillance study data of community-acquired pneumonia hospitalizations among children <18 years residing in the Memphis metropolitan area, who were enrolled in the Centers for Disease Control and Prevention sponsored Etiology of Pneumonia in the Community (EPIC) study from January 2010 to June 2012. The outcome measure, residence in high- and low-risk areas for community-acquired pneumonia, was determined by calculating pneumonia incidence rates and performing cluster analysis to identify areas with higher/lower than expected rates of community-acquired pneumonia for the population at risk. High PM_2.5 was defined as exposure to PM_2.5 concentrations greater than the mean value (>10.75 μg/m³), and low PM_2.5 is defined as exposure to PM_2.5 concentrations less than or equal to the mean value (≤10.75 μg/m³). We also assessed the effects of age, sex, race/ethnicity, history of wheezing, insurance type, tobacco smoke exposure, bacterial etiology, and viral etiology of infection. Of 810 (96.1%) subjects with radiographic community-acquired pneumonia, who resided in the Memphis metropolitan area and had addresses which were successfully geocoded (Supplementary Figure F2), 220 (27.2%) patients were identified to be from high- (n = 126) or low-risk (n = 94) community-acquired pneumonia areas. Community-acquired pneumonia in Memphis metropolitan area had a non-homogenous geospatial pattern. PM_2.5 was associated with residence in high-risk areas for community-acquired pneumonia. In addition, children with private insurance and bacterial, as opposed to viral, etiology of infection had a decreased risk of residence in a high-risk area for community-acquired pneumonia. The results from this paper suggest that environmental exposures as well as social risk factors are associated with childhood pneumonia.

Environmental burden of disease from unsafe and substandard housing, New Zealand, 2010-2017

Objective

To assess the burden of disease related to unsafe and substandard housing conditions in New Zealand from 2010 to 2017.

Methods

We focused on substandard housing conditions most relevant for New Zealand homes: crowding, cold, damp or mould, and injury hazards linked to falls. We estimated the population attributable fraction using existing estimates of the population exposed and exposure–response relationships of health disorders associated with each housing condition. We used government hospitalization data, no-fault accident insurance claims and mortality data to estimate the annual disease burden from the most severe cases, as well as the resulting costs to the public sector in New Zealand dollars (NZ$). Using value of a statistical life measures, we estimated the indirect cost of deaths.

Findings

We estimated that illnesses attributable to household crowding accounted for 806 nights in hospital annually; cold homes for 1834 hospital nights; and dampness and mould for 36 649 hospital nights. Home injury hazards resulted in 115 555 annual accident claims. We estimated that direct public sector costs attributable to these housing conditions were approximately NZ$ 141 million (100 million United States dollars, US$) annually. We also estimated a total of 229 deaths annually attributable to adverse housing and the costs to society from these deaths at around NZ$ 1 billion (US$ 715 million).

Conclusion

Of the conditions assessed in this study, damp and mouldy housing accounted for a substantial proportion of the burden of disease in New Zealand. Improving people’s living conditions could substantially reduce total hospitalization costs and potentially improve quality of life.

Consensus Document on Community-Acquired Pneumonia in Children. SENP-SEPAR-SEIP

Community-acquired pneumonia (CAP) is a prevalent disease among children and is frequently associated with both diagnostic and therapeutic uncertainties. Consensus has been reached between SEPAR, SENP and SEIP, and their conclusions are as follows.

Risk Factors for Severe Pneumonia According to WHO 2005 Criteria Definition Among Children <5 Years of Age in Thai Binh, Vietnam: A Case-Control Study

Vietnam is one of the 15 countries where the prevalence of child pneumonia is highest. It is a major cause of admission in pediatric hospitals. However, little is known on the burden of severe pneumonia and their risk factors in children <5 years of age in Vietnam. A case–control study was conducted among children aged 2–59 months presenting with pneumonia at the Pediatric Provincial Hospital of Thai Binh. Cases were children with severe pneumonia while controls included those with non-severe pneumonia as defined by the World Health Organization (WHO) classification of 2005. Eighty-three cases and 83 controls were included. Sex ratio was 2.19. Children with severe pneumonia were significantly less likely to receive antibiotics preadmission compared to children with non-severe pneumonia [odds ratio (OR) = 0.16, 95% confidence interval (CI) = 0.06–0.42]. The main risk factors of severe pneumonia were a lack of immunization (OR = 4.77, 95% CI = 1.80–12.65), an exposure to cigarette smoke (OR = 3.87, 95% CI = 1.62–9.23), and having a mother with a low level of education. Children with severe pneumonia were 25 times more likely to present with associated measles with p < 0.0001 and five times more likely to present with diarrhea than children with non-severe pneumonia (p < 0.0001). Improving immunization coverage, educating parents about the risks of passive smoking and the recognition of respiratory distress signs, and facilitating early antibiotic access for infants with acute pulmonary disease should reduce the burden of such illnesses. To implement a national, multicenter study about pneumonia in children, more precise inclusion criteria should be chosen, including radiological and/or biological assessment.

Indoor microbiome and risk of lower respiratory tract infections among children under-five years: A meta-analysis

We investigated whether exposure to microbiome within the indoor environment is associated with risk of lower respiratory tract infections (LRTI) among children under 5 years of age. Electronic scientific repositories; PubMed, Scopus, Web of Science, GreenFILE, EMBASE, and Cochrane library were searched and screened through July 2019 for published reports for inclusion in the meta-analysis. Studies were eligible for inclusion if they reported an adjusted measure of risk for LRTI associated with IM exposure, including the relative risk (RR) or odds ratio (OR) and confidence interval (CI). The pooled OR was computed using the inverse of variance method for weighting. Sensitivity analysis was used to evaluate the effect of individual studies, while heterogeneity was evaluated by I² statistics using RevMan 5.3. Seven studies were eligible for inclusion in our meta-analysis. Exposure to a higher concentration of IM was associated with an increased risk of LRTI [OR:1.20 (1.11, 1.33), P < .0001]. The risk was stronger with exposure to total fungal concentration [OR:1.27 (1.13, 1.44), P < .0001] than visible molds [OR:1.20 (1.07, 1.34, P = .001]. Under-five children exposed to higher IM concentration are likely at increased risk of LRTI. Interventions addressing IM exposure should be considered in the management of LRTI among under-five children.

Pneumonia among under-five children in Alexandria, Egypt: a case-control study

Background

Pneumonia among under-five children constitutes a major public health concern. Studies examining risk factors for pneumonia in Egypt are limited.

Aim

To identify risk factors of pneumonia among under-five children in Alexandria, Egypt.

Methods

An observational case-control study was conducted over a 5-month period (September 2017–January 2018) in three main pediatric hospitals in Alexandria. A predesigned questionnaire was used to interview 660 mothers of under-five children (330 pneumonia cases and 330 control). The questionnaire included potential risk factors for pneumonia which were categorized into child-related factors, socio-demographic factors, and environmental factors.

Results

The mean age of the children was 23.14 ± 18.61 months with a range of 1–59 months. Nearly two-thirds (58.5%) were boys. Nine factors were found to be independently associated with pneumonia: age ≤ 12 months (OR = 1.925; 95% CI, 1.356–2.733; P < 0.001), male gender (OR = 1.646; 95% CI, 1.162–2.332; P = 0.005), birth order ≥ 4 (OR = 2.154; 95% CI, 1.282–3.617; P = 0.004), low birth weight (OR = 2.562; 95% CI, 1.718–3.821; P < 0.001), prematurity (OR = 2.019; 95% CI, 1.154–3.531; P = 0.014), place of delivery either at home (OR = 5.669; 95% CI, 1.063–30.237; P = 0.042) or at a public hospital (OR = 1.616; 95% CI, 1.131–2.310; P = 0.008), presence of concomitant illness (OR = 1.902; 95% CI, 1.043–3.469; P = 0.036), poor home aeration (OR = 3.586; 95% CI, 1.971–6.522; P < 0.001), and exposure to outdoor air pollution (OR = 2.403; 95% CI, 1.417–4.076; P = 0.001).

Conclusion

Several risk factors were significantly related to pneumonia among under-five children. Identifying such factors is important for developing interventions to reduce pneumonia burden among under-five in Egypt.

CLINICAL PROFILE OF CHILDREN WITH AND WITHOUT COMORBIDITIES HOSPITALIZED WITH COMMUNITY-ACQUIRED PNEUMONIA

Objective:

To describe the clinical profile of children and adolescents hospitalized with community-acquired pneumonia (CAP). They were divided into two groups: those with and those without comorbidities.

Methods:

An observational, cross-sectional, descriptive study with prospective data collection, was carried out in a cohort of patients aged zero to 11, who were hospitalized with a clinical and radiological diagnosis of community-acquired pneumonia, from January 2010 to January 2012. As an exploratory study, the two groups were compared through logistic regression for possible risk factors associated with community-acquired pneumonia. Relative risk (RR) was used with a 95% confidence interval (95%CI). The process of selection for independent variables was stepwise forward, with a significance level of 5%.

Results:

There were 121 cases of community-acquired pneumonia evaluated, and 47.9% had comorbidities. In the bivariate analysis, patients with comorbidities demonstrated higher chances for: age >60 months (p=0.005), malnutrition (p=0.002), previous use of antibiotics (p=0.008) and previous hospitalization for community-acquired pneumonia in the last 24 months (p=0.004). In the multivariate analysis, these variables were independent predictors of community-acquired pneumonia in patients with the comorbidities: age >60 months (p=0.002; RR=5.39; 95%CI 1.89-15.40); malnutrition (p=0.008; RR=1.75; 95%CI 1.75-44.60); previous use of antibiotics (p=0.0013; RR=3.03; 95%CI 1.27-7.20); and previous hospitalization for community-acquired pneumonia (p=0.035; RR=2.91; 95%CI 1.08-7.90).

Conclusions:

Most patients with community-acquired pneumonia and comorbidities were aged >60 months, were malnourished, had used antibiotics and had been hospitalized for community-acquired pneumonia. Comorbidities were associated with a higher chance of malnutrition and hospitalizations for community-acquired pneumonia in an older age group, compared to children without comorbidities. Knowledge of this clinical profile may contribute to better assist pediatric patients with community-acquired pneumonia hospitalized in referral centers.

Risk Factors for Acute Rheumatic Fever: Literature Review and Protocol for a Case-Control Study in New Zealand

Acute rheumatic fever (ARF) and its sequela, rheumatic heart disease (RHD), have largely disappeared from high-income countries. However, in New Zealand (NZ), rates remain unacceptably high in indigenous Māori and Pacific populations. The goal of this study is to identify potentially modifiable risk factors for ARF to support effective disease prevention policies and programmes. A case-control design is used. Cases are those meeting the standard NZ case-definition for ARF, recruited within four weeks of hospitalisation for a first episode of ARF, aged less than 20 years, and residing in the North Island of NZ. This study aims to recruit at least 120 cases and 360 controls matched by age, ethnicity, gender, deprivation, district, and time period. For data collection, a comprehensive pre-tested questionnaire focussed on exposures during the four weeks prior to illness or interview will be used. Linked data include previous hospitalisations, dental records, and school characteristics. Specimen collection includes a throat swab (Group A Streptococcus), a nasal swab (Staphylococcus aureus), blood (vitamin D, ferritin, DNA for genetic testing, immune-profiling), and head hair (nicotine). A major strength of this study is its comprehensive focus covering organism, host and environmental factors. Having closely matched controls enables the examination of a wide range of specific environmental risk factors.

Infant Food Security in New Zealand: A Multidimensional Index Developed from Cohort Data

Food security (FS) during infancy is associated with lifelong outcomes. New Zealand is a developed economy that reports poor childhood nutrition-related health statistics, particularly among minority children, yet has no measure of FS applicable to infancy. The objective was to develop an FS index for New Zealand infants and examine its association with demographic covariates and health outcomes. Within a large (n = 6853) nationally representative cohort, variables describing infant food consumption, breastfeeding, and maternal food-related coping methods were collected from mothers during late infancy. An FS index was derived using confirmatory factor analysis. Associations were assessed by logistic regressions and described using odds ratios (OR) and ≥95% confidence intervals (CI). Fifteen percent of the cohort was highly FS, 43% tenuously food insecure (FIS), and 16% highly food insecure (FIS). Infants from minority ethnic groups had lower odds of being food secure, as did those born to the youngest mothers, mothers who smoked, or those who lived in low-income households. FIS infants had higher odds of morbidity. Interventions to improve infant FS should focus on improving dietary quality, and should give particular consideration to minority infants. We identified that FIS shows wide ethnic and socioeconomic inequity, and is associated with poorer health. The most important driving factors of FIS included poor quality weaning diets, as well as poverty and its proxies. Any interventions to improve infant FS should focus on increasing fruit and vegetable consumption to recommended intake levels, and should give particular consideration to minority infants.

Hospitalization Rate and Population-based Incidence of Hospitalization for Community-acquired Pneumonia Among Children in Suzhou, China

BACKGROUND

Data on hospitalization burden of community-acquired pneumonia (CAP) in children are very limited in China. This study aimed to estimate the hospitalization rate (HR) and population-based incidence of hospitalization of CAP for children <15 years of age in Suzhou, China.

METHODS

This was a retrospective study of children hospitalized in Soochow University Affiliated Children's Hospital from January 2010 to December 2014. Children who were residents of downtown Suzhou, 29 days to <15 years of age, with discharge diagnosis codes (International Classification of Diseases, 10th revision) including J09-J18 and J20-J22 were included. All-cause clinical community-acquired pneumonia (CCAP) and radiographically confirmed pneumonia (RCAP) were identified based on individual medical chart review. The HR and population-based cumulative incidence of hospitalization (HI) were calculated.

RESULTS

Among 184,734 children <15 years of age admitted to Soochow University Affiliated Children's Hospital during the study period, 31,302 children were identified as having CCAP and 24,218 (77.4%) children confirmed as having RCAP. CCAP hospitalization occurred year round and peaked during winter and early spring. The overall HRs for CCAP and RCAP were 189.0 [95% confidence interval (CI): 187.1-190.9] and 146.2 (95% CI: 144-148) per 1000 hospitalizations, respectively, and the HIs per 100,000 children annually were CCAP, 3235.8 (95% CI: 3207.3-3264.2) and RCAP, 2503.5 (95% CI: 2478.3-2528.6). For children <5 years of age, the HR for CCAP was 248.4 (95% CI: 245.9-250.9) and RCAP was 194.0 (95% CI: 191.4-196.3) per 1000 hospitalizations; the HI for CCAP was 6956.2 (95% CI: 6892.8-7019.6) and 5431.9 (95% CI: 5375.4-5488.4) per 100,000 children for RCAP. The highest HR and HI were observed in children 29 days to <6 months of age: HR for CCAP was 407.4 (95% CI: 400.9-413.9) per 1000 hospitalizations and HI for CCAP was 11,203.7 (95% CI: 11,026.8-11,380.6) per 100,000 children annually.

CONCLUSIONS

There is a considerable burden of CAP among children <15 years of age in Suzhou, particularly among children 29 days to <6 months of age and during winter and early spring. These data provide valuable information to monitor CAP trends over time in children of Suzhou, China.

Residential risk factors for childhood pneumonia: A cross-sectional study in eight cities of China

BACKGROUND

Children's pneumonia is a heavy health burden. Few studies have been carried out on residential risk factors for pneumonia in children. Potential risks associated with dwelling characteristics are still unknown.

METHODS

A cross-sectional study was conducted among children in 8 cities in China during 2010-2011 and 41,176 valid data on children aged 3-8 years old were used in this analysis. To obtain the lifetime-ever incidence of pneumonia in children and identify associations between pneumonia and residential risk factors, chi-square analysis and logistic regression methods were employed. Adjusted odds ratios were used as measures of effect with a 95% confidence interval. Confounding variables in the regression model include children's gender, birthweight, breastfeeding duration, parental smoking and family history of atopy.

RESULTS

The average lifetime-ever incidence of childhood pneumonia was 32.3%. Urban children (33.6%) had more pneumonia than suburban (29.9%) and rural children (24.9%). More residential risk factors were found in urban-dwellings. Boys, low birthweight (<2500 g), breastfeeding duration <6 months, family allergic history, and exposure to parental smoking were found to be associated with higher pneumonia lifetime-ever incidences. Various indicators of dampness, including visible mold spots, damp stains, water damage, water condensation, damp clothing or bedding and mold odor, were also positively associated with pneumonia. Pneumonia incidence increased as the number of dampness indicators increased. Both natural gas and solid cooking fuels were positively associated with pneumonia compared with electricity. Compared with cement, construction materials including synthetic fiber, laminated wood, real wood, paint, emulsion paint and wall paper were positively associated with pneumonia. Daily living habits such as putting bedding to sunshine frequently and cleaning the child's bedroom every day could be effective preventive strategies. A dose-response relationship between the number of residential risk factors and pneumonia was observed when the risk factors number ranged from 7 to 11. Residences with more risk factors had higher lifetime-ever pneumonia odds ratios.

CONCLUSIONS

Indoor environmental factors including dampness, use of solid fuels or natural gas for cooking and use of new construction materials are risk factors for childhood pneumonia. This study gives evidence for the importance of home environment exposures in the occurrence of childhood pneumonia. Actions against the residential risk factors described in this study may help to prevent pneumonia in children.

Should Controls With Respiratory Symptoms Be Excluded From Case-Control Studies of Pneumonia Etiology? Reflections From the PERCH Study

Many pneumonia etiology case-control studies exclude controls with respiratory illness from enrollment or analyses. Herein we argue that selecting controls regardless of respiratory symptoms provides the least biased estimates of pneumonia etiology. We review 3 reasons investigators may choose to exclude controls with respiratory symptoms in light of epidemiologic principles of control selection and present data from the Pneumonia Etiology Research for Child Health (PERCH) study where relevant to assess their validity. We conclude that exclusion of controls with respiratory symptoms will result in biased estimates of etiology. Randomly selected community controls, with or without respiratory symptoms, as long as they do not meet the criteria for case-defining pneumonia, are most representative of the general population from which cases arose and the least subject to selection bias.

Community-level characteristics and environmental factors of child respiratory illnesses in Southern Arizona

BACKGROUND

Lower respiratory illnesses (LRIs) and asthma are common diseases in children <5 years of age. Few studies have investigated the relationships between multiple, home-based social and environmental risk factors and asthma and LRIs in children. Of those that have, none have focused exclusively on children <5 years of age, who are more physiologically vulnerable and spend more time at home compared to older children. Further, no studies have done so at the community level.

METHODS

We modeled relationships between emergency department visits and hospitalization rates for asthma and LRIs for children <5 years and geographic risk factors, including socio-economic and housing characteristics, ambient air pollution levels, and population density in Maricopa and Pima Counties, Arizona, from 2005 to 2009. We used a generalized linear model with a negative binomial observation distribution and an offset for the population of very young children in each tract. To reduce multicollinearity among predictors, socio-economic characteristics, and ambient air pollutant levels were combined into unit-less indices using the principal components analysis (PCA). Housing characteristics variables did not exhibit moderate-to-high correlations and thus were not included in PCA. Spatial autocorrelation among regression model residuals was assessed with the Global Moran's I test.

RESULTS

Following the regression analyses, almost all predictors were significantly related to at least one disease outcome. Lower socio-economic status (SES) and reduced population density were associated with asthma hospitalization rates and both LRI outcomes (p values <0.001). After adjusting for differences between counties, Pima County residence was associated with lower asthma and LRI hospitalization rates. No spatial autocorrelation was found among multiple regression model residuals (p values >0.05).

CONCLUSIONS

Our study revealed complex, multi-factorial associations between predictors and outcomes. Findings indicate that many rural areas with lower SES have distinct factors for childhood respiratory diseases that require further investigation. County-wide differences in maternal characteristics or agricultural land uses (not tested here) may also play a role in Pima County residence protecting against hospitalizations, when compared to Maricopa County. By better understanding this and other relationships, more focused public health interventions at the community level could be developed to reduce and better control these diseases in children <5 years, who are more physiologically vulnerable.

Community-acquired pneumonia in the post 13-valent pneumococcal conjugate vaccine era

PURPOSE OF REVIEW

This review covers the outpatient management of pediatric community-acquired pneumonia (CAP), discussing the changing microbiology of CAP since the introduction of the 13-valent pneumococcal conjugate vaccine in 2010, and providing an overview of national guideline recommendations for diagnostic evaluation and treatment.

RECENT FINDINGS

Rates of invasive pneumococcal disease and pneumococcal antibiotic resistance have plummeted since widespread 13-valent pneumococcal conjugate vaccine immunization. Viruses remain the most common cause of CAP in young children; children over age 5 years have increased rates of Mycoplasma pneumoniae. A recent national guideline offers recommendations for office-based diagnostic evaluation and treatment of pediatric CAP.

SUMMARY

This review offers a discussion of the above findings with practical recommendations for the office-based practitioner in the evaluation and treatment of an infant (>3 months) or child with suspected CAP.

Risk factors for community-acquired pneumonia in children under five years of age in the post-pneumococcal conjugate vaccine era in Brazil: a case control study

BACKGROUND

Pneumonia plays an important role in children's morbidity and mortality. In Brazil, epidemiological and social changes occurred concomitantly with the universal introduction of the 10-valent pneumococcal conjugate vaccine. This study identified risk factors for pneumonia following the implementation of a pneumococcal vaccination program.

METHODS

A hospital-based, case-control study involving incident cases of pneumonia in children aged 1-59 months was conducted between October 2010 and September 2013 at a tertiary hospital in northeastern Brazil. The diagnosis of pneumonia was based on the World Health Organization (WHO) criteria. The control group consisted of children admitted to the day-hospital ward for elective surgery. Children with comorbidities were excluded. The risk factors for pneumonia that were investigated were among those classified by the WHO as definite, likely and possible. A multivariate analysis was performed including variables that were significant at p ≤ 0.25 in the bivariate analysis.

RESULTS

The study evaluated 407 children in the case group and 407 children in the control group. Household crowding (OR = 2.15; 95 % CI, 1,46-3,18) and not having been vaccinated against the influenza virus (OR = 3.59; 95 % CI, 2,62-4.91) were the only factors found to increase the likelihood of pneumonia. Male gender constituted a protective factor (OR = 0.53; 95 % CI, 0,39-0,72).

CONCLUSION

Changes on risk factors for pneumonia were most likely associated with the expansion of the vaccination program and social improvements; however, these improvements were insufficient to overcome inequalities, given that household crowding remained a significant risk factor. The protection provided by the influenza vaccine must be evaluated new etiological studies. Furthermore, additional risk factors should be investigated.

Factors Associated with Age at Breastfeeding Cessation in Amazonian Infants: Applying a Proximal-Distal Framework

Introduction Breastfeeding is an important determinant of child survival and normal growth and development, but breastfeeding prevalence is generally low in Brazil. Factors associated with infant feeding practices there are not well understood. This paper examines factors associated with breastfeeding cessation in a township in the western Brazilian Amazon. Methods A cross-sectional, population-based study was conducted among children younger than 25 months and collected information on maternal and child characteristics. Survival analysis based on a proximal-distal framework examined the association between breastfeeding duration and socioeconomic and maternal/child biological factors. Results The median breastfeeding duration among 101 children who were no longer breastfeeding was 120 days. Almost two-thirds (63 %) of these children stopped breastfeeding before 6 months of age. In the larger sample of 209 children, 74.6 % had previously been bottle-fed. Considering the full proximal-distal model, a child who had ever been bottle-fed was expected to cease breastfeeding about 88 % sooner than one who was never bottle-fed (p < 0.001). Children in the second-poorest wealth quartile stopped breastfeeding sooner than children in the poorest quartile (p < 0.05). Discussion Breastfeeding cessation in the study area occurred much earlier than the recommended 2 years of age. Factors associated with ending breastfeeding early included ever-use of a bottle, having a single mother, and belonging to the second-poorest wealth quartile. Further research is needed to better understand these factors and other barriers women face to continuing breastfeeding.

Collaborating with a social housing provider supports a large cohort study of the health effects of housing conditions

Background

Despite the importance of adequate, un-crowded housing as a prerequisite for good health, few large cohort studies have explored the health effects of housing conditions. The Social Housing Outcomes Worth (SHOW) Study was established to assess the relationship between housing conditions and health, particularly between household crowding and infectious diseases. This paper reports on the methods and feasibility of using a large administrative housing database for epidemiological research and the characteristics of the social housing population.

Methods

This prospective open cohort study was established in 2003 in collaboration with Housing New Zealand Corporation which provides housing for approximately 5 % of the population. The Study measures health outcomes using linked anonymised hospitalisation and mortality records provided by the New Zealand Ministry of Health.

Results

It was possible to match the majority (96 %) of applicant and tenant household members with their National Health Index (NHI) number allowing linkage to anonymised coded data on their hospitalisations and mortality. By December 2011, the study population consisted of 11,196 applicants and 196,612 tenants. Half were less than 21 years of age. About two-thirds identified as Māori or Pacific ethnicity. Household incomes were low. Of tenant households, 44 % containing one or more smokers compared with 33 % for New Zealand as a whole. Exposure to household crowding, as measured by a deficit of one or more bedrooms, was common for applicants (52 %) and tenants (38 %) compared with New Zealanders as whole (10 %).

Conclusions

This project has shown that an administrative housing database can be used to form a large cohort population and successfully link cohort members to their health records in a way that meets confidentiality and ethical requirements. This study also confirms that social housing tenants are a highly deprived population with relatively low incomes and high levels of exposure to household crowding and environmental tobacco smoke.

Clinical and epidemiological characteristics of severe community-acquired pneumonia in children after introduction of the 10-valent pneumococcal vaccine

Background

Pneumonia is an important cause of morbimortality in Brazil, despite the extensive vaccination coverage and the socioeconomic improvement in the past years.

Objective

To describe the epidemiological and clinical characteristics of severe community-acquired pneumonia in children after the introduction of the 10-valent pneumococcal conjugate vaccine (PCV10).

Methods

A prospective study included children <5 years old hospitalized for pneumonia between October 2010 and September 2013 in a tertiary hospital. Newborns and children with comorbidities were excluded. Pneumonia classification followed the clinical and radiological criteria established by World Health Organization (WHO). Clinical history, nutritional status, immunizations, diagnosis, disease course, and prognosis were analyzed.

Results

Among 452 children, almost 70% were <2 years, with no sex differences, and 10% had weight-for-age z score below than -2.0. Family income was up to one minimum wage in half the households, and 40% of mothers had completed high school. The suitability of both influenza and PCV10 vaccine schedules was ∼50%. The first medical care happened later than 72 hours after the onset of symptoms in 42% of cases. Pneumonia was classified as severe or very severe in 83.9% of patients and for 23% as complicated. Global mortality was 1.5%. Hypoxia, diagnosed in 51.5% of children, looked like a better prognosis predictor than the WHO classification.

Conclusion

New strategies for health care are necessary, such as the incorporation of peripheral saturometry as the "fifth signal", investment in vaccine coverage, and the adequacy of hospital infrastructure for assistance of severely affected patients.

Improvement methodology increases guideline recommended blood cultures in children with pneumonia

BACKGROUND AND OBJECTIVE

A national evidence-based guideline for the management of community-acquired pneumonia (CAP) in children recommends blood cultures for patients admitted with moderate to severe illness. Our primary aim was to increase ordering of blood cultures for children hospitalized with CAP from 53% to 90% in 6 months. The secondary aim was to evaluate the effect of obtaining blood cultures on length of stay (LOS).

METHODS

At a tertiary children's hospital, interventions to increase blood cultures focused on 3 key drivers and were tested separately in the emergency department and inpatient units by using multiple plan-do-study-act cycles. The impact of the interventions was tracked over time on run charts. The association of ordering blood cultures and LOS was estimated by using linear regression models.

RESULTS

Within 6 months, the percentage of patients admitted with CAP who had blood cultures ordered increased from 53% to 100%. This change has been sustained for 12 months. Overall, 239 (79%) of the 303 included patients had a blood culture ordered; of these, 6 (2.5%) were positive. Patients who had a blood culture did not have an increased LOS compared with those without a blood culture.

CONCLUSIONS

Quality improvement methods were used to increase adherence to evidence-based national guidelines for performing blood cultures on children hospitalized with CAP; LOS did not increase. These results support obtaining blood cultures on all patients admitted with CAP without negative effects on LOS in a setting with a reliably low false-positive blood culture rate.

The impact of primary care on emergency department presentation and hospital admission with pneumonia: a case-control study of preschool-aged children

BACKGROUND

In children, community-acquired pneumonia is a frequent cause of emergency department (ED) presentation and hospital admission. Quality primary care may prevent some of these hospital visits.

AIMS

The aim of this study was to identify primary care factors associated with ED presentation and hospital admission of preschool-aged children with community-acquired pneumonia.

METHODS

A case-control study was conducted by enrolling three groups: children presenting to the ED with pneumonia and admitted (n = 326), or discharged home (n = 179), and well-neighbourhood controls (n = 351). Interviews with parents and primary care staff were conducted and health record review was performed. The association of primary care factors with ED presentation and hospital admission, controlling for available confounding factors, was determined using logistic regression.

RESULTS

Children were more likely to present to the ED with pneumonia if they did not have a usual general practitioner (GP) (odds ratio (OR) = 2.50, 95% confidence interval (CI) = 1.67-3.70), their GP worked ⩽ 20 h/week (OR = 1.86, 95% CI = 1.10-3.13) or their GP practice lacked an immunisation recall system (OR = 5.44, 95% CI = 2.26-13.09). Lower parent ratings for continuity (OR=1.63, 95% CI = 1.01-2.62), communication (OR = 2.01, 95% CI = 1.29-3.14) and overall satisfaction (OR = 2.16, 95% CI = 1.34-3.47) increased the likelihood of ED presentation. Children were more likely to be admitted when antibiotics were prescribed in primary care (OR = 2.50, 95% CI = 1.43-4.55). Hospital admission was less likely if children did not have a usual GP (OR = 0.22, 95% CI = 0.11-0.40) or self-referred to the ED (OR = 0.48, 95% CI = 0.26-0.89).

CONCLUSIONS

Accessible and continuous primary care is associated with a decreased likelihood of preschool-aged children with pneumonia presenting to the ED and an increased likelihood of hospital admission, implying more appropriate referral. Lower parental satisfaction is associated with an increased likelihood of ED presentation.

Implementing hospital-based surveillance for severe acute respiratory infections caused by influenza and other respiratory pathogens in New Zealand

BACKGROUND

Recent experience with pandemic influenza A(H1N1)pdm09 highlighted the importance of global surveillance for severe respiratory disease to support pandemic preparedness and seasonal influenza control. Improved surveillance in the southern hemisphere is needed to provide critical data on influenza epidemiology, disease burden, circulating strains and effectiveness of influenza prevention and control measures. Hospital-based surveillance for severe acute respiratory infection (SARI) cases was established in New Zealand on 30 April 2012. The aims were to measure incidence, prevalence, risk factors, clinical spectrum and outcomes for SARI and associated influenza and other respiratory pathogen cases as well as to understand influenza contribution to patients not meeting SARI case definition.

METHODS/DESIGN

All inpatients with suspected respiratory infections who were admitted overnight to the study hospitals were screened daily. If a patient met the World Health Organization's SARI case definition, a respiratory specimen was tested for influenza and other respiratory pathogens. A case report form captured demographics, history of presenting illness, co-morbidities, disease course and outcome and risk factors. These data were supplemented from electronic clinical records and other linked data sources.

DISCUSSION

Hospital-based SARI surveillance has been implemented and is fully functioning in New Zealand. Active, prospective, continuous, hospital-based SARI surveillance is useful in supporting pandemic preparedness for emerging influenza A(H7N9) virus infections and seasonal influenza prevention and control.

Impact of the socioeconomic status on the severity and outcome of community-acquired pneumonia among Egyptian children: a cohort study

BACKGROUND

Community-acquired pneumonia (CAP) is one of the five leading causes of death among children in developing countries, accounting for approximately three million deaths per year. Identification of the modifiable risk factors of CAP may help to reduce the burden of this disease. In this study, the impact of the socioeconomic status (SES) on the severity and outcome of CAP among Egyptian children was studied.

METHODS

This was a prospective longitudinal cohort study which included 1,470 children diagnosed with CAP, aged two to 15 years (median age 5.4 years). The diagnosis of CAP was based on clinical and radiological findings. A structured questionnaire and the patients' medical records were used for the data collection. The subjects were divided into two groups: mild and severe CAP. Social and demographic variables were compared, and a multivariate logistic regression analysis was performed.

RESULTS

THE MULTIVARIATE ANALYSIS SHOWED THAT A LOW MATERNAL EDUCATION LEVEL (OR: 3.8; 95% CI: 2.12 -6.70; P = .0001), unavailability of adequate medical care (OR: 3.1; 95% CI: 1.99 -4.88; P = .0001), a low family income (OR: 2.2; 95% CI: 0.99 -4.78; P = .047), and parents' smoking habits (OR: 2.0; 95% CI: 1.15 -3.55; P = .014) were significant independent predictive risk factors for severe CAP among Egyptian children.

CONCLUSION

Public health measures against these socio-demographic risk factors should be identified as priorities in order to help reduce the disease burden of deaths from severe CAP among Egyptian children.

Respiratory health outcomes 1 year after admission with severe lower respiratory tract infection

Severe lower respiratory infection (LRI) is believed to be one precursor of protracted bacterial bronchitis, chronic moist cough (CMC), and chronic suppurative lung disease. The aim of this study was to determine and to describe the presence of respiratory morbidity in young children 1 year after being hospitalized with a severe LRI. Children aged less than 2 years admitted from August 1, 2007 to December 23, 2007 already enrolled in a prospective epidemiology study (n = 394) were included in this second study only if they had a diagnosis of severe bronchiolitis or of pneumonia with no co-morbidities (n = 237). Funding allowed 164 to be identified chronologically, 131 were able to be contacted, and 94 agreed to be assessed by a paediatrician 1 year post index admission. Demographic information, medical history and a respiratory questionnaire was recorded, examination, pulse oximetry, and chest X-ray (CXR) were performed. The predetermined primary endpoints were; (i) history of CMC for at least 3 months, (ii) the presence of moist cough and/or crackles on examination in clinic, and (iii) an abnormal CXR when seen at a time of stability. Each CXR was read by two pediatric radiologists blind to the individuals' current health. Results showed 30% had a history of CMC, 32% had a moist cough and/or crackles on examination in clinic, and in 62% of those with a CXR it was abnormal. Of the 81 children with a readable follow-up X-ray, 11% had all three abnormal outcomes, and 74% had one or more abnormal outcomes. Three children had developed bronchiectasis on HRCT. The majority of children with a hospital admission at <2 years of age for severe bronchiolitis or pneumonia continued to have respiratory morbidity 1 year later when seen at a time of stability, with a small number already having sustained significant lung disease.

Risk factors for severe acute lower respiratory infections in children: a systematic review and meta-analysis

AIM

To identify the risk factors in children under five years of age for severe acute lower respiratory infections (ALRI), which are the leading cause of child mortality.

METHODS

We performed a systematic review of published literature available in the public domain. We conducted a quality assessment of all eligible studies according to GRADE criteria and performed a meta-analysis to report the odds ratios for all risk factors identified in these studies.

RESULTS

We identified 36 studies that investigated 19 risk factors for severe ALRI. Of these, 7 risk factors were significantly associated with severe ALRI in a consistent manner across studies, with the following meta-analysis estimates of odds ratios (with 95% confidence intervals): low birth weight 3.18 (1.02-9.90), lack of exclusive breastfeeding 2.34 (1.42-3.88), crowding - more than 7 persons per household 1.96 (1.53-2.52), exposure to indoor air pollution 1.57 (1.06-2.31), incomplete immunization 1.83 (1.32-2.52), undernutrition - weight-for-age less than 2 standard deviations 4.47 (2.10-9.49), and HIV infection 4.15 (2.57-9.74).

CONCLUSION

This study highlights the role of the above seven risk factors in the development of severe pneumonia in under-five children. In addition, it emphasizes the need for further studies investigating other potential risk factors. Since these risk factors are potentially preventable, health policies targeted at reducing their prevalence provide a basis for decreasing the burden of childhood pneumonia.

Community-Acquired Pneumonia in the Conjugate Vaccine Era

Community-acquired pneumonia (CAP) remains one of the most common serious infections encountered among children worldwide. In this review, we highlight important literature and recent scientific discoveries that have contributed to our current understanding of pediatric CAP. We review the current epidemiology of childhood CAP in the developed world, appraise the state of diagnostic testing for etiology and prognosis, and discuss disease management and areas for future research in the context of recent national guidelines.