Acute respiratory tract infections in children. A three-year follow-up from birth

Ongoing strategies to improve the management of upper respiratory tract infections and reduce inappropriate antibiotic use particularly among lower and middle-income countries: findings and implications for the future

Introduction: Antibiotics are indispensable to maintaining human health; however, their overuse has resulted in resistant organisms, increasing morbidity, mortality and costs. Increasing antimicrobial resistance (AMR) is a major public health threat, resulting in multiple campaigns across countries to improve appropriate antimicrobial use. This includes addressing the overuse of antimicrobials for self-limiting infections, such as upper respiratory tract infections (URTIs), particularly in lower- and middle-income countries (LMICs) where there is the greatest inappropriate use and where antibiotic utilization has increased the most in recent years. Consequently, there is a need to document current practices and successful initiatives in LMICs to improve future antimicrobial use.Methodology: Documentation of current epidemiology and management of URTIs, particularly in LMICs, as well as campaigns to improve future antimicrobial use and their influence where known.Results: Much concern remains regarding the prescribing and dispensing of antibiotics for URTIs among LMICs. This includes considerable self-purchasing, up to 100% of pharmacies in some LMICs. However, multiple activities are now ongoing to improve future use. These incorporate educational initiatives among all key stakeholder groups, as well as legislation and other activities to reduce self-purchasing as part of National Action Plans (NAPs). Further activities are still needed however. These include increased physician and pharmacist education, starting in medical and pharmacy schools; greater monitoring of prescribing and dispensing practices, including the development of pertinent quality indicators; and targeted patient information and health education campaigns. It is recognized that such activities are more challenging in LMICs given more limited resources and a lack of healthcare professionals.Conclusion: Initiatives will grow across LMICs to reduce inappropriate prescribing and dispensing of antimicrobials for URTIs as part of NAPs and other activities, and these will be monitored.

Herring roe oil supplementation alters microglial cell gene expression and reduces peripheral inflammation after immune activation in a neonatal piglet model

Neonatal brain development can be disrupted by infection that results in microglial cell activation and neuroinflammation. Studies indicate that polyunsaturated fatty acids (PUFAs) and their metabolites can resolve inflammation. It is not known if dietary PUFA increases lipid metabolites in brain or reduces neuroinflammation in neonates. We hypothesized that dietary PUFAs might suppress neuroinflammation by inhibiting pro-inflammatory cytokine over-production and promoting inflammatory resolution in the periphery and brain. Piglets were obtained on postnatal day (PD) 2 and randomly assigned to herring roe oil (HRO) or control (CON) diet. HRO was included at 2 g/kg powdered diet. HRO increased DHA levels in occipital lobe and the DHA to arachidonic acid (ARA) ratio in hippocampal tissue. HRO decreased ARA metabolites in occipital lobe. HRO failed to attenuate microglial pro-inflammatory cytokine production ex vivo. HRO did not affect fever or circulating resolvin D1 levels. HRO decreased circulating neutrophils and liver inflammatory gene expression, but increased resolution marker gene expression in liver post LPS. HRO upregulated CXCL16, TGFBR1, and C1QA in microglial cells. HRO supplementation exerted beneficial effects on inflammation in the periphery, but further studies are needed to evaluate the specific effects of omega-3 supplementation on microglial cell physiology in the neonate.

Modulation of airway epithelial cell functions by Pidotimod: NF-kB cytoplasmatic expression and its nuclear translocation are associated with an increased TLR-2 expression

Background

Recurrent respiratory infections are one of the most important causes of morbidity in childhood. When immune functions are still largely immature, the airway epithelium plays a primary defensive role since, besides providing a physical barrier, it is also involved in the innate and the adaptive immune responses. A study was therefore designed to evaluate in vitro whether pidotimod, a synthetic dipeptide able to stimulate the inflammatory and immune effector cells, could activate bronchial epithelial cell functions involved in response to infections.

Methods

BEAS-2B cell line (human bronchial epithelial cells infected with a replication-defective Adenovirus 12-SV40 virus hybrid) were cultured in the presence of pidotimod, with or without tumor necrosis factor (TNF)-α or zymosan to assess: a) intercellular adhesion molecule (ICAM)-1 expression, by flow cytometry; b) toll-like receptor (TLR)-2 expression and production, by immunofluorescence flow cytometry and western blotting; d) interleukin (IL)-8 release, by enzyme-linked immunosorbent assay (ELISA); e) activated extracellular-signal-regulated kinase (ERK1/2) phosphorylation and nuclear factor-kappa B (NF-kB) activation, by western blotting.

Results

The constitutive expression of ICAM-1 and IL-8 release were significant up-regulated by TNF-α (ICAM-1) and by TNF-α and zymosan (IL-8), but not by pidotimod. In contrast, an increased TLR-2 expression was found after exposure to pidotimod 10 and 100 μg/ml (p < 0.05) and to the association pidotimod 100 μg/ml + TNF-α (p < 0.05). Western blot analysis substantiated that the constitutive TLR-2 expression was significantly increased after exposure to all the stimuli. Finally, while a remarkable inhibition of TNF-α -induced ERK1/2 phosphorylation was observed in the presence of pidotimod, both TNF-α and pidotimod were effective in inducing NF-kB protein expression in the cytoplasm and its nuclear translocation.

Conclusion

Through different effects on ERK1/2 and NF-kB, pidotimod was able to increase the expression of TLR-2 proteins, surface molecules involved in the initiation of the innate response to infectious stimuli. The lack of effect on ICAM-1 expression, the receptor for rhinovirus, and on IL-8 release, the potent chemotactic factor for neutrophils (that are already present in sites of infection), may represent protective functions. If confirmed in vivo, these activities may, at least in part, clarify the mechanism of action of this molecule at airway level.

The impact of dietary long-chain polyunsaturated fatty acids on respiratory illness in infants and children

Increasing evidence suggests that intake of long-chain polyunsaturated fatty acids (LCPUFA), especially omega-3 LCPUFA, improves respiratory health early in life. This review summarizes publications from 2009 through July 2012 that evaluated effects of fish, fish oil or LCPUFA intake during pregnancy, lactation, and early postnatal years on allergic and infectious respiratory illnesses. Studies during pregnancy found inconsistent effects in offspring: two showed no effects and three showed protective effects of omega-3 LCPUFA on respiratory illnesses or atopic dermatitis. Two studies found that infants fed breast milk with higher omega-3 LCPUFA had reduced allergic manifestations. Earlier introduction of fish improved respiratory health or reduced allergy in four studies. Three randomized controlled trials showed that providing LCPUFA during infancy or childhood reduced allergy and/or respiratory illness while one found no effect. Potential explanations for the variability among studies and possible mechanisms of action for LCPUFA in allergy and respiratory disease are discussed.

Effectiveness of adenoidectomy in children with recurrent upper respiratory tract infections: open randomised controlled trial

OBJECTIVE

To assess the effectiveness of adenoidectomy in children with recurrent upper respiratory tract infections.

DESIGN

Open randomised controlled trial.

SETTING

11 general hospitals and two academic centres.

PARTICIPANTS

111 children aged 1-6 with recurrent upper respiratory tract infections selected for adenoidectomy.

INTERVENTION

A strategy of immediate adenoidectomy with or without myringotomy or a strategy of initial watchful waiting. Main outcome measure Primary outcome measure: number of upper respiratory tract infections per person year calculated from data obtained during the total follow-up (maximum 24 months).

SECONDARY OUTCOME MEASURES

days with upper respiratory tract infection per person year, middle ear complaints with fever in episodes and days, days with fever, prevalence of upper respiratory tract infections, and health related quality of life.

RESULTS

During the median follow-up of 24 months, there were 7.91 episodes of upper respiratory tract infections per person year in the adenoidectomy group and 7.84 in the watchful waiting group (difference in incidence rate 0.07, 95% confidence interval -0.70 to 0.85). No relevant differences were found for days of upper respiratory tract infections and middle ear complaints with fever in episodes and days, nor for health related quality of life. The prevalence of upper respiratory tract infections decreased over time in both groups. Children in the adenoidectomy group had significantly more days with fever than the children in the watchful waiting group. Two children had complications related to surgery.

CONCLUSION

In children selected for adenoidectomy for recurrent upper respiratory tract infections, a strategy of immediate surgery confers no clinical benefits over a strategy of initial watchful waiting. Trial registration Dutch Trial Register NTR968: ISRCTN03720485.

The impact of early nutrition on incidence of allergic manifestations and common respiratory illnesses in children

OBJECTIVE

To investigate the incidence of allergic and respiratory diseases through age 3 years in children fed docosahexaenoic acid (DHA)- and arachidonic acid (ARA)-supplemented formula during infancy.

STUDY DESIGN

Children who completed randomized, double-blind studies of DHA/ARA-supplemented (0.32%-0.36%/0.64%-0.72% of total fatty acids, respectively) versus nonsupplemented (control) formulas, fed during the first year of life, were eligible. Blinded study nurses reviewed medical charts for upper respiratory infection (URI), wheezing, asthma, bronchiolitis, bronchitis, allergic rhinitis, allergic conjunctivitis, otitis media, sinusitis, atopic dermatitis (AD), and urticaria.

RESULTS

From the 2 original cohorts, 89/179 children participated; 38/89 were fed DHA/ARA formula. The DHA/ARA group had significantly lower odds for developing URI (odds ratio [OR], 0.22; 95% confidence interval [CI], 0.08-0.58), wheezing/asthma (OR, 0.32; 95% CI, 0.11-0.97), wheezing/asthma/AD (OR, 0.25; 95% CI, 0.09-0.67), or any allergy (OR, 0.28; 95% CI, 0.10-0.72). The control group had significantly shorter time to first diagnosis of URI (P = .006), wheezing/asthma (P = .03), or any allergy (P = .006).

CONCLUSIONS

DHA/ARA supplementation was associated with delayed onset and reduced incidence of URIs and common allergic diseases up to 3 years of age.

Primary care management of respiratory tract infections in Dutch preschool children

OBJECTIVE

To determine age-specific antibiotic prescription and referral rates in preschool children diagnosed with acute respiratory tract infection (RTI) in primary care.

DESIGN

Retrospective cohort study.

SETTING

Research database of the Netherlands University Medical Center Utrecht Primary Care Network.

SUBJECTS

All children aged 0-5 years within the database were included, covering 1998 to 2002 (18,801 child-years).

MAIN OUTCOME MEASURES

Antibiotic prescription and referral rates were determined as percentage of children with at least one prescription or referral within a year, as total number of prescriptions per 1000 child-years, and as percentage of all RTI episodes.

RESULTS

Antibiotics, mostly beta-lactam (80%) and macrolides (16%), were prescribed in 35% of RTI episodes. Annually 13% of the children received at least one antibiotic following an RTI. Antibiotics were prescribed in more than half of episodes of LRTI, sinusitis, AOM, and acute tonsillitis, and in 12-15% of episodes of asthma exacerbation, acute laryngitis, influenza acute, and acute upper respiratory infection (including common cold and pharyngitis). Almost 98% of RTIs were managed in primary care. On average 1% of the children were referred to a paediatrician or ENT specialist following RTI per year, especially after AOM (59% of referrals). Compared with older children, those under two years of age were more often treated with antibiotics (relative risk [RR] 1.4, 95% CI 1.3-1.6) and referred (RR 2.3; 95% CI 1.8-3.0).

CONCLUSION

In the Netherlands most episodes of RTIs in preschool children were managed in primary care and this often involves prescription of antibiotics. Children younger than two years of age receive more often antibiotics for RTI and are also referred more, especially for AOM.

A randomized, double-blind, placebo-controlled noninferiority trial of amoxicillin for clinically diagnosed acute otitis media in children 6 months to 5 years of age

OBJECTIVES

Debate continues with respect to a "watch and wait" approach versus immediate antibiotic treatment for the initial treatment of acute otitis media. In this double-blind noninferiority trial, we compared clinical improvement rates at 14 days for children (6 months to 5 years of age) with acute otitis media who were randomly assigned to receive amoxicillin or placebo.

METHODS

We enrolled healthy children who presented to clinics or the emergency department with a new episode of acute otitis media during the fall and winter months in Ottawa (from December 1999 to the end of March 2002). The children were randomly assigned to receive amoxicillin (60 mg/kg daily) or placebo for 10 days. Telephone follow-up was performed on each of days 1, 2 and 3 and once between day 10 and day 14. The primary outcome was clinical resolution of symptoms, defined as absence of receipt of an antimicrobial (other than the amoxicillin in the treatment group) at any time during the 14-day period. Secondary outcomes were the presence of pain and fever and the activity level in the first 3 days, recurrence rates, and the presence of middle ear effusion at 1 and 3 months.

RESULTS

According to clinical scoring, 415 of the 512 children who could be evaluated had moderate disease. At 14 days 84.2% of the children receiving placebo and 92.8% of those receiving amoxicillin had clinical resolution of symptoms (absolute difference -8.6%, 95% confidence interval -14.4% to -3.0%). Children who received placebo had more pain and fever in the first 2 days. There were no statistical differences in adverse events between the 2 groups, nor were there any significant differences in recurrence rates or middle ear effusion at 1 and 3 months.

INTERPRETATION

Our results did not support the hypothesis that placebo was noninferior to amoxicillin (i.e., that the 14-day cure rates among children with clinically diagnosed acute otitis media would not be substantially worse in the placebo group than the treatment group). Nevertheless, delaying treatment was associated with resolution of clinical signs and symptoms in most of the children.

Viral etiology of frequently recurring respiratory tract infections in children

The viral etiology of frequently recurring respiratory tract infection (FRRI) in children aged <2 years was studied. Altogether, 329 children were followed from 2 to 24 months of age in the Finnish Otitis Media Cohort Study. Children with FRRI were defined as having > or =9 episodes of upper respiratory tract infection (URI) and/or > or =4 episodes of acute otitis media during follow-up. Nasopharyngeal aspirates, middle ear fluid specimens, and serum samples were analyzed for 8 common respiratory viruses. Of 1358 URI episodes, 642 (47%) occurred in the 78 children with FRRI. At least 1 virus was associated with 62% of these episodes, whereas the corresponding figure for children without FRRIs was 54%. The frequency of different viruses was similar in both groups, but the relative proportion of rhinovirus infections was slightly higher among children with FRRI. In conclusion, a specific viral etiology does not explain the excess of URI episodes in children with FRRI.

Epidemiology of documented viral respiratory infections and acute otitis media in a cohort of children followed from two to twenty-four months of age

BACKGROUND

Viral upper respiratory infections (URIs) are considered major risk factors for acute otitis media (AOM) in young children. We studied the epidemiology and relative roles of different viruses in respiratory infections in a cohort of 329 Finnish children followed from 2 months to 2 years of age.

METHODS

A nasopharyngeal aspirate (NPA) was collected whenever the child had signs and/or symptoms of URI and tested for the presence of common respiratory virus antigens or infectivity/nucleic acid (only rhinoviruses). Possible repeated detections of a given virus during a 30-day period were considered to represent a single designated virus-specific episode. AOM and URI episodes were defined in a similar way.

RESULTS

At least one virus was detected in 837 (41.7%) of the 2005 NPA specimens examined. Rates of URI and virus-specific episodes showed expected seasonal variation with major peak occurrences coinciding with or preceding those of AOM. The proportions of rhinoviruses, respiratory syncytial (RS) virus, parainfluenza virus (PIV) type 3, influenza virus A and adenoviruses were 63.1, 14.7, 6.7, 6.7 and 6.2% of the total of 761 virus-specific episodes. Influenza virus B, PIV1 and PIV2 were each responsible for approximately 1% of the episodes. AOM was diagnosed in 870 URI cases (43.4%) and in 43.3% of cases associated with a virus-positive NPA. The latter figure was clearly higher (57.7%) for RS virus-positive specimens.

CONCLUSIONS

The seasonal coincidence of URI and AOM demonstrated the obvious role of URI in the pathogenesis of AOM. The occurrence of rhinoviruses and RS virus in URI was strikingly more common than that of any other virus tested. Although rhinoviruses were definitely the most frequently found viruses in NPA specimens, the association of RS virus with concurrent AOM was relatively higher than that of any other virus.

Risk factors for respiratory tract infections in children aged 2-5 years

OBJECTIVE

To study risk factors for respiratory tract infections (RTIs) in children aged 2-5 years.

DESIGN

A questionnaire was used to chart the number of visits to doctors and the number of antibiotics courses because of RTIs during a 1-year period. The risk factors studied were age, sex, birth weight, breastfeeding, atopy, siblings, smoking and childcare.

SETTING

The catchment area of Oxie health centre in southern Sweden.

SUBJECTS

190 pre-school children.

MAIN OUTCOME MEASURES

Number of visits to doctors and number of antibiotics courses.

RESULTS

The risk of having to consult a doctor, as well as the risk of receiving treatment with antibiotics, because of RTIs was greater among children at daycare centres than among children who were mostly at home (adjusted OR 2.78 (95% CI 1.34-5.78) and 2.73 (1.38-5.43), respectively).

CONCLUSION

Attending a daycare centre is the most important risk factor for RTIs in children aged 2-5 years.

The relationship between otitis media with effusion and contact with other children in a british cohort studied from 8 months to 3 1/2 years. The ALSPAC Study Team. Avon Longitudinal Study of Pregnancy and Childhood

OBJECTIVE

It is generally acknowledged that otitis media with effusion is more prevalent among children attending grouped day care. This study aimed to refine this by determining the relationships with the numbers of children at the place of day care, the age of the child and the number of siblings he/she had.

METHODS

ALSPAC (the Avon Longitudinal Study of Pregnancy and Childhood) is a population based longitudinal study starting early in pregnancy and following the children throughout their lives. Nested within this study, a randomly selected group of 1590 children, the Children in Focus, were invited to attend a clinic for hands on examinations. Tympanometry was carried out at ages 8, 12, 18, 25, 31, 37 and 43 months of age. Bilateral otitis media with effusion (OME) was identified if both ears showed a flat trace. Multi-level modelling with logistic regression adjusted for a number of social and environmental influences.

RESULTS

Of the 1590 children invited to the 8-month clinic, 300 (19%) were excluded from the analysis because of failure to attend or because of missing data. The analyses were based on 1290 children. The prevalence of bilateral OME decreased with age, from 24.6% at 8 months to 11.9% at 43 months. Children with older siblings and those attending day care with four or more other children were at an increased risk of OME. The adjusted odds ratios (AOR) were 1.52 (95% confidence interval [CI] = 1.23, 1.88) and 1.36 (95% CI = 1.02, 1.82), respectively. The risk associated with older siblings declined with age and by 3 years these children were no longer more likely to have OME than children with no older siblings. No such interaction with age was found for children in group day care and these children continued to be at an increased risk over the entire age period of the study. There was no increased risk associated with day care when no other children attended (AOR = 1.18, 95% CI = 0.88, 1.58) or when one to three others were present (AOR = 1.10, 95% CI = 0.85, 1.42). Although there was no relationship with the number of hours spent in day care, children who had started attending group care with four or more other children before 9 months of age did have an increased risk compared with children starting later AOR = 1.88, 95% CI = 1.12, 3.14.

CONCLUSIONS

These results provide evidence that early contact with other children increases the risk of OME and that children attending day care with four or more other children remain at an increased risk of OME at least until 31/2 years.

Higher risk for acute childhood lymphoblastic leukaemia in Swedish population centres 1973-94. Swedish Child Leukaemia Group

A population-based sample of acute childhood leukaemia cases in Sweden 1973-94 was analysed by a geographical information system (GIS) for spatial leukaemia distribution in relation to population density. The annual incidence rate for acute lymphoblastic leukaemia (ALL) was 3.6, and for acute non-lymphoblastic leukaemia (ANLL) 0.7, cases per 100,000 children. Incidence rates in population centres, constituting 1.3% of Sweden's land area and approximately 80% of the population, compared with the rest of Sweden showed a statistically significant excess of ALL [odds ratio (OR) 1.68; 95% confidence interval (CI) 1.44-1.95], but not ANLL (OR 1.13; 95% CI 0.98-1.32). An increasing trend, however not statistically significant, was found for ALL incidence with both increasing population density in parishes and increasing degree of urbanity in municipalities. These findings support the theories that some environmental factors associated with high population density, such as infectious agents, may be of aetiological importance for childhood acute lymphoblastic leukaemia.

Health effects of passive smoking. 4. Parental smoking, middle ear disease and adenotonsillectomy in children

BACKGROUND

A systematic quantitative review was conducted of evidence relating parental smoking to acute otitis media, recurrent otitis media, middle ear effusion, and adenoidectomy and/or tonsillectomy.

METHODS

Forty five relevant publications were identified after consideration of 692 articles selected by electronic search of the Embase and Medline databases using keywords relevant to passive smoking in children. The search was completed in April 1997 and identified 13 studies of acute otitis media, nine of recurrent otitis media, five of middle ear effusion, nine of glue ear surgery, and four of adenotonsillectomy. A quantitative meta-analysis was possible for all outcomes except acute otitis media, using random effects modelling where appropriate to pool odds ratios from each study.

RESULTS

Evidence for middle ear disease is remarkably consistent, with pooled odds ratios if either parent smoked of 1.48 (95% CI 1.08 to 2.04) for recurrent otitis media, 1.38 (1.23 to 1.55) for middle ear effusion, and 1.21 (0.95 to 1.53) for outpatient or inpatient referral for glue ear. Odds ratios for acute otitis media are in the range 1.0 to 1.6. No single study simultaneously addresses selection bias, information bias and confounding, but where these have been investigated or excluded in the design or analysis, the associations with parental smoking persist virtually unchanged. Large French and British studies are inconsistent with regard to the association of parental smoking and tonsillectomy.

CONCLUSIONS

There is likely to be a causal relationship between parental smoking and both acute and chronic middle ear disease in children.

Absence due to illness among toddlers in day-care centres in relation to child group structure

The present work demonstrates a close association between illness-associated absence among children below 4 y of age in day-care, and the age-related composition of the child groups. The study, which spanned a 4 y period and is based on illness-related absence from day-care in a Stockholm suburb, shows that morbidity decreases significantly among young children as age-integration in the groups is intensified. Absence due to illness was most common in toddler groups of infants up to 3 y of age. Among sibling groups of children in the age range 0-6 y, illness-related absence was lower among toddlers compared to toddlers in age-separated groups, and significantly lower in extended sibling groups in the age range 0-12 y. Morbidity among children older than 3 y was not affected in the same way by group structure.

Risk factors for community-acquired pneumonia in children: a population-based case-control study

Risk factors for community-acquired pneumonia were studied by collecting data from all pneumonia patients (n = 201) in a defined child population between 3 months and 15 years of age during a surveillance period of 12 months, and from randomly selected healthy controls under 15 years of age (n = 250) from the same area. A structured questionnaire was used, with 409 (176 patients and 233 controls) families responding in total. The chi-square test, and the univariate and multivariate logistic regression analyses were used. The confounding effects of gender, age and place of acquisition were standardized, and the possible interactions between these variables and each individual risk factor were calculated. In the risk factor analysis, the responders were classified into 2 age groups: under 5 years and 5-14 years of age. In children under 5 years of age the significant risk factors were a history of recurrent respiratory infections during the past year [odds ratio (OR) 5.5], a history of wheezing episodes (OR 5.3), and a history of otitis media and tympanocentesis before the age of 2 years (OR 3.6). In the older children, the significant risk factors were a history of recurrent respiratory infections during the previous year (OR 3.0), and a history of wheezing periods at any age (OR 2.1). To sum up, a susceptibility to respiratory infections was found to be significantly associated with community-acquired pneumonia, and no interactions with age, gender or place of acquisition were significant. This trend was reflected by a history of wheezing and that of acute otitis media.

The child group used as a reference system when analysing frequency of morbidity in day-care centres

Morbidity frequency was analysed among children attending six day-care centres in a suburb of Stockholm, Sweden. Absence due to illness was calculated annually for each child and correlated with each child's own group. Thus a child was classified as "often sick" or "mainly healthy" in relation to the other children in the child's own group, constituting a reference system. In almost every group a "sick third" was found, whose absence due to illness was twice that of the rest of the group. Children from families of lower social standing, those with a relatively large number of siblings and those living in poor social conditions were found to be among those most often reported as sick. In such families, smoking was more commonplace. These parents more often lived in a rented apartment than in a single detached owner house. Multiple linear regression analysis revealed that young mothers and children with several siblings had the strongest correlation with absence due to illness of the proband child. Increasing maternal age revealed improvement vis-à-vis all socioeconomic parameters investigated, reflecting an improvement in standing correlated to less sick children.