Episodes Of Lower Respiratory Tract Infection Research Articles

Correlation of Influenza Vaccination and the COVID-19 Severity

The pandemic of COVID-19 is evolving worldwide, and it is associated with high mortality and morbidity. There is a growing need to discuss the elements of a coordinated strategy to control the spread and mitigate the severity and mortality of COVID-19. H1N1 vaccine and streptococcus pneumonia vaccines are available. The current analysis was performed to correlate the severity of COVID-19 and influenza (H1N1) vaccination statistics and also influenza lower respiratory tract incidence. There is a correlation between COVID-19 related mortality and morbidity and influenza vaccination status, which appears protective. The tendency of correlation is more visualized as the pandemic is evolving. The case incidence and recovery parameters also showed a beneficial trend. Since evolutionarily, influenza is close to SARS-CoV-2 viruses and shares some common epitopes and mechanisms, partial protection is possible to reduce the COVID-19 related severity using the influenza vaccination. In countries where influenza immunization is less, there is a correlation between lower respiratory tract infections (LRI) and influenza attributable to lower respiratory tract infections incidence and COVID-19 severity, which is beneficial. WHO regions with an increased incidence of LRI associated mortality was associated with a reduction in COVID-19 mortality by about 16%. Independently low values of the influenza LRI parameter are significantly associated with all levels of COVID-19 mortality(>200 to >1000/million, P200 to >800/million (P400/million had beta coefficient of -0.501, CI -0.971 to -0.031 p=0.037, >500/million the beta coefficient was -0.59, CI -1.116 to -0.065, p=0.028, >600/million the beta coefficient was -0.541, CI -1.068 to -0.013, P=0.045, and for COVID-19 mortality >700/million the beta coefficient was -0.694, CI -1.414 to +0.026 P= 0.059 (December 12, 2020). The calculated odds ratio from beta coefficient, i.e., odds ratio=exp(beta coefficient) shows a significant odds ratios for influenza LRI parameter which is about 0.4 and 1-odds ratio of about 0.6 or 60% protection if the parameter is corrected. For influenza LRI incidence*population density the calculated odds ratio for an average beta coefficient [-2.5 and e^(-2.5)=0.08] across various cut-offs was 0.08 and 1-odds ratio of 0.92 which is nearing 1, which indicates the event (=1 or COVID-19 mortality) would happen in these areas with low influenza LRI and low population density which is discussed in the paper. ROC curve analysis (December 11 data) shows a cut off of 397/100 000 has a sensitivity of 88.9% (54 to 99.8) and specificity of 76.3% (69.4 to 82) and PPV (positive predictive value) 16.3 and NPV (negative predictive value) 99.2 and (likelihood ratio, LR) LR+ 3.751 and LR- 0.146 with an AUC of 0.837 to indicate COVID-19 mortality of >900/million. The low influenza LRI parameter is associated with COVID-19 case fatality rates of >2 percent. Also, recent other studies show the benefits of influenza and pneumococcal vaccines in reducing Covid19 severity.Latest results: In the logistic regression model inclusive of the parameters-influenza LRI incidence, Influenza LRI*Population density, population density and population in numbers, influenza LRI parameter had beta or standardised coefficients of -1.192 (-2.168 to -0.216, P=0.017, data Jan 9, 2021) to indicate COVID-19 mortality >1000/million (corresponding odds ratios 0.303 CI 0.11 to 0.805. By partial least square regression (PLS-R regression) the influenza LRI had standardised coefficient of -0.21(-0.34 to -0.08), and for influenza LRI*population density the standardised coefficient was -0.092 (-0.142 to 0.041). For COVID-19 mortality >400/million the influenza LRI*population density had a beta regression value of -2.1(CI -3.63 to -0.6, P=0.006, Jan 9, 2021) and the corresponding odds ratio was 0.122, CI 0.026 to 0.548. By partial least square (PLS) regression the influenza LRI had a standardised coefficient of -0.133 (CI-0.286 to 0.02), and influenza LRI*population density had a standardised coefficient of -0.129(CI-0.18 to 0.07). ROC curve shows cut-off of influenza LRI parameter 477/100 000 has a sensitivity of 93.8%, specificity of 75.9%, PPV 27.3% and NPV 99.2%, LR+ 3.891 and LR- 0.082 to indicate a COVID-19 mortality of >1000/million. Independent, influenza LRI and Influenza LRI*population density is associated with COVID-19 mortality of various cut-offs from 300 to 1000/million (PConclusion: In countries or regions with low influenza LRI incidence, influenza vaccine (single dose) will be protective against COVID-19 severity. This strategy will be more beneficial in countries/areas with lesser population density. Also, the addition of pneumococcal vaccines (single dose) would further lessen COVID-19 severity in areas with a low incidence of influenza LRI and lower respiratory tract infections. These are useful interim measures before COVID-19 vaccines are delivered in the routine practise worldwide.

Genetic susceptibility to asthma increases the vulnerability to indoor air pollution.

IntroductionIndoor air pollution and maternal smoking during pregnancy are associated with respiratory symptoms in infants, but little is known about the direct association with lung function or interactions with genetic risk factors. We examined associations of exposure to indoor particulate matter with a 50% cut-off aerodynamic diameter of 10 µm (PM10) and maternal smoking with infant lung function and the role of gene–environment interactions.MethodsData from the Drakenstein Child Health Study, a South African birth cohort, were analysed (n=270). Lung function was measured at 6 weeks and 1 year of age, and lower respiratory tract infection episodes were documented. We measured pre- and postnatal PM10 exposures using devices placed in homes, and prenatal tobacco smoke exposure using maternal urine cotinine levels. Genetic risk scores determined from associations with childhood-onset asthma in the UK Biobank were used to investigate effect modifications.ResultsPre- and postnatal exposure to PM10 as well as maternal smoking during pregnancy were associated with reduced lung function at 6 weeks and 1 year as well as with lower respiratory tract infection in the first year. Due to a significant interaction between the genetic risk score and prenatal exposure to PM10, infants carrying more asthma-related risk alleles were more susceptible to PM10-associated reduced lung function (pinteraction=0.007). This interaction was stronger in infants with Black African ancestry (pinteraction=0.001) and nonexistent in children with mixed ancestry (pinteraction=0.876).ConclusionsPM10 and maternal smoking exposures were associated with reduced lung function, with a higher susceptibility for infants with an adverse genetic predisposition for asthma that also depended on the infant's ancestry.

Maternal psychosocial risk factors and lower respiratory tract infection (LRTI) during infancy in a South African birth cohort.

ObjectiveTo investigate the association between maternal antenatal and/or postnatal psychosocial risk factors (including depression, psychological distress, alcohol abuse and intimate partner violence (IPV) and infant lower respiratory tract infection (LRTI) in a low- and middle-income-country (LMIC).Study designPregnant women (n = 1137) enrolled in a South African birth cohort study, the Drakenstein Child Health Study (DCHS) were longitudinally assessed for psychosocial risk factors including depression, psychological distress, alcohol abuse and/or intimate partner violence (IPV). Infants were followed from birth until one year of age for the development of LRTI by active surveillance. Two outcomes were evaluated: any LRTI, and severe and/or hospitalised LRTI. Logistic regression was used to identify associations between individual maternal psychosocial risk factors and LRTI outcomes. Analyses stratified by age were also performed to determine which age groups related to infant LRTI were linked with maternal psychosocial risk factors.ResultsThere were 606 LRTI episodes in 369 infants in the first year (crude incidence rate = 0.53 episodes per person-year, 95%CI: 0.50; 0.56); 31% (n = 186) of episodes were severe or hospitalised events. Maternal psychosocial risk factors were associated with LRTI and severe LRTI, particularly postnatal and long-term maternal psychological distress, antenatal maternal alcohol consumption, and postnatal maternal IPV. Age stratified analyses found that antenatal maternal alcohol consumption was associated with early infant LRTI, while antenatal maternal depression was linked with infant severe LRTI between 3 and 6 months of age, and postnatal maternal IPV was associated with early LRTI and severe forms of LRTI.ConclusionThe associations between maternal psychosocial risk factors and infant LRTI highlight the potential value of screening for maternal psychosocial risk factors in clinical settings and developing targeted interventions. Such interventions may not only improve maternal well-being, but also help reduce the burden of infant LRTI in LMIC settings.

Effect of Vitamin D Supplementation in the Prevention of Recurrent Pneumonia in Under-Five Children.

To assess the effect of vitamin D supplementation in the prevention of recurrent pneumonia in under-five children. The present one year 8 months longitudinal, community-based randomized controlled study included a total of 100 under-five children with pneumonia. Children were divided into two groups: intervention group (Group I: standard treatment with vitamin D 300,000IU; n = 50) and control group (Group C: standard treatment only; n = 50). As nine samples were hemolyzed, groups I and C comprised of 46 and 45 children, respectively. The children were followed up for 1 y and signs of upper respiratory tract infections (URTI), lower respiratory tract infections (LRTI), vitamin D deficiency, and vitamin D toxicity were recorded. The male to female ratio in group C and I was 1.27:1 and 1.5:1, respectively (P = 0.420). Age, gender, birth, anthropometric and clinical characteristics, and feeding habits were not statistically significant (P > 0.05) between both the cohorts (Group C and I). Children with reduced vitamin D levels were high in group C (25) when compared to the group I (15). During all the follow-ups, the URTI and LRTI episodes, severity of pneumonia, number of hospital admissions, complications, mean episodes of LRTI, and mean duration of LRTI were comparable between group I and group C (P > 0.05). Overall, the present study highlights that oral vitamin D (300,000IU bolus dose quarterly) has some beneficial effect in the prevention of recurrent pneumonia in under-five children, although, not to a significant degree. Hence, it is recommended that further studies are required to demonstrate a significant effect of vitamin D in the prevention of pneumonia.

Mortality, morbidity, and hospitalisations due to influenza lower respiratory tract infections, 2017: an analysis for the Global Burden of Disease Study 2017

SummaryBackgroundAlthough the burden of influenza is often discussed in the context of historical pandemics and the threat of future pandemics, every year a substantial burden of lower respiratory tract infections (LRTIs) and other respiratory conditions (like chronic obstructive pulmonary disease) are attributable to seasonal influenza. The Global Burden of Disease Study (GBD) 2017 is a systematic scientific effort to quantify the health loss associated with a comprehensive set of diseases and disabilities. In this Article, we focus on LRTIs that can be attributed to influenza.MethodsWe modelled the LRTI incidence, hospitalisations, and mortality attributable to influenza for every country and selected subnational locations by age and year from 1990 to 2017 as part of GBD 2017. We used a counterfactual approach that first estimated the LRTI incidence, hospitalisations, and mortality and then attributed a fraction of those outcomes to influenza.FindingsInfluenza LRTI was responsible for an estimated 145 000 (95% uncertainty interval [UI] 99 000–200 000) deaths among all ages in 2017. The influenza LRTI mortality rate was highest among adults older than 70 years (16·4 deaths per 100 000 [95% UI 11·6–21·9]), and the highest rate among all ages was in eastern Europe (5·2 per 100 000 population [95% UI 3·5–7·2]). We estimated that influenza LRTIs accounted for 9 459 000 (95% UI 3 709 000–22 935 000) hospitalisations due to LRTIs and 81 536 000 hospital days (24 330 000–259 851 000). We estimated that 11·5% (95% UI 10·0–12·9) of LRTI episodes were attributable to influenza, corresponding to 54 481 000 (38 465 000–73 864 000) episodes and 8 172 000 severe episodes (5 000 000–13 296 000).InterpretationThis comprehensive assessment of the burden of influenza LRTIs shows the substantial annual effect of influenza on global health. Although preparedness planning will be important for potential pandemics, health loss due to seasonal influenza LRTIs should not be overlooked, and vaccine use should be considered. Efforts to improve influenza prevention measures are needed.FundingBill & Melinda Gates Foundation.

Estimates of the global, regional, and national morbidity, mortality, and aetiologies of lower respiratory tract infections in 195 countries: a systematic analysis for the Global Burden of Disease Study 2015

SummaryBackgroundThe Global Burden of Diseases, Injuries, and Risk Factors (GBD) Study 2015 provides an up-to-date analysis of the burden of lower respiratory tract infections (LRIs) in 195 countries. This study assesses cases, deaths, and aetiologies spanning the past 25 years and shows how the burden of LRI has changed in people of all ages.MethodsWe estimated LRI mortality by age, sex, geography, and year using a modelling platform shared across most causes of death in the GBD 2015 study called the Cause of Death Ensemble model. We modelled LRI morbidity, including incidence and prevalence, using a meta-regression platform called DisMod-MR. We estimated aetiologies for LRI using two different counterfactual approaches, the first for viral pathogens, which incorporates the aetiology-specific risk of LRI and the prevalence of the aetiology in LRI episodes, and the second for bacterial pathogens, which uses a vaccine-probe approach. We used the Socio-demographic Index, which is a summary indicator derived from measures of income per capita, educational attainment, and fertility, to assess trends in LRI-related mortality. The two leading risk factors for LRI disability-adjusted life-years (DALYs), childhood undernutrition and air pollution, were used in a decomposition analysis to establish the relative contribution of changes in LRI DALYs.FindingsIn 2015, we estimated that LRIs caused 2·74 million deaths (95% uncertainty interval [UI] 2·50 million to 2·86 million) and 103·0 million DALYs (95% UI 96·1 million to 109·1 million). LRIs have a disproportionate effect on children younger than 5 years, responsible for 704 000 deaths (95% UI 651 000–763 000) and 60.6 million DALYs (95ÙI 56·0–65·6). Between 2005 and 2015, the number of deaths due to LRI decreased by 36·9% (95% UI 31·6 to 42·0) in children younger than 5 years, and by 3·2% (95% UI −0·4 to 6·9) in all ages. Pneumococcal pneumonia caused 55·4% of LRI deaths in all ages, totalling 1 517 388 deaths (95% UI 857 940–2 183 791). Between 2005 and 2015, improvements in air pollution exposure were responsible for a 4·3% reduction in LRI DALYs and improvements in childhood undernutrition were responsible for an 8·9% reduction.InterpretationLRIs are the leading infectious cause of death and the fifth-leading cause of death overall; they are the second-leading cause of DALYs. At the global level, the burden of LRIs has decreased dramatically in the last 10 years in children younger than 5 years, although the burden in people older than 70 years has increased in many regions. LRI remains a largely preventable disease and cause of death, and continued efforts to decrease indoor and ambient air pollution, improve childhood nutrition, and scale up the use of the pneumococcal conjugate vaccine in children and adults will be essential in reducing the global burden of LRI.FundingBill & Melinda Gates Foundation.

Community-acquired lower respiratory tract infections in HIV-infected patients on antiretroviral therapy: predictors in a contemporary cohort study.

We aimed to assess variables associated with lower respiratory tract infection (LRTI) among HIV-infected adults using ART. A cohort study of HIV-infected patients aged ≥18years, enrolled from 2000 to 2015, on ART for at least 60days, with primary outcome as the 1st episode of LRTI during follow-up. The independent variables included were sex at birth, age, race/skin color, educational level, tobacco smoking, alcohol use, cocaine use, diabetes mellitus, CD4 count, HIV viral load, influenza and pneumococcal vaccination. Extended Cox proportional hazards models accounting for time-updated variables were fitted to assess LRTI predictors. 2669 patients were included; median follow-up was 3.9years per patient. LRTI was diagnosed in 384 patients; incidence rate was 30.7/1000 PY. In the unadjusted Cox extended models, non-white race [crude hazard ratio (cHR) 1.28, p=0.020], cocaine use (cHR 2.01, p<0.001), tobacco smoking (cHR 1.34, p value 0.007), and HIV viral load ≥400 copies/mL (cHR 3.40, p<0.001) increased the risk of LRTI. Lower risk of LRTI was seen with higher educational level (cHR 0.61, p<0.001), rise in CD4 counts (cHR 0.81, p<0.001, per 100 cells/mm3 increase), influenza (cHR 0.60, p=0.002) and pneumococcal vaccination (cHR 0.57, p<0.001). In the adjusted model, aHR for CD4 count was 0.86, for cocaine use 1.47 and for viral load ≥400 copies 2.20. LRTI has a high incidence in HIV-infected adults using ART. Higher CD4 counts and undetectable viral loads were protective, as were pneumococcal and influenza vaccines.

Epidemiology and Outcomes of Respiratory Virus Infections in Adult Acute Leukemia and Hematopoietic Stem Cell Transplant Patients

BACKGROUNDRespiratory virus infections (RVI) are significant cause of morbidity and mortality in adult patients with hematopoietic stem cell transplant (HSCT) recipients, causing delay in administering chemotherapy and HSCT, increased hospital stay and in occasionally resulting in mortality. In 2008, the FDA approved the use of multiplex PCR assay to detect respiratory viruses. Our institution has been using the multiplex PCR technique for approximately four years. With this technology the time to diagnosis of a RVI became shorter and detection of multiple viruses at the same time became feasible.RVIs have been studied more exclusively in the HSCT population where lymphopenia has been identified for poor outcomes. These infections have been less well studied in the acute leukemia population. This report, however, encompasses both patient populations. The natural progression of RVIs apart from influenza is poorly understood. The viruses isolated from the upper respiratory tract, development of lower respiratory tract infection (LRI), as well as overall survival of the patients identified with RVIs are reported here.STUDY DESIGNThis is a retrospective cohort study of adult patients (>=18yrs) with acute leukemia and/or after HSCT diagnosed with laboratory documented RVI between May 1st 2010 and March 1st2014. A list of positive RVIs from multiplex PCR was retrieved from the hospital laboratory based on patients with specific ICD-9 codes.RESULTSBetween May 2010 to March 2014, there were 208 episodes of RVI in 122 patients. Out of these, 77 patients were post-HSCT and 45 patients had acute leukemia without undergoing HSCT. Out of these episodes, 85 were caused by rhinovirus, 37 by coronavirus, 18 by RSV, 35 by parainfluenza, 15 by influenza, 12 by metapneumovirus, 3 by adenovirus, 3 by poly-viral infection. 189 episodes were initially diagnosed as an upper respiratory tract infection (URI). There were 47 episodes of LRI; of these 32 (16.9%) had a prior URI with rhinovirus (n=13), coronavirus (n=5), parainfluenza (n=4), RSV (n=4), influenza (n=3) and poly-viral infections (n=2). 15 (7.2%) episodes were LRI at initial presentation (4 metapneumovirus, 4 parainfluenza, 2 RSV, 3 rhinovirus, 1 coronavirus, 1 adenovirus). Out of the 122 patients there were 7 deaths (5.7%).CONCLUSIONThe availability of multiplex PCR has allowed for the identification of respiratory viruses responsible for URI in this patient population. Most of these infections have limited clinical consequences. However, in our study 25% of the episodes either presented with or progressed to LRI. The exact role of respiratory virus in causing LRI is difficult to determine in a retrospective study. DisclosuresOff Label Use: Treating MDS with one of these regimens: (1) nelfinavir, (2) bortezomib, (3) metformin + simvastatin, (4) metformin + seliciclib, (5) nelfinavir + bortezomib, (6) nelfinavir + ruxolitinib, (7) nelfinavir + simvastatin, (8) nelfinavir + sorafenib, (9) nelfinavir + trametinib, (10) ponatinib + bortezomib, (11) nelfinavir + ponatinib, and (12) trametinib + simvastatin.

Clinical risk factors for life-threatening lower respiratory tract infections in children: a retrospective study in an urban city in Malaysia.

AimLower respiratory tract infections (LRTIs) are an important cause of morbidity and mortality, especially in low income countries. The aim of this study was to determine risk factors of life-threatening LRTIs in hospitalised children in Malaysia.MethodsThis retrospective study included children aged less than 18 years admitted for LRTIs over 13 months in a tertiary referral centre in Kuala Lumpur, Malaysia. Neonates, children with asthma and those with either no or a normal chest radiograph were excluded. Life-threatening infection was defined as that needing non-invasive ventilation or admission to the paediatric intensive care unit. Routine blood investigations and nasopharyngeal secretion results (bacterial and viral) were obtained. Chest radiographs were reviewed by a designated radiologist. Environmental data (rainfall, particulate matter ≤10 µm [PM10] and air pollution index [API]) was obtained from the respective government departments.ResultsThree hundred and ninety-one episodes of LRTIs were included. Viruses were implicated in 48.5% of LRTIs, with respiratory syncytial virus (RSV) being detected in 44% of viral LRTIs. Forty-six (11.8%) children had life-threatening disease and the overall mortality rate was 1.3% (5 children). RSV was detected in 26% of children with life-threatening LRTIs. In multivariate logistic regression, chronic lung disease, presenting history of apnoea and signs of hypoxia, was associated with life threatening LRTIs. Increased LRTI admissions were associated with low rainfall but not PM10 nor API. Of those on follow-up, 39% had persistent respiratory symptoms.ConclusionOne in nine children admitted with LRTI had a life-threatening LRTI. The aetiology was viral in almost half of admitted children. RSV was detected in a quarter of children with life-threatening LRTIs. Children who present with LRTIs and either have chronic lung disease, presenting history of apnoea or signs of hypoxia, should be observed carefully as the risk of deterioration to life-threatening illness is high.

Investigating the early-life determinants of illness in Africa: the Drakenstein Child Health Study

Respiratory disease is the predominant cause of illness in children globally. We describe a unique multidisciplinary South African birth cohort, the Drakenstein Child Health Study (DCHS), to investigate the incidence,...

Prenatal exposure to p,p′-DDE and p,p′-DDT in relation to lower respiratory tract infections in boys from a highly exposed area of Mexico

BackgroundPrenatal exposure to 1,1-dichloro-2,2-bis(p-chlorophenyl)ethylene (p,p′-DDE), the major breakdown product of DDT, has been associated with recurrent lower respiratory tract infections (LRTIs) in infants. However, epidemiological investigations are limited. ObjectiveTo assess the association of prenatal exposure to p,p′-DDE and p,p′-DDT with the occurrence of LRTI in boys from Chiapas, a highly exposed area of Mexico. MethodsWe analyzed data from 747 singleton boys whose prenatal exposure to p,p′-DDE and p,p′-DDT was determined in maternal serum drawn at delivery (2002–2003). LRTI (i.e., pneumonia, bronchiolitis, and other illness of the bronchi) experienced by the children were reported by their mothers during in-person interviews. The median age of the children when they were last seen was 21.4 months (quartiles 19.1 and 25.3 months). ResultsMedian exposure to p,p′-DDE in this population was higher (2.7µg/g lipid) than recent U.S. levels (0.20µg/g). There were 0.19 episodes of LRTI per child-year. After adjusting for potential confounders, children in the highest category of p,p′-DDE (>9.00µg/g) exposure compared to those in the lowest (≤3.00µg/g) had an adjusted incidence rate ratio (aIRR) of LRTI of 0.77 (95% confidence interval [CI], 0.41–1.46). The corresponding aIRR for p,p′-DDT (≥2.00µg/g compared to ≤0.25µg/g) was 0.65 (95% CI: 0.30–1.39). ConclusionAn association of prenatal exposure to p,p′-DDE and p,p′-DDT with LRTI during childhood was not supported in this population with relatively high levels of exposure.

Lower Respiratory Tract Infections Associated with Rhinovirus during Infancy and Increased Risk of Wheezing during Childhood. A Cohort Study

Background and ObjectivesAlthough association between respiratory syncytial virus infection and later asthma development has been established, little is known about the role of other respiratory viruses. Rhinovirus was considered a mild pathogen of the upper respiratory tract but current evidence suggests that rhinovirus is highly prevalent among children with lower respiratory tract infections (LRTI). The aim of the study was to evaluate whether LRTI hospitalization associated with rhinovirus during infancy was associated with an increased risk of wheezing – a proxy measure of asthma – during childhood.MethodsDuring a 12 months period, all infants <1 year admitted to Manhiça District Hospital with symptoms of LRTI who survived the LRTI episode, were enrolled in the study cohort. Nasopharyngeal aspirates were collected on admission for viral determination and study infants were classified according to presence or not of rhinovirus. The study cohort was passively followed-up at the Manhiça District Hospital for up to 4 years and 9 months to evaluate the association between LRTI associated with rhinovirus in infancy and wheezing during childhood.Findings and ConclusionsA total of 220 infants entered the cohort; 25% of them had rhinovirus detected during the LRTI episode as opposed to 75% who tested negative for rhinovirus. After adjusting for sex and age and HIV infection at recruitment, infants hospitalized with LRTI associated with rhinovirus had higher incidence of subsequent visits with wheezing within the year following hospitalization [Rate ratio=1.68, (95% confidence interval=1.02-2.75); Wald test p-value = 0.039]. No evidence of increased incidence rate of visits with wheezing was observed for the remaining follow-up period. Our data suggest a short term increased risk of wheezing after an initial episode of LRTI with RV.

Clinical and epidemiologic profile of lower respiratory tract infections associated with human bocavirus

Acute viral bronchiolitis (AVB) remains the leading cause of lower respiratory tract infection (LRTI) in infants under 2 years of age. Advances in molecular methods for virus detection have led to the identification of new infectious agents implicated in the development of AVB, such as human bocavirus (HBoV). To ascertain the frequency, seasonality, and clinical behavior of HBoV detection in a series of episodes of LRTI. The frequency of HBoV was assessed in children with LRTI episodes, aged 1-24 months, seen at the emergency department of Hospital da Criança Santo Antônio, Porto Alegre, Brazil, between May 2007 and July 2008. Virus-specific polymerase chain reaction was used for detection. A total of 455 nasal secretion samples were collected from 433 patients over a 14-month period. Of these, 60 were positive for HBoV (13.2%). Mean age was 7.9 months and 55% of patients were male. Just over half of patients were under 6 months of age (53.3%). Wheezing was the presenting respiratory complaint in 51.7%. Of the 60 patients, 80% were admitted to a pediatric ward. Diarrhea was present in nine patients (18%). Co-detection was a frequent finding in our sample, occurring in 95% of cases. In our series, the distribution of HBoV was clearly seasonal and was influenced by temperature, relative humidity, and precipitation. We conclude that HBoV detection in infants with AVB and recurrent wheezing of viral etiology in Brazil is similar to that reported in other countries. The clinical course of HBoV detection is no different from that of other respiratory viruses commonly found in this age range.

The incidence and aetiology of hospitalised community-acquired pneumonia among Vietnamese adults: a prospective surveillance in Central Vietnam

BackgroundLower respiratory tract infection (LRTI) including Community-acquired pneumonia (CAP) is a common infectious disease that is associated with significant morbidity and mortality. The patterns of aetiological pathogens differ by region and country. Special attention must be paid to CAP in Southeast Asia (SEA), a region facing rapid demographic transition. Estimates burden and aetiological patterns of CAP are essential for the clinical and public health management. The purposes of the study are to determine the incidence, aetiological pathogens, clinical pictures and risk factors of community-acquired pneumonia (CAP) in the Vietnamese adult population.MethodsA prospective surveillance for hospitalised adult CAP was conducted in Khanh Hoa Province, Central Vietnam. All adults aged ≥15 years with lower respiratory tract infections (LRTI) admitted to a provincial hospital from September 2009 to August 2010 were enrolled in the study. Patients were classified into CAP and non-pneumonic LRTI (NPLRTI) according to the radiological findings. Bacterial pathogens were identified from sputum samples by the conventional culture and polymerase chain reaction (PCR) for Streptococcus pneumoniae, Haemophilus influenzae, and Moraxella catarrhalis; 13 respiratory viruses were identified from nasopharyngeal specimens by PCR.ResultsOf all 367 LRTI episodes examined, 174 (47%) were CAP. Older age, the presence of underlying respiratory conditions, and higher index score of smoking were associated with CAP. The one-year estimated incidence of hospitalised adult CAP in our study population was 0.81 per 1,000 person years. The incidence increased considerably with age and was highest among the elderly. The case fatality proportion of hospitalised CAP patients was 9.8%. Among 286 sputum samples tested for bacterial PCR, 79 (28%) were positive for H. influenzae, and 65 (23%) were positive for S. pneumoniae. Among 357 samples tested for viral PCR, 73 (21%) were positive for respiratory viruses; influenza A (n = 32, 9%) was the most common.ConclusionsThe current adult CAP incidence in Vietnam was relatively low; this result was mainly attributed to the young age of our study population.

Severe brain atrophy in the elderly as a risk factor for lower respiratory tract infection

BackgroundThe purpose of this study is to determine whether elderly subjects with severe brain atrophy, which is associated with neurodegeneration and difficulty swallowing (dysphagia), are more susceptible to lower respiratory tract infections (LRTI), including pneumonia.MethodsThe severity of brain atrophy was assessed by computed tomography in 51 nursing home residents aged 60–96 years. The incidence of LRTI, defined by body temperature ≥ 38.0°C, presence of two or more respiratory symptoms, and use of antibiotics, was determined over 4 years. The incidence of LRTI was compared according to the severity and type of brain atrophy.ResultsThe incidence rate ratio of LRTI was significantly higher (odds ratio 4.60, 95% confidence interval 1.18–17.93, fully adjusted P = 0.028) and the time to the first episode of LRTI was significantly shorter (log-rank test, P = 0.019) in subjects with severe brain atrophy in any lobe. Frontal and parietal lobe atrophy was associated with a significantly increased risk of LRTI, while temporal lobe atrophy, ventricular dilatation, and diffuse white matter lesions did not influence the risk of LRTI.ConclusionElderly subjects with severe brain atrophy are more susceptible to LRTI, possibly as a result of neurodegeneration causing dysphagia and silent aspiration. Assessing the severity of brain atrophy might be useful to identify subjects at increased risk of respiratory infections in a prospective manner.

OUTDOOR NO 2 EXPOSURE IS ASSOCIATED WITH PERSISTENT COUGH DURING THE FIRST YEAR OF LIFE

Background and Aims: Because children’s lungs and immune system are not completely developed they are more susceptible to respiratory disease as well as more vulnerable to ambient pollution. We assessed the relation between prenatal and postnatal NO2 levels and the development of Lower Respiratory Tract Infections (LRTI), wheezing and persistent cough during the first year of life. Methods: Study population were 352 children from a birth cohort in Valencia, Spain. Prenatal exposure to NO2 was measured at 93 sampling sites spread over the study area during four different sampling periods of 7 days each. It was modelled for each residential address through land use regression using the empirical measurements and geographic information systems data. Postnatal exposures were measured indoor and outdoor the residence with passive samplers during 14 days once in each home. Outcomes studied were any episode of LRTI during the child's first year of life diagnosed by a doctor (bronchitis, bronchiolitis or pneumonia), wheezing (defined as whistling sounds coming from the chest), and persistent cough (more than three consecutive weeks). Outcomes and potential confounders were obtained from structured questionnaires. Multiple logistic regression was used to explore associations. Results: Cumulative incidence (CI) was 30.40% for LRTI (23.01% bronchiolitis, 11.93% bronchitis and 1.42% pneumonia), 26.14% for wheezing and 6.25% for persistent cough. Adjusted odds ratio (95% confidence interval) per 10 µg/m3 increment in postnatal outdoor NO2 concentration was for persistent cough 1.40 (1.02-1.92). We also found evidence of an association with bronchiolitis, bronchitis and persistent cough in different prenatal periods, although it was not statistically significant. Conclusions: Our results support that exposure to outdoor NO2 during first year increase the risk of persistent cough. Support statement: ‘‘Instituto de Salud Carlos III’’ (G03/176), FIS-FEDER 03/1615, 04/1509, 04/1112, 06/1213, RCESP C03/09, the fellowship for research training FI05/01109, “Enrique Nájera 2006” prize for young researchers and Conselleria Sanitat GV 16/2009.

Outdoor, but not indoor, nitrogen dioxide exposure is associated with persistent cough during the first year of life

Background and aims Because their lungs and immune system are not completely developed, children are more susceptible to respiratory disease and more vulnerable to ambient pollution. We assessed the relation between prenatal and postnatal nitrogen dioxide (NO 2) levels and the development of lower respiratory tract infections (LRTI), wheezing and persistent cough during the first year of life. Methods The study population consisted of 352 children from a birth cohort in Valencia, Spain. Prenatal exposure to NO 2, a marker of traffic related air pollution was measured at 93 sampling sites spread over the study area during four different sampling periods of 7 days each. It was modeled for each residential address through land use regression using the empirical measurements and data from geographic information systems. Postnatal exposure was measured once inside and outside each home using passive samplers for a period of 14 days. Outcomes studied were any episode of LRTI during the child's first year of life diagnosed by a doctor (bronchitis, bronchiolitis or pneumonia), wheezing (defined as whistling sounds coming from the chest), and persistent cough (more than three consecutive weeks). Outcomes and potential confounders were obtained from structured questionnaires. Multiple logistic regression was used to identify associations. Results The cumulative incidence (CI) at first year of life was 30.4% for LRTI (23.0% bronchiolitis, 11.9% bronchitis and 1.4% pneumonia), 26.1% for wheezing and 6.3% for persistent cough. The adjusted odds ratio (95% confidence interval) per 10 μg/m 3 increment in postnatal outdoor NO 2 concentration was 1.40 (1.02–1.92) for persistent cough. We also found some pattern of association with LRTI, bronchiolitis, bronchitis, wheezing and persistent cough in different prenatal periods, although it was not statistically significant. Conclusions Our results indicate that exposure to outdoor, but not indoor, NO 2 during the first year of life increases the risk of persistent cough.

The Epidemiology of Respiratory Syncytial Virus Lower Respiratory Tract Infections in Children Less than 5 Years of Age in Indonesia

Although the epidemiology of respiratory syncytial virus (RSV) lower respiratory tract infections (LRI) is well known in industrialized countries, the burden in developing Asian countries is not well studied. To define the burden of RSV disease in children <5 years of age in rural and urban Indonesia, infants and children were enrolled from peri-urban and rural subdistricts, in the following 2 cohorts: (a) a cross-sectional cohort of approximately 100 children from each of 2 subdistricts in the following 5 age groups: 3 to 5, 6 to 8, 9 to 11, 12 to 23, and 24 to 48 months; (b) a birth cohort of all newborns in both subdistricts during the 28 months of the study. All subjects were visited weekly at home. Children with World Health Organization-defined LRI or wheezing had a nasal wash for detection of RSV using an enzyme immunoassay and polymerase chain reaction. Of the 2014 children studied, 1074 were in the cross-sectional and 940 in the newborn cohorts. Of the 802 episodes of LRI, 163 were caused by RSV. The RSV LRI incidence per 1000 child-years (C-Y) was higher in rural areas (57.25 vs. 38.54), P < 0.05. No RSV LRI occurred in the first 2 months of life and the peak incidence was in the 6- to 8-month-old infants (103/1000 C-Y). The rates were lowest in those <6 months, 16.5 per 1000 C-Y, compared with 83.1 per 1000 C-Y in those 6 to 11 months of age (P < 0.001), 66.99 in those 12 to 23 months of age, and 28.1 in 2- to 5-year-olds. In Indonesia, the incidence of RSV LRI in the first 6 months of life is relatively low with most disease occurring in older children.

Iron-containing micronutrient powder provided to children with moderate-to-severe malnutrition increases hemoglobin concentrations but not the risk of infectious morbidity: a randomized, double-blind, placebo-controlled, noninferiority safety trial

A link between the provision of iron and infectious morbidity has been suggested, particularly in children with malnutrition. Two meta-analyses concluded that iron is not harmful, but malnourished children were underrepresented in most available studies. This study evaluated the effect of iron-containing micronutrient powder (iron MNP) on infectious morbidities when provided to children with moderate-to-severe malnutrition and anemia. A randomized, double-blind, placebo-controlled, noninferiority safety trial using a 2-mo course of daily iron MNP or placebo powder (PP) was conducted in 268 Bangladeshi children aged 12-24 mo with moderate-to-severe malnutrition (weight-for-age z score ≤ -2) and a hemoglobin concentration between 70 and 110 g/L. The primary endpoint was a composite of diarrhea, dysentery, and lower respiratory tract infection episodes (DDL) recorded through home visits every 2 d during the intervention and then weekly for 4 mo. The noninferiority margin was 1.2. Secondary endpoints included hemoglobin and anthropometric changes at 2 and 6 mo. All deaths and hospitalizations were documented. To capture seasonal variation, the study was repeated in the winter and summer with 2 distinct groups. An intention-to-treat analysis of recurrent events was performed by using the univariate Anderson-Gill model. The baseline characteristics of the subjects were similar. Analysis of phase-aggregated DDL data showed that iron MNP was not inferior to PP (relative risk: 0.81; 95% CI: 0.62, 1.04) and improved hemoglobin concentrations (P < 0.0001). We recorded no deaths, and hospitalizations were rare. Iron MNP is safe and efficacious when provided to children aged 12-24 mo with moderate-to-severe malnutrition and anemia. This trial is registered at clinicaltrials.gov as NCT00530374.

Clinical Characteristics of Post-Infectious Bronchiolitis Obliterans

Purpose : Bronchiolitis obliterans (BO), an uncommon chronic obstructive lung disease in children, is most often seen following a severe lower respiratory tract infection (LRTI). We investigated the clinical characteristics, etiology, possible risk factors, radiological findings, and response to treatment in children diagnosed with post-infectious BO. Methods : A retrospective study was performed on 62 patients diagnosed with post-infectious BO based on clinical and high-resolution computed tomography (HRCT) findings from 2005 to 2010. Forty-eight age-matched children who were admitted with the first episode of LRTI and did not subsequently develop BO were also studied as control subjects. Results : Median ages at diagnosis and initial insult were 28 and 17 months, respectively. The median duration from initial LRTI until diagnosis was 5 months. Children who developed BO showed more respiratory compromise during their acute episodes of LRTI than those who did not. Symptom severity score decreased significantly after adequate treatment, which was significantly greater in patients treated with pulse steroid therapy than those treated with other controllers. Conclusion : The results suggest that the development of post-infectious BO should be suspected in the children showing persistent respiratory symptoms after severe LRTIs. They also suggest that adequate treatment including pulse steroid therapy may improve clinical status and the prognosis of these patients. [Pediatr Allergy Respir Dis(Korea) 2011;21:156-164]