Neonatal vitamin A deficiency and its impact on acute respiratory infections among preschool Inuit children

OBJECTIVE: To assess if vitamin A concentration in umbilical cord blood is associated with incidence and severity of respiratory infections in preschool Inuit children from Nunavik (Québec, Canada). METHOD: The medical charts of 305 children were reviewed from 0 to 5 years of age. The association between vitamin A concentration in umbilical cord plasma and the incidence rates of acute otitis media (AOM), lower respiratory tract infections (LRTIs) and hospitalization rates for LRTIs was evaluated using Poisson regression. RESULTS: Compared to children with vitamin A concentration > or =20 microg/dl, adjusted rate ratios (RR) for children below 20 microg/dl ranged between 1.06-1.62 for AOM, 1.12-1.34 for LRTIs, and 1.09-1.43 for hospitalization for LRTIs. Most RRs were statistically significant for AOM and LRTIs, but not for hospitalization for LRTIs. CONCLUSION: Neonatal vitamin A deficiency appears to be a significant risk factor for AOM and LRTIs in this population.     

Effect of prenatal exposure to polychlorinated biphenyls on incidence of acute respiratory infections in preschool Inuit children

OBJECTIVE: We set out to assess whether environmental prenatal exposure to polychlorinated biphenyls (PCBs) is associated with incidence of acute respiratory infections in preschool Inuit children. STUDY DESIGN: We reviewed the medical charts of 343 children from 0 to 5 years of age and evaluated the associations between PCB-153 concentration in umbilical cord plasma and the incidence rates of acute otitis media (AOM) and of upper and lower respiratory tract infections (URTIs and LRTIs, respectively). RESULTS: The incidence rates of AOM and LRTIs were positively associated with prenatal exposure to PCBs. Compared with children in the first quartile of exposure (least exposed), children in fourth quartile (most exposed) had rate ratios of 1.25 (p<0.001) and 1.40 (p<0.001) for AOM and LRTIs, respectively. There was no association between prenatal PCB exposure and incidence rate of URTIs or hospitalization. CONCLUSION: Prenatal exposure to PCBs could be responsible for a significant portion of respiratory infections in children of this population.     

Bronchiolitis-associated outpatient visits and hospitalizations among American Indian and Alaska Native children--United States, 1990-2000

Respiratory syncytial virus (RSV) is the most common cause of lower respiratory tract infection (LRTI) in young children worldwide. Approximately half of all LRTI-associated hospitalizations are caused by bronchiolitis, with RSV accounting for 50%-80% of all bronchiolitis cases. Bronchiolitis is an infection of the bronchial and bronchiolar epithelial cells, with subsequent inflammation and edema resulting in airway obstruction. This process manifests clinically as cough, wheezing, tachypnea, and respiratory distress. Because of the association between bronchiolitis and RSV infection, bronchiolitis is a good indicator of RSV disease; therefore, prevention strategies for RSV should reduce the rate of bronchiolitis. Rates of bronchiolitis-associated hospitalization for American Indian/Alaska Native (AI/AN) children are approximately twice that for the general population of U.S. children. This report describes the first estimate of rates of outpatient bronchiolitis-associated visits and updates rates of bronchiolitis-associated hospitalizations in these populations. Rates of bronchiolitis-associated outpatient visits and hospitalizations were higher for AI/AN children than for other U.S. children, and hospitalization rates for both groups increased during 1990-2000. This report underscores the high burden of bronchiolitis and the need for effective prevention programs for AI/AN communities.     

Childhood injuries: a population-based study of emergency room visits in Jerusalem

A study of childhood injuries of 0-17-year-old Jewish children based on emergency room records of the four major hospitals and the first aid stations was conducted in Jerusalem during 1986. The incidence of visits was 99.7/1000 child-years with 95% confidence intervals (CI) = 98.0-101.5. The rate was 97.2/1000 child-years (CI = 94.4-100.0) among the 0-5-year-old, 114.6/1000 child-years (CI = 111.3-118.0) in the 6-12 age group, and was 93.6/1000 child-years (CI = 90.1-97.1) among 13-17-year-old. The male to female rate ratio was 1.7 for the 0-5-year-olds, 2.1 for the 6-12-year-olds and 2.3 for the 13-17-year-olds. The most frequent causes of injuries were falls, 38.5/1000 child-years (CI = 37.4-39.6), being struck or caught, 21.1/1000 child-years (CI = 20.3-21.9), and road accidents, 5.4/1000 child-years (CI = 5.0-5.8). Only burns among children aged 6 years and over and poisoning among 13-17-year-olds showed a higher incidence among females than among males. The head was the most frequently injured part of the body (45.2/1000 child-years, CI = 44.0-46.4). Head injuries decreased as age increased, while injuries to the extremities and trunk increased with increasing age. Two per cent of the injured children were admitted to hospital.     

Persistent and acute diarrhoea as the leading causes of child mortality in urban Guinea Bissau.

An investigation of child mortality in a semi-urban community, Bandim II, in the capital of Guinea Bissau was carried out from April 1987 to March 1990. 153 deaths were recorded among 1426 live-born children who were followed for 2753 child-years. The under-five mortality risk was 215 per 1000 children (95% confidence interval [CI] 176-264), infant mortality 94 per 1000 (95% CI 73-115), and perinatal mortality 52 per 1000 (95% CI 41-63). By prospective registration of morbidity, post-mortem interviews, and examination of available hospital records, a presumptive cause of death was established in 86% of the deaths. Persistent and acute diarrhoea were the most frequent causes of death, accounting for 43 and 31 deaths per 1000 children, respectively. Fever deaths (possibly malaria), neonatal deaths, acute respiratory infections, and measles were other frequent causes. The access to health services was relatively easy: 75% of the children who died had attended for treatment at a hospital or a health centre. It is important to find ways of preventing and managing persistent diarrhoea, the major cause of death, and to improve the control of acute diarrhoea by a targeted approach.     

Vitamin A concentration in umbilical cord blood of infants from three separate regions of the province of Québec (Canada)

BACKGROUND: Inuit women from Northern Québec have been shown to consume inadequate quantities of vitamin A. This study was conducted to evaluate the prevalence of blood vitamin A deficiency in newborns from 3 distinct populations of the province of Québec. METHODS: 594 newborns were included in this study (375 Inuit newborns from northern Québec (Nunavik), 107 Caucasian and Native newborns from the Lower Northern Shore of the Saint-Lawrence River (LNS) and 112 newborns from Southern Québec where clinical vitamin A deficiency is uncommon). Mothers were recruited at delivery and vitamin A (retinol) was analyzed from umbilical cord blood samples by reversed-phase high-pressure liquid chromatography. RESULTS: Nunavik and LNS newborns had significantly lower mean vitamin A concentrations in cord blood compared to Southern Québec participants (15.7 microg/dL, 16.8 microg/dL and 20.4 microg/dL respectively). The differences observed were similar when adjusted for sex and birthweight. Results also showed that 8.5% of Nunavik newborns and 12.2% of LNS newborns were below 10.0 microg/dL, a level thought to be indicative of blood vitamin A deficiency in neonates. CONCLUSION: These data suggest that a carefully planned vitamin A supplementation program during pregnancy in Nunavik and LNS might be indicated to promote healthy infant development.     

Acute infections and environmental exposure to organochlorines in Inuit infants from Nunavik

The Inuit population of Nunavik (Canada) is exposed to immunotoxic organochlorines (OCs) mainly through the consumption of fish and marine mammal fat. We investigated the effect of perinatal exposure to polychlorinated biphenyls (PCBs) and dichlorodiphenyldichloroethylene (DDE) on the incidence of acute infections in Inuit infants. We reviewed the medical charts of a cohort of 199 Inuit infants during the first 12 months of life and evaluated the incidence rates of upper and lower respiratory tract infections (URTI and LRTIs, respectively), otitis media, and gastrointestinal (GI) infections. Maternal plasma during delivery and infant plasma at 7 months of age were sampled and assayed for PCBs and DDE. Compared to rates for infants in the first quartile of exposure to PCBs (least exposed), adjusted rate ratios for infants in higher quartiles ranged between 1.09 and 1.32 for URTIs, 0.99 and 1.39 for otitis, 1.52 and 1.89 for GI infections, and 1.16 and 1.68 for LRTIs during the first 6 months of follow-up. For all infections combined, the rate ratios ranged from 1.17 to 1.27. The effect size was similar for DDE exposure but was lower for the full 12-month follow-up. Globally, most rate ratios were > 1.0, but few were statistically significant (p < 0.05). No association was found when postnatal exposure was considered. These results show a possible association between prenatal exposure to OCs and acute infections early in life in this Inuit population.     

Impact of pneumococcal conjugate vaccine in children morbidity and mortality in Peru: Time series analyses

Streptococcus pneumoniae is the leading cause of bacterial pneumonia, meningitis and sepsis in children worldwide. Despite available evidence on pneumococcal conjugate vaccine (PCV) impact on pneumonia hospitalizations in children, studies demonstrating PCV impact in morbidity and mortality in middle-income countries are still scarce. Given the disease burden, PCV7 was introduced in Peru in 2009, and then switched to PCV10 in late 2011. National public healthcare system provides care for 60% of the population, and national hospitalization, outpatient and mortality data are available.We thus aimed to assess the effects of routine PCV vaccination on pneumonia hospitalization and mortality, and acute otitis media (AOM) and all cause pneumonia outpatient visits in children under one year of age in Peru.We conducted a segmented time-series analysis using outcome-specific regression models. Study period was from January 2006 to December 2012. Data sources included the National information systems for hospitalization, mortality, outpatient visits, and RENACE, the national database of aggregated weekly notifications of pneumonia and other acute respiratory diseases (both hospitalized and non-hospitalized). Study outcomes included community acquired pneumonia outpatient visits, hospitalizations and deaths (ICD10 codes J12-J18); and AOM outpatient visits (H65-H67). Monthly age- and sex-specific admission, outpatient visit, and mortality rates per 100,000 children aged <1 year, as well as weekly rates for pneumonia and AOM recorded in RENACE were estimated.After PCV introduction, we observed significant vaccine impact in morbidity and mortality in children aged <1 year. Vaccine effectiveness was 26.2% (95% CI 16.9–34.4) for AOM visits, 35% (95% CI 8.6–53.8) for mortality due to pneumonia, and 20.6% (95% CI 10.6–29.5) for weekly cases of pneumonia hospitalization and outpatient visits notified to RENACE. We used secondary data sources which are usually developed for other non-epidemiologic purposes. Despite some data limitations, our results clearly demonstrate the overall benefit of PCV vaccination in Peru.     

Burden of medically attended influenza infection and cases averted by vaccination – United States, 2013/14 through 2015/16 influenza seasons

BackgroundIn addition to preventing hospitalizations and deaths due to influenza, influenza vaccination programs can reduce the burden of outpatient visits for influenza. We estimated the incidence of medically-attended influenza at three geographically diverse sites in the United States, and the cases averted by vaccination, for the 2013/14 through 2015/16 influenza seasons.MethodsWe defined surveillance populations at three sites from the United States Influenza Vaccine Effectiveness Network. Among these populations, we identified outpatient visits laboratory-confirmed influenza via active surveillance, and identified all outpatient visits for acute respiratory illness from healthcare databases. We extrapolated the total number of outpatient visits for influenza from the proportion of surveillance visits with a positive influenza test. We combined estimates of incidence, vaccine coverage, and vaccine effectiveness to estimate outpatient visits averted by vaccination.ResultsAcross the three sites and seasons, incidence of medically attended influenza ranged from 14 to 54 per 1000 population. Incidence was highest in children aged 6 months to 9 years (33 to 70 per 1000) and lowest in adults aged 18–49 years (21 to 27 per 1000). Cases averted ranged from 9 per 1000 vaccinees (Washington, 2014/15) to 28 per 1000 (Wisconsin, 2013/14).DiscussionSeasonal influenza epidemics cause a considerable burden of outpatient medical visits. The United States influenza vaccination program has caused meaningful reductions in outpatient visits for influenza, even in years when the vaccine is not well-matched to the dominant circulating influenza strain.     

Respiratory syncytial virus infection: denominator-based studies in Indonesia, Mozambique, Nigeria and South Africa

OBJECTIVE: To assess the burden of respiratory syncytial virus (RSV)-associated lower respiratory infections (LRI) in children in four developing countries. METHODS: A WHO protocol for prospective population-based surveillance of acute respiratory infections in children aged less than 5 years was used at sites in Indonesia, Mozambique, Nigeria and South Africa. RSV antigen was identified by enzyme-linked immunosorbent assay performed on nasopharyngeal specimens from children meeting clinical case definitions. FINDINGS: Among children aged < 5 years, the incidence of RSV-associated LRI per 1000 child-years was 34 in Indonesia and 94 in Nigeria. The incidence of RSV-associated severe LRI per 1000 child-years was 5 in Mozambique, 10 in Indonesia, and 9 in South Africa. At all study sites, the majority of RSV cases occurred in infants. CONCLUSION: These studies demonstrate that RSV contributes to a substantial but quite variable burden of LRI in children aged < 5 years in four developing countries. The possible explanations for this variation include social factors, such as family size and patterns of seeking health care; the proportion of children infected by human immunodeficiency syndrome (HIV); and differences in clinical definitions used for obtaining samples. The age distribution of cases indicates the need for an RSV vaccine that can protect children early in life.     

Lower respiratory tract illness in the first two years of life: epidemiologic patterns and costs in a suburban pediatric practice.

The epidemiologic patterns and the economic impact of acute lower respiratory tract illness (LRTI) in children under age two were studied using data collected from November 1, 1971-August 30, 1975 in a suburban pediatric practice in Monroe County, New York. LRTI was responsible for 23 illness episodes per 100 child-years among children in their first two years of life. This indicates that a cohort of 100 children might be anticipated to have 46 LRTI episodes from birth until their second birthday. The majority of episodes correlated with the presence of four viruses in the community, most commonly respiratory syncytial virus. The minimal, estimated direct cost of LRTI in the first two years of life based on 1984 cost data was equivalent to $35.14 for every child and was comprised of hospitalization cost ($19.68) and ambulatory care cost ($15.46). Hospitalization costs attributable to LRTI comprised at least 2.5 per cent of all hospitalization costs in this age group. Immunization against the four most common respiratory viruses, at a reasonable cost per child immunized, would appear to be cost beneficial.     

Population-based study of acute respiratory infections in children,Greenland

Acute respiratory infections (ARI) are frequent in Inuit children, in terms of incidence and severity. A cohort of 294 children <2 years of age was formed in Sisimiut, a community on the west coast of Greenland, and followed from 1996 to 1998. Data on ARI were collected during weekly visits at home and child-care centers; visits to the community health center were also recorded. The cohort had respiratory symptoms on 41.6% and fever on 4.9% of surveyed days. The incidence of upper and lower respiratory tract infections was 1.6 episodes and 0.9 episodes per 100 days at risk, respectively. Up to 65% of the episodes of ARI caused activity restriction; 40% led to contact with the health center. Compared with studies from other parts of the world, the incidence of ARI appears to be high in Inuit children.     

n-3 Fatty acids and cardiovascular disease risk factors among the Inuit of Nunavik

BACKGROUND: Inuit traditionally consume large amounts of marine foods rich in n-3 fatty acids. Evidence exists that n-3 fatty acids have beneficial effects on key risk factors for cardiovascular disease. OBJECTIVE: Our goal was to verify the relation between plasma phospholipid concentrations of the n-3 fatty acids eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) and various cardiovascular disease risk factors among the Inuit of Nunavik, Canada. DESIGN: The study population consisted of 426 Inuit aged 18-74 y who participated in a 1992 health survey. Data were obtained through home interviews and clinical visits. Plasma samples were analyzed for phospholipid fatty acid composition. RESULTS: Expressed as the percentage of total fatty acids, geometric mean concentrations of EPA, DHA, and their combination in plasma phospholipids were 1.99%, 4.52%, and 6.83%, respectively. n-3 Fatty acids were positively associated with HDL-cholesterol concentrations and inversely associated with triacylglycerol concentrations and the ratio of total to HDL cholesterol. In contrast, concentrations of total cholesterol, LDL cholesterol, and plasma glucose increased as n-3 fatty acid concentrations increased. There were no significant associations between n-3 fatty acids and diastolic and systolic blood pressure and plasma insulin. CONCLUSIONS: Consumption of marine products, the main source of EPA and DHA, appears to beneficially affect some cardiovascular disease risk factors. The traditional Inuit diet, which is rich in n-3 fatty acids, is probably responsible for the low mortality rate from ischemic heart disease in this population.     

Environmental exposure to polychlorinated biphenyls and placental CYP1A1 activity in Inuit women from northern Québec

Some polychlorinated biphenyl (PCB) congeners are CYP1A1 inducers, and induction of this enzyme in the placenta has been linked to adverse effects on fetal development. The objective of this study was to determine if the body burden of PCBs is related to placental CYP1A1 activity in Inuit women from Nunavik (northern Québec), a population highly exposed to organochlorines. Placenta and cord blood samples were obtained from 35 Inuit women and 30 women from a southern Québec community exposed to background levels of organochlorines. We measured PCB concentrations in all cord plasma samples and in a subset of placenta samples from the Nunavik group and assessed CYP1A1 activity (ethoxyresorufin-O-deethylase; EROD) in placental microsomes from all participants. Concentrations of PCBs in cord plasma were strongly correlated to those in placenta (Pearson's r) = 0.77-0.97, p < 0.001) and were on average 4-fold higher in Inuit women than in southern Québec women [for PCB 153, the geometric means (geometric SDs) were 83.3 (1.9) ng/g lipid vs. 16.9 (1.6) ng/g lipid, respectively]. Despite this difference in PCB body burden, both study groups had similar EROD activities when data were stratified according to tobacco smoking. Although simple correlation analysis first showed that placental EROD activity was correlated with PCB 153 plasma concentration in the Nunavik group, a multivariate analysis failed to demonstrate a significant contribution of PCBs to EROD activity when tobacco smoking was included in the analysis. We conclude that dietary exposure to PCBs in Inuit women from Nunavik does not significantly influence EROD activity in the placenta, implicating tobacco smoking as the major modulating factor.     

Self-reported prevalence of warts in children and GP consultation

Objective: Respiratory infections are a frequent causes of medical attendance. Influenza viruses increases this phenomena. The aim of this study was to prospectively identify GPs’ increased work in terms of visits and time. Methods: Over a period of five months 5 GPs recorded sex, age, number and place of visits, telephone consultations of the patients visited for acute respiratory disease (ARD)which included acute respiratory infections (ARI), influenza (FLU) and Influenza-like illness (ILI). Upper respiratory tract infections (URTI) were classified as sinusitis, rhinitis, otitis, tonsillitis, pharyngitis, laryngitis, Lower respiratory tract infections (LRTI) were classified as tracheitis, bronchitis, pneumonia, bronchopneumonia, acute episodes of chronic obstructive pulmonary disease (COPD) and asthma. FLU and ILI were considered two different entities on the basis of symptoms. Results: Acute respiratory disease increase of 22 patients attending every GP's office monthly (from 176 to 198 total visits). 6542 patients were observed. The incidence of ARD was 33.5% (2191: 1091 female and 1100 males). URTI affected 944 patients, LRTI 739, FLU 328 and ILI 180. The increase in home visits grew from 10 to 36. Each home visit took from 15 to 45 minutes. In a high number of cases (236), home visits were necessary for sick-leave certificates. FLU (54%) and LRTI (37.5%) required more attention, and they were the primary causes for visits. Telephone consultations took place for all ILI or FLU of minor severity and in young people.

Conclusion: During the winter there is an increased work-load for GPs due to the diffusion of influenza virus and respiratory tract diseases. “Burn out syndrome” is increasing among the GPs. Territorial GPs’ action is highly efficacious. Patients self-certification should be evaluated. Vaccine therapy could be more effective if done on a larger population. More research is needed.     

The clinical impact of multiple prevention strategies for respiratory syncytial virus infections in infants and high-risk toddlers in the United States

BackgroundRespiratory syncytial virus (RSV) remains a leading cause of medically-attended acute respiratory infection in infants and children. With multiple preventative interventions under development, accurate estimates of health care resource utilization are essential for policy decision making.MethodsWe developed a literature-based decision-tree model that estimated annual medically-attended RSV (MA-RSV) lower respiratory tract infection (LRTI) and non-LRTI episodes in the US for all infants and for high-risk toddlers. The model accounted for the gestational age and birth-month of infants, and the seasonal variation in RSV incidence. The impact of no prophylaxis, palivizumab, maternal vaccine, and long-acting monoclonal antibody (mAb) interventions was estimated.ResultsWe estimated 1.23 million (range: 0.96 million–1.40 million) annual MA-RSV LRTI/non-LRTI episodes comprised of 1.19 million (range: 0.93 million–1.36 million) emergency department (ED) and outpatient visits, and 39,040 (range: 32,726–45,851) hospitalizations. Outpatient and ED visits were comprised of 586,034 (range: 430,595–718,868) LRTIs and 608,733 (range: 495,705–644,658) non-LRTIs. The long-acting mAb intervention resulted in the greatest number of averted outpatient and ED episodes (310,997 [53%] LRTIs; 284,305 [47%] non-LRTIs) and hospitalizations (21,845 [56%]). Full-term infants constitute the highest proportion of episodes across all interventions.ConclusionsMA-RSV disease is substantial in infants and high-risk toddlers. Long-acting mAbs are most effective at reducing the number of MA-RSV LRTI/non-LRTI episodes, and the only intervention that prevents disease in older infants (≥6 months old).     

Risk factors for acute respiratory tract infections in young Greenlandic children

Acute respiratory infections cause considerable morbidity among Inuit children, but there is very little information on the risk factors for these infections in this population. To identify such factors, the authors performed a prospective community-based study of acute respiratory infections in an open cohort of 288 children aged 0-2 years in the town of Sisimiut, Greenland. Between July 1996 and August 1998, children were monitored weekly, and episodes of upper and lower respiratory tract infections were registered. Risk factor analyses were carried out using a multivariate Poisson regression model adjusted for age. Risk factors for upper respiratory tract infections included attending a child-care center (relative risk = 1.7 compared with home care) and sharing a bedroom with adults (relative risk = 2.5 for one adult and 3.1 for two adults). Risk factors for lower respiratory tract infections included being a boy (relative risk = 1.5), attending a child-care center (relative risk = 3.3), exposure to passive smoking (relative risk = 2.1), and sharing a bedroom with children aged 0-5 years (relative risk = 2.0 for two other children). Breastfeeding tended to be protective for lower respiratory tract infections. The population-attributable risk of lower respiratory tract infections associated with passive smoking and child-care centers was 47% and 48%, respectively. The incidence of acute respiratory infections among Inuit children may be reduced substantially through public health measures.     

Effect of dietary calcium intake on lead exposure in Inuit children attending childcare centres in Nunavik

High blood lead levels (BLLs) can be found in Inuit from Nunavik. At the same time, various nutrients such as calcium could lower lead absorption and toxicity. We examined the effect of dietary calcium intakes on BLLs in 245 preschool Inuit children attending childcare centres in Nunavik. Calcium intake was assessed with one 24-h dietary recall and BLLs were determined by inductively coupled plasma mass spectrometry in whole blood samples. Multiple imputation was performed to deal with missing data. Median blood lead concentration was 0.08?μmol/L. A high proportion of children did not meet the Estimated Average Requirement for vitamin D intake (73?%) and, to a lower extent, for calcium (20?%). Calcium intake was negatively associated with BLLs (?p = 0.0001) while child’s age and energy intake were positively associated with BLLs (?p = 0.015 and p = 0.024, respectively). Consuming traditional foods rich in calcium as well as milk and alternatives may protect against lead exposure.