Risk Of Upper Respiratory Infections Research Articles

Association between air pollution and upper respiratory tract infection in hospital outpatients aged 0–14 years in Hefei, China: a time series study

ObjectiveTo investigate the association between air pollution and upper respiratory tract infection (URTI) in children aged 0–14 years in Hefei, China in 2014–2015. Study designAn ecological method (i.e. generalised additive model [GAM]) was used to explore the effects of air pollutants on paediatric hospital outpatients with URTI. MethodsGAM was used to evaluate the lag effects (including lag0 to lag6, lag01 and lag06) between daily changes in particulate matter (PM10), fine particulate matter (PM2.5), sulphur dioxide (SO2), nitrogen dioxide (NO2), ozone (O3) and carbon monoxide (CO) and the number of hospital outpatients with URTI in 2014–2015, after controlling for the confounding effects of long-term trends, seasonality, day of the week, public holidays and meteorological factors. ResultsPM10, PM2.5, SO2, NO2 and CO in the single-pollutant models had significant positive effects on the number of paediatric hospital outpatients with URTI. It was found that per 10 μg/m3 increasing in concentrations of PM10 at lag3, PM2.5, SO2, NO2 and CO at lag06 were associated with an increase of Excess risk (ER) with 0.15% (95% CI: 0.07%∼0.23%), 0.38% (95% CI: 0.17%∼0.60%), 2.92% (95% CI: 1.88%∼3.97%), 4.47% (95% CI: 3.69%∼5.25%) and 0.05% (95% CI: 0.02%∼0.08%), respectively. Only NO2 remained significantly positively associated with the number of hospital outpatients with URTI in the full-pollutant models, and ERs were 4.72% (95% CI = 3.76%–5.69%) and 4.70% (95% CI = 3.76%–5.65%) per 10 μg/m3 increase in NO2 in Model 1 (including PM10, SO2, NO2, O3 and CO) and Model 2 (including PM2.5, SO2, NO2, O3 and CO), respectively. ConclusionThis study showed that short-term exposure to air pollution was associated with increased risk of URTI among paediatric hospital outpatients aged 0–14 years in Hefei. NO2 was the major air pollutant affecting the daily number of paediatric hospital outpatients with URTI.

Cage size, movement in and out of housing during daily care, and other environmental and population health risk factors for feline upper respiratory disease in nine North American animal shelters.

Upper respiratory infection (URI) is not an inevitable consequence of sheltering homeless cats. This study documents variation in risk of URI between nine North American shelters; determines whether this reflects variation in pathogen frequency on intake or differences in transmission and expression of disease; and identifies modifiable environmental and group health factors linked to risk for URI. This study demonstrated that although periodic introduction of pathogens into shelter populations may be inevitable, disease resulting from those pathogens is not. Housing and care of cats, particularly during their first week of stay in an animal shelter environment, significantly affects the rate of upper respiratory infection.

Yogurt supplemented with probiotics can protect the healthy elderly from respiratory infections: A randomized controlled open-label trial.

PurposeTo evaluate whether yogurt supplemented with a probiotic strain could protect middle-aged and elderly people from acute upper respiratory tract infections (URTI) using a randomized, blank-controlled, parallel-group design.Patients and methodsTwo hundred and five volunteers aged ≥45 years were randomly divided into two groups. The subjects in the intervention group were orally administered 300 mL/d of yogurt supplemented with a probiotic strain, Lactobacillus paracasei N1115 (N1115), 3.6×107 CFU/mL for 12 weeks, while those in the control group retained their normal diet without any probiotic supplementation. The primary outcome was the incidence of URTI, and changes in serum protein, immunoglobulins, and the profiles of the T-lymphocyte subsets (total T-cells [CD3+], T-helper cells [CD4+], and T-cytotoxic-suppressor cells [CD8+]) during the intervention were the secondary outcomes.ResultsCompared to the control group, the number of persons diagnosed with an acute URTI and the number of URTI events significantly decreased in the intervention group (P=0.038, P=0.030, respectively). The risk of URTI in the intervention group was evaluated as 55% of that in the control group (relative risk =0.55, 95% CI: 0.307–0.969). The change in the percentage of CD3+ cells in the intervention group was significantly higher than in the control group (P=0.038). However, no significant differences were observed in the total protein, albumin, globulin, and prealbumin levels in both groups (P>0.05).ConclusionThe study suggested that yogurt with selected probiotic strains such as N1115 may reduce the risk of acute upper tract infections in the elderly. The enhancement of the T-cell-mediated natural immune defense might be one of the important underlying mechanisms for probiotics to express their anti-infective effects.

High-Dose Vitamin D

Low levels of serum vitamin D are suggested to be associated with increased risk for viral upper respiratory infection (vURI). In a five-year trial,

Long-term use of inhaled corticosteroids and risk of upper respiratory tract infection in chronic obstructive pulmonary disease: a meta-analysis

Recent studies have suggested that inhaled corticosteroids (ICS) may be associated with higher risks of tuberculosis and pneumonia in patients with COPD. However, it is not known whether ICS increases the risk of upper respiratory tract infection (URTI). Aim of this study was to explore the relationship between ICS and URTI. Through a comprehensive literature search of PubMed, EMBASE, Cochrane Library, and Google Scholar from inception to March 2016, we identified randomized controlled trials of ICS therapy lasting at least 6 months. A meta-analysis by the Peto approach was also conducted to generate summary estimates comparing ICS with non-ICS treatment on the risk of URTI. A total of 14 studies involving 19,777 subjects were considered in the meta-analysis. Compared with non-ICS treatment, ICS were associated with a significantly increased risk of URTI (Peto OR: 1.16; 95% CI: 1.05–1.29; I2 = 9%; p = .004). Subgroup analyzes were performed for different dose, high-dose ICS was associated with a significantly increased risk of URTI (Peto OR: 1.19; 95% CI: 1.05–1.34; I2 = 0%; p = .005), whereas low-dose ICS showed a non-significant increased risk of URTI (Peto OR: 1.10; 95% CI: 0.91–1.33; I2 = 0%; p = .32). Moreover, fluticasone was observed with an increased risk of URTI but not mometasone; high-dose fluticasone treatment was associated with a significantly higher risk of URTI but not low-dose. These results suggested to us that ICS use may increase the risk of URTI in patients with COPD, but it should be further investigated.

Protective Effects of Fermented Milk with Selected Probiotics Against Acute Upper Respiratory Tract Infections by Enhancement of Immunity of the Elderly: An Open‐Label Trial

Background and ObjectiveAgeing caused immunosenescence and malnutrition would down‐regulate the immunity of the elderly. Such changes in the immunity can greatly increase the susceptibilities to attack by infective agents. Recent studies have observed that some fermented milk containing special probiotics might enhance the host immunity by which to protect the elderly from the infections. This study was conducted to evaluate the possible influence of fermented milk containing a selected probiotics, Lactobacillus paracasei N1115 (N1115), on the susceptibility to acute upper respiratory tract infections(URTI) and related immune function in the middle‐aged and the elderly.MethodsVolunteers aged ≥45 years were recruited and selected by a three‐step screening test. The selected subjects were randomly assigned to intervention group and control group. The intervention group received fermented milk made from N1115 (3.6×107CFU/mL) 300mL per day for 12 weeks, while the control group could not intake any probiotics supplements. Information such as URTI symptoms, defecation, diet, exercise and antibiotic usage were recorded weekly. Blood samples were collected to test serum proteins, immunoglobulins and T cell subsets before and after intervention.ResultsCompared to the control group, both the number of persons diagnosed with an acute URTI and the number of URTI events were significantly higher in the intervention group (P=0.038, P=0.030, respectively). The risk of URTI in the intervention group was 55% of those in the control group evaluated (RR=0.55, 95%CI: 0.307~0.969). The change of percentage of CD3 cell subsets from baseline in intervention group was significantly higher than that of control group (P=0.038). Percentage of CD4 and CD8, immunoglobulin(Ig) A and IgM were almost the same in both groups (P>0.05). Additionally, there was no significant difference in total protein, albumin, globulin and prealbumin in two groups (P>0.05).ConclusionsFermented milk containing selected probiotic strain such as N1115 could enhance T cell mediated natural immune deference by which to reduce the risk of acute upper tract infections in the elderly.

Lower cathelicidin concentrations in Irish athletes compared to controls: a role for vitamin D?

The biologically active vitamin D metabolite (1[alpha]-dihydroxyvitamin D) has been linked to regulation of human cathelicidin antimicrobial peptide (LL-37) in vitro. Recent studies in athletes indicate that vitamin D inadequacy is associated with lower concentrations of LL-37 and that this may increase risk of upper respiratory tract infection (URTI). PURPOSE: To compare circulating LL-37 concentrations between athletes and healthy controls and to establish if total 25-hydroxyvitamin D (25[OH]D) was a significant determinant of this antimicrobial peptide.METHODS: A total of 221 stored, fasted plasma samples from male and female athletes (elite rugby n=12, elite boxing n=12, Gaelic football n=77) and age and sex-matched healthy controls (n=120) were analysed in duplicate for LL-37 concentrations using an enzyme-linked immunosorbent assay. Total 25(OH)D concentrations were quantified by liquid chromatography-tandem mass spectrometry as part of the previous studies. Comparison of 25(OH)D and LL-37 concentrations between athletes and controls was made using Mann-Whitney U tests. Linear regression was used to test if 25(OH)D concentration was a significant determinant of LL-37 concentration after adjusting for season of sampling.RESULTS: Median [IQR] 25(OH)D concentrations were 49.76[39.37] and 28.90[23.55] nmol/L for athletes and healthy controls respectively, P<0.001. LL-37 concentrations were significantly lower in athletes compared to healthy controls (26.92[17.04] versus 47.91[59.93] ng/mL respectively, P<0.001). Nevertheless 25(OH)D was not found to be a significant determinant of LL-37 concentration in athletes ([beta]=0.052, P=0.611) or healthy controls ([beta]=0.170, P=0.224).CONCLUSION: Our preliminary findings demonstrate a significant difference in LL-37 concentration between athletes and the general population. Yet the significant positive association between 25(OH)D and LL-37 concentrations reported in endurance athletes may not apply to those competing in intermittent sports; possibly owing to a decreased likelihood of experiencing exercise-induced immunosuppression resulting from prolonged high-intensity exercise. Further studies are required to determine if lower LL-37 concentrations translate into athletes being at greater risk of URTI than the general population.

Association between serum vitamin D, retinol and zinc status, and acute respiratory infections in underweight and normal-weight children aged 6-24 months living in an urban slum in Bangladesh.

We conducted a longitudinal assessment in 466 underweight and 446 normal-weight children aged 6-24 months living in the urban slum of Dhaka, Bangladesh to determine the association between vitamin D and other micronutrient status with upper respiratory tract infection (URI) and acute lower respiratory infection (ALRI). Incidence rate ratios of URI and ALRI were estimated using multivariable generalized estimating equations. Our results indicate that underweight children with insufficient and deficient vitamin D status were associated with 20% and 23-25% reduced risk of URI, respectively, compared to children with sufficient status. Underweight children, those with serum retinol deficiency were at 1·8 [95% confidence interval (CI) 1·4-2·4] times higher risk of ALRI than those with retinol sufficiency. In normal-weight children there were no significant differences between different vitamin D status and the incidence of URI and ALRI. However, normal-weight children with zinc insufficiency and those that were serum retinol deficient had 1·2 (95% CI 1·0-1·5) times higher risk of URI and 1·9 (95% CI 1·4-2·6) times higher risk of ALRI, respectively. Thus, our results should encourage efforts to increase the intake of retinol-enriched food or supplementation in this population. However, the mechanisms through which vitamin D exerts beneficial effects on the incidence of childhood respiratory tract infection still needs further research.

High Viremia and Wasting Before Antiretroviral Therapy Are Associated With Pneumonia in Early-Treated HIV-Infected Kenyan Infants.

Human immunodeficiency virus (HIV)-infected children are particularly susceptible to acute respiratory infections (ARIs). We determined incidence and cofactors for ARIs in HIV-infected infants receiving antiretroviral therapy (ART). Human immunodeficiency virus-infected infants initiated ART at ≤12 months of age and were observed monthly for 2 years in Nairobi. Acute respiratory infection rates and cofactors were determined using Andersen-Gill models, allowing for multiple events per infant. Among 111 HIV-infected infants, median age at ART initiation was 4.5 months. Pre-ART median CD4% was 19%, and 29% had wasting. During 24-months follow-up while on ART, upper respiratory infection (URI) and pneumonia rates were 122.6 and 34.7 per 100 person-years (py), respectively. Infants with higher pre-ART viral load (VL) (plasma HIV ribonucleic acid [RNA] ≥7 log10 copies/mL) had 4.12-fold increased risk of pneumonia (95% confidence interval [CI], 2.17-7.80), and infants with wasting (weight-for-height z-score < -2) had 2.87-fold increased risk (95% CI, 1.56-5.28). Infants with both high pre-ART VL and wasting had a higher pneumonia rate (166.8 per 100 py) than those with only 1 of these risk factors (44.4 per 100 py) or neither (17.0 per 100 py). Infants with exposure to wood fuel had significantly higher risk of URI (hazard ratio [HR] = 1.82; 95% CI, 1.44-2.28) and pneumonia (HR = 3.31; 95% CI, 1.76-6.21). In early ART-treated HIV-infected infants, higher HIV RNA and wasting before ART were independent risk factors for pneumonia. Wood fuel use was associated with URI and pneumonia. Additional data on air pollution and respiratory outcomes in HIV-infected children may help optimize interventions to improve their lung health.

Risk factors for respiratory infections among children attending day care centres.

Upper respiratory tract infection (URTI), lower respiratory tract infection (LRTI) and acute otitis media (AOM) are common in children attending day care centres. This study aimed to characterize the risk factors of URTI, LRTI and AOM in children attending day care. A cross-sectional study was conducted in children aged up to 3 years (n = 152) of six day care centres in Porto. Logistic regression was used on independent variables: mother-related, household-related, child-related and day care-related risk factors as predictors of the dependent variables: URTI, LRTI and AOM. The risk of URTI increased as the number of children decreased [odds ratio (OR) = 0.620, 95% CI = 0.411-0.935], as the area per child decreased (OR = 0.434, 95% CI = 0.206-0.914) and as the disinfection of WC/diapers-change increased (OR = 2.56, 95% CI = 1.089-6.017). There was a higher risk of URTI if nasal aspirators (OR = 6.763, 95% CI = 1.022-44.753), rather than physiologic serum (OR = 5.296, 95% CI = 1.097-25.559), were used at day care centres. The risk of LRTI increased as the household size decreased (OR = 0.213, 95% CI = 0.048-0.937) and it was higher if the child had no siblings (OR = 7.831, 95% CI = 1.065-57.578). The risk of LRTI was higher if the child was not exclusively breastfed (OR = 24.612, 95% CI = 1.108-546.530) and the risk increased as the duration of exclusive breastfeeding decreased (OR = 0.396, 95% CI = 0.170-0.920). The risk of AOM increased as the birth body mass index (OR = 2.247, 95% CI = 1.011-4.992) and weight (OR = 1.607, 95% CI = 1.014-2.545) increased and if nasal aspirators were used (OR = 6.763, 95% CI = 1.022-44.753). URTI were related with day care centres' risk factors, LRTI were associated with mother-related and household-related risk factors and AOM was connected with child-related risk factors.

Daily intake of fermented milk with Lactobacillus casei strain Shirota reduces the incidence and duration of upper respiratory tract infections in healthy middle-aged office workers

PurposeAlthough several studies have demonstrated the efficacy of probiotics for preventing upper respiratory tract infections (URTIs) in at-risk populations, including children and the elderly, few studies have investigated the efficacy of probiotics in healthy adults living normal, everyday lives. Thus, we tried to evaluate the effects of Lactobacillus casei strain Shirota-fermented milk (LcS-FM) on the incidence of URTIs in healthy middle-aged office workers.MethodsIn a randomized controlled trial, 96 eligible male workers aged 30–49 years consumed LcS-FM containing 1.0 × 1011 viable LcS cells or control milk (CM) once daily for 12 weeks during the winter season. URTI episodes were evaluated by a physician via a questionnaire of URTI symptoms.ResultsThe incidence of URTIs during the intervention period was significantly lower in the LcS-FM group than in the CM group (22.4 vs. 53.2 %, P = 0.002). The time-to-event analysis showed that the LcS-FM group had a significantly higher URTI-free rate than the CM group over the test period (log-rank test: χ2 11.25, P = 0.0008). The cumulative number of URTI episodes and cumulative days with URTI symptoms per person was lower in the LcS-FM group, and the duration per episode was shorter. Inhibition of both reductions in NK cell activity in peripheral blood mononuclear cells and increases in salivary cortisol levels was observed in the LcS-FM group.ConclusionThe results suggest that the daily intake of fermented milk with LcS may reduce the risk of URTIs in healthy middle-aged office workers, probably through modulation of the immune system.

Vitamin D and respiratory infections.

Vitamin D or 1,25-hydroxyvitamin D (1,25(OH)2 D) has a well-established role in calcium homeostasis. In recent years, the discovery of vitamin D-metabolizing enzymes and vitamin D receptor (VDR) in the lungs and various cells of the immune system has led to numerous studies conducted to evaluate its role in respiratory functions and, in particular, upper respiratory tract infections (URTIs). A PubMed literature search was done using vitamin D and respiratory infections as key words. Only clinical studies were considered. This study aimed to review recent clinical and epidemiological studies conducted in adults and children, and to evaluate the functional role of vitamin D in respiratory infections. The evaluated studies show an important immunomodulatory role of vitamin D, which reduces the incidence and risk of URTIs, both in children and in adults. Combating URTIs can be done prophylactically, associating the use of vaccines against Streptococcus pneumoniae with strengthening the immune system through supplementation with vitamin D. These actions can significantly contribute to reducing the number of URTIs, the use of antibiotics, and consequently, the rates of antimicrobial resistance.

Vitamin D3 supplementation in patients with chronic obstructive pulmonary disease (ViDiCO): a multicentre, double-blind, randomised controlled trial

Patients with chronic obstructive pulmonary disease (COPD) often have vitamin D deficiency, which is associated with increased susceptibility to upper respiratory infection-a major precipitant of exacerbation. Multicentre trials of vitamin D supplementation for prevention of exacerbation and upper respiratory infection in patients with COPD are lacking. We therefore investigated whether vitamin D3 (colecalciferol) supplementation would reduce the incidence of moderate or severe COPD exacerbations and upper respiratory infections. We did a randomised, double-blind, placebo-controlled trial of vitamin D3 supplementation in adults with COPD in 60 general practices and four Acute National Health Service Trust clinics in London, UK. Patients were allocated to receive six 2-monthly oral doses of 3 mg vitamin D3 or placebo over 1 year in a 1:1 ratio using computer-generated permuted block randomisation. Participants and study staff were masked to treatment assignment. Coprimary outcomes were time to first moderate or severe exacerbation and first upper respiratory infection. Analysis was by intention to treat. A prespecified subgroup analysis was done to assess whether effects of the intervention on the coprimary outcomes were modified by baseline vitamin D status. This trial is registered with ClinicalTrials.gov, number NCT00977873. 240 patients were randomly allocated to the vitamin D3 group (n=122) and placebo group (n=118). Vitamin D3 compared with placebo did not affect time to first moderate or severe exacerbation (adjusted hazard ratio 0·86, 95% CI 0·60-1·24, p=0·42) or time to first upper respiratory infection (0·95, 0·69-1·31, p=0·75). Prespecified subgroup analysis showed that vitamin D3 was protective against moderate or severe exacerbation in participants with baseline serum 25-hydroxyvitamin D concentrations of less than 50 nmol/L (0·57, 0·35-0·92, p=0·021), but not in those with baseline 25-hydroxyvitamin D levels of at least 50 nmol/L (1·45, 0·81-2·62, p=0·21; p=0·021 for interaction between allocation and baseline serum 25-hydroxyvitamin D status). Baseline vitamin D status did not modify the effect of the intervention on risk of upper respiratory infection (pinteraction=0·41). Vitamin D3 supplementation protected against moderate or severe exacerbation, but not upper respiratory infection, in patients with COPD with baseline 25-hydroxyvitamin D levels of less than 50 nmol/L. Our findings suggest that correction of vitamin D deficiency in patients with COPD reduces the risk of moderate or severe exacerbation. UK National Institute for Health Research.

Vitamin D supplementation and upper respiratory tract infections in adolescent swimmers: a randomized controlled trial.

Observational studies identified associations between vitamin D insufficiency (serum 25(OH)D < 30ng·ml-1) and risk of upper respiratory infection (URI). Swimmers are highly prone to URIs, which might hinder their performance. The aim of this study was to examine if vitamin D3 supplementation reduces URI burden in vitamin D-insufficient swimmers. Fifty-five competitive adolescent swimmers with vitamin D insufficiency were randomized to receive vitamin D3 (2,000IU·d-1) or placebo for 12 winter weeks. A URI symptom questionnaire was completed weekly. Serum 25(OH)D concentrations were measured by radio-immunoassay before and after supplementation. We used linear regression to examine the relation between the change in 25(OH)D concentrations during the trial, and the duration and severity of URIs. There were no between-group differences in the frequency, severity, or duration of URIs. Exploratory analyses revealed that in the placebo group only, the change in 25(OH)D concentrations during the trial was highly associated with the duration of URIs (r = -0.90,p < .001), and moderately associated with the severity of URIs (r = -0.65,p = .043). The between-group differences for duration were highly significant. Vitamin D3 supplementation in adolescent swimmers with vitamin D insufficiency did not reduce URI burden. However, larger decreases in serum 25(OH)D concentrations were associated with significantly longer and more severe URI episodes.

Mannose-binding lectin 2 gene polymorphism and susceptibility to upper respiratory tract infection among endurance athletes

The aim of this study was to investigate the influence of mannose-binding lectin 2 (MBL2)-exon-1 gene polymorphisms on upper respiratory tract infection (URTI) incidence among endurance athletes. To this end, 100 healthy elite male athletes participating in the study were classified as either healthy or prone to frequent URTI. Blood samples, DNA isolation, multiplex polymerase chain reaction (PCR) and conventional PCR-RFLP were performed. Genomic DNA was extracted from peripheral leukocytes of whole blood samples using the QIAmp DNA Blood Mini Kit. For comparison of the distribution of genotypes between two groups and for estimating odds ratios (OR) for URTI susceptibility in relation to the MBL2-exon-1 polymorphism, Pearson's chi-square and logistic regression method were used, respectively. The MBL2-exon-1 genotype distribution differed between athletes with URTI and healthy athletes (χ2 = 7.81, p = 0.02). The AO and AO + OO genotypes of MBL2 were observed at a greater frequency in the illness-prone group compared with the healthy group (34.04% vs. 11.32%). In conclusion, findings from this study have identified a potential role of genetic variation in influencing the risk for URTI in athletic populations and single-nucleotide polymorphisms (SNPs) in the MBL2-exon-1 genes were associated with an altered risk profile. These measures may have a predictive value in the identification of individuals who are more likely to experience recurrent infections when exposed to high physical stress in the areas of athletic endeavour.

Interleukin-6 G-174C gene polymorphism and susceptibility to upper respiratory tract infection among endurance athletes

The aim of this study was to investigate the influence of interleukin (IL)-6 gene polymorphisms on upper respiratory tract infection (URTI) incidence. To this end, 100 healthy elite male athletes participating in the study were classified as either healthy or prone to frequent URTI. Blood samples and DNA isolation, multiplex polymerase chain reaction, and Taqman real-time polymerase chain reaction were carried out. Genomic DNA was extracted from peripheral leukocytes of whole blood samples using the QIAmp DNA Blood Mini Kit according to the manufacturer's protocols. For comparison of the distribution of genotypes between the two groups and for estimating odds ratios for URTI susceptibility in relation to the IL-6 polymorphism, Pearson's χ2 and logistic regression methods were used, respectively. The IL-6-174 genotype distribution differed between athletes with URTI and healthy athletes (χ2 = 11.68, p = 0.003). The IL-6 low-expression genotype (CC), relative to the other two genotypes combined (GC + GG), was associated with a tendency for an increased likelihood of frequent URTI (odds ratio: 3.33, 95% confidence interval: 1.40–7.92; p = 0.006). In conclusion, findings from this study have identified a potential role of genetic variation in influencing the risk for URTI in athletic populations and single nucleotide polymorphisms in the IL-6 genes were associated with an altered risk profile. These measures may have a predictive value in the identification of individuals who are more likely to experience recurrent infections when exposed to high physical stress in the areas of athletic endeavor.

Patterns of diseases and preventive measures among domestic hajjis from Central, Saudi Arabia [complete republication

To identify the occurrence of upper respiratory tract infections (URTI), diarrheal diseases and trauma during the Haji season, and the practice of some preventive measures by pilgrims. A cohort study during November and December 2009 among hajjis registered while visiting Primary Health Care Centers of Riyadh, Kingdom of Saudi Arabia to get mandatory meningococcal meningitis vaccination. On return from hajj, hajjis were contacted on telephone to collect information on occurrence of URTI and diarrhea along with other associated activities in Hajj. Out of 1507 hajjis, 54.7% developed symptoms; 97% reported upper respiratory tract symptoms, and 9.3% reported diarrheal symptoms. Those < 40 years of age were more likely to develop an URTI. The incidence of diarrheal diseases or trauma was not statistically associated with age. No statistical difference for educational level was found for U RTI or trauma, but there was a statistically significant difference for diarrheal diseases. There was no statistical difference for nationality in relation to diarrheal diseases and trauma, but there was a statistically significant difference for URTI. There was a statistically significant difference of URTI between those pilgrims who used the face mask most of the time and those who used it sometimes. Upper respiratory tract infections is a common health problem among studied domestic hajjis. Generally, there is room for improvement in the adoption of preventive measures by hajjis; and there is still limited information on the use of facemasks in spite of the fact that using it significantly decreases the risk for URTI.

S123 Increased risk of upper respiratory infection with addition of intermittent bolus-dose vitamin D supplementation to a daily low-dose regimen

Introduction and ObjectivesMeta-analysis of clinical trials of vitamin D supplementation for the prevention of acute respiratory infection (ARI) shows a protective effect in the general population, but there is controversy...

Sugary Foods and the Risk of Upper Respiratory Infections

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Influence of CMV/EBV serostatus on respiratory infection incidence during 4 months of winter training in a student cohort of endurance athletes

The purpose of this study was to examine the influence of previous infection with cytomegalovirus (CMV) or Epstein Barr virus (EBV) on the incidence, severity and duration of upper respiratory tract infections (URTIs) in endurance athletes during a 4-month winter training period. Blood samples were obtained from 236 subjects (166 males and 70 females, aged 18-35years) at the start of the study period. Plasma samples were analysed for CMV and EBV serostatus. Weekly training and daily illness logs were kept for the next 16weeks. With regard to CMV/EBV serostatus, the results indicated that athletes with previous CMV infection (n=58, 25% of cohort) had significantly fewer URTI symptom days (median 2 vs. 4days, p=0.033) during the study period than those with no previous infection (n=178, 75%), whereas positive EBV serostatus (n=197, 84%) had no influence on URTI episode incidence, severity or duration. Moreover, we found that athletes with prior infection of both CMV and EBV (n=50, 21%) had 50% fewer URTI episodes (p=0.04) and symptom days (median 2 vs 8days, p=0.01) than athletes who were seronegative for both CMV and EBV (n=31, 13%). Previous coinfection with CMV and EBV might promote protective immune surveillance to lower the risk of URTI. Further research is required to clarify why previous CMV and EBV infection reduces the incidence of URTI.