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Biomedical subjects

J Owen Hendley

Publications and source records attributed to J Owen Hendley.

15 recordsLinked to original sources
PubMed2006

Picornavirus infections in children diagnosed by RT-PCR during longitudinal surveillance with weekly sampling: Association with symptomatic illness and effect of season.

RT-PCR is more sensitive for rhinovirus detection than cell culture, but healthy controls are frequently rhinovirus (or picornavirus) positive in cross-sectional studies. Fifteen healthy children were followed over at least three seasons of the year with weekly sampling of nasal/nasopharyngeal secretion for RT-PCR testing for picornavirus and daily recording of respiratory symptoms. One sample positive for picornavirus was diagnosed as an infection; consecutive positive weekly samples constituted a single infection. Picornavirus illness was diagnosed if RNA was detected 7 days prior through 21 days after onset. One hundred fifty-five (21%) of 740 weekly samples were picornavirus positive and associated with illness; 37(5%) positives were not associated with illness (P = 0.001). The 192 positive samples occurred in 121 infections, 74 with a single positive and 47 with "runs" of positives in two or more consecutive samples. Forty five (96%) of the 47 runs comprised 2 or 3 consecutive positives. Ninety six (52%) of 185 reported illnesses during 235 child-months were picornavirus positive (0.4/child-month); 25 infections were asymptomatic (0.11/child-month). The infection rate was highest in fall (0.66/child-month); the winter rate (0.44/child-month) was similar to that in spring (0.5) and summer (0.43). Picornavirus infections in healthy children were common (0.51/child-month), episodic, and usually associated with brief illness; one fifth of infections were asymptomatic. The infection rate was highest in fall; infections in winter occurred at the same rate as in spring and summer.

Carrier State↗
PubMed2005

Virucidal hand treatments for prevention of rhinovirus infection.

Rhinovirus infections are associated with substantial morbidity and economic cost. The available common cold remedies are of limited utility and specific antiviral approaches have been unsuccessful. Viral contamination of the hands appears to play an important role in the transmission of rhinovirus from person-to-person. Interruption of this step in transmission presents a potential target for intervention. Initial studies demonstrated that the common cold could be prevented by treatment of hands with iodine. Inactivation of the rhinoviruses by acid is well known and a survey of organic acids considered safe for consumer use revealed that salicylic acid and pyroglutamic acid have potent virucidal activity for the rhinoviruses that persists for several hours after application to the hands. A subsequent evaluation in human volunteers confirmed the prevention of rhinovirus infections by these acids and suggested that these agents have promise as cosmetically acceptable virucidal agents for interruption of the transmission of these infections.

Antiviral Agents↗
PubMed2005

Weekly point prevalence of Streptococcus pneumoniae, Hemophilus influenzae and Moraxella catarrhalis in the upper airways of normal young children: effect of respiratory illness and season.

The aim was to determine the effect of respiratory illness and season on carriage rates in the upper airways of Streptococcus pneumoniae, Hemophilus influenzae and Moraxella catarrhalis in normal children. Sixteen healthy children, 1-10 years old, amenable to weekly sampling were followed longitudinally for at least three seasons of the year. Respiratory symptoms were recorded daily; weekly nasal aspirate/wash samples were cultured on selective agars. Urea concentration in samples was used to define dilution of secretion. 68% of 950 samples were culture positive; 44% of positives had two or all three species. Each species was detected in about one third of samples. Bacteria were detected in 76% of samples during illness vs. 65% during wellness (p=0.004). Seasonal carriage rates varied from 56% in summer and fall to 85% in winter. There was a strong inverse correlation between dilution of secretion and bacterial detection rate in illness and wellness aspirate samples during the four seasons (r=-0.82, p=0.01). Detection of bacteria varied with the amount of secretion in the sample. This variation accounts for the apparent differences in bacterial carriage during illness vs. wellness and during different seasons.

Carrier State↗
PubMed2004

Viral titers in nasal lining fluid compared to viral titers in nasal washes during experimental rhinovirus infection.

BACKGROUND: The concentration of rhinovirus in nasal wash specimens from infected volunteers peaks at 48-72 h after inoculation. The volume of expelled nasal fluid peaks at the same time, raising the question of whether the viral concentration in nasal wash reflects viral replication in nasal cells or merely the production of an increased volume of nasal fluid during a cold. OBJECTIVES: To determine the amount of rhinovirus in nasal lining fluid during colds before the nasal fluid has been diluted in a nasal wash. STUDY DESIGN: Rhinovirus titers were determined in nasal wash specimens collected daily for five days from 14 subjects with type16 rhinovirus infection. The urea concentration in nasal lining fluid equals that in blood. By determining the urea concentration in a nasal wash and comparing it to the urea concentration in blood from the same subject, it was possible to determine the amount of dilution of the nasal lining fluid. The dilution factor (reciprocal of the dilution) was then used to calculate the viral concentration in undiluted nasal lining fluid. RESULTS: The dilution factor in 70 nasal washes varied from 5 to 64. The viral GMTs (+S.E.) in nasal washes were 1.79 (+0.3) TCID(50)/ml at 24 h, 3.11 (+0.15) at 48 h, and 2.61 (+0.3) at 72 h. The viral GMTs in nasal lining fluid, based on urea adjusted values, paralleled those in nasal washes but were approximately one log higher. Virus concentrations returned to near baseline values by day 5. CONCLUSIONS: The temporal pattern of rhinovirus shedding observed in nasal wash specimens, with a peak in virus concentration at 48-72 h after infection, is a true indication of virus production in nasal cells and not an artifact of the increased amount of nasal fluid produced during the early phase of a cold.

Common Cold↗
PubMed2004

Sensitivity of a rapid antigen detection test for group A streptococci in a private pediatric office setting: answering the Red Book's request for validation.

In the office laboratory of our private practice, the sensitivity of a single rapid antigen detection (RAD) test for group A streptococci (compared with backup throat culture) was examined over 3 winter periods. When cultures were held only 24 hours, the sensitivity was 92%; in the second period, when cultures were held to 48 hours, the sensitivity declined significantly to 86%; when the cultures were read without knowledge of the RAD test result, the sensitivity was 85%. As the Red Book Committee has suggested, physician office laboratories should validate the sensitivity of their RAD test against culture onto blood agar before abandoning the backup throat culture.

Antigens, Bacterial↗
PubMed2003

Symptom severity patterns in experimental common colds and their usefulness in timing onset of illness in natural colds.

Mean total symptom severity scores for subjects with experimental rhinovirus colds peak 48 h after viral inoculation. Also, total symptom scores for natural rhinovirus and nonrhinovirus colds peaked on day 2 of illness in a long-term, noncompensated epidemiology study. In contrast, the mean total symptom scores for compensated patients receiving placebo in natural cold treatment trials peaked on day 1. Comparisons by day indicated that scores for symptoms reported as occurring on day 1 in the natural cold treatment trials corresponded with experimental cold scores for symptoms reported 48 h after viral inoculation. Comparisons of frequency and cumulative distribution scores for the 2 groups indicated that natural colds in the treatment trials were of longer duration than reported. A mean total symptom severity score of <or=7 would capture 95% of experimental colds 24 h after inoculation while excluding 30.5% of natural colds on day 1 of illness. Histories given by compensated patients in natural cold treatment trials are inaccurate.

Common Cold↗
PubMed2003

Eradication of resident bacteria of normal human skin by antimicrobial ointment.

The application of a topical triple-antibiotic ointment (containing neomycin, polymyxin, and bacitracin) eradicated resident bacteria through 25 layers of the stratum corneum and prevented repopulation of bacteria overnight but not at 1 week. Through 15 layers, mupirocin had some effect, whereas a double-antibiotic ointment had none. The reservoir of resident bacteria in the sebaceous glands is not affected by a topical antibiotic.

Administration, Cutaneous↗
PubMed2003

Otitis media. A scholarly review of the evidence.

Antibiotic therapy remains the treatment of choice for otitis media in most countries despite persuasive evidence that antibiotic therapy provides limited clinical benefit and promotes bacterial resistance. Meta-analysis of randomized, placebo-controlled trials demonstrated that antibiotics increased resolution at 1 week by only 13%. Amoxicillin remains as effective as any other antibiotic, despite increasing resistance to amoxicillin among the major bacterial pathogens. Immediate antibiotic treatment has been shown to reduce the duration of symptoms by 1 day but not until after the first 24 hours when symptoms were already improving. A delayed prescribing strategy is currently utilized in most children for management of acute otitis media in the Netherlands; this method is now being evaluated elsewhere. Antibiotic therapy is delayed for 48-72 hours after diagnosis; thereafter, antibiotics are initiated only if symptoms persist or worsen. In 2 studies utilizing this strategy (England and the United States), only 24-30% of the patients in the delayed treatment group initiated antibiotic therapy; a majority of parents of children in the delayed group were satisfied with their child's treatment. Treatment of bacterial otitis media ("pus drum") with high dose amoxicillin (80-100 mg/kg/kd) is recommmended; for acute otitis media without bulging, watchful waiting with a delayed prescribing strategy and treatment of pain is preferred. Yearly administration of the influenza vaccine and/or treatment of influenza with an antiviral (oseltamivir) can significantly decrease the incidence of acute otitis media during influenza season. Although pneumococcal vaccination effectively reduces the incidence of acute otitis media due to vaccine-related serotypes, there is a significant increase in the number of episodes of acute otitis media due to other serotypes of S. pneumoniae such that the overall incidence of acute otitis media is reduced only minimally by pneumoccocal vaccine. The careful use of strict diagnostic criteria coupled with judicious use of antibiotic therapy will direct antibiotic treatment to only those patients likely to benefit.

Acetamides↗
PubMed2002

Combined antiviral-antimediator treatment for the common cold.

A randomized, controlled, double-masked clinical trial was conducted with a combination antiviral-antimediator treatment for experimental rhinovirus colds. In all, 150 healthy men and women (aged 18-51 years) were randomly assigned to 1 of 3 groups: intranasal interferon (IFN)-alpha2b (6 x 10(6) U every 12 h x 3) plus oral chlorpheniramine (12 mg extended release) and ibuprofen (400 mg) every 12 h for 4.5 days (n=59 subjects); intranasal placebo plus oral chlorpheniramine and ibuprofen (n=61 subjects); or intranasal and oral placebos (n=30 subjects). Treatment was started 24 h after intranasal viral challenge. During the 4.5 days of treatment with IFN-alpha2b, chlorpheniramine, and ibuprofen, the daily mean total symptom score was reduced by 33%-73%, compared with placebo. Treatment reduced the severity of rhinorrhea, sneezing, nasal obstruction, sore throat, cough, and headache and reduced nasal mucus production, nasal tissue use, and virus concentrations in nasal secretions. IFN-alpha2b added to the effectiveness of chlorpheniramine and ibuprofen and was well tolerated.

Adolescent↗
PubMed2002

Cross-linked fibrin in the nasal fluid of patients with the common cold.

To determine whether adherent material found on the walls of the paranasal sinuses during common colds might be fibrin clot, we examined the nasal fluid (a surrogate for sinus secretion) of 11 young adults with experimentally induced rhinovirus colds and that of 4 control subjects for the presence of fibrin. The mean concentration (+/- the standard error) of insoluble fibrin (measured as D-dimer) in subjects with rhinovirus colds increased from a baseline level of 0.8+/-0.4 microgram/mL to a peak of 2.4+/-0.7 microgram/mL (P=.0008) on day 4 after inoculation of the virus, but the fibrin concentration remained at baseline levels in the 4 uninfected control subjects.

Adult↗
PubMed2002

Clonal diversity of Escherichia coli colonizing stools and urinary tracts of young girls.

Intestinal carriage of Escherichia coli in prepubertal girls without a history of urinary tract infection was examined by collecting weekly stools and periurethral and urine samples over 3 to 4 weeks of study. Dominant and minor clones were defined by grouping 28 E. coli isolates into clonal types. Multiple enteric clones of E. coli, which changed week to week, were found in the 13 girls during the study (median, 3 clones/girl; range, 1 to 16 clones/girl). Dominance of an enteric clone did not predict persistence in the stool. In only 10 (34%) of the 29 episodes in which a dominant clone present in one weekly sample could have been detected the following week did it persist as the dominant clone in the next weekly sample. In 5 (17%) of the 29 episodes, a dominant clone found in one weekly sample was classified as a minor clone the next week. Both dominant and minor clones were observed to colonize the urinary tract. However, when colonization of the periurethra or bladder urine occurred, it was brief and often did not reflect the dominant stool flora from the same week. In fact, in only 40% of episodes was a clone that was detected either on the periurethra or in the urine also recovered from the stool the same week. Our findings suggest that the intestinal flora of healthy girls is multiclonal with frequent fluctuations in composition.

Bacteriuria↗
PubMed2002

Viral respiratory infection in schoolchildren: effects on middle ear pressure.

OBJECTIVE: To evaluate the effect of uncomplicated viral respiratory infections (colds) on middle ear pressure in healthy school-aged children. METHODS: Children (ages 2-12) with normal tympanograms before onset of illness had bilateral tympanometry daily except weekends for 2 weeks after the onset of a cold. Nasopharyngeal secretion obtained at onset of illness was cultured for bacterial pathogens of otitis media using selective agars and tested for rhinovirus, coronavirus, respiratory syncytial virus, influenza A and B, and parainfluenza 1-3 by reverse transcriptase polymerase chain reaction technology. Tympanometry was designated as abnormal with peak pressure of < or =-100 daPa or > or =50 daPa and/or a compliance peak of < 0.2 cm(3). RESULTS: Eighty-six colds were studied, 82 in schoolchildren (5-12 years old) and 4 in 2- to 3-year-olds. Abnormal negative middle ear pressure occurred at least once during the 2 weeks after onset in 57 (66%) of the 86 colds. Tympanometry was abnormal in the first week after onset in 50 (88%) of the 57 colds and was abnormal on a single day in 17 (30%) of the 57. The middle ear pressure abnormalities were intermittent and shifted from one ear to the other ear from day to day. Reverse transcriptase polymerase chain reaction was positive for a respiratory virus in 56 (65%) of the 86 illnesses. Rhinovirus was found in 48% and respiratory syncytial virus in 14%. Pathogenic bacteria (Streptococcus pneumoniae, Haemophilus influenzae, or Moraxella catarrhalis) were detected in nasopharyngeal secretion in 29 (34%) of the 86 colds; the bacteria were in high titer (> or =10(3) cfu/mL) in 26 of the 29 positive specimens. None developed illness that required a visit to a physician. Age, detection of a respiratory virus, and presence of bacterial pathogen in the nasopharyngeal secretion had a negligible effect on the occurrence of abnormal tympanometry. Occurrence of negative middle ear pressure in winter-spring colds was significantly greater than in fall colds for unexplained reasons. CONCLUSIONS: Transient negative middle ear pressure occurred in two thirds of uncomplicated colds in healthy children. This negative pressure, which may facilitate secondary viral or bacterial otitis media, seems to result from viral infection of the nasopharynx and distal tube causing bilateral eustachian tube dysfunction. Tympanometry provides an objective measure of the potential beneficial effects of investigational treatments on the risk of eustachian tube dysfunction/otitis media.

Acoustic Impedance Tests↗
PubMedDate not supplied

Nasopharyngeal reservoir of bacterial otitis media and sinusitis pathogens in adults during wellness and viral respiratory illness.

BACKGROUND: The carriage rate of pathogenic bacteria in the nasopharynx (NP) was determined using three separate techniques for obtaining samples. METHODS: The NP of 99 healthy adults was sampled with (1) nasal swab, (2) oral swab, and (3) nasal aspiration; 49 adults with common cold were sampled with an oral swab and nasal aspiration. Three selective agars were used to detect Streptococcus pneumoniae, Hemophilus influenzae, and Moraxella catarrhalis. RESULTS: Seventy-three percent of healthy adults and 74% of cold sufferers had at least one pathogen detected in the NP. Detection rates were 65% (oral NP swab), 38% (catheter aspiration), and 28% (nasal swab; p < 0.001). Carriage rates for S. pneumoniae, M. catarrhalis, and H. influenzae were 45, 33, and 30%, respectively. Both a nasal and an oral sample were required for optimal detection. CONCLUSION: Bacterial pathogens were present in the NP of three-quarters of adults during wellness and during colds.

Adult↗