Search PubMed⌕ Search

Biomedical subjects

C B Hall

Publications and source records attributed to C B Hall.

At least 181 records · Page 10Linked to original sources
PubMed1975

Nosocomial influenza infection as a cause of intercurrent fevers in infants.

All patients on an infants' ward manifesting intercurrent fevers were studied for viral and bacterial etiology during a community outbreak of influenza A. During a one-month period, of 29 infants admitted to the ward, 17 were hospitalized for seven or more days. Intercurrent fever complicated the course of 13 (76%) of these 17 infants. Nosocomially acquired influenza A infection was found in 13 infants. Two of these also contracted a dual infection with influenza B. The fever lasted an average of 2.7 days with a peak of 38.2 to 39.8 C. Initial white blood cell counts tended to by high and shifted to the left. These infants appeared to be at high risk for developing lower respiratory tract disease. Seven of the 12 had infiltrates on chest X-ray, and five subsequently developed a secondary bacterial pneumonia. These infants tended to be young, five were under 6 months, and all but one had underlying cardiorespiratory disease. They also appeared to have prolonge shedding of influenza virus from their nasal secretions. Six of seven shed the virus for 7 or 21 days.

Animals↗
PubMed1975

Live attenuated influenza virus vaccine trial in children.

Thirty-four children received intranasally a live attenuated influenza A virus vaccine, and were then followed for six months to evaluate the vaccine safety, immunogenicity, and efficacy. All but one of the 31 children with hemagglutination inhibition (HI) titers less than 64 before inoculation responded with at least a four-fold rise in antibody titer to a single dose of vaccine. One child required two doses. Seven (21%) of the vaccinees also responded with production of nasal neutralizing antibody. The vaccine was well tolerated with few clinical reactions. Two vaccinees developed fever possibly attributable to the vaccine. No transmission of the vaccine virus to any of the 25 unvaccinated contact children was demonstrable. Five months after this vaccine trial an influenza epidemic due to a heterologous influenza A strain occurred in the community. During this outbreak acute febrile and/or respiratory illness occurred in 12 or 52% of the contact controls, and in six or 19% of the vaccinees. In two of these six vaccinees, influenza A infection was confirmed by at least a four-fold increase in HI titer. This study suggests this study suggests that this vaccine is safe, easily administered, highly immunogenic in children, and is protective against a heterologous strain epidemic in the community.

Adolescent↗
PubMedDate not supplied

Influenza surveillance in community-dwelling elderly compared with children.

BACKGROUND: Acute respiratory illnesses (ARIs) are the leading cause of medical visits for community-dwelling patients of all ages, but virologic and clinical descriptions of these illnesses in older adults are infrequent. OBJECTIVES: To determine the feasibility of influenza surveillance in a population of community-dwelling elderly, to compare the patterns of influenza infection in elderly persons with that observed in young populations in which surveillance is usually conducted, and to describe the clinical presentation of influenza infection in elderly outpatients who seek medical attention for ARI. DESIGN: Prospective clinical and viral surveillance of ARIs among ambulatory patients during 3 consecutive winter seasons. SETTING: Nine internal medicine and 3 pediatric practices in Upstate New York in cooperation with the Medicare Influenza Vaccine Demonstration Project. PATIENTS: Elderly (n=808) and pediatric (n=2080) outpatients with ARI office visits. MEASUREMENTS: Frequency of influenza and other respiratory virus isolates and clinical profile of influenza among older adults and children with ARIs. RESULTS: Influenza virus was the viral agent recovered most often from specimens obtained from patients in both age groups with ARI symptoms, especially those with fever. Influenza accounted for 11% of ARIs in adults (87 isolates) and 20% in children (408 isolates). At the initial illness visit, influenza infection was equally common in elderly individuals with or without underlying cardiopulmonary conditions. Lower respiratory tract signs occurred in 13% of the adults and in 7% of the children with influenza documented by laboratory studies. Other respiratory viruses were recovered from specimens obtained from 20 adults and from 259 children. CONCLUSIONS: Viruses are important agents of ARIs in elderly outpatients. Children and older adults experience similar patterns of influenza infection and other epidemic respiratory pathogens, such as parainfluenza and respiratory syncytial viruses. Viral identification is feasible in older adults seen in physicians' offices and may contribute to improved measures of effects of influenza and other respiratory viruses on ARIs.

Acute Disease↗
PubMedDate not supplied

A change point model for estimating the onset of cognitive decline in preclinical Alzheimer's disease.

Dementia is characterized by accelerated cognitive decline before and after diagnosis as compared to normal ageing. Determining the time at which that rate of decline begins to accelerate in persons who will develop dementia is important both in describing the natural history of the disease process and in identifying the optimal time window for which treatments might be useful. We model that time at which the rate of decline begins to accelerate in persons who develop dementia relative to those who do not by using a change point in a mixed linear model. A profile likelihood method is proposed to draw inferences about the change point. The method is applied to data from the Bronx Ageing Study, a cohort study of 488 initially non-demented community-dwelling elderly individuals who have been examined at approximately 12-month intervals over 15 years. Cognitive function was measured using the Buschke Selective Reminding test, a memory test with high reliability and known discriminative validity for detecting dementia. We found that the rate of cognitive decline as measured by this test in this cohort increases on average 5.1 years before the diagnosis of dementia.

Aged↗
PubMedDate not supplied

Validation of dual x-ray absorptiometry for body-composition assessment of rats exposed to dietary stressors.

Evidence of the validity and accuracy of dual x-ray absorptiometry (DXA) to measure soft-tissue composition of laboratory rats with altered body composition associated with nutritional perturbations is lacking. We compared DXA determinations made in prone and supine positions with measurements of chemical composition of 49 male, weanling Sprague-Dawley rats that were fed the basal AIN-93 growth diet, were fed the basal diet modified to contain 30% fat, were fasted for 2 d, were limit fed 6 g of the basal diet daily for 1 wk, or were treated with furosemide (10 mg/kg intraperitoneally 2 h before DXA). DXA produced similar estimates of body mass and soft-tissue composition in the prone and supine positions. DXA estimates of body composition were significantly correlated with reference composition values (R(2) = 0.371-0.999). DXA discriminated treatment effects on body mass, fat-free and bone-free mass, fat mass, and body fatness; it significantly underestimated body mass (1% to 2%) and fat-free and bone-free mass (3%) and significantly overestimated fat mass and body fatness (3% to 25%). The greatest errors occurred in treatment groups in which body mass was diminished and body hydration was decreased. These findings suggest that DXA can determine small changes in fat-free, bone-free mass in response to obesity and weight loss. Errors in DXA determination of fat mass and body fatness associated with extra corporeal fluid and dehydration indicate the need for revision of calculation algorithms for soft-tissue determination.

Absorptiometry, Photon↗
PubMedDate not supplied

Nosocomial viral infections: I. Epidemiology and significance.

Viral illnesses in Strong Memorial Hospital were monitored over a 17-month period. Using criteria based primarily on the incubation periods for a number of common virus infections, the infections we found were classified as hospital- or community-acquired. Hospital-acquired viral infections occurred on most hospital services; the majority of infections occurred on the pediatric and psychiatric services. Infections due to herpesviruses were seen more frequently in a group of patients aged 14 years or older, while infections in patients aged three years or younger were more likely to be due to respiratory syncytial virus, influenzavirus, adenovirus, or parainfluenza virus. Patients with nosocomial infections due to viruses were hospitalized an average of 9.3 days longer than uninfected controls; thus nosocomial viral infections result in increased costs of hospitalization.

Adenoviridae Infections↗
PubMedDate not supplied

Nosocomial viral infections: II. Guidelines for prevention and control of respiratory viruses, herpesviruses, and hepatitis viruses.

This article reviews the most likely mechanisms of transmission of the commonly encountered respiratory viruses (influenza, respiratory syncytial virus, parainfluenza, rhinovirus), herpesviruses, and hepatitis viruses, and presents the guidelines used currently for prevention and control that are in use at Strong Memorial Hospital.

Cross Infection↗