PubMed Health⌕ Search

Biomedical subjects

W H Haas

Publications and source records attributed to W H Haas.

15 recordsLinked to original sources
PubMed1995

Nosocomial transmission of Mycobacterium tuberculosis: role of health care workers in outbreak propagation.

To investigate an outbreak of tuberculosis (TB) among health care workers (HCWs) at a county hospital, all patients with culture-confirmed TB on wards A and B and all HCWs working at least one shift on these wards from January 1991 through March 1992 were studied. Tuberculin skin test conversions occurred in 30% (ward A) and 48% (ward B) of HCWs; 8 developed active TB. Workers exposed for at least one shift to workers or patients with active TB were more likely to have skin test conversion than were workers who were not exposed (ward A exposure relative risk [RR] for workers = 2.8, P = .005, and for patients = 2.2, P > .5; ward B exposure RR for workers = 2.8, P < .001, and for patients = 5.3, P < .001). Underlying conditions and performing charting activities in the nurses' work room were associated with progression to active TB among infected workers. Transmission was facilitated by delays of < or = 2.5 months in treatment of workers with skin test conversion or TB symptoms.

Cross Infection↗
PubMed1993

Amenity retirement migration process: a model and preliminary evidence.

A heuristic model of the retirement migration process was developed and explored using survey data from 586 migrants to western North Carolina. Five distinct subgroups were investigated: those who went from part- to full-time residency; those who thought about not migrating; individuals who migrated, remained in the labor force for a short period, and then retired; people who made two retirement migrations; and destination-selecting versus destination-specific migrants.

Adult↗
PubMed1993

Cervical lymphadenitis in a child caused by a previously unknown mycobacterium.

Acid-fast bacilli were isolated from lymph nodes of an immunocompetent child presenting with unilateral cervical lymphadenitis. The slowly growing mycobacterium could not be identified by traditional methods. Direct sequencing of the enzymatically amplified 16S rRNA gene revealed a unique sequence belonging to a previously unrecognized mycobacterium. Direct 16S rDNA sequencing enables definitive identification of mycobacterial isolates. The method is useful for rapid recognition of previously unrecognized pathogens.

Base Sequence↗
PubMed1993

Nosocomial outbreak of tuberculosis in a renal transplant unit: application of a new technique for restriction fragment length polymorphism analysis of Mycobacterium tuberculosis isolates.

From January 1990 through February 1991, tuberculosis (TB) developed in 10 renal transplant (RT) patients at one hospital; 5 patients died. Possible nosocomial transmission was investigated. Mycobacterium tuberculosis isolates were compared by restriction fragment length polymorphism (RFLP) by a polymerase chain reaction method. The source case occurred in an RT patient (source) who had posttransplant exposure to TB at another hospital. The source patient was rehospitalized on the RT unit; diagnosis of TB and thus isolation precautions were delayed. Epidemiologic and RFLP analysis showed transmission from the source to 5 RT patients and 1 human immunodeficiency virus-infected patient. M. tuberculosis isolates from 4 RT patients had other RFLP patterns. The median incubation period for TB in RT patients was 7.5 weeks (range, 5-11). Bronchoscopy and intubation of the source patient and inadequate ventilation on the RT unit possibly increased transmission. Early detection of TB and effective isolation are essential to prevent nosocomial transmission.

Adult↗
PubMed1993

Mixed-linker polymerase chain reaction: a new method for rapid fingerprinting of isolates of the Mycobacterium tuberculosis complex.

Rapid recognition of multidrug-resistant strains of Mycobacterium tuberculosis is a desirable goal for treatment of patients and protection of health care workers. DNA fingerprints produced with the insertion sequence IS6110 generate restriction fragment length polymorphism (RFLP) patterns that reliably identify M. tuberculosis complex strains. This report describes a rapid technique for RFLP typing using the polymerase chain reaction. The method uses one primer specific for IS6110 and a second primer complementary to a linker ligated to the restricted genomic DNA. In one strand the linker contains uracil in place of thymidine, and specific amplification is obtained by elimination of this strand with uracil N-glycosylase. Mixed-linker fingerprinting clearly differentiated multidrug-resistant isolates from 12 outbreaks and unambiguously assigned them to 26 RFLP groups.

Base Sequence↗
PubMed1986

The relationship of pulsed, continuous, and warble extended-high frequency thresholds.

The relationship among pulsed, continuous and warble tone 10, 12, 14, and 16 kHz thresholds of six normal hearing young adults was studied. It was found that pulsed and continuous tones elicited essentially equivalent thresholds at all frequencies tested. Warble tone thresholds were markedly better than unmodulated thresholds at 14 and 16 kHz. This threshold discrepancy is believed to be attributable to hearing the lowest frequency components of the warble tone when a sloping audiometric configuration exists. The audiologist is cautioned against using warble tones in extended-high frequency testing.

Adult↗
PubMed1980

Characteristics of family practitioners with large geriatric practices.

Little has been reported on the characteristics of physicians presently serving the health needs of the elderly. In this report, generated from a survey of Florida family practitioners, physicians and with large geriatric practices are compared to physicians with practices composed primarily of younger patients. Family physicians with large geriatric practices are older, and treat more chronic disease than do their peers. However, they consult the same professional journals and texts in caring for their patients, refer patients to specialists at the same rate, and have the same office facilities as do their colleagues who treat chiefly younger patients. The family physician with a large geriatric case load is less likely to have a predominantly outpatient practice and more likely to be involved with hospitalized patients. Data from the census and health manpower studies suggest that family physicians will care for substantial number of elderly patients in the future. Continuing education which addresses issues in geriatrics may help to attain optimal health care for the elderly.

Age Factors↗
PubMed1978

Discrimination of speech intensity differences via vibrotactile stimulation.

This study investigated vibrotactile difference limen judgments for intensity using certain speech signals as stimuli. The variables under investigation were those of stimulus presentation level, direction of intensity increment or decrement within each paired-comparison stimulus complex, and the spectral composition of the speech signals. The results indicate that the level of stimulus presentation did not affect difference limen decisions among any of the sensation levels utilized. The largest most consistent effect upon difference limen judgments was in the direction of intensity change. The difference limen judgments were smaller when the second stimulus of the pair was of less intensity than the first. There was no effect upon difference limen decision as the result of stimuli having different spectral compositions.

Acoustics↗