Stephen A. Morse

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BACKGROUND AND OBJECTIVES Epidemiologic studies on syphilis have been hampered by the fact that strains of Treponema pallidum subspecies pallidum (T. pallidum), the causative agent of this disease, cannot be differentiated by either protein-based or deoxyribonucleic acid-based methods. Syphilis is endemic in many developing countries and is common in some(More)
Baylisascaris procyonis, a roundworm infection of raccoons, is emerging as an important helminthic zoonosis, principally affecting young children. Raccoons have increasingly become peridomestic animals living in close proximity to human residences. When B. procyonis eggs are ingested by a host other than a raccoon, migration of larvae through tissue, termed(More)
Recently, strains of Neisseria gonorrhoeae have been isolated which are highly resistant to tetracycline (MICs of 16 to 64 micrograms/ml). This resistance was due to the acquisition of the resistance determinant tetM, a transposon-borne determinant initially found in the genus Streptococcus and more recently in Mycoplasma hominis, Ureaplasma urealyticum,(More)
To identify mammalian iron-binding proteins that can serve as iron sources for Streptococcus pyogenes, the group A streptococcus (GAS), we used a plate assay. Ferritin, hemin, hemoglobin, myoglobin, and catalase can support growth of GAS on iron-depleted medium. However, growth was not detected when iron was provided as iron-saturated transferrin or(More)
The utilization of amino acids and other compounds as carbon and energy sources by Legionella pneumophila was examined. Based on the stimulation of oxygen consumption in washed-cell suspensions, glutamate, serine, threonine, and tyrosine were the only amino acids which were utilized as energy sources. Other stimulators of oxygen uptake were lactate,(More)
Haemophilus ducreyi is the causative agent of chancroid, one of the genital ulcerative diseases. H. ducreyi is the major cause of genital ulcer disease in Africa and Southeast Asia and is of increasing concern in the United States. Definitive diagnosis of chancroid requires the isolation and identification of H. ducreyi, but isolation of this organism is(More)
A multiplex polymerase chain reaction (M-PCR) assay for Haemophilus ducreyi, Treponema pallidum, and herpes simplex virus (HSV) was compared with clinical and standard laboratory methods for the diagnosis of genital ulcer disease (GUD) in 105 patients; 36% were human immunodeficiency virus (HIV)-seropositive. Chancroid (80%), syphilis (8%), and genital(More)
BACKGROUND AND OBJECTIVES While genital ulcers are a risk factor in HIV infection, the association of specific agents of genital ulcer disease (GUD) with HIV infection may vary. GOAL To determine the etiology of GUD in HIV-infected and HIV-uninfected men attending sexually transmitted disease (STD) clinics in Durban, Johannesburg, and Cape Town, South(More)
OBJECTIVES To determine demographic and behavioural factors and sexually transmitted infections (STIs) associated with prevalent HIV-1 infection among brothel based and other female sex workers (FSWs) in Chiang Rai, northern Thailand. METHODS Data were collected from questionnaires, physical examinations, and laboratory evaluations on Thai FSWs enrolled(More)