BRUCELLA BACTERIOLOGY Brucella species are small, coccobacillary, Gram-negative rods that morphologically resemble Haemophilus and Bordetella. They are nonmotile, non-acid-fast, and non-spore-forming. The cells have a typical Gram-negative structure, and the…
SUPERFICIAL FUNGI Dermatophytes Dermatophytoses are superficial infections of the skin and its appendages, commonly known as ringworm (Figure 45–1), athlete’s foot, and jock itch. They are caused by species of…
heart is like wax; it is melted in the midst of my bowels. —The Bible: Psalms 22:14 This group of curved Gram-negative rods includes Vibrio cholerae, the cause of cholera,…
PAPILLOMAVIRUSES VIROLOGY Papillomaviruses are small, naked capsid (unenveloped), double-stranded, circular DNA viruses exhibiting cubic (icosahedral) symmetry of 55 nm in diameter (Figure 19–1). The icosahedral capsid comprises two capsid (structural)…
BACTERIOLOGY STRUCTURE Rickettsiae are small coccobacilli (Figure 40–1) which measure no more than 0.3 to 0.5 μm. Although the Gram reaction is negative, rickettsiae take the usual bacterial stains poorly…
Microbes gain access from the environment Skin is a major protective barrier For the internal surfaces a viscous mucin secreted by goblet cells protects the epithelium lining of the respiratory…
FIGURE 1–1. Death rates for infectious disease in the United States in the 20th century. Note the steady decline in death rates related to the introduction of public health, immunization,…
FIGURE 43–1. Fungi system view. Localized disease (left) is caused by local trauma or the superficial invasion of flora resident on the oropharyngeal (thrush), gastrointestinal, or vaginal mucosa. Systemic disease…
BACTERIOLOGY Pseudomonas aeruginosa is an aerobic, motile, Gram-negative rod that is slimmer and more pale staining than members of the Enterobacteriaceae. Its most striking bacteriologic feature is the production of…
TABLE 20–2 Unconventional Virus (Prion) Diseasesa TABLE 20–3 Biologic and Physical Properties of Prions • Chronic progressive pathology without remission or recovery • No inflammatory response • No alteration in…
