14 Herpesviruses
Large, enveloped, double-stranded DNA viruses Eight HHVs cause a range of diseases HERPESVIRUSES: GROUP CHARACTERISTICS VIROLOGY All herpesviruses are morphologically similar, with an overall size of 180 to 200 nm….
37 Spirochetes
BACTERIOLOGY MORPHOLOGY AND STRUCTURE The spiral morphology of spirochetes (Figure 37–1) is produced by a flexible, peptidoglycan cell wall around which several axial fibrils are wound. The cell wall and…
16 Arthropod-Borne and Other Zoonotic Viruses
ARTHROPOD-BORNE ZOONOTIC ARBOVIRUSES VIROLOGY In most cases, the zoonotic viruses were first named after the place of initial isolation (eg, St. Louis encephalitis) or after the disease produced (eg, yellow…
55 Tissue Nematodes
TOXOCARA TOXOCARA CANIS: PARASITOLOGY AND LIFE CYCLE (FIGURE 55–1) FIGURE 55–1. Life cycle of Toxocara canis. (Reproduced with permission from Roberts RL, Janovy J, Nadler S: Foundations of Parasitology, 9th…
56 Cestodes
Clinical effects depend on whether humans are definitive hosts or intermediate hosts Tissue cysts, not intestinal worms, cause serious disease PARASITOLOGY MORPHOLOGY Like all helminths, tapeworms lack vascular and respiratory…
53 Sarcomastigophora—The Flagellates
Found in flora of vertebrates These organisms are elongated or oval and typically measure 10 to 20 μm in length. They often possess a rudimentary cytostome (mouth aperture) and organelles,…
27 Mycobacteria
BACTERIOLOGY STRUCTURE The mycobacteria are slim, poorly staining bacilli, which demonstrate the property of acid-fastness. They are nonmotile, obligate aerobes that do not form spores. The cell wall contains peptidoglycan…
30 Neisseria
FIGURE 30–1. Neisseria gonorrhoeae. Gram stain of urethral exudate. Note the many pairs of Gram-negative bean-shaped diplococci (arrow) collected in polymorphonuclear neutrophils (PMNs) and free in the purulent material. The…
23 Antibacterial Agents and Resistance
Definitions • Antibiotics—antimicrobials of microbial origin, most of which are produced by fungi or by bacteria of the genus Streptomyces. • Antimicrobials—substances used in the treatment of infectious diseases. In…
4 Principles of Laboratory Diagnosis of Infectious Diseases
FIGURE 4–1. Specimens for the diagnosis of infection. A. Direct specimen. The pathogen is localized in an otherwise sterile site, and a barrier such as the skin must be passed…
