Shigellosis , infection by Shigella species , is acute invasive enteric infection clinically manifested by diarrhea that is often bloody. The term dysentery describes a syndrome of bloody diarrhea with fever, abdominal cramps, rectal pain, and mucoid stools. Bacillary dysentery…
Salmonellosis is a common and widely distributed food-borne disease that is a global major public health problem affecting millions of individuals and resulting in significant mortality. Salmonellae live in the intestinal tracts of warm- and cold-blooded animals. Some species are…
Pertussis is an acute respiratory tract infection; the term pertussis means “intense cough” and is preferable to whooping cough, because most infected individuals do not “whoop.” Etiology Bordetella pertussis is the cause of epidemic pertussis and the usual cause of…
Moraxella catarrhalis is an unencapsulated gram-negative diplococcus and is a human-specific pathogen that colonizes the respiratory tract beginning in infancy. Patterns of colonization and infection with M. catarrhalis are changing in countries where pneumococcal conjugate vaccines are used widely. The…
Chancroid is a sexually transmitted disease characterized by painful genital ulceration and inguinal lymphadenopathy. Etiology and Epidemiology Chancroid is caused by Haemophilus ducreyi, a fastidious gram-negative bacillus. It is prevalent in many developing countries but occurs sporadically in the developed…
Effective vaccines to prevent Haemophilus influenzae type b (Hib) disease, introduced in the United States and most other countries, have resulted in a dramatic decrease in the incidence of infections caused by this organism. However, mortality and morbidity from Hib…
Kingella kingae is being increasingly recognized as the most common etiology of septic arthritis, osteomyelitis, and spondylodiscitis in young children. Etiology Kingella kingae is a fastidious, facultative anaerobic, β-hemolytic member of the Neisseriaceae family that appears as pairs or short…
Neisseria gonorrhoeae is the causative agent of gonorrhea , an infection of the genitourinary tract mucous membranes and of the mucosa of the rectum, oropharynx, and conjunctiva. Gonorrhea transmitted by sexual contact or perinatally is second only to chlamydial infections…
Neisseria meningitidis (the meningococcus) is a commensal of the human nasopharynx in approximately 10% of the population and rarely enters the bloodstream to cause devastating invasive disease such as meningitis and meningococcal septicemia (meningococcemia). Although a rare endemic disease in…
A number of Nocardia species have been identified as the source of both local and disseminated disease in children and adults. These organisms are primarily opportunistic pathogens infecting immunocompromised persons. Infection caused by these bacteria is termed nocardiosis , which…