History The first epidemic of whooping cough was described in 1578 by de Baillou, who wrote the following: “The lung is so irritated that, in its attempt by every effort to cast forth the cause of the trouble, it can neither admit breath nor easily give it forth again. The sick person seems to swell up, and, as if about to strangle, holds his breath clinging…
First discovered in 1894 in Hong Kong by Alexandre Yersin and Shibasaburo Kitasato, the genus Yersinia currently includes 18 species. Of these, only three have been identified as human pathogens: Y. pestis, Y. pseudotuberculosis, and Y. enterocolitica. While Y. pestis causes plague and is responsible for one of the greatest calamities in human history, the Black Death of mid-14th century Europe, infections from Y. pseudotuberculosis and…
The genus Yersinia includes at least 19 described species, of which 3 are important human pathogens. Yersinia enterocolitica and Yersinia pseudotuberculosis are enteric pathogens usually acquired through ingestion of contaminated food or water. The third species, Yersinia pestis, causes plague. Although closely related to Y. pseudotuberculosis, Y. pestis has undergone a marked evolutionary shift to become a vector-borne pathogen capable of achieving the high levels of…
Pasteurella are gram-negative coccobacilli that inhabit the oral cavity and gastrointestinal tract of many animals and cause various infectious problems, including septicemia and pneumonia. In humans infection is most often caused by dog and cat bites, resulting in cellulitis, subcutaneous abscesses, and a number of other syndromes. Bacteria belonging to the genus Pasteurella were first isolated from birds with cholera in 1878; they were characterized 2…
Francisella tularensis is a gram-negative pathogen primarily of animals and occasionally of humans. The disease is now recognized as tularemia in most areas of the world, but it has been called rabbit fever, deer fly fever, Francis disease, and market men's disease in the United States; wild hare disease (yato-byo) and Ohara disease in Japan; and water-rat trappers’ disease in Russia. Tularemia continues to be responsible…
Brucellosis is the most frequently encountered worldwide zoonotic disease, which can be acquired from sheep, goat, cattle, swine, and other animals and transmitted to humans. Each year half a million new human brucellosis cases cause serious consequences on health and socioeconomic issues, particularly in underdeveloped countries. The disease is under control in developed countries. The disease is frequently transmitted from unsterilized milk and dairy products, and…
Haemophilus influenzae Description of the Pathogen H. influenzae is a small, nonmotile, non–spore-forming bacterium and a pathogen of humans found principally in the upper respiratory tract, first reported by Pfeiffer in 1892. The sensational claim that it was the primary agent of epidemic influenza proved fallacious; nonetheless, it has a wide range of pathogenic potential. Its requirement for growth factors, which can be supplied by erythrocytes,…
Revised August 2, 2021 Reviewed for currency January 14, 2021 The term dysentery was used by Hippocrates to indicate a condition characterized by the frequent passage of stool containing blood and mucus, accompanied by straining and painful defecation. It was not until the end of the 19th century, when the causes of amebiasis and bacillary dysentery were determined, that the two great forms of dysentery could…
Salmonellae are named for the pathologist Salmon, who was involved in the first isolation (by Theobald Smith) of Salmonella choleraesuis from the porcine intestine. Salmonella are effective commensals and pathogens that cause a spectrum of diseases in humans and animals, including domesticated and wild mammals, reptiles, birds, and insects. Some Salmonella serotypes, such as Salmonella enterica Typhi, Salmonella Paratyphi, and Salmonella Sendai, are highly adapted to…
Acinetobacter, an aerobic, catalase-positive, oxidase-negative, gram-negative coccobacillus, was first described in 1911, but the initial description of the taxonomy of this diverse species was not published until 1986. Ubiquitous in nature, the 54 species of the genus Acinetobacter are associated with a specific ecologic niche that shapes their genomic contents. ( Table 222.1 ) Acinetobacter baumannii is the most virulent species and causes the bulk of…
Revised August 10, 2021 The genus Burkholderia is currently composed of many species, but only three are notable pathogens for humans or animals: the former B. cepacia complex (described in Chapter 220 ), B. pseudomallei (the agent of melioidosis), and B. mallei (the agent of equine glanders). All three are aerobic, nonsporulating, straight or slightly curved gram-negative bacilli that were formerly placed in the genus Pseudomonas.…
Revised April 26, 2022 Stenotrophomonas maltophilia and the Burkholderia cepacia complex (BCC) cause infections in a variety of vulnerable patient populations including hospitalized patients such as patients with cancer and patients with specific genetic diseases such as cystic fibrosis (CF) and chronic granulomatous disease (CGD). The high level of inherent and acquired resistance to antibiotics makes treating these infections particularly challenging. Microbiology Both S. maltophilia and…
Revised November, 2019 Pseudomonas species are ubiquitous gram-negative bacteria capable of inhabiting a wide variety of diverse environments, including soil, water, plants, insects, and animals. Among all Pseudomonas species, P. aeruginosa is the most important species affecting humans and is responsible for serious debilitating and life-threatening infections. P. aeruginosa infections were noted in the literature in the 1800s when physicians began to report a “condition” causing…
Reviewed for currency November 8, 2020 The family Enterobacteriaceae belongs to the domain Bacteria, phylum Proteobacteria, class Gammaproteobacteria, and order Enterobacteriales ( ). The Enterobacteriaceae are gram-negative, non–spore-forming, facultative anaerobes that are typically motile by means of peritrichous flagella, ferment glucose, reduce nitrate to nitrite, and produce catalase but not oxidase. The family includes multiple genera implicated in human infection ( Table 218.1 ). TABLE…
Reviewed for currency January 14, 2021 Reviewed for currency January 14, 2021 Helicobacter pylori (formerly known as Campylobacter pylori or pyloridis ) was first isolated from humans in 1982. This highly motile, curved, gram-negative rod lives within the mucus layer overlying the gastric mucosal epithelium. H. pylori is commonly found in the human stomach, and when present, it is usually the single dominant species. Essentially all…
Revised July 1, 2020 Campylobacteriosis refers to the group of infections caused by gram-negative bacteria of the genus Campylobacter. Among the most common bacterial infections of humans in all areas of the world, Campylobacter spp. cause both diarrheal and systemic illnesses and may be associated with long-term sequelae. Infection of domesticated animals with Campylobacter is widespread. The name Campylobacter is derived from the Greek campylos, meaning…
Vibrio species are ubiquitous in estuarine waters in the temperate zones. Plankton blooms and temperature upshifting in the spring are followed by rapid outgrowth of most vibrios. Molluscan shellfish, which are filter feeders, acquire vibrios as part of their normal microbiota during the warmer months. Shellfish contamination by these vibrios thus occurs as a consequence of the normal climate-associated changes in Vibrio prevalence in coastal waters.…
Cholera is an acute and often severe watery diarrheal disease that is among the most rapidly fatal infectious diseases of humans. Previously well individuals infected with Vibrio cholerae, the comma-shaped gram-negative rod that causes this disease, can die from dehydration in less than a day. Two epidemiologic features of cholera also distinguish it from other diarrheal diseases. First, cholera can appear in explosive epidemics, particularly among…
Over the past 3 decades Moraxella (Branhamella) catarrhalis has emerged as an important and common human respiratory tract pathogen. In this chapter M. catarrhalis is discussed. In addition, Kingella and other gram-negative cocci, including Neisseria other than N. meningitidis and N. gonorrhoeae , and other Moraxella , which are less common causes of human infection, are considered. Acinetobacter is discussed in Chapter 222 , and Oligella…
Reviewed for currency November 8, 2020 Gonorrhea is a common bacterial infection that is transmitted almost exclusively by sexual contact or perinatally and primarily affects the mucous membranes of the urethra and cervix and, less frequently, those of the rectum, oropharynx, and conjunctivae. Ascending genital infection in women leads to endometritis and salpingitis—collectively called pelvic inflammatory disease (PID)—the predominant complication and one of the most common…