Habitat or reservoir

Pseudomonas aeruginosa

found in the environment (soil, water and plants) and it survives well in domestic environments such as in hot tubs, whirlpools, contact lens solutions. In the hospital environment, it will dwell in the sink, shower, and respiratory equipment.

Pseudomonas putida and Pseudomonas fluoroscens

• Rarely causes clinical disease due to these organisms being of low virulence.

• There are reported cases of UTI, post-surgical abscesses, empyema, septic arthritis, and other wound infections.

Pseudomonas putida

associated with catheter-related sepsis in patients with cancer.

Pseudomonas orzyhabitans

• Has been found in Japanese rice paddies and has been isolated form hospital drains and respiratory therapy equipment.

• This organism has been isolated from the eye of one patient with post-operative endophthalmitis.

Pseudomonas luteola

Has been recovered as the only isolate from a case of prosthetic valve endocarditis and subdiaphragmatic abscess and multiple brain abscess in a child.

Acinetobacter species

• Inhabit the environment and can be found in fomites and animal food products.

• usually occur in areas with high fluid contents such as urinary tract and respiratory tract and in peritoneal fluids.

Stenotrophomonas maltophilia

• The third most common non-fermentative gram negative bacillus isolated in the laoratory

• It is found in the environment and it is not a part of normal flora in humans, but it can quickly colonize the respiratory tract of hospitalized patients

Burkholderia species

Generally non-pathogenic and are found in soil, plants, and water.

Burkholderia mallei

• Causes Glanders (Zoonotic respiratory disease affecting horses, mules, and donkeys)

• Rare in humans but can produce severe local suppurative or acute pulmonary infections

Burkholderia pseudomallei

Found in water and muddy soils, common in Southeast Asia and Northern Australia.

Burkholderia gladioli

Plant pathogen

Aeromonas

• Reservoirs: widely distributed in freshwater, estuarine, and marine environments; found in fish, reptiles, and mammals.

• Frequently isolated from retail produce sources and animal meat products

• Fish, reptiles, amphibians, mammals and humans

Moraxella catarrhalis

• Is the most frequent isolate in the genus Moraxella from clinical specimens, especially from respiratory and ear specimens.

• Is a commensal of the upper respiratory tract and it is an opportunistic pathogen.

• It is the third most common cause of acute otitis media and sinusitis in children.

• It can also cause lower respiratory infections especially in adults with chronic obstructive pulmonary disease.

Moraxella nonliquefaciens

• It is the second most frequently isolated member of the genus Moraxella.

• It is a normal flora of the respiratory tract of humans, and it rarely causes disease in humans.

Moraxella lacunata

• Frequently isolated from the conjunctiva

• eye infections and it is able to liquefy serum

Moraxella oslensis

Normal flora in the genitourinary tract

Oligella

isolated from the urinary tract

Alcaligenes

Found in water

Alcaligenes faecalis

Linked to eye infections and pancreatic abscess

Achromobacter denitrificans

Has been recovered from urine, prostate secretions, the buccal cavity, pleural fluid, and eye secretions

Achromobacter xylosoxidans

Reservoirs for this organism are soil and water, and commonly found in tropical and subtropical climates, in particular Southeast Asia and India.

Elizabethkingia meningoseptica

• Causes meningitis or septicemia in newborns

• it also causes pneumonia, endocarditis, bacteremia, and meningitis in adults.

Ralstonia pickettii

Meningitis, endocarditis, and osteomyelitis.

Ralstonia mannitolilytica

Most often caused infection to patients with cystic fibrosis

Sphingomonas paucimobilis

Are known for their water-borne nature, so it's isolated from water sources.

Sphingomonas parapaucimobilis

Isolated from sputum, urine, and vaginal specimens

HACEK group

Are part of the normal oral flora and are opportunistic pathogen.

Aggregatibacter actinomycetemcomitans

• Human tissue infections have been attributed to bites by cattle, sheep, pigs, and horses or through contact with these animals.

• Normal flora in humans and is a major contributor to periodontitis.

Aggregatibacter aphrophilus

• Found in dental plaque and gingivalism

• One of the most prevalent species in the HACEK group involved in endocarditis.

Cardiobacterium hominis

Normal flora of the nose, mouth, throat, and may also be found in genitourinary and gastrointestinal tract

Eikenella corrodens

Member of the normal flora of the oral and bowel cavities

Kingella kingae

• Member of the normal oropharynx microbiota or flora.

• Recognized as important pathogens in the pediatric population and have a predilection for bones and joints.

• It's the most common cause of osteoarthritis infection in children younger than four years of age.