Staphylococci (Staphylococcus; ICD-10 A49.0: Staphylococcal infection of unspecified location) are Gram-positive, catalase-positive cocci that occur microscopically as pairs, as short chains, or as irregular clusters. Classification of the genus Staphylococcus according to the coagulase reaction has been established:
- Coagulase-positive staphylococci
- Staphylococcus aureus (in full: Staphylococcus aureus subsp. aureus; S. aureus).
- Staphylococcus agnetis* (coagulase variable).
- Staphylococcus aureus subsp. anaerobius* .
- Staphylococcus delphini*
- Staphylococcus hyicus* (coagulase variable)
- Staphylococcus intermedius* (rarely – insb. after dog bites – also in human wound infections).
- Staphylococcus lutrae*
- Staphylococcus pseudintermedius*
- Staphylococcus schleiferi subsp. coagulans*
- Coagulase-negative staphylococci* * .
- Staphylococcus epidermidis
- Staphylococcus haemolyticus
- Staphylococcus lugdunensis
- Staphylococcus saprophyticus subsp. saprophyticus
* Detection so far exclusively in animals or only very rarely in connection with infections in humans* * Hostile of the skin and mucous membranes without disease significance; in immunocompromised patients, however, of importance. Staphylococci are the most common pathogens of bacteremia (occurrence of bacteria in the blood in very large numbers). Staphylococcus aureus strains can produce Toxic Shock Syndrome Toxin-1 (TSST-1; about 5-20% of all isolates) and staphylococcal enterotoxins as superantigens. Antibiotic resistance: resistance to β-lactamase-sensitive penicillins (benzylpenicillin as test substance) is common (70-80% of all isolates). Resistance to other antibiotics often occurs as multiple resistance, predominantly in methicillin-resistant Staphylococcus aureus (MRSA). They are causative agents of nosocomial infections (hospital-acquired infections).Three variants of multidrug-resistant Staphylococcus epidermidis (S. epidermidis) have now also become known. The pathogen reservoir for S. aureus is humans, but animals can also be affected. In humans, the nasopharynx is preferentially colonized.For MRSA, humans are the germ carriers (diseased or clinically healthy), rarely domestic animals (dogs, cats, horses, pigs).One in four patients carried multidrug-resistant pathogens (MRE) on their hands when admitted to a U.S. rehabilitation facility. Occurrence: MRSA are common throughout the world. For both S. aureus and MRSA strains, transmission of the pathogen (route of infection) occurs from the affected patient (endogenous infections), or exogenously from other humans or animals, or via the inanimate environment (e.g., shared bath towels). In the hospital, transmission occurs through the hands, for example of the nursing and non-medical staff. Note: In the case of nasal colonization, the pathogen can spread from the nasal vestibule, the actual reservoir for S. aureus, to other areas of the skin (including hands, axilla, perineal region) and mucous membranes (e.g. pharynx). Depending on the type of pathogen, entry is enteral, parenterally, i.e. in this case, it enters the body by numerous routes: via the skin (percutaneous infection), via the mucous membranes (permucous infection), via the respiratory tract (inhalation infection), via the urinary tract (urogenital infection) or genitally (via the genital organs into the blood; genital infection). Human-to-human transmission: YesThe incubation period (time from infection to onset of disease) is a few hours (about 2-6 hours) for intoxications with orally ingested staphylococcal toxins, and 4-10 days for infections. Note: In case of colonization of individuals, endogenous infection may develop even months after initial colonization. The incidence (frequency of new cases) of multidrug-resistant germs is about 5 cases per 100,000 inhabitants per year. The duration of infectiousness (contagiousness) exists especially during the duration of clinically manifest symptoms. Note: Pathogens can also be transmitted from clinically healthy persons with a staphylococcal colonization.The disease does not lead to immunity. Course and prognosis: The course and prognosis of staphylococcal disease depends, among other things, on the localization of the infection and the patient’s immune status.Many MRSA transmissions go unnoticed, which favors the further spread of the pathogen.If the pathogen MRSA is detected, sanitation should be started. If the two control swabs (the first is performed after 3-6 months and the second after 12 months) are negative, the patient is considered to have been sanitized. The estimated lethality (mortality related to the total number of people with the disease) in Europe is 25,000 deaths due to infections with antibiotic-resistant pathogens per year based on figures from the European Centre for Disease Prevention and Control (ECDC) and the European Medicines Agency (EMA). There is a reporting requirement for multidrug-resistant germs (public health department).
