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| What is the rickettsial infection? |
- Typhus group (including epidemic typhus and endemic typhus);
- Spot fever group (including spot fever, Marseille fever, Australian rash typhus, rickett body pox);
- locust fever group (including tsutsugamushi disease);
- Q heat group (including Q heat);
- Paroxysmal rickettsial disease group (including war sputum fever). Epidemic typhus, endemic typhus, mites fever and Q fever have been found.
Rickettsia is a microbe between bacteria and viruses and has the following characteristics:
- Need to grow in living cells, and grow in the cells with metabolic decline;
- Typical cell walls, with DNA and RNA, are short, pleomorphic, and can be seen by light microscopy after staining.
- In addition to Q heat, sputum fever and rickettsial vaccinia, in vitro, it has a common antigen with some Proteus (OX19, OX2, OXK strains), so it can be used for external Fission (Proteus agglutination) To assist in the diagnosis.
- Sensitive to broad-spectrum antibiotics, such as tetracycline, chloramphenicol, etc.
- Its toxin is endotoxin, its main pathogenic substance.
- Resistant to low temperature, dry, sensitive to heat and general disinfectants.
The common features of rickettsial disease are:
- Pathogens are mainly propagated in nature in rodents (murines) and storage hosts such as livestock (bovine, sheep, dogs). Blood-sucking arthropods such as sputum, scorpion, scorpion and scorpion are the main vectors.
- Specific pathological changes are extensive perivascular inflammation and thrombotic vasculitis.
- The main clinical features are fever, headache and rash (except Q heat), showing acute manifestations.
- Broad-spectrum antibiotics are effective. Long-lasting immunity can be obtained after the disease, and there is cross-immunity between the diseases.
Rickettsia has epidemic typhus, murine typhus, ascariasis and Q fever.
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