Peripheral blood smear of a patient with relapse of a fever seven days after remittance is shown. True statement about the etiological agent-
Loosely wound spiral forms on peripheral blood smear shows Borrelia. Diagnosis is relapsing fever. Louse-borne/Epidemic Relapsing fever Tick-borne/endemic relapsing fever Cause-Borrelia recurrentis At least 15 spp- B.duttonii, B.parkeri, B.hermsii B. turicata Tends to occur as epidemic Sporadic cases in endemic areas Vector-body louse Vector-soft tick Inoculation of louse feces into skin Transmitted by bite of soft tick No extra-human reservoir Rodents and other mammals Disease -severe. Disease -milder. CFR-4-40% CFR-1-4% Relapses-1/2 Frequent relapses
The only reservoir is humans
Vector is hard tick or body louse
It is non-cultivable on cell free media.
Soft tick or body louse can transmit the disease
Systemic Bacteriology (Haemophilus, Yersinia, Spirochaetes, Ricketssia, Chlamydia, Mycoplasma and Miscellaneous Bacteria)