Background:Babesiosis is an uncommon but emerging tick-borne disease caused by the genus Babesia.In this case study,we report a case of human infection with a novel Babesia sp.in China.Findings:The patient in question...Background:Babesiosis is an uncommon but emerging tick-borne disease caused by the genus Babesia.In this case study,we report a case of human infection with a novel Babesia sp.in China.Findings:The patient in question had been suffering from repetitive occurrences of mild fever of unknown origin and fatigue for 10 years.Ring forms,tetrads,and one or two dots of chromatin or trophozoite-like organisms were observed in the patient’s thin blood smears and bone marrow smears.Using a confocal laser-scanning microscope,it was observed that the patient’s serum had reactivity with the surface proteins of the B.microti strain.Electron microscopy revealed oval red blood cells with 1~2μm of knob protrusions in the cellular membrane.The results of the Babesia-specific nested PCR assay for 18S rRNA confirmed the presence of Babesia infection.The construction of a phylogenetic relationship showed clustering with B.microti and B.duncani,which was identified as a novel Babesia species and named as Babesia sp.XXB/HangZhou.Azithromycin,doxycycline,and moxifloxacin hydrochloride were shown to relieve symptoms but were not as effective after continuous usage.After atovaquone(Mepron®)administration,the patient recovered from fever and tested negative for detection of Babesia-specific genes.Conclusion:Babesia sp.XXB/HangZhou is a novel Babesia species,which causes mild babesiosis in an immunocompetent patient.展开更多
基金supported by the Special Fund for Health Research in the Public Interest,China(Grant No.201202019)the National Key Science&Technology Special Projects on Major Infectious Diseases,China(Grant No.2012ZX10004-211).
文摘Background:Babesiosis is an uncommon but emerging tick-borne disease caused by the genus Babesia.In this case study,we report a case of human infection with a novel Babesia sp.in China.Findings:The patient in question had been suffering from repetitive occurrences of mild fever of unknown origin and fatigue for 10 years.Ring forms,tetrads,and one or two dots of chromatin or trophozoite-like organisms were observed in the patient’s thin blood smears and bone marrow smears.Using a confocal laser-scanning microscope,it was observed that the patient’s serum had reactivity with the surface proteins of the B.microti strain.Electron microscopy revealed oval red blood cells with 1~2μm of knob protrusions in the cellular membrane.The results of the Babesia-specific nested PCR assay for 18S rRNA confirmed the presence of Babesia infection.The construction of a phylogenetic relationship showed clustering with B.microti and B.duncani,which was identified as a novel Babesia species and named as Babesia sp.XXB/HangZhou.Azithromycin,doxycycline,and moxifloxacin hydrochloride were shown to relieve symptoms but were not as effective after continuous usage.After atovaquone(Mepron®)administration,the patient recovered from fever and tested negative for detection of Babesia-specific genes.Conclusion:Babesia sp.XXB/HangZhou is a novel Babesia species,which causes mild babesiosis in an immunocompetent patient.
