江西口岸首例输入性卵形疟原虫wallikeri亚种感染的PCR鉴定及序列分析

PCR identification and sequence analysis of the first imported case of Plasmodium ovale wallikeri infection in Jiangxi port

目的对江西口岸1例输入性疟疾病例的血样本进行检测、确认。方法利用普通PCR检测全血样本中疟原虫18S r RNA基因,将得到的测序结果在NCBI数据库进行比对,并结合吉姆萨染色镜检、胶体金快速检测和荧光定量PCR加以验证。结果血涂片镜检并未发现疟原虫,但胶体金快速检测结果为阳性。普通PCR扩增到18S r RNA基因特异性片段,卵形疟原虫特异性引物扩增到阳性条带,而恶性疟、间日疟和三日疟原虫特异性引物没有扩增到目的条带。用卵形疟不同亚型引物特异性扩增发现卵形疟原虫wallikeri亚种阳性,序列与卵形疟原虫wallikeri亚种(Gen Bank号:KF219564.1和KF696359.1)18S r RNA同源性达99%。荧光定量PCR检测亦确认为卵形疟阳性。结论该病例确认为江西口岸首例输入性卵形疟wallikeri亚种感染。

Objective To test and confirm the Plasmodium ovale（P. ovale） from blood sample collected at Jiangxi port. Methods The 18 S r RNA PCR detection was conducted to confirm the infection,with Giemsa staining microscopy,colloidal gold rapid diagnostic test（RDT） and Real-time PCR as auxiliary detections. The amplified product was sequenced and blast on NCBI website. Results Microscopy detection showed a negative result,but RDT was positive. The 18 S r RNA gene amplification was positive by PCR with P. ovale specific primers,but negative by other three Plasmodium spp. specific primers. Additionally,the P. ovale wallikeri specific primers amplification obtained positive product. Sequence analysis showed that the sequence homology was up to 99% with P. ovale wallikeri 18 S r RNA gene（Accession No. KF219564.1,KF696359.1）. The Real-time PCR also confirmed the P. ovale infection.Conclusion The first imported P. ovale case at Jiangxi was confirmed as P. ovale wallikeri infection.