Abstract:

Objective　To study the epidemiology of hand-foot-and-mouth disease (HFMD) and the spectrum of genotypes in the other enteroviruses (EVs) [non- enterovirus 71 (EV71) and non- Coxsaekievirus group A 16 (CA16)] in Guangzhou and Foshan area during and after the COVID-19 pandemic from 2022 to 2023. Methods　EV universal type, EV71, and CA16 were detected by real time fluorescent reverse transcription polymerase chain reaction (RT-PCR) respectively for suspected HFMD samples from 2022 to 2023. The positive specimens of non-EV71 and non-CA16 were amplified and sequenced based on 5′ UTR primers. The spectrum of genotypes was analyzed with BLAST in NCBI on the basis of 5'-UTR primers. Results　A total of 362 suspected HFMD specimens were collected in 2022, 47 (12.98%) of which were positive by real time simultaneous three virus detections. Among which, the positive rates of EV71, CA16, and non-EV71 and non-CA16 were 0, 1.38% (5/362), and 11.60% (42/362), respectively. A total of 297 suspected HFMD specimens were collected in 2023, 100 (33.67%) of which were positive by simultaneous three virus detections. Among which, the positive rates of EV71, CA16, and non-EV71 and non-CA16 were 0, 2.36% (7/297), and 31.31% (93/297), respectively. Sequence analysis of 51 non-EV71 non-CA16 positive samples showed that there were 9 genotypes of non-EV71 non-CA16 EVs detected from 2022 to 2023, which were CA6, CA10, CA4, CA2, CA8, CB5 (Coxsaekievirus group B 5), CB2, CB3, and E30 (echovirus 30), among which, CA6 accounted for 27.45% (14/51), followed by CA10, accounting for 15.69% (8/51). Conclusions　The EV infection rate after the COVID-19 pandemic in 2023 was higher than that in 2022 during the COVID-19 pandemic. The non-EV71 and non-CA16 EVs were the main causative agent of HFMD during 2022-2023. The sequence analysis showed that CA6 and CA10 were the most prevalent pathogens of non-EV71 and non-CA16 EVs, so, more attention should be paid to CA6 and CA10 of other type EVs.

Key words:

Hand-foot-and-mouth disease, Enterovirus, Non-EV71 and non-CA16 enteroviruses, Genotypes, Epidemiology

摘要：

目的　对比了解2022—2023年新冠疫情期间及疫情后广州市和佛山市手足口病流行病学及非肠道病毒71型（enterovirus 71，EV71）非柯萨奇病毒A组16型（Coxsaekievirus group A 16，CA16）病毒的分子流行病学特征，为治疗和防控提供依据。方法　运用荧光逆转录聚合酶链反应（RT-PCR）对2022—2023年疑似手足口病患者标本同时进行肠道病毒（enterovirus，EV）通用型、EV71、CA16检测，并选取EV71和CA16是阴性而EV通用型是阳性的标本进行型别鉴定，设计5′非编码区（UTR）引物，RT-PCR扩增后进行序列测定，序列用BLAST程序进行序列的EV型别确定。结果　2022年，同时进行EV通用型、EV71、CA16 3种病毒检测的疑似手足口病例标本共362份，总阳性47份，阳性率为12.98%；其中EV71阳性0份；CA16阳性5份，占1.38%；非EV71非CA16的EV阳性标本42份，占11.60%。2023年，同时进行EV通用型、EV71、CA16 3种病毒检测的疑似手足口病标本有297份，总阳性100份，阳性率为33.67%，全年没有检出EV71，CA16全年检出率为2.36%（7/297），非EV71非CA16的EV阳性率为31.31%（93/297）。51份非EV71非CA16阳性标本的序列分析表明，2022—2023检出的非EV71非CA16的EV有9种型别，分别为：CA6、CA10、CA4、CA2、CA8、柯萨奇病毒B组5型（CB5）、CB2、CB3、埃可病毒30型（E30），其中CA6占主要，为27.45%（14/51），其次是CA10，占15.69%（8/51）。结论　新冠疫情结束后的2023年比疫情期间的2022年EV阳性率高。2022—2023年手足口病主要以非EV71非CA16为主，序列分析表明非EV71非CA16病毒中以CA6和CA10为主，应加强对CA6、CA10为主要非EV71非CA16病毒进行研究及监测。

关键词:

手足口病, 肠道病毒, 非EV71非CA16肠道病毒, 基因型, 流行病学