摘要目的：分析2008—2015年河南省哨点医院5岁以下（1~59月龄）腹泻儿童A组轮状病毒的感染情况及临床和基因型别变迁特征。方法以2008—2015年河南省郑州市和开封市两家儿童医院内5岁以下（1~59月龄）住院腹泻儿童为研究对象。并于研究对象发病3 d或入院24 h内采集其粪便样本(每份3~5 ml)，共收集2541份，同时收集患者流行病学信息（月龄、性别等人口学信息及临床症状）。采用双抗体夹心ELISA法检测A组轮状病毒，阳性样本抽提病毒RNA，采用巢式多重RT-PCR进行G/P基因分型。采用χ2检验比较不同特征患者感染情况。结果2541份样本共检出A组轮状病毒785份，阳性率为30.9%。2008—2015年每年的10月份阳性率均较高，平均阳性率为54.8%（345/629）；每年的7月份阳性率均较低，平均阳性率为5.0%（5/101）。男童A组轮状病毒感染率为30.6%（451/1476），低于女童[31.4%（334/1065）]（χ2=0.18，P=0.664）；感染者主要为4~12月龄患者（61.3%，481/785），各月龄儿童感染率差异有统计学意义（χ2=196.69，P<0.001）；城市儿童阳性率为26.0%（258/992），低于农村[34.0%（527/1549）]（χ2=18.19，P<0.001）。785株A组轮状病毒G分型以G1、G2、G3、G9为主，分别占13.5%（106）、11.1%（87）、29.7%（233）、57.5%（451）；P分型以P[4]、P[8]为主，分别占11.3%（89）、84.7%（665）；型别组合以G9P[8]、G2P[4]、G3P[8]、G1P[8]为主，分别占52.9%（415）、9.7%（76）、17.3%（136）、11.3%（89）；G1[8]、G3P[8]逐年递减，G9P[8]逐年递增，已成为河南省A组轮状病毒优势型别。从临床体征看，594例（75.7%）阳性病例体温为<37℃，135例（17.2%）体温为37.0~37.5℃，16例（2.0%）体温为37.6~38.0℃，40例（5.1%）体温为>38℃；166例（21.1%）腹泻次数为0~3次，515例（65.6%）为4~6次，63例（8.0%）为7~9次，41例（5.2%）为10~15次；682例（86.9%）未发生呕吐，92例（11.8%）发生1~2次呕吐，47例（6.0%）发生3次呕吐，3例（0.4%）发生4次及以上呕吐；682例（86.9%）未发生脱水现象，95例（12.1%）发生1%~5%的轻度脱水现象，8例（1.0%）发生5%以上的中重度脱水现象。结论河南省哨点医院5岁以下（1~59月龄）腹泻儿童A组轮状病毒感染率较高；在秋季和春季时儿童感染率较高，且存在混合感染病例；病原体可分为多种基因型别，G9P[8]为主要优势型别；大部分感染病例无发热、呕吐、脱水症状，出现发热、腹泻、呕吐、脱水等临床症状的病例多以轻症为主。

abstractsObjective To investigate the infectious status, gene type transition and epidemiological features of rotavirus A isolated from infants and children (<59 months-of-age) in sentinel hospitals from 2008 to 2015 in Henan province, China. Methods In total, 2 541 stool samples (each 3-5 ml) were collected from infants and children aged less than five years in two sentinel hospitals and group A rotavirus was&nbsp;detected by a double antibody sandwich ELISA. Viral RNA was extracted from positive samples and G/P gene typing was performed using a two-step nested multiplex RT-PCR. Epidemiological information (including demographic information such as age, sex and clinical symptoms) was also collected from the patients and analyzed. Results Group A rotavirus was detected in 30.9%(785/2 541) of diarrhea samples from children. The detection rate was higher in October (54.8%, 345/629) and lower in July (5%, 5/101) each year from 2008 to 2015. The group A rotavirus infection rate was higher in boys (30.6%, 451/1 476) than in girls (31.4%, 334/1 065) (χ2=0.18, P=0.664). Infection mainly occurred in 4-12 months old patients (61.3%, 481/785) (χ2=196.69, P<0.001), and the infection rate was lower in cities (26%, 258/992) compared with rural areas (34.0%, 527/1 549) (χ2=18.19, P<0.001). G typing of 785 strains of group A rotavirus revealed the following types:G1 (13.5%, 106 strains), G2 (11.1%, 87 strains), G3 (29.7%, 233 strains), and G9 (57.5%, 451 strains);P typing revealed the predominance of P[4] (11.3%, 89 strains) and P[8] (84.7%, 665 strains); gene type combinations comprised mainly G9P[8], G2P[4], G3P[8], G1P[8], respectively accounted for 52.9%(415), 9.7%(76), 17.3%(136), 11.3%(89). Gene type combinations G1[8] and G3P[8] have been decreasing in prevalence since 2008 and G9P[8] has become the dominant gene type of group A rotavirus in Henan province. Among the group A rotavirus infection samples, the male:female infection ratio was 1.4∶1 (451/334), with no significant difference in the infection rate (χ2=0.18, P=0.664); the infection rate was higher in 4-12 months old patients (61.3%, 481/785), with a significant difference detected between age groups (χ2=196.69, P<0.001). The rate of detection was lower in cities (26.0%, 258/992) than in rural areas (34.0%, 527/1 549) (χ2=18.19, P<0.001). Clinical analysis revealed a body temperature of below 37 degrees in 75.7% of positive cases (594 patients), 37.0-37.5 degrees in 17.2% of cases (135 patients), 37.6-38.0 degrees in 2.0%of cases (16 patients), and above 38 degrees in 5.1%of cases (40 patients), with most cases showing no fever or a mild fever. The frequency of episodes of diarrhea among the patients was 0-3 times (21.1%, 166 cases), 4-6 times (65.6%, 515 cases), 7-9 times (8.0%, 63 cases), or 10-15 times (5.2%, 41 cases), mainly showing mild and moderate diarrhea. Vomiting also varied in frequency among the patients from no vomiting (86.9%, 682 cases), 1-2 times (11.8%, 92 cases), 3 times (6.0%, 47 cases), and more than 3 times (0.4%, 3 cases). The occurrence of dehydration varied from no dehydration (86.9%, 682 cases), mild dehydration of 1%-5% (12.1%, 95 cases), to severe dehydration of ≥5% (1.0%, 8 cases). Conclusion A higher infection rate of group A rotavirus was detected in children younger than five years of age with acute diarrhea in sentinel hospitals in Henan province, including part-mixed infection cases. A predominance of cases was detected in the autumn, and secondly the spring of each year. Gene type G9P[8] was most frequently isolated. The majority of patients displayed no fever, vomiting or dehydration. The cases with clinical symptoms of fever, diarrhea, vomiting and dehydration often showed mild disease.