云南省独龙牛贾第虫分子流行病学调查

Molecular Epidemiological Investigation of Giardia lamblia in Bos frontalis from Yunnan Province,China

为了解云南省怒江州独龙牛贾第虫的感染情况及基因型,本试验分4个季节从怒江州怒江流域(古泉村、亚左洛村、鸠门当村、茨开镇)和独龙江流域(独龙江乡)5个地点采集987份独龙牛粪便标本,基于贾第虫的BG基因序列设计引物,采用巢式PCR方法对粪便DNA样本进行扩增。结果显示:贾第虫阳性样本共有102份,总感染率为10.33%,其中古泉村、亚左洛村、鸠门当村、茨开镇和独龙江乡感染率分别为10.19%(21/206)、13.90%(26/187)、11.98%(23/192)、8.33%(19/228)和7.47%(13/174),亚左洛村与独龙江乡之间感染率差异显著(P<0.05);独龙江流域与怒江流域的贾第虫感染率分别为7.47%(13/174)和10.95%(89/813),差异不显著(P>0.05);春、夏、秋、冬4个季节贾第虫感染率分别为12.05%(30/249)、10.55%(25/237)、8.68%(23/265)、10.17%(24/236),差异不显著(P>0.05);共鉴定出集聚体A、B和E三种基因型,均为人兽共患基因型。结果表明,怒江州独龙牛存在贾第虫感染,且存在人兽共患的风险,影响公共卫生安全,需采取相应措施进行预防。

In order to ascertain the infection and genotype status of Giardia lamblia(G.lamblia)in Nujiang Prefecture,Yunnan Province,this study collected a total of 987 fecal samples from Bos frontalis in Nujiang River basin(Guquan Village,Yazuoluo Village,Jiumendang Village,Cikai town)and Dulong River basin(Dulong River town)of Nujiang Prefecture over four seasons,and designed primers targeting the BG gene sequence of G.lamblia for nested PCR amplification of fecal DNA samples.The results showed that a total of 102 samples were positive for G.lamblia,with an average infection rate of 10.33%,ranging from 10.19%(21/206)in Guquan Village,13.90%(26/187)in Yazuoluo Village,11.98%(23/192)in Jiumendang Village,8.33%(19/228)in Cikai town,to 7.47%(13/174)in Dulong River town.There was a statistically significant difference in G.lamblia infection rates between Yazuoluo Village(13.90%or 26/187)and Dulong River town(7.47%or 13/174)(P<0.05),but there was no statistically significant difference in G.lamblia infection rates between Dulong River basin(7.47%or 13/174)and Nujiang River basin(10.95%or 89/813)(P>0.05).The infection rates of G.lamblia in spring,summer,autumn and winter were 12.05%(30/249),10.55%(25/237),8.68%(23/265)and 10.17%(24/236),respectively,which had no statistically significant difference(P>0.05).This study identified three G.lamblia genotypes(assemblages A,B,E),all of which were zoonotic genotypes.Thus,G.lamblia infection and zoonosis risk exist in Bos frontalis in Nujiang Prefecture,which poses a potential risk to public health,and calls for corresponding measures to prevent and control G.lamblia.