细环病毒（TTV）是近年来发现的一种新型人畜共患DNA病毒，广泛存在于包括人类和家畜在内的多种哺乳动物中。目前我国猪群中TTV的流行病学报道较少。为研究猪细环病毒（PTTV）在我国的流行情况，本文采用聚合酶链反应（PCR）对2009年我国9个省市部分发病猪场中的PTTV1和PTTV2进行分子检测。结果显示，191份病料中PTTV的总阳性率为77.0% （147/191），其中PTTV1的单一阳性率为68.6%（131/191），PTTV2的单一阳性率为53.9% （103/191），两基因型的共感染率为45.5%（87/191）。进一步分析发现，在不同猪场、不同年龄猪群、不同病料组织中，PTTV的感染情况均不相同。此外，对41份健康猪的血清进行检测，结果显示，PTTV阳性率、PTTV1阳性率、PTTV2阳性率及两基因型的共感染率分别为43.9%（18/41）、36.6% （15/41）、24.4% （10/41）和12.2%（5/41）。提示发病猪体内PTTV总阳性率、PTTV1单一阳性率、PTTV2单一阳性率及两基因型的共感染率均显著高于健康猪（P<0.01）。PTTV在临床上是否对猪致病或与其他病原有协同作用，需进一步研究。

Torque teno virus (TTV) is an emerging zoonotic DNA virus, which is frequently detected in many vertebrates including humans and livestock. At present, there was little report on PTTV prevalence in China. In order to know the epidemic status of PTTV in China, detection of PTTV1 and PTTV2 in 191 samples from diseased pigs collected from nine different regions were performed. The results showed that 147 samples (77.0%) were positive for PTTV. Among them, 131 samples (68.6%) were positive for PTTV1, 103 samples (53.9%) were positive for PTTV2, and 87 samples (45.5%) were positive for both PTTV1 and PTTV2. Further analysis revealed that infection rates of PTTV in different farms, sample types, pig ages were different. Forty-one serum samples collected from healthy pigs were also detected. The results showed that 18 samples (43.9%) were positive for PTTV. Among them, 15 samples (36.6%) were positive for PTTV1, 10 samples (24.4%) were positive for PTTV2, and 5 samples (12.2%) were positive for both PTTV1 and PTTV2. The results indicated that PTTV had significant higher prevalence in diseased pigs than that in healthy pigs (P<0.01). Whether PTTV plays a role in swine disease or has a synergistic effect with other pathogens should be further studied.