PDF(Pubmed)
Abstract：
BACKGROUND: Equid alphaherpesvirus 1 (EHV-1) is a highly contagious respiratory tract pathogen of horses, and infection may be followed by myeloencephalopathy or abortion. Surveillance and early detection have focused on PCR assays using less tolerated nasal swabs. Here, we assess non-invasive non-contact sampling techniques as surveillance tools in naturally equid gammaherpesvirus 2-shedding horses as surrogates for EHV-1.
METHODS: Horses were individually housed for 10 h periods on 2 consecutive days. Sampling included nasal swabs, nostril wipes, environmental swabs, droplet-catching devices, and air sampling. The latter was completed via two strategies: a combined air sample collected while going from horse to horse and a collective air sample collected at a stationary central point for 6 h. Samples were screened through quantitative PCR and digital PCR.
RESULTS: Nine horses on day 1 and 11 horses on day 2 were positive for EHV-1; overall, 90.9% of the nostril wipes, 81.8% of the environmental surfaces, and 90.9% of the droplet-catching devices were found to be positive. Quantitative analysis showed that the mean DNA copies detection per cm2 of nostril wipe sampled concentration (4.3 × 105 per day) was significantly (p < 0.05) comparable to that of nasal swabs (3.6 × 105 per day) followed by environmental swabs (4.3 × 105 per day) and droplet catchers (3.5 × 103 per day), respectively. Overall, 100% of the air samples collected were positive on both qPCR and dPCR. In individual air samples, a mean concentration of 1.0 × 104 copies of DNA were detected in per m3 air sampled per day, while in the collective air samples, the mean concentration was 1.1 × 103.
CONCLUSIONS: Environmental samples look promising in replacing direct contact sampling. Environmental and air sampling could become efficient surveillance tools at equestrian events; however, it needs threshold calculations for minimum detection levels.
METHODS: Horses were individually housed for 10 h periods on 2 consecutive days. Sampling included nasal swabs, nostril wipes, environmental swabs, droplet-catching devices, and air sampling. The latter was completed via two strategies: a combined air sample collected while going from horse to horse and a collective air sample collected at a stationary central point for 6 h. Samples were screened through quantitative PCR and digital PCR.
RESULTS: Nine horses on day 1 and 11 horses on day 2 were positive for EHV-1; overall, 90.9% of the nostril wipes, 81.8% of the environmental surfaces, and 90.9% of the droplet-catching devices were found to be positive. Quantitative analysis showed that the mean DNA copies detection per cm2 of nostril wipe sampled concentration (4.3 × 105 per day) was significantly (p < 0.05) comparable to that of nasal swabs (3.6 × 105 per day) followed by environmental swabs (4.3 × 105 per day) and droplet catchers (3.5 × 103 per day), respectively. Overall, 100% of the air samples collected were positive on both qPCR and dPCR. In individual air samples, a mean concentration of 1.0 × 104 copies of DNA were detected in per m3 air sampled per day, while in the collective air samples, the mean concentration was 1.1 × 103.
CONCLUSIONS: Environmental samples look promising in replacing direct contact sampling. Environmental and air sampling could become efficient surveillance tools at equestrian events; however, it needs threshold calculations for minimum detection levels.
摘要：
背景：等效α疱疹病毒1（EHV-1）是马的高度传染性呼吸道病原体，感染后可能会出现骨髓性脑病或流产。监测和早期检测集中在使用耐受性较低的鼻拭子的PCR测定上。这里,我们评估了非侵入性非接触采样技术作为EHV-1替代的自然配对γ疱疹病毒2型脱落马的监测工具。
方法：连续2天将马单独饲养10小时。取样包括鼻拭子，鼻孔湿巾,环境拭子,液滴捕获装置,空气采样。后者是通过两种策略完成的：从马到马时收集的组合空气样品和在固定中心点收集的集体空气样品6小时。通过定量PCR和数字PCR筛选样品。
结果：第1天的9匹马和第2天的11匹马对EHV-1呈阳性；总体而言，90.9%的鼻孔湿巾，81.8%的环境表面，发现90.9%的液滴捕获装置为阳性。定量分析表明，每cm2鼻孔擦拭采样浓度（每天4.3×105）的平均DNA拷贝检测与鼻拭子（每天3.6×105）和环境拭子（每天4.3×105）和液滴捕获器（每天3.5×103）相当，分别。总的来说,所收集的空气样品的100%在qPCR和dPCR中均为阳性。在单个空气样本中，每天每m3空气采样中检测到1.0×104个DNA拷贝的平均浓度，在集体空气样本中，平均浓度为1.1×103。
结论：环境样品在取代直接接触取样方面看起来很有希望。环境和空气采样可以成为马术活动的有效监测工具；然而，它需要最小检测水平的阈值计算。
方法：连续2天将马单独饲养10小时。取样包括鼻拭子，鼻孔湿巾,环境拭子,液滴捕获装置,空气采样。后者是通过两种策略完成的：从马到马时收集的组合空气样品和在固定中心点收集的集体空气样品6小时。通过定量PCR和数字PCR筛选样品。
结果：第1天的9匹马和第2天的11匹马对EHV-1呈阳性；总体而言，90.9%的鼻孔湿巾，81.8%的环境表面，发现90.9%的液滴捕获装置为阳性。定量分析表明，每cm2鼻孔擦拭采样浓度（每天4.3×105）的平均DNA拷贝检测与鼻拭子（每天3.6×105）和环境拭子（每天4.3×105）和液滴捕获器（每天3.5×103）相当，分别。总的来说,所收集的空气样品的100%在qPCR和dPCR中均为阳性。在单个空气样本中，每天每m3空气采样中检测到1.0×104个DNA拷贝的平均浓度，在集体空气样本中，平均浓度为1.1×103。
结论：环境样品在取代直接接触取样方面看起来很有希望。环境和空气采样可以成为马术活动的有效监测工具；然而，它需要最小检测水平的阈值计算。
