International Livestock Research Institute, Hanoi, Vietnam.
National Center for Veterinary Diagnosis, 15/78 Duong Giai Phong-Phuong Mai Dong Da Hanoi, Hanoi, Vietnam.
PLoS One. 2019 Aug 1;14(8):e0214701. doi: 10.1371/journal.pone.0214701. eCollection 2019.
Leptospirosis is an important zoonotic disease with a global distribution, affecting a wide range of mammalian animals and humans. Japanese encephalitis (JE) virus is the major vector-borne zoonotic disease in the Asia-Pacific region. The main objective of this study was to evaluate the seroprevalence of serovar-specific Leptospira and JE in swine from 10 provinces in Vietnam.
Samples were initially collected for swine influenza surveillance from March to April 2017 at large-scale farms (with at least 50 sows and/or 250 fattening pigs) with pigs that tested positive for influenza in the previous surveillance period (2015-16).
A total of 2,000 sera samples were analyzed from 10 provinces. Overall, the seroprevalence of leptospirosis was 21.05% (95% CI: 19.28-22.90) using a cut-off titer of ≥ 1:100. The apparent prevalence of JE was 73.45% (95% CI: 71.46-75.37) while the true prevalence was slightly higher (74.46%, 95% credible interval: 73.73-86.41). We found a relatively high presence of leptospirosis and JE in pigs kept on large farms. Prevalence was comparable with other studies suggesting opportunistic testing of samples collected for other surveillance purposes can be a valuable tool to better understand and prevent the potential transmission of these zoonotic diseases from pigs to people in Vietnam.
Our study provides evidence to veterinarians and animal health professionals for evidence-based practice such as diagnosis, vaccination and zoonotic control. Further investigation into the possible role of different domestic animals, wildlife species or environmental factors is needed to identify the potential risk factors and transmission routes in Vietnam.
钩端螺旋体病是一种具有全球分布的重要人畜共患病，影响范围广泛的哺乳动物和人类。日本脑炎（JE）病毒是亚太地区主要的虫媒传播的人畜共患病。本研究的主要目的是评估越南 10 个省份猪群中血清型特异性钩端螺旋体和 JE 的血清流行率。
样本最初是在 2017 年 3 月至 4 月间，在流感前哨监测期间检测到阳性的大型农场（至少有 50 头母猪和/或 250 头育肥猪）中，为猪流感监测而收集。
对来自 10 个省份的 2000 份血清样本进行了分析。总体而言，使用 ≥ 1:100 的截断滴度，钩端螺旋体病的血清流行率为 21.05%（95%置信区间：19.28-22.90）。JE 的显性流行率为 73.45%（95%置信区间：71.46-75.37），而真实流行率略高（74.46%，95%可信区间：73.73-86.41）。我们发现，大型农场中猪的钩端螺旋体病和 JE 感染率相对较高。这一流行率与其他研究相似，表明对其他监测目的采集的样本进行机会性检测可能是一种有价值的工具，可以更好地了解和预防这些人畜共患病从猪向越南人的潜在传播。
我们的研究为兽医和动物卫生专业人员提供了循证实践的证据，如诊断、疫苗接种和人畜共患病控制。需要进一步调查不同的家畜、野生动物物种或环境因素可能发挥的作用，以确定越南的潜在风险因素和传播途径。
