Introduction

We define a fluid library as a library of samples of different biological fluids (from humans, animals or vectors) collected and properly stored on filter paper, which allows retrospective studies, especially of diagnosis or detection of infectious agents in these samples, using different techniques. The objective of this work was the retrospective diagnosis of American trypanosomiasis by PCR in a Venezuelan endemic area using a fluid library.

Methods

A fluid library with samples that had been collected on filter paper, 5 years ago, was used for the detection of Trypanosoma cruzi DNA. 165 blood samples of humans, 30 samples of 25 animals (Didelphis marsupialis, Canis familiaris, Equus asinus and Felis catus) and 8 samples of vectors from endemic areas of Anzoátegui state, were analysed by PCR.

Results

The results revealed that 16.4% of the humans samples were positive, 11.1% of those detected positive were children younger than 10 years old, and 26.72% young people aged 11–20 years, suggesting that T. cruzi infection has been active for the past two decades. 56% of the animal samples showed amplification; Didelphis marsupialis 66%, Canis familiaris 54.5%, Equus asinus 50%, and Felis catus 33.3%. On the other hand, positivity (50%) was detected in the studied vectors, of which the 3 most important species in Venezuela (Rhodnius prolixus, Triatoma maculata and Panstrongylus geniculatus) were involved.

Conclusions

The PCR using a fluid library allowed the detection of T. cruzi DNA in old samples from the three host of the epidemiological chain, suggesting that retrospective diagnosis can be made through this strategy and demonstrate that there has been active transmission, which helps to clarify the epidemiological situation in areas where there are no previous reports.

中文翻译：

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具有在滤纸中收集的人类、水库和载体样本的流体库的效用，用于委内瑞拉流行地区美国锥虫病的回顾性诊断。

简介

我们将体液库定义为收集并正确存储在滤纸上的不同生物体液（来自人类、动物或载体）的样本库，它允许使用不同技术进行回顾性研究，尤其是对这些样本中传染性病原体的诊断或检测. 这项工作的目的是使用流体库在委内瑞拉流行地区通过 PCR 对美国锥虫病进行回顾性诊断。

方法

5 年前在滤纸上收集的样本的流体库用于检测克氏锥虫DNA。通过 PCR 分析了人类的 165 份血液样本、25 只动物（有袋袋鼠、家犬、马属和猫科动物）的 30 份样本和来自安索阿特吉州流行地区的 8 份载体样本。

结果

结果显示，16.4%的人类样本呈阳性，11.1%的检测呈阳性的是10岁以下的儿童，26.72%的11-20岁的年轻人，表明T. cruzi感染过去一直很活跃两个十年。56% 的动物样本显示出扩增；Didelphis marsupialis 66%、Canis associateis 54.5%、Equus asinus 50% 和Felis catus 33.3%。另一方面，在研究的载体中检测到阳性（50%），其中涉及委内瑞拉的 3 个最重要的物种（Rhodnius prolixus、Triatoma maculata和Panstrongylus geniculatus）。

结论

使用流体文库的 PCR 允许在来自流行病学链的三个宿主的旧样本中检测到T. cruzi DNA，表明可以通过该策略进行回顾性诊断并证明存在主动传播，这有助于澄清以前没有报告的地区的流行病情况。