Optimization of RT-qPCR for Detection of Aichi Virus in Sewage and River Water Samples in Karaj, Iran

Background: Aichi virus (AiV) is an emerging virus, which belongs to Kobuvirus genus of the Picornaviridae family. AiV was recently determined as an etiologic agent of gastroenteritis in susceptible humans. After shedding of virus particles from affected people, AiV particles can contaminate water sources. Then, infection with this virus occurs in humans by the fecal-oral route after exposure with contaminated waters. Thus far, some research around the world demonstrated that different kinds of water sources including river water, ground water and treated or untreated sewage water have contamination with AiVs. Molecular detection of AiV has been mostly depended on reverse transcription polymerase chain reaction (RT-PCR) methods, which targeted 3CD junction region of the virus genome. Methods: The present study aims to assess the molecular detection of AiVs in treated and untreated sewage water and river water specimens by the development of reverse transcription-quantitative PCR (RT-qPCR) assay for all AiV genotypes. Results: Out of 50 samples tested (consisting of 28 river water samples and 22 sewage water samples), the AiV genomic RNA was identified in 15/28 (~50%) river water samples and in 14/22 (~70%) sewage samples. Conclusion: Our results, for the first time, indicate that AiVs have been circulating in Iran.