First molecular detection of Aichi virus in sewage and shellfish samples in the Monastir region of Tunisia

Abstract

The aims of our investigations were (1) to look for Aichi virus in environmental samples and (2) to compare the Aichi virus strains in both clinical and environmental samples in order to evaluate the role of environmental contamination as a possible vehicle for viral transmission. Aichi virus was detected in 15 (6%) sewage samples and in 4 (6.6%) shellfish samples. Aichi virus was identified for the first time in water samples. Phylogenetic analysis revealed several clusters that occurred sequentially in time, suggesting some parallelism in the evolution of environmental and human strains. Aichi virus present in sewage reflects the viruses circulating in the community.

Prevalence and Genetic Diversity of Aichi Viruses in Wastewater and River Water in Japan

“…A total of 260 distinct AiV strains were identified from wastewater and river water samples, with a considerable genetic diversity ( Fig. 1 and 2), which was much larger than the number of AiV strains identified in any other previous environmental studies (1,22). Among the strains identified, 255 were classified into genotype A and 5 were genotype B.…”

“…Fecal-oral AiV transmission through contaminated food or water is indicated by AiV detection in fecal samples of infected individuals (2, 7, 12-17, 19, 20, 23, 27) and raw and treated sewage (22), sewage-polluted river water (1), and shellfish samples (4,12,22). To further elucidate their prevalence and infection route, comprehensive documentation of their environmental occurrence and fate is essential.…”

“…Alcalá et al (1) examined only 11 sewage-polluted river water samples for AiVs, far fewer than were studied here. Furthermore, these studies performed direct nucleotide sequencing without molecular cloning, and both studies identified only a single genotype: genotype A by Sdiri-Loulizi et al (22) and genotype B by Alcalá et al (1). In contrast, we cloned the second-round PCR products and sequenced eight clones per sample.…”

Aichivirus in Children with Diarrhea in Northern Italy

“…Since its discovery, AiV has been detected with an incidence of 0.9–4.1%, primarily when studying outbreaks of diarrhea in children or young adults [14-18]. AiV seems to be circulating worldwide, and detection of AiV has been reported in Asia [19], South America [20], Europe [13-15, 20], and Africa [17]. Previous studies have suggested oysters, or other seafood, to be the source of AiV infections [2, 14, 17, 21, 22] but its occurrence has also been reported in sewage [17, 23], which indicates that kobuviruses might use the fecal-oral route of infection, like several other picornaviruses.…”

“…AiV seems to be circulating worldwide, and detection of AiV has been reported in Asia [19], South America [20], Europe [13-15, 20], and Africa [17]. Previous studies have suggested oysters, or other seafood, to be the source of AiV infections [2, 14, 17, 21, 22] but its occurrence has also been reported in sewage [17, 23], which indicates that kobuviruses might use the fecal-oral route of infection, like several other picornaviruses. Although doubts exist regarding its clinical role because of frequent codetection (50–80%) of AiV and other viral agents [14, 15, 24] and low incidence rates (0.9–4.1%) in acute gastroenteritis [15, 24-26], other studies have recently yielded contrasting results, showing that codetection of AiV with other common enteropathogenic viruses occurs at a low rate [27] and that this virus is rarely detected in healthy individuals [27-29], which supports a possible role of this virus in gastroenteritis.…”