Fresh vegetables and shellfish are prone to microbial contamination through irrigation or breeding with sewage-polluted waters, as well as by infected food handlers. In this work, we studied the presence of human and bovine polyomaviruses and human norovirus in fresh lettuces, strawberries and oysters produced in Buenos Aires province, Argentina. In oysters, we also investigated F-specific RNA bacteriophages, indicator Escherichia coli (E. coli) and pathogen bacteria of concern (Salmonella spp., Vibrio spp.). Within vegetables, we found viral contamination of human origin given the presence of human-associated polyomaviruses -MCPyV, HPyV6, JCPyV, and SV40- in lettuce and strawberry samples (16 and 10%, respectively), probably coming from irrigation waters and food handling. Among oysters, human (MCPyV, 4.2%) and bovine (BPyV1, 8.4%) polyomaviruses were detected even with low counts of E. coli. Bacteriophages (n = 3) and Salmonella spp. (n = 1) were also found, while Vibrio spp. was not detected. These results may indicate that the contamination in oysters comes from human and animal excreta, probably present in breeding waters. Norovirus was not detected in any food sample. To our knowledge, this is the first description of SV40 in lettuces and MCPyV and BPyV1 in oysters. The detection of different viral contaminants encourages further studies to evaluate the need for including viral indicators in microbiological standards. The identification of possible sources and routes of contamination using viral markers during routine microbiological controls, such as the polyomaviruses used in this work, would be useful to focus attention on the most hazardous stages of the food production chain.

新鲜蔬菜和贝类很容易通过灌溉或用污水污染的水繁殖，以及被感染的食品处理者而受到微生物污染。在这项工作中，我们研究了阿根廷布宜诺斯艾利斯省生产的新鲜生菜、草莓和牡蛎中存在人和牛多瘤病毒和人诺如病毒。在牡蛎中，我们还研究了 F 特异性 RNA 噬菌体、指示剂大肠杆菌（大肠杆菌）和关注的病原体细菌（沙门氏菌属、弧菌种）。在蔬菜中，鉴于生菜和草莓样本（分别为 16% 和 10%）中存在与人类相关的多瘤病毒 -MCPyV、HPyV6、JCPyV 和 SV40，我们发现了人类来源的病毒污染，可能来自灌溉水和食品处理. 在牡蛎中，即使大肠杆菌的数量很少，也检测到人（MCPyV，4.2%）和牛（BPyV1，8.4%）多瘤病毒。噬菌体 ( n  = 3) 和沙门氏菌属。( n  = 1) 也被发现，而弧菌spp. 没有被检测到。这些结果可能表明牡蛎中的污染来自人类和动物的排泄物，可能存在于繁殖水域中。在任何食物样本中均未检出诺如病毒。据我们所知，这是对生菜中 SV40 和牡蛎中 MCPyV 和 BPyV1 的首次描述。不同病毒污染物的检测鼓励进一步研究以评估将病毒指标纳入微生物标准的必要性。在常规微生物控制过程中使用病毒标记物（例如本工作中使用的多瘤病毒）识别可能的污染源和污染途径，将有助于将注意力集中在食品生产链中最危险的阶段。