Detection of norovirus and rotavirus in food samples by molecular and serological methods and determination of the effects of disinfectants on viruses

Although foodborne gastroenteritis outbreaks are generally thought to be bacterial in origin, it is reported that 67% of these outbreaks are caused by viruses. For this purpose, in this study, the risk of norovirus (NV) and rotavirus (RV) in various foods purchased from Adana/Turkey was evaluated. With the Systematic Review, potentially contaminated foods were associated and the presence of NV and RV in these related foods was investigated using both serological and molecular methods. Immunochromatographic rapid test cassettes were preferred as the serological method, and RT-PCR was preferred as the molecular method. In addition, the virus was purified by precipitation process and using proteinase K enzyme. To determine the performance of the methods in the study, recovery was performed with lettuce samples inoculated with 10 to the 9 NV and RV genome copies/ml. Additionally, different disinfectants were applied to various surfaces contaminated with NV and RV and antimicrobial activity against these viruses was evaluated. A total of 120 food samples from 7 food groups, including their repetitions, were used in the study. These 120 food samples include lettuce, cucumber, dill, mint, spinach, parsley, green onion, red pepper, radish, purslane, tomato, carrot, seasonal salad, onion salad, chopped tomato salad, cooked onion, ground meat, chicken breast, chicken thigh, raw fish, fresh strawberries, frozen strawberries, fresh blackberries, frozen blackberries, tap water, bici-bici, carrot juice, orange juice, frozen spinach, frozen corn, frozen peas, frozen red beans, raw milk, cheese, butter, yoghurt, bread, bagels, pastries and pita was present. As a result of the study, NV and RV were not detected in these food samples with both methods. However, the performance of the methods has been determined to be effective at high virus densities in foods. In detecting the high density of NV and RV inoculated into lettuce samples, viruses could be detected within the first 48 hours, but it was observed that the methods used after 48 hours were not effective. It has been observed that NV and RV with low virus density in various foods cannot be detected by RT-PCR and immunochromatographic rapid test cassettes, which are diagnostic methods. It is thought that this is due to the fact that foods have complex matrix structures, differing in terms of protein, fat and carbohydrate ratios, and viruses bind to these structures in various ways during the period. In recent years, with the increase in foodborne gastroenteritis outbreaks, the effectiveness of disinfectants used against viruses has begun to be questioned. In our study, when we look at the antimicrobial effects of disinfectants applied on NV and RV inoculated into lettuce, glass plates and plastic gloves; While disinfectants with an active ingredient rate of 10% sodium hypochlorite and 1% sodium hypochlorite have an antimicrobial effect, detergents containing 0.0015% hypochlorous, 1% methylisothiazolinone and disinfectants containing 65% ethyl alcohol have not been observed to have any effect on viruses. Although these disinfectants used in homes and businesses are used at the rates recommended by the companies, their lack of antimicrobial effect on NV and RV shows that these products should be developedfor viruses or not used for this purpose.