In vitro inhibition of rotavirus multiplication by copper oxide nanoparticles.

Group A rotaviruses are the most common cause of gastroenteritis in children under five years of age worldwide. Rotavirus gastroenteritis can be related to mild to severe diarrhea in children and in some cases, can lead to death due to severe dehydration. Approximately 146,480 people die annually from rotavirus infection worldwide, and most of these deaths occur in low-income countries in Africa and Asia. Since there are no specific effective drugs to treat rotavirus infections, and infected patients can only be treated supportively, new antiviral agents need to be developed. Copper oxide nanoparticles (CuO NPs) have a wide range of applications in the magnetic and electrical industries, as well as in biology. The antiviral activity of nanoparticles (CuO NPs) is well documented. This study aimed to investigate the antiviral effect of CuO NPs on rotaviruses. The cytotoxic effects of CuO NPs on MA-104 cells were examined by methyl thiazolyl tetrazolium assay. In addition, the anti-rotavirus activity of CuO NPs was evaluated by TCID₅₀ and real-time polymerase chain reaction PCR assay. Our results showed that exposure of rotavirus-infected cells to various non-toxic concentrations of CuO NPs did not cause a decrease in viral titer, compared to the control. However, the virucidal effect of CuO NPs on rotavirus was observed at concentrations of 80 and 100 μg/ml (P<0.001). Our study suggested that CuO NPs had significant antiviral activity against rotavirus replication. However, the exact mechanism of anti-rotavirus activity of CuO NPs remained unknown. According to the virucidal assay, it appears that the loss of capsid integrity and genome disruption in the presence of CuO NPs are possible mechanisms of its anti-rotavirus activity.