Frequency of Non-Polio Enteroviruses Among Acute Flaccid Paralysis Patients in Iran Before and During the COVID-19 Pandemic

During the COVID-19 pandemic public health measures and protocols such as regular hand washing and wearing a face mask were recommended at the national level. The implementation of these health protocols reduced the prevalence of respiratory diseases, but no study has been conducted to investigate the impact of the implementation of these protocols on the spread of viruses that are transmitted through fecal-oral route. Considering that non-polio enteroviruses (NPEVs) are mainly transmitted through fecal-oral route, this study was conducted to determine the prevalence of non-polio enteroviruses in patients with acute flaccid paralysis (AFP) in Iran before and during the COVID-19 pandemic.

To detect non-polio enteroviruses stool samples of AFP cases received by Iran National Polio Laboratory in 2019 (before the COVID-19 pandemic) and 2021 (during the COVID-19 pandemic) were tested. To isolate NPEVs by cell culture, the WHO standard protocol was used, and the TaqMan One-Step Real Time PCR was used for molecular testing.

In 2019, a sample of 21 out of 1070 patients and a sample of 12 out of 100 patients were found to be positive for non-polio enterovirus by cell culture and the molecular method, respectively; these ratios decreased to10 out of 678 and 3 out of 100 in 2021.

Based on the findings of this study, it can be concluded that the observance of personal hygiene and public health protocols during the COVID-19 epidemic  have, in addition to the general reduction of respiratory transmission of viruses, also affected the faecal-oral transmission of viruses.