Effects of the enhanced public health intervention during the COVID-19 epidemic on respiratory and gastrointestinal infectious diseases in China

The public health interventions to mitigate coronavirus disease 2019 (COVID-19) could also potentially reduce the global activity of influenza. However, this strategy's impact on other common infectious diseases is unknown. We collected data of 10 respiratory infectious (RI) diseases, influenza-like illnesses (ILIs), and seven gastrointestinal infectious (GI) diseases during 2015-2020 in China and applied two proportional tests to check the differences in the yearly incidence and mortality, and case-fatality rates (CFRs) over the years 2015-2020. The results showed that the overall RI activity decreased by 7.47%, from 181.64 in 2015-2019 to 168.08 per 100 000 in 2020 (p < 0.001); however, the incidence of influenza was seen to have a 16.08% escalation (p < 0.001). In contrast, the average weekly ILI percentage and positive influenza virus rate decreased by 6.25% and 61.94%, respectively, in 2020 compared to the previous 5 years (all p < 0.001). The overall incidence of GI decreased by 45.28%, from 253.73 in 2015-2019 to 138.84 in 2020 per 100 000 (p < 0.001), and with the greatest decline seen in hand, foot, and mouth disease (HFMD) (64.66%; p < 0.001). The mortality and CFRs from RI increased by 128.49% and 146.95%, respectively, in 2020, compared to 2015-2019 (p < 0.001). However, the mortality rates and CFRs of seven GI decreased by 70.56% and 46.12%, respectively (p < 0.001). In conclusion, China's COVID-19 elimination/containment strategy is very effective in reducing the incidence rates of RI and GI, and ILI activity, as well as the mortality and CFRs of GI diseases.