Impact of COVID-19 Interventions on Respiratory and Intestinal Infectious Disease Notifications - Jiangsu Province, China, 2020-2023

Introduction: Many measures implemented to control the coronavirus disease 2019 (COVID-19) pandemic have reshaped the epidemic patterns of other infectious diseases. This study estimated the impact of the COVID-19 pandemic on respiratory and intestinal infectious diseases and potential changes following reopening.

Methods: The optimal intervention and counterfactual models were selected from the seasonal autoregressive integrated moving average (SARIMA), neural network autoregression (NNAR), and hybrid models based on the minimum mean absolute percentage error (MAPE) in the test set. The relative change rate between the actual notification rate and that predicted by the optimal model was calculated for the entire COVID-19 epidemic prevention period and the "reopening" period.

Results: Compared with the predicted notification rate based on the counterfactual model, the total relative change rates for the 9 infectious diseases were -44.24%, respiratory infections (-55.41%), and intestinal infections (-26.59%) during 2020-2022. Compared with the predicted notification rate based on the intervention model, the total relative change rates were +247.98%, respiratory infections (+389.59%), and intestinal infections (+50.46%) in 2023. Among them, the relative increases in influenza (+499.98%) and hand-foot-mouth disease (HFMD) (+70.97%) were significant.

Conclusions: Measures taken in Jiangsu Province in response to COVID-19 effectively constrained the spread of respiratory and intestinal infectious diseases. Influenza and HFMD rebounded significantly after the lifting of COVID-19 intervention restrictions.