The impact of COVID-19 continuous containment and mitigation strategy on the epidemic of vector-borne diseases in China
Xiangyu Guo, Chenjin Ma, Lan Wang, Na Zhao, Shelan Liu, Wangli Xu
Abstract
BACKGROUND: This study explored the effect of a continuous mitigation and containment strategy for coronavirus disease 2019 (COVID-19) on five vector-borne diseases (VBDs) in China from 2020 to 2021. METHODS: Data on VBDs from 2015 to 2021 were obtained from the National Health Commission of the People's Republic of China, and the actual trend in disease activity in 2020-2021 was compared with that in 2015-2019 using a two-ratio Z-test and two proportional tests. Similarly, the estimated trend in disease activity was compared with the actual trend in disease activity in 2020. RESULTS: There were 13,456 and 3684 average yearly cases of VBDs in 2015-2019 and 2020, respectively. This represents a decrease in the average yearly incidence of total VBDs of 72.95% in 2020, from 0.9753 per 100,000 population in 2015-2019 to 0.2638 per 100,000 population in 2020 (t = 75.17, P < 0.001). The observed morbidity rates of the overall VBDs were significantly lower than the predicted rates (47.04% reduction; t = 31.72, P < 0.001). The greatest decline was found in dengue, with a 77.13% reduction (observed rate vs predicted rate: 0.0574 vs. 0.2510 per 100,000; t = 41.42, P < 0.001). Similarly, the average yearly mortality rate of total VBDs decreased by 77.60%, from 0.0064 per 100,000 population in 2015-2019 to 0.0014 per 100,000 population in 2020 (t = 6.58, P < 0.001). A decreasing trend was also seen in the monthly incidence of total VBDs in 2021 compared to 2020 by 43.14% (t = 5.48, P < 0.001). CONCLUSIONS: The results of this study verify that the mobility and mortality rates of VBDs significantly decreased from 2015-2019 to 2020-2021, and that they are possibly associated to the continuous COVID-19 mitigation and contamination strategy implemented in China in 2020-2021.