RESUMEN
Objective To predict the coronavirus disease 2019 (COVID-19) epidemic situation based on the infectious disease dynamics susceptible-exposed-infected-recovered (SEIR) model, so as to provide guidance for effective control of the epidemic. Methods Python crawler automatic update function was used to collect the epidemic data released by the National Health Commission of China. An improved infectious disease dynamics SEIR model, which can automatically correct the COVID-19 basic reproductive number (R0), was constructed to predict the development trend of COVID-19 epidemic in Hubei Province of China and South Korea. Results The peak of the COVID-19 epidemic in Hubei Province of China predicted by the model would appear on Feb. 21, 2020. The number of confirmed COVID-19 cases would be about 50 000 on Feb. 19 and would fall to below 30 000 on Mar. 4, and the epidemic would end on May 10. According to the actual data released by the National Health Commission of China, the peak number of confirmed COVID-19 patients was 53 371. The model predicted that an epidemic peak in South Korea would be on Mar. 7, and would end at the end of April. Conclusion This improved infectious disease dynamics SEIR model established in the early stage of COVID-19 epidemic has achieved relatively accurate prediction. The timely and effective intervention by relevant government departments has significantly affected the development of the epidemic. The epidemic situation in other countries in East Asia, such as South Korea, is still on the rise in March, suggesting that China needs to be on guard against the risk of imported epidemic.
RESUMEN
Objective To understand the dynamic status of schistosomiasis epidemic situation and Oncomelania hupensis snail status before and after the schistosomiasis transmission interrupted in the mountainous areas of Yunnan Province. Methods The data of schistosomiasis epidemic situation and snail status were collected and analyzed statistically in Jianchuan County from 10 years before the schistosomiasis transmission interrupted to 2008. Results The schistosomiasis control began in Jianch-uan County from 1954. In 1976,the criteria of schistosomiasis endemic controlled were reached,and the infection rate of popu-lation was 0.65%and the infection rate of snails was 0.40%. In 1981,the criteria of schistosomiasis transmission controlled were reached,and the infection rate of population was 0.34%and the infection rate of snails was 1.41%. In 1993,the criteria of schis-tosomiasis transmission interrupted were reached,and the infection rate of population was 0 and the infection rate of snails was 0. There was a fluctuation in the schistosomiasis epidemic situation and snail status during the whole control duration ,but the trend was decreasing. Conclusion The time from schistosomiasis endemic controlled to transmission controlled is relatively short,but the time from transmission controlled to transmission interrupted is relatively long. In the original schistosomiasis en-demic areas,there might be some areas where there is no the disease bud there still are snails.