TY  - JOUR
AU  - Liu, Kui
AU  - Huang, Sichao
AU  - Miao, Zi-Ping
AU  - Chen, Bin
AU  - Jiang, Tao
AU  - Cai, Gaofeng
AU  - Jiang, Zhenggang
AU  - Chen, Yongdi
AU  - Wang, Zhengting
AU  - Gu, Hua
AU  - Chai, Chengliang
AU  - Jiang, Jianmin
PY  - 2017
DA  - 2017/08/08
TI  - Identifying Potential Norovirus Epidemics in China via Internet Surveillance
JO  - J Med Internet Res
SP  - e282
VL  - 19
IS  - 8
KW  - norovirus
KW  - Internet surveillance
KW  - disease prediction
AB  - Background: Norovirus is a common virus that causes acute gastroenteritis worldwide, but a monitoring system for norovirus is unavailable in China. Objective: We aimed to identify norovirus epidemics through Internet surveillance and construct an appropriate model to predict potential norovirus infections. Methods: The norovirus-related data of a selected outbreak in Jiaxing Municipality, Zhejiang Province of China, in 2014 were collected from immediate epidemiological investigation, and the Internet search volume, as indicated by the Baidu Index, was acquired from the Baidu search engine. All correlated search keywords in relation to norovirus were captured, screened, and composited to establish the composite Baidu Index at different time lags by Spearman rank correlation. The optimal model was chosen and possibly predicted maps in Zhejiang Province were presented by ArcGIS software. Results: The combination of two vital keywords at a time lag of 1 day was ultimately identified as optimal (ρ=.924, P<.001). The exponential curve model was constructed to fit the trend of this epidemic, suggesting that a one-unit increase in the mean composite Baidu Index contributed to an increase of norovirus infections by 2.15 times during the outbreak. In addition to Jiaxing Municipality, Hangzhou Municipality might have had some potential epidemics in the study time from the predicted model. Conclusions: Although there are limitations with early warning and unavoidable biases, Internet surveillance may be still useful for the monitoring of norovirus epidemics when a monitoring system is unavailable. 
SN  - 1438-8871
UR  - http://www.jmir.org/2017/8/e282/
UR  - https://doi.org/10.2196/jmir.7855
UR  - http://www.ncbi.nlm.nih.gov/pubmed/28790023
DO  - 10.2196/jmir.7855
ID  - info:doi/10.2196/jmir.7855
ER  -