Table Lag correlation coefficients and p values between Internet search data and daily new laboratory-confirmed/suspected COVID-19 cases, China, January–February 2020 Days earlier Google Trends Baidu Index Sina Weibo Index Coronavirus p Pneumonia p Coronavirus p Pneumonia p Coronavirus p Pneumonia p New laboratory-confirmed cases 0 0.176 0.370 −0.035 0.861 0.021 0.917 0.129 0.513 0.106 0.593 0.109 0.582 1 0.324 0.093 0.122 0.537 0.160 0.416 0.265 0.172 0.202 0.303 0.190 0.332 2 0.455 0.015 0.271 0.164 0.299 0.122 0.411 0.030 0.346 0.072 0.298 0.123 3 0.561 0.002 0.388 0.041 0.406 0.032 0.516 0.005 0.431 0.022 0.408 0.031 4 0.672 < 0.001 0.505 0.006 0.529 0.004 0.641 < 0.001 0.498 0.007 0.470 0.012 5 0.779  < 0.001 0.606 0.001 0.624 < 0.001 0.722  < 0.001 0.562 0.002 0.553 0.002 6 0.850  < 0.001 0.712  < 0.001 0.706  < 0.001 0.808  < 0.001 0.679 < 0.001 0.668 < 0.001 7 0.902  < 0.001 0.777  < 0.001 0.750  < 0.001 0.861  < 0.001 0.751  < 0.001 0.754  < 0.001 8 0.944  < 0.001 0.835  < 0.001 0.823  < 0.001 0.902   < 0.001 0.829  < 0.001 0.817  < 0.001 9 0.958   < 0.001 0.878  < 0.001 0.887  < 0.001 0.892  < 0.001 0.876  < 0.001 0.872  < 0.001 10 0.953  < 0.001 0.893   < 0.001 0.928  < 0.001 0.873  < 0.001 0.921  < 0.001 0.899   < 0.001 11 0.924  < 0.001 0.845  < 0.001 0.925  < 0.001 0.786  < 0.001 0.917  < 0.001 0.875  < 0.001 12 0.857  < 0.001 0.818  < 0.001 0.933   < 0.001 0.715  < 0.001 0.944   < 0.001 0.875  < 0.001 13 0.815  < 0.001 0.762  < 0.001 0.908  < 0.001 0.609 0.001 0.916  < 0.001 0.812  < 0.001 14 0.783  < 0.001 0.697 < 0.001 0.858  < 0.001 0.496 0.007 0.885  < 0.001 0.733  < 0.001 New suspected cases 0 −0.003 0.989 −0.372 0.073 −0.309 0.142 −0.091 0.671 −0.279 0.187 −0.309 0.142 1 0.246 0.246 −0.116 0.590 −0.068 0.753 0.141 0.511 −0.078 0.716 −0.103 0.630 2 0.413 0.045 0.104 0.630 0.125 0.560 0.346 0.098 0.089 0.680 0.050 0.818 3 0.614 0.001 0.312 0.138 0.352 0.091 0.551 0.005 0.253 0.233 0.248 0.243 4 0.768  < 0.001 0.514 0.010 0.538 0.007 0.697 < 0.001 0.431 0.035 0.383 0.065 5 0.832  < 0.001 0.687 < 0.001 0.670 < 0.001 0.816  < 0.001 0.520 0.009 0.501 0.013 6 0.912   < 0.001 0.771  < 0.001 0.725  < 0.001 0.895  < 0.001 0.672 < 0.001 0.670 < 0.001 7 0.933  < 0.001 0.850  < 0.001 0.830  < 0.001 0.914  < 0.001 0.813  < 0.001 0.872  < 0.001 8 0.875  < 0.001 0.960   < 0.001 0.906   < 0.001 0.926   < 0.001 0.924   < 0.001 0.907   < 0.001 9 0.787  < 0.001 0.865  < 0.001 0.882  < 0.001 0.850  < 0.001 0.883  < 0.001 0.899  < 0.001 10 0.744  < 0.001 0.827  < 0.001 0.841  < 0.001 0.766  < 0.001 0.818  < 0.001 0.832  < 0.001 11 0.671 < 0.001 0.770  < 0.001 0.790  < 0.001 0.698 < 0.001 0.781  < 0.001 0.802  < 0.001 12 0.544 0.006 0.693 < 0.001 0.686 < 0.001 0.559 0.005 0.697 < 0.001 0.683 < 0.001 13 0.482 0.017 0.578 0.003 0.583 0.003 0.454 0.026 0.622 0.001 0.600 0.002 14 0.497 0.013 0.448 0.028 0.547 0.006 0.288 0.173 0.609 0.002 0.550 0.005 Shaded text: high correlation with r > 0.7. Text in italics: highest correlation.