Madden Kenneth M, Feldman Boris
Gerontology and Diabetes Research Laboratory, Division of Geriatric Medicine, Department of Medicine, University of British Columbia, Vancouver, British Columbia, Canada.
Centre for Hip Health and Mobility, University of British Columbia, Vancouver, British Columbia, Canada.
Heliyon. 2021 Dec;7(12):e08499. doi: 10.1016/j.heliyon.2021.e08499. Epub 2021 Nov 30.
The current pandemic of Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) was first reported in Wuhan, China. Although the first case in the United States was reported on Jan 20, 2020 in Washington, the early pandemic time course is uncertain. One approach with the potential to provide more insight into this time course is the examination of search activity. This study analyzed US search data prior to the first press release of anosmia as an early symptom (March 20, 2020).
Daily internet search query data was obtained from Google Trends (September 20th to March 20th for 2015 to 2020) both for the United States and on a state-by-state basis. Normalized anosmia-related search activity for the years prior to the pandemic was averaged to obtain a baseline level. Cross-correlations were performed to determine the time-lag between changes in search activity and SARS-CoV-2 cases/deaths.
Only New York showed both significant increases in anosmia-related terms during the pandemic year as well as a significant lag (6 days) between increases in search activity and the number of cases/deaths attributed to SARS-CoV-2.
There is no evidence from search activity to suggest earlier spread of SARS-CoV-2 than has been previously reported. The increase in anosmia-related searches preceded increases in SARS-CoV-2 cases/deaths by 6 days, but this was only significant over the background noise of searches for other reasons in the setting of a very large outbreak (New York in the spring of 2020).
严重急性呼吸综合征冠状病毒2（SARS-CoV-2）当前的全球大流行首次在中国武汉被报道。尽管美国于2020年1月20日在华盛顿报道了首例病例，但大流行早期的时间进程仍不确定。一种有可能更深入了解这一时间进程的方法是检查搜索活动。本研究分析了在嗅觉丧失作为早期症状首次发布新闻稿之前（2020年3月20日）的美国搜索数据。
从谷歌趋势获取美国及各州的每日互联网搜索查询数据（2015年至2020年9月20日至3月20日）。对大流行前几年与嗅觉丧失相关的标准化搜索活动进行平均，以获得基线水平。进行交叉相关性分析，以确定搜索活动变化与SARS-CoV-2病例/死亡之间的时间滞后。
只有纽约在大流行年份与嗅觉丧失相关的术语显著增加，并且搜索活动增加与归因于SARS-CoV-2的病例/死亡数量之间存在显著滞后（6天）。
搜索活动没有证据表明SARS-CoV-2的传播比先前报道的更早。与嗅觉丧失相关的搜索增加比SARS-CoV-2病例/死亡增加提前6天，但在2020年春季纽约这样大规模疫情爆发的背景下，在因其他原因进行搜索的背景噪音中，这一现象才具有显著性。
