JMIR Publications

ABSTRACT

Background:

External factors may hinder Google Trends (GT)’s role as an infodemiology tool. For COVID-19, new symptoms and their searches on internet prior to world organization of health validation were previsouly described. In western country, an unexpected outbreak of cutaneous acral lesion e.g chilblains was released by the dermatologists in April.

Objective:

The aim of the study was to assess the temporality between media announcement or lockdown and online searches related to cutaneous acral lesion during COVID-19 outbreak.

Methods:

Two searches on GT including daily relative search volumes related to 1/ “toe” or “chilblains” and 2/ “coronavirus” were made from January 1st to May 16th 2020 for US, UK, France, Italy, Spain, and Germany. The ratio chilblains to coronavirus was plotted. To assess the impact of lockdown and media coverages, interrupted time series analysis were performed for each country.

Results:

During the period the ratio chilblains /coronavirus searches showed a constant upward trend. In France, Italy and UK, the lockdown was associated to a significant slope change of chilblain searches with coefficient value of 1.06  0.42, 1.04  0.28 and, 1.21  0.44 (p<0.01) respectively. After media announcement, a steep statistically significant increase was found in France, Spain, Italy and the US with coefficient values of 18.95 5.77, 31.31  6.31, 14.57  6.33, 11.24  4.93 (p<0.01), followed by with a statistically significant downward trend in France, Spain and Italy (p<0.01). Adjusted R2 values were 0.311, 0.351, 0.325, 0.305 in France, Spain, Italy and US, in favor of an average correlation between time and research volume. The correlation was weak in Germany and UK.

Conclusions:

To date chilblains link to COVID-19 remains controversial in the scientific community. However their relative search volumes on GT were highly influenced by lockdown measures and media coverage suggesting caution when using GT as pandemic surveillance tool.