Smell Test Now

Around March 20, there was this letter from Claire Hopkins and Nirmal Kumar, professors of medicine in the UK noticing that COVID-19 patients were reporting a loss of smell. News reports quickly followed.

Today, Michael Lewis made the argument that this symptom could be used to screen those for isolation. I wondered if you could see it in Google Trends numbers.

Here is a graph dump of what I found for search terms of “can’t smell” and “sense of smell” across some English speaking countries.

The data shows something. The question is what. One possibility is that the news reports caused people to Google these terms. If you look closely in, say, New York, the spike in searches was in the week prior to March 20. But this is weekly data so it is hard to tell. Daily data would be better.

Let’s drill down and focus on the last 30 days.

Other states don’t have enough information for a clear sample.

At the moment, the dominant hypothesis is that the searches may have been stimulated by the news rather than symptoms. However, more fine-grained and unscaled Google data could reveal something more — especially when mapped to localised outbreaks. Unfortunately, Google correlate isn’t available any more so that is hard to explore too.

Anyhow, consider this post a general call for Google to get the data and explore it.

If this is a symptom, it would be good to know. Then we can use it to help move out of isolation.

Update: Here is Italy. Notice that it begins well before the March 20 news.

Was given a pointer that if I trend the topic “Anosmia” I would get better cross country results as Google pools related searches together. Here is the graph dump for that. Still a potential news effect but Italy is interesting.

This gives another sense. Include Ageusia (loss of taste).