Tracking waves of COVID-19 through 'no smell' complaints made on candle reviews

In an ideal world, COVID-19 tests would be so frequent and ubiquitous that it would be possible to identify all active cases, isolate them for a few days, and snuff out the pandemic like a candle at the end of a long, dark night. However, the fact that we just lived through four years of Donald Trump occupying the White House is a pretty good indicator where this world falls on the “ideal” scale. Suffice to say it’s not exactly a 10.

From the start of the pandemic, governments in the U.S. and elsewhere have looked for ways to detect COVID-19 in a situation where either it’s not possible to do enough testing or where the person in charge is deliberately suppressing the rate of testing. That’s included testing the level of viral particles in sewage, which has repeatedly resulted in wildly inaccurate claims about the percentage of the population infected.

In the pursuit of more and better ways to track the impact and scale of COVID-19, podcaster Drewtoothpastenoticed a potentially significant clue that came along with the wave of omicron cases: a “fresh wave of bad reviews for Yankee Candles.”

For the blissfully unfamiliar, Yankee Candles are a line of highly scented candles usually contained in a jar and sold on a number of large retail sites, including Amazon. It’s not surprising that the reviews of these candles would contain some single-star responses, such as this one from 2018: “Smelled Bad. Both my aunt and her caregiver remarked that all three of the candles smelled ‘cheap,’ they said that ‘they smell like Lysol’ and they're reminiscent of ‘dollar store quality candles.’ Now my aunt is stuck with three terrible smelling candles that she won't use.” The aunt in question had recently had a colostomy, and the review finishes with: “I think we can all agree that the situation must be bad if you prefer the smell of human waste to a product designed to freshen the air.”

That is a bad review. It’s also the second time that poop has made an appearance in this story.

But the recent reviews are somewhat different. Rather than complaining about the overwhelming semi-medicinal scent of these candles, the recent one stars include several that note “no scent” or “didn’t give off much smell.”

In response, political science professor Nick Beauchamp took the dates of recent reviews that rated the candles poorly because they lacked smell and placed them on a graph.

Plot of ‘no smell’ complaints for the top three Yankee Candles on Amazon.

If that chart looks vaguely familiar, it could be because of a resemblance to this one.

COVID-19 daily case rates in the United States.

Beauchamp also looked at the data another way, producing this graph showing the percentage of “no smell” reviews when compared to all reviews. This should help eliminate spikes caused by there simply being more candle purchases around the holidays as people seek innocuous gifts for relatives they barely know.

‘No smell’ reviews for the top three Yankee Candles at Amazon as a percentage of total reviews.

That graph may seem like a less than perfect match to the spikes in daily cases. However, there’s also another set of data to compare.

That seems … pretty remarkable. But remember, only about 40% of those with symptomatic COVID-19 report a loss of smell or taste. Also, complaints about Yankee Candle not smelling enough are a trailing indicator. And possibly one of the few benefits of the disease.