‘Zero scent’: could negative reviews of smelly candles hint at a Covid surge?

There is indeed a correlation between Covid cases and the number of reviews complaining that Yankee Candles don't have a smell, research shows

Yankee Candle calls itself America's favorite brand of premium scented candles", and offers over 600 fragrances, like Spiced pumpkin" and Warm apple pie" designed to fill your living room with homey holiday vibes.

Days before Thanksgiving 2020, a Twitter user pointed out a sharp rise in negative reviews complaining the famously pungent candles had no smell. Could it be a hidden sign of the Covid wave, the user wondered? In total, the candles have well over 100,000 reviews on Amazon - a potentially rich trove of epidemiological data.