NEGATIVE Amazon reviews of scented candles may indicate the number of covid-19 cases in the community and could even predict infection spikes.
Viral Twitter posts have suggested that Amazon reviews for highly scented products could highlight the extent in the population of anosmia, or a loss of smell, a key covid-19 symptom. To learn more, Nick Beauchamp at Northeastern University, Massachusetts, and his colleagues analysed 9837 Amazon reviews of four best-selling scented candles produced by the brand Yankee Candle. All were posted between September 2018 and December 2021.
They noted the number of reviews that said the candles had no smell and compared them with reported covid-19 cases in the US.
The research “started out as a joke”, says Beauchamp, however, the team found a link between covid-19 cases and negative candle reviews. For every 100,000 new covid-19 cases a week in the US over the study period, the number of Yankee Candle reviews saying the product had no smell went up by 0.25 percentage points. A statistical analysis revealed this link wasn't a chance finding.
The connection also persisted despite the study covering the beginning of the omicron wave in the US, spanning December 2021 to February 2022. Omicron causes anosmia less commonly compared with previous coronavirus variants. The link also still stood after the researchers accounted for other seasonal illnesses that can affect smell. The team presented the work at the International AAAI Conference on Web and Social Media in June.
Monitoring scented candle reviews could track covid-19 cases as regular testing winds down worldwide, says Beauchamp.