tetano
Editor, Senior Moderator
Open Forum Infect Dis
. 2020 Dec 28;8(2)
faa589.
doi: 10.1093/ofid/ofaa589. eCollection 2021 Feb.
Self-Rated Smell Ability Enables Highly Specific Predictors of COVID-19 Status: A Case-Control Study in Israel
Noam Karni[SUP] 1 2 [/SUP], Hadar Klein[SUP] 3 [/SUP], Kim Asseo[SUP] 3 [/SUP], Yuval Benjamini[SUP] 4 [/SUP], Sarah Israel[SUP] 1 2 [/SUP], Musa Nammary[SUP] 1 2 [/SUP], Keren Olshtain-Pops[SUP] 5 2 [/SUP], Ran Nir-Paz[SUP] 5 2 [/SUP], Alon Hershko[SUP] 1 2 [/SUP], Mordechai Muszkat[SUP] 1 2 [/SUP], Masha Y Niv[SUP] 3 [/SUP]
Affiliations
Abstract
Background: Clinical diagnosis of coronavirus disease 2019 (COVID-19) is essential to the detection and prevention of COVID-19. Sudden onset of loss of taste and smell is a hallmark of COVID-19, and optimal ways for including these symptoms in the screening of patients and distinguishing COVID-19 from other acute viral diseases should be established.
Methods: We performed a case-control study of patients who were polymerase chain reaction-tested for COVID-19 (112 positive and 112 negative participants), recruited during the first wave (March 2020-May 2020) of the COVID-19 pandemic in Israel. Patients reported their symptoms and medical history by phone and rated their olfactory and gustatory abilities before and during their illness on a 1-10 scale.
Results: Changes in smell and taste occurred in 68% (95% CI, 60%-76%) and 72% (95% CI, 64%-80%) of positive patients, with odds ratios of 24 (range, 11-53) and 12 (range, 6-23), respectively. The ability to smell was decreased by 0.5 ? 1.5 in negatives and by 4.5 ? 3.6 in positives. A penalized logistic regression classifier based on 5 symptoms had 66% sensitivity, 97% specificity, and an area under the receiver operating characteristics curve (AUC) of 0.83 on a holdout set. A classifier based on degree of smell change was almost as good, with 66% sensitivity, 97% specificity, and 0.81 AUC. The predictive positive value of this classifier was 0.68, and the negative predictive value was 0.97.
Conclusions: Self-reported quantitative olfactory changes, either alone or combined with other symptoms, provide a specific tool for clinical diagnosis of COVID-19. A simple calculator for prioritizing COVID-19 laboratory testing is presented here.
Keywords: COVID-19; classifier; prediction; smell loss; taste loss.
. 2020 Dec 28;8(2)
faa589.doi: 10.1093/ofid/ofaa589. eCollection 2021 Feb.
Self-Rated Smell Ability Enables Highly Specific Predictors of COVID-19 Status: A Case-Control Study in Israel
Noam Karni[SUP] 1 2 [/SUP], Hadar Klein[SUP] 3 [/SUP], Kim Asseo[SUP] 3 [/SUP], Yuval Benjamini[SUP] 4 [/SUP], Sarah Israel[SUP] 1 2 [/SUP], Musa Nammary[SUP] 1 2 [/SUP], Keren Olshtain-Pops[SUP] 5 2 [/SUP], Ran Nir-Paz[SUP] 5 2 [/SUP], Alon Hershko[SUP] 1 2 [/SUP], Mordechai Muszkat[SUP] 1 2 [/SUP], Masha Y Niv[SUP] 3 [/SUP]
Affiliations
- PMID: 33604398
- PMCID: PMC7798480
- DOI: 10.1093/ofid/ofaa589
Abstract
Background: Clinical diagnosis of coronavirus disease 2019 (COVID-19) is essential to the detection and prevention of COVID-19. Sudden onset of loss of taste and smell is a hallmark of COVID-19, and optimal ways for including these symptoms in the screening of patients and distinguishing COVID-19 from other acute viral diseases should be established.
Methods: We performed a case-control study of patients who were polymerase chain reaction-tested for COVID-19 (112 positive and 112 negative participants), recruited during the first wave (March 2020-May 2020) of the COVID-19 pandemic in Israel. Patients reported their symptoms and medical history by phone and rated their olfactory and gustatory abilities before and during their illness on a 1-10 scale.
Results: Changes in smell and taste occurred in 68% (95% CI, 60%-76%) and 72% (95% CI, 64%-80%) of positive patients, with odds ratios of 24 (range, 11-53) and 12 (range, 6-23), respectively. The ability to smell was decreased by 0.5 ? 1.5 in negatives and by 4.5 ? 3.6 in positives. A penalized logistic regression classifier based on 5 symptoms had 66% sensitivity, 97% specificity, and an area under the receiver operating characteristics curve (AUC) of 0.83 on a holdout set. A classifier based on degree of smell change was almost as good, with 66% sensitivity, 97% specificity, and 0.81 AUC. The predictive positive value of this classifier was 0.68, and the negative predictive value was 0.97.
Conclusions: Self-reported quantitative olfactory changes, either alone or combined with other symptoms, provide a specific tool for clinical diagnosis of COVID-19. A simple calculator for prioritizing COVID-19 laboratory testing is presented here.
Keywords: COVID-19; classifier; prediction; smell loss; taste loss.