Olfactory and taste disorders in COVID-19: a systematic review
Bibliographic record
Abstract
The SARS-CoV-2 virus causes COVID-19, and it is responsible for the largest pandemic since the 1918 H1N1 influenza outbreak. The classic symptoms of the disease have been well defined by the World Health Organization; however, olfactory/gustatory disorders have been reported in some studies, but there are still several missing points in the understanding and in the consensus about the clinical management of these cases. To identify evidence in the scientific literature about olfactory/gustatory disorders, their clinical presentation, prevalence and possible specific treatments associated with COVID-19. A systematic review of articles published up to April 25, 2020 was performed in Medline, Cochrane Clinical Trials, ScienceDirect, Lilacs, Scopus and Google Schoolar, OpenGrey.eu, DissOnline, The New York Academy of Medicine and Reasearch Gate. Inclusion criteria: (1) Studies on patients with COVID-19; (2) Records of COVID-19 signs/symptoms, and olfactory/gustatory functions. Exclusion criteria: (1) Studies on non-human coronavirus; (2) Review articles; (3) Experimental studies (in animals or in vitro); (4) Olfactory/gustatory disorders initiated prior to SARS-CoV-2 infection. The risk assessment of bias of the selected studies was performed using the Newcastle-Ottawa scale. Six articles from the 1788 records met the inclusion criteria and were analyzed. A total of 1457 patients of different ethnicities were assessed; of them, 885 (60.7%) and 822 (56.4%) had smell and taste disorders, respectively, with women being most often affected. There were olfactory/gustatory disorders even without nasal obstruction/rhinorrhea and beginning even before the signs/symptoms of COVID-19; the recovery of smell/taste, when it occurs, usually happened in the first two weeks after COVID-19 resolution. There is evidence that olfactory/gustatory disorders are strong predictors of infection by SARS-CoV-2, and it is possible to recommend patient isolation, as early as of the medical consultation, preventing the spread of the virus. No scientific evidence has been identified for effective treatments for any of the disorders. Olfactory/gustatory disorders may occur at varying intensities and prior to the general symptoms of COVID-19 and should be considered as part of the clinical features of COVID-19, even in mild cases. There is still no scientific evidence of specific treatments for such disorders in COVID-19 disease. O vírus SARS-CoV-2 causa a COVID-19 e é responsável pela maior pandemia desde o surto de influenza H1N1 de 1918. Os sintomas clássicos da doença já foram bem definidos pela Organização Mundial da Saúde; entretanto, distúrbios olfativo-gustativos têm sido relatados em alguns estudos, mas ainda com várias lacunas no entendimento e no consenso sobre a condução clínica desses casos. Identificar evidências na literatura científica sobre os distúrbios olfativo-gustativos acerca da apresentação clínica, prevalência e possíveis tratamentos específicos associados à COVID-19. Revisão sistemática de artigos publicados até 25 de abril de 2020 nas bases de dados: Medline, Cochrane Clinical Trials, ScienceDirect, Lilacs, Scopus e Google Schoolar, OpenGrey.eu, DissOnline, The New York Academy of Medicine e Reasearch Gate. Foram critérios de inclusão: 1) Estudos com indivíduos com COVID-19; 2) Registro dos sinais/sintomas da COVID-19 e das funções olfativo-gustativa. Foram critérios de exclusão: 1) Estudos sobre coronavírus não humano; 2) Artigos de revisão; 3) Estudos experimentais (em animais ou in vitro); 4) Distúrbios olfativos-gustativos iniciados previamente à infecção pelo SARS-CoV-2. A avaliação de risco de viés dos estudos selecionados foi feita por meio da escala de Newcastle-Ottawa. Seis artigos dos 1.788 registros foram selecionados. Um total de 1.457 pacientes de diversas etnias foi avaliado; desses, 885 (60,7%) apresentaram perda do olfato e 822 (56,4%) perda do paladar, sendo as mulheres as mais afetadas. Os distúrbios olfativo-gustativos estiveram presentes mesmo sem obstrução nasal/rinorreia e com início mesmo antes dos sinais/sintomas clínicos da COVID-19; a recuperação do olfato/paladar, quando ocorre, geralmente se dá nas duas primeiras semanas após a resolução da doença. Há evidências que os distúrbios olfativo-gustativos sejam fortes preditores de infecção pelo SARS-CoV-2, podendo-se recomendar o isolamento do paciente, já a partir da consulta médica, para evitar a disseminação do vírus. Não foram identificadas evidências científicas para tratamentos eficazes para nenhum dos distúrbios. Podem ocorrer distúrbios olfativo-gustativos em intensidades variáveis e prévios aos sintomas gerais da COVID-19, devem ser considerados como parte dos sintomas da doença, mesmo em quadros leves. Não há ainda evidências científicas de tratamentos específicos para tais distúrbios na COVID-19.
Fetched live from OpenAlex and de-inverted. Abstracts are not stored in this database: the inverted indexes are 8.6 GB of the frame’s 9.3 GB of text, and the host has 13 GB free.
How this classification was reachedexpand
Full frame machine prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. The Gemma side is a direct model label for every work in the frame, read from the title-only record. The Codex side is a classifier learned from the 10,348 direct Codex labels and calibrated to design-weighted sample rates; fields without enough sample support carry no Codex call. Candidate is the union of the two sides; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels.
Distilled classifier scores by category (both heads)
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.004 | 0.014 |
| Meta-epidemiology (narrow) | 0.001 | 0.001 |
| Meta-epidemiology (broad) | 0.008 | 0.006 |
| Bibliometrics | 0.012 | 0.013 |
| Science and technology studies | 0.001 | 0.001 |
| Scholarly communication | 0.003 | 0.002 |
| Open science | 0.002 | 0.002 |
| Research integrity | 0.002 | 0.001 |
| Insufficient payload (model declined to judge) | 0.006 | 0.000 |
Machine scores (provisional)
The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.
Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.
score_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from itClassification
machine, unvalidatedMachine predicted; a candidate call from one source (direct Gemma or distilled Codex), not a consensus.
How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".