Purpose The study aimed to determine the incidence and long-term evolution of COVID-related olfactory (OD) and gustatory (GD) dysfunction, the recovery timeline, and the association with other symptoms. The secondary objective was to identify the predictive clinical factors for the evolution of these symptoms. Methods A prospective case–control study was conducted from March 15 to October 15, 2020, in health workers with COVID-19 related symptoms in a tertiary care hospital. 320 patients were included after 6 months of follow-up: 195 in the case group and 125 in the control group. Olfactory dysfunction (OD), dysosmia, and gustatory dysfunction (GD) onset and recovery rate after 6 months follow-up are analyzed in both groups. Results There were 125 (64.1%) in case group patients with OD and 118 (60.5%) with GD. Total or partial recovery OD and GD was found in 89%, mainly in the first 2 months. In the control group, there were 14 (11.2%) patients with OD and 33 (26.4%) patients with GD, with 100% of total/partial recovery. Conclusion In both groups, OD and GD showed high-resolution rates during the first two months after the onset of symptoms. Nevertheless, 11% of the case group patients did not show any recovery, and the partial resolution was present in 30% of our patients, at the 6 months follow-up. We found a high correlation between OD and GD, both in the appearance of symptoms and in their recovery. Nasal obstruction and dyspnea have been identified as risk factors for the persistence of symptoms.

To evaluate the incidence of certain symptoms in a population of health workers exposed to coronavirus disease 2019 patients. Study Design: Case-control study. Methods: The study was conducted at a tertiary care hospital from March 1 to April 7, 2020. Health workers with suspected coronavirus disease 2019 (COVID-19) infection were included. The presence of COVID-19 was detected by using real-time polymerase chain reaction (RT-PCR) methods. Positive and negative RT-PCR patients were used as case and control groups, respectively. This study analyzed the incidence of COVID-19 symptoms in both patient groups. Visual analog scales were used for selfassessment of smell and taste disorders, ranging from 0 (no perception) to 10 (excellent perception). Results: There were 215 (60.6%) patients with positive RT-PCR and 140 (39.4%) patients with negative RT-PCR. The presence of symptoms such as hyposmia hypogeusia, dysthermia, and cough were strongly associated with a positive RT-PCR. The association of cough and subjective hyposmia had 5.46 times higher odds of having a positive test. The receiver operating characteristic (ROC) analysis showed that a fever higher than 37.45 C resulted in sensitivity and specificity of 0.65 and 0.61, respectively. A total of 138 cases (64.1%) and 114 cases (53%) had subjective hyposmia and hypogeusia, respectively. The 85.4% of these patients recovered olfactory function within the first 14 days of the onset of the symptoms. Conclusion: There is a significant association between positive RT-PCR and subjective hyposmia. The association of subjective hyposmia and cough increase significantly the odds of having a positive RT-PCR. The measurement of fever as the only method for screening of COVID-19 infection resulted in a poor association.

Persistence of residual symptoms 1 month after the acute BPPV can be associated with certain risk factors that should be taken into consideration (age, number of repositioning maneuvers needed, anxiety and/or depressive disorders). These patients could benefit of treatment with vestibular rehabilitation.

In addition to the recovery of the vestibulo-ocular reflex, the reduction of latency, velocity and the organization of compensatory saccades play a role in vestibular compensation.