The otorhinolaryngological manifestations of Corona Virus Disease 2019 (COVID-19) are not much emphasized in the clinical features of COVID-19. Otolaryngologists are at great risk of getting infected with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) while they are managing COVID-19 patients in OPD and/or OR settings. In this article author analyzes the status of ear, nose, and throat (E.N.T.) symptoms and their significance in the diagnosis of COVID-19. The most common symptoms of COVID-19 reported are fever, cough, fatigue, and short breath. Common E.N.T. manifestations observed are rhinorrhea, nasal congestion, and sore throat. The E.N.T. symptoms which are observed during the asymptomatic phase of the disease are dysfunctions of smell and taste sensations. The common E.N.T. clinical features which are not specific for Covid-19 patients are rhinorrhea, nasal congestion, and sore throat. The E.N.T. manifestations which are found specific indicators of Covid-19, are dysfunctions of olfactory and taste sensations. The olfactory and gustative dysfunctions could be the only and presenting symptoms of COVID-19.
The novel Corona Virus Disease 2019 (COVID-19), caused by severe acute respiratory syndrome coronavirus 2 (SARSCoV-2 belonging to β-coronavirus), is a highly contagious zoonosis which has human-to-human spread by respiratory secretions. COVID-19 pandemic has become a global health crisis and otolaryngologists are at great occupational risk of contracting SARS-CoV-2 infection. The COVID-19 pandemic has dramatically changed the practice of otolaryngologists which have ethical implications and are formidable and distinct from other surgical fields. It has issues of public health stewardship and safety, distributive justice, and non-abandonment.
The COVID-19 which has been receiving worldwide attention due to its rapid spread and high mortality, started from Wuhan, Hubei province in China. It has rapidly swept across the world. World Health Organization (WHO) on 30 January 2020 declared COVID-19 epidemic as a public health emergency of international concern. This highly pathogenic and large-scale epidemic of SARS-CoV-2 of twenty-first century is leading to unprecedent challenges to medical profession and humanity at large.
The elderly and people with associated comorbidities usually develop complications and need mechanical ventilation. COVID-19 results in higher mortality in the elderly population in comparison to adults and children. The patients with COVID-19 infection usually present with fever, cough, breathlessness, and fatigue and a small population of patients have gastrointestinal infection symptoms.
The elderly people and patients with comorbid disorders are susceptible to infection and prone to serious life-threatening complications, which may be associated with acute respiratory distress syndrome (ARDS) and cytokine storm. Ear, nose and throat symptoms though not uncommon in COVID-19 patients, are not highlighted much in the literature. This article provides a brief and precise review of the current knowledge regarding the ear, nose and throat manifestations and their significance in the diagnosis of COVID-19 patients. The first reported physician fatality related to COVID19 was that of an otolaryngologist.
Spread / Transmission
The SARS-CoV-2 is reported to spread through droplet, aerosols, direct contact with an infected individual, fecaloral, and body fluid routes. Human-to-human spread occurs through respiratory secretions. Fecal-oral spread has also been confirmed. The main routes of transmission are droplets and close contact transmission. Asymptomatic pediatric patients are believed to serve as a reservoir for the virus. Aerosol transmission is reported to occur under the condition of long exposure to high concentrations of aerosols in a relatively closed environment. When an infected patient coughs, sneezes, breathes vigorously, or speaks loudly, the released virus can dissolve with the aerosol and become the bio-aerosols. The bio-aerosol particles ranging in size from 1.0 to 5.0 μm generally remain in the air, whereas larger particles are deposited on surfaces. Droplets of saliva thrown out during sneezing or coughing, are generally of 1 to 5 mm. They spread in a space of about 1 to 2 m from the source of infection. In contrast aerosols can travel hundreds of meters.
Majority of the patients (70%-80%) with COVID-19 are asymptomatic or mildly ill or have atypical clinical features. These patients can spread SARS-CoV-2 infection with high efficiency. These patients may be seen in otolaryngology OPD with noninfectious disease settings.
In fact, ear nose and throat symptoms of COVID-19 have not received the required attention in the literature. Asymptomatic COVID-19 patients, which constitute 70% to 80% of the patients do not have its most highlighted and putative clinical features like fever, cough, fatigue, and breathlessness. Some of these patients may have atypical symptoms such as disturbed smell and taste sensation. These patients pose a high risk to treating doctors especially E.N.T. surgeons who must therefore employ respiratory protective strategies. COVID-19 patients usually present with fever, cough, fatigue and short breath. The ear, nose and throat (E.N.T.) symptoms, which are common but not specific to Covid-19 patients, are sore throat, nasal congestion and discharge. The atypical E.N.T. symptoms, which are found to be specific indicators of COVID-19, are anosmia/hyposmia and ageusia. They could be present even before the molecular confirmation of COVID-19. Upper respiratory tract (URT) symptoms were found in the initial stages of COVID-19 and were commonly found in younger patients.
The pooled data have shown following symptoms (in descending order of frequency): fever, cough, fatigue, pharyngodynia, and nasal congestion. The symptoms of rhinorrhea and the dysfunctions of olfaction and gustation have also been reported. The associated comorbidities found are hypertension, diabetes, and coronary heart disease. Other reported Covid-19-related otolaryngologic symptoms includes facial pain and nasal obstruction.
The common E.N.T. clinical features which are not specific for Covid-19 patients are rhinorrhea, nasal congestion, and sore throat. The E.N.T. manifestations which are found specific indicators of Covid-19, are dysfunctions of olfactory and taste sensations.
The chemosensory dysfunctions (anosmia/hyposmia and ageusia/dysgeusia) are found strongly associated with Covid-19 ambulatory patients and should be considered when screening these patients. In most patients, chemosensory dysfunctions recover within weeks along with the resolution of other symptoms.
Identification of early or atypical symptoms (loss of smell and taste) of Covid-19 ambulatory patients is important as their timing and association in patients with Covid-19 can facilitate screening and early isolation of these cases which could prevent spread of the SARS-CoV-2 infection. The impairment of smell and taste were found strongly associated with Covid-19-positivity, whereas, sore throat was associated with Covid-19-negativity. These patients reported resolution of anosmia with clinical resolution of illness. The isolated sudden anosmia (ISA) should be considered as highly suspicious for COVID-19. These asymptomatic patients may not develop any further symptoms except ISA.
The smell loss is an early symptom that is associated with COVID-19 pandemic. Patients with viral upper respiratory tract infection (URTI) can have though uncommon associated olfactory loss. The patients with SARSCoV-2 infection can present to physicians with olfactory dysfunction. In acute phases of viral URTI (common cold), smell loss usually occurs as a result of nasal inflammation, mucosal edema, and nasal obstruction. These features can impede the airflow into the olfactory cleft. In most cases of URTI, this smell loss is self-limiting and usually resolve with the resolution of URTI symptoms. However, in some cases of viral URTI, the olfactory dysfunction may persist for long period (months to years) due to a more direct olfactory insult by the virus. It is not yet established whether infection with SARS-CoV-2 causes persistent smell loss. Even if SARS-CoV-2 causes persistent smell loss in some cases, then the overall prevalence of olfactory loss due to the high volume of the Covid-19 patients, could be quite large.The sudden anosmia and/or ageusia are important complaints in asymptomatic patients of COVID-19 disease. Olfactory and gustatory dysfunctions were found prevalent symptoms in European COVID-19 patients. In these COVID-19 patients, who did not have nasal discharge and stuffiness, olfactory and gustatory dysfunctions were found most prevalent symptoms. In some of the patients, olfactory dysfunction appeared before the other symptoms. Approximately half of the patients can have early recovery of olfactory dysfunction. Females were found affected more by dysfunctions of olfactory and gustatory than males.
The hearing loss in patients with Covid-19 is uncommon. COVID-19 infection can affect cochlear hair cell functions at an early stage of COVID-19 when patients are asymptomatic. In one elderly lady patient of COVID-19, coincident sensorineural hearing loss (SNHL) was noticed. No improvement in hearing loss was observed during the recovery. Brainstem involvement has been reported in Covid-19 patient and that could be the cause of SNHL. The high frequency pure-tone thresholds and the TEOAE amplitudes were observed significantly worse in COVID-19 patients.
Classification of Symptoms
On the basis of the observations made during the current review of the clinical manifestations of COVID-19, author proposes the following classification of symptoms (Table 1): General, Respiratory, Nonspecific E.N.T., and Specific E.N.T. The nonspecific E.N.T. symptoms are common in other upper respiratory tract infections also however specific E.N.T. symptoms, which may also be called atypical symptoms, can be the indicators of COVID-19 disease.
Table 1: Symptoms of COVID-19 and their Classification
The olfactory and gustative dysfunctions could be the only and presenting symptoms of COVID-19. People must be aware about these atypical symptoms (loss of smell and taste sensations) which could be indicators of COVID-19 and important in making early diagnosis so that desired protective measures could be implemented. It is not clear why only some COVID-19 patients develop ENT symptoms while others do not have any E.N.T. features. These issues need further research.
Source: Bansal M. COVID-19: An Otorhinolaryngology Perspective. International Journal of Medical Science and Diagnosis Research (IJMSDR). 2020, 4: 9-13 (NLM ID 101738825)