Anosmia, a Hidden Sign for COVID-19? A Case Report and Literature Review

Abstract Background The coronavirus disease 2019 (COVID-19) is an ongoing viral pandemic that is actively affecting 210 countries worldwide, with a total of more than 1.5 million cases and 106 000 deaths. Symptoms associated with COVID-19 are mainly fever, cough, dyspnea and sore throat. The current indication for COVID-19 testing includes presence of these symptoms with a positive history of travel to affected countries or contact with COVID-19 patients. Anosmia has been recently reported anecdotally over the past weeks as an emerging symptom of the COVID-19 but has yet to gain recognition as a symptom for COVID-19 by the World Health Organization (WHO) and Centre for Disease Control and Prevention (CDC). This case report highlights a case of isolated sudden onset of anosmia as a presenting symptom of COVID-19 and relevant literature review supporting the incidence of anosmia in COVID-19. This is a first case report of anosmia in COVID-19 occurring in pregnancy.Case Presentation A 30-year-old pregnant lady at 11 weeks of gestation presented with sudden onset of anosmia for one day with no other accompanying symptoms. She had just recovered from a mild cold a day prior to the development of anosmia. She had a history of travel by land to Singapore 14 days prior to onset of anosmia. There was no known close contact with a COVID-19 patient or attended any mass gatherings prior to development of her symptom. She underwent nasopharyngeal and oropharyngeal swab sampling which was then tested using reverse transcription polymerase chain reaction (RT-PCR) method and confirmed infection with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2).Conclusion Clinicians should be aware regarding anosmia as a presenting symptom of COVID-19 especially in the presence of risk factors such as travel to affected countries and having close contact with COVID-19 positive patients. If testing is not done, these patients should be advised for home quarantine to reduce the risk of transmission. Healthcare workers must always adhere to infection control and prevention protocol as well as personal protective equipment.