Loss of smell or taste has been added to the list of COVID-19 symptoms, according to the revised clinical management protocols released by the Union Health Ministry on Saturday.
The ministry said that coronavirus-infected patients reporting to various COVID-19 treatment facilities have been reporting symptoms like fever, cough, fatigue, shortness of breath, expectoration, myalgia, rhinorrhea, sore throat and diarrhea.
They have also complained of loss of smell (anosmia) or loss of taste (ageusia) preceding the onset of respiratory symptoms.
Older people and immune-suppressed patients in particular may present with atypical symptoms such as fatigue, reduced alertness, reduced mobility, diarrhoea, loss of appetite, delirium, and absence of fever, the ministry said.
Children might not have reported fever or cough as frequently as adults.
The US's national public health institute, the Centers for Disease Control and Prevention (CDC), had in early May incorporated "a new loss of taste or smell" in the list of COVID-19 symptoms.
According to the data from Integrated Health Information Platform and Integrated Disease Surveillance Programme, portal case investigation forms for COVID 19 (n=15,366), the details on the signs and symptoms reported are (as on June 11), fever (27%), cough (21%), sore throat (10%), breathlessness (8%), Weakness (7%), running nose (3%) and others 24%.
According to the health ministry, people infected by the novel coronavirus are the main source of infection.
Direct person-to-person transmission occurs through close contact, mainly through respiratory droplets that are released when the infected person coughs, sneezes, or talks.
These droplets may also land on surfaces, where the virus remains viable. Infection can also occur if a person touches an infected surface and then touches his or her eyes, nose, or mouth.
The median incubation period is 5.1 days on average with a range of anywhere from 2 to 14 days. The precise interval during which an individual with COVID-19 is infectious is uncertain.
As per the current evidence, the period of infectivity starts 2 days prior to onset of symptoms and lasts up to 8 days.
The extent and role played by pre-clinical/ asymptomatic infections in transmission still remain under investigation.