Coronavirus Disease-19 Home A-Z Health Information Health Library A-Z Coronavirus Disease-19 Overview COVID-19 is caused by the novel coronavirus SARS-CoV-2 belonging to the coronavirus family, which also includes viruses responsible for common cold and more severe diseases like severe acute respiratory syndrome (SARS) and Middle East respiratory syndrome (MERS). The virus mainly targets the respiratory system, but its effects can be systemic, i.e., impacting multiple organs. Causes and Risk Factors The infection spreads mainly when an infected person coughs, sneezes, or talks and spreads the respiratory droplets. Aerosol (liquid particles suspended in air) transmission is possible in poorly ventilated spaces. Further, indirect transmission can also occur through contaminated surfaces. Symptoms Patients usually present generalised symptoms, such as fever, chills, cough, fatigue, and loss of taste or smell; however, severe symptoms, such as difficulty in breathing and chest pain are also observed in some cases. Older adults or individuals who already have underlying medical conditions such as diabetes or high blood pressure are at greater risk of serious illness.Individuals who do not present any symptoms but test positive for COVID-19 are termed asymptomatic. Individuals who go on to develop symptoms are considered presymptomatic. Both types of individuals are capable of spreading COVID-19 to others.COVID-19 may be subdivided into mild, moderate, severe, or critical illness:Mild COVID-19: The ability of lungs to transport oxygen to the body is not affected.Moderate COVID-19: The lungs work properly but there are indications that the infection has deeply penetrated them.Severe COVID-19: The lungs don't work correctly, and the affected individual needs oxygen and medical help.Critical COVID-19: The lungs and the respiratory system have failed and the whole body has been affected as a result.Get emergency help right away for any of these symptoms:Inability to catch your breath or there are problems in breathingSkin, lips or nail beds turn pale, grey or blueTrouble staying awake or waking upConstant chest painNew confusion Diagnosis Diagnostic tests include:PCR test: the gold standard due to its high sensitivity in detecting viral RNAAntigen test: offers faster results but are less accurateHealthcare systems play a pivotal role through preparedness and developing protocols for handling such patients. This ensures effective communication and education to combat misinformation and promote health guidelines. Treatment Treatment for COVID-19 varies based on the severity of the case. Mild cases often require self-isolation and symptomatic treatment. Moderate to severe cases may require isolation and treatment with antiviral medications like remdesivir, monoclonal antibodies for high-risk patients, anti-inflammatory drugs like dexamethasone for severe inflammation, and oxygen therapy for those with low blood oxygen levels. Critical cases might need mechanical ventilation.Post-COVID/Long COVID:Post-COVID care addresses long-term symptoms known as Long COVID, which can include fatigue, respiratory issues, and cognitive difficulties. This requires a multidisciplinary approach involving pulmonologist as centre point with good supportive care and dedicated physiotherapy department all under one roof, to provide the best possible care making a complete recovery seemingly possible.