The Doctors of the Therapeutic Clinic of the Medical School of the National and Kapodistrian University of Athens, Theodora Psaltopoulou, Eleni Koromboki and Thanos Dimopoulos (Rector of EKPA) answer frequently asked questions about COVID-19 disease
What causes SARS-CoV-2 coronavirus?
SARS-CoV-2 coronavirus causes COVID-19 disease which can have both short-term and long-term complications. The disease usually starts with mild symptoms (fever, nausea, cough) but can eventually affect the function of the lungs, liver, kidneys and even the brain.
How is the coronavirus transmitted?
The virus is usually transmitted airborne, after close contact with an infected person, through speech, coughing, sneezing. It spreads easily between people less than one and a half meters away. An infected person can transmit the virus even before they show symptoms. More rarely, the virus can be transmitted from surfaces, such as by touching an infected object such as a door knob.
When do the first symptoms appear?
Once the virus enters the body it usually settles in the cells of the nasopharynx and oropharynx. The virus invades healthy cells and begins to reproduce. This procedure can take one to two weeks, without the person necessarily showing symptoms. Symptoms in most people are limited to the upper respiratory tract.
How does COVID-19 disease manifest itself?
The first symptoms usually include fever, headache, sore throat and dry cough. In addition, shortness of breath, myalgias, unusual fatigue, loss of taste or smell, nasal congestion, nausea or diarrhea may occur. The degree of onset of symptoms varies from person to person.
What are the complications of COVID-19?
Usually, if the immune system is unable to fight off the infection in the first week, the virus can travel to the lungs causing pneumonia. Pneumonia leads to difficulty breathing due to a drop in oxygen in the blood. Most people recover within one to two weeks but the recovery process can take longer. ΄
However in some patients pneumonia can worsen rapidly leading to respiratory distress syndrome (ARDS). The tiny, thin air sacs that carry oxygen to the blood and are called alveoli are filled with a mucous material. Chest x-ray and CT scan may show that large areas in the lungs have been occupied and no air is entering. Blood oxygen levels fall dangerously and in some cases mechanical ventilator support is needed. We now know that the deterioration in patients with COVID-19 is not only due to damage to the lungs but also to an immune system reaction called “cytokine cataract”. This immune reaction can lead to a drop in blood pressure, multiorgan failure and vascular damage.
Apart from pneumonia, what other complications can COVID-19 cause?
COVID-19 can affect almost all organs and is therefore considered a “multisystemic disease”.
Serious heart complications can occur, especially in patients with serious illnesses, such as arrhythmias, cardiomyopathy, acute myocardial damage, heart failure, vascular complications. In severely ill patients, blood clots may form in the blood vessels causing a pulmonary embolism or stroke.
COVID-19 also appears to cause symptoms in the brain such as disturbances of consciousness, seizures and strokes. About half of patients treated for COVID-19 have elevated liver enzymes, indicating liver damage, which may be the result of an interaction between the effects of the virus, medication, and an immune system disorder.
Kidney damage is common in patients with severe COVID-19 disease. Medication, a drop in blood pressure, a disorder of the immune system and the underlying diseases contribute to the appearance of manifestations by the kidneys.
About one-third of patients treated for COVID-19 develop conjunctivitis. This is due to the irritation of the eyes by the virus.
Can very mild or asymptomatic patients with COVID-19 be harmed?
There are studies that show that up to 40% of people infected with coronavirus are asymptomatic, ie do not show symptoms. However, even in these individuals the virus can cause damage to the lungs as revealed by x-rays and axial thorax.
.
