Written by Daniela Chatlani
The WHO (World Health Organisation) declared the COVID-19 virus to be a pandemic on 11th March 2020. The internet is the source that most people are referring to during the crisis. While there are reliable sources, there are also sources that hold misinformation and it can be seen that some people are still struggling to differentiate between the two. But what is actually the Coronavirus?
Coronavirus is the name given to a family of viruses. This particular strain at the centre of this pandemic was discovered in 2019 and is known as SARC-CoV-2. The disease that is caused by this virus is known as COVID-19. However, Coronaviruses usually don’t cause severe symptoms (e.g. high fever, shortness of breath) in humans but only mild symptoms (e.g. runny nose, sore throat, cough, congestion). As can be seen, the symptoms normally given sound very similar to the common cold, however, these two are unrelated as the common cold is caused by rhinovirus, which comes from a different family of viruses. COVID-19 isn’t the first strain to give fatal symptoms. The SARS outbreak in 2002 was also part of the Coronavirus family.
COVID-19 has been reported by the WHO to have a fatality rate of 3.7%. However, this could actually, in fact, be lower as there may be many asymptomatic carriers of the virus who continue living their lives normally without reporting.
How does SARS-CoV-2 cause disease?
Viruses cannot live on their own, they require a living host. The SARS-CoV-2 attaches itself to the cells, usually in the lungs and enters them. In the cell, the virus is able to replicate, using the cell’s own machinery, and create more copies of itself. The viruses are then released from the cell, destroying it in the process.
The body can detect damage being done to its cells and so an inflammatory response occurs in the region of infection. As a result of the inflammation, the capillaries surrounding the infected site will become more dilated, stretching the cells making up the capillaries, and forming spaces between the cell. Consequently, the capillaries become more porous and so plasma will flow out and fill the space between the lung tissue and the capillaries. The fluid surrounding the lung tissue will cause it to compress. As a result, air cannot fill the lungs properly and so the person will experience shortness of breath and trouble with breathing.
The inflammation in the lungs will cause two things to happen. Firstly there is the destruction of viruses but also of other cells in the lung. Debris will settle in the lung which the body tries to get rid of by excessive coughing. Secondly, the chemicals released during inflammation will travel to the brain and cause it to raise body temperature, resulting in fever.
In severe cases, sepsis may occur. During sepsis, the blood pressure drops severely and so organs lose their blood supply, resulting in multi-organ failure and death.
Overall the most common symptoms seen in COVID-19 patients are:
- Fever
- New dry cough
- Shortness of breath
- Fatigue
- Muscle pain
- Headache
Some less common symptoms reported are:
- Diarrhoea
- Runny nose
- Nausea
Prevention of COVID-19
As the old saying goes, prevention is better than cure. The COVID-19 virus has a reproductive ratio of 2-3, meaning an infected person can infect 2-3 people they come into contact with. This can be decreased with proper preventative measures.
- Wash your hands frequently: The virus can spread via the faecal-oral route, meaning that after going to the bathroom, the virus can be on your hands which can infect someone. It is therefore extra important to wash your hands after using the bathroom
- Maintaining social distance: Stand at least 1 metre away from any person who is coughing. The virus can also be spread through sneezing and coughing, up to 1 metre away.
- Avoid touching eyes, nose and mouth: The virus can enter from these areas
- Cough or sneeze into your elbow: This prevents the virus from travelling in the air
- If you have been abroad or have come into contact with someone who has been abroad, please quarantine yourself for 14 days: If you have been infected the symptoms may take up to 14 days to start manifesting
