The COVID-19 pandemic is one of the most serious challenges facing the world today. Global leaders are describing it as the worst health crisis for a century. As the disease rapidly spreads throughout the world, it’s important to keep informed of the facts behind the disease, how it transmits, what are the symptoms and what you can do to help protect yourself and those around you.
- COVID-19 is a fast-growing global pandemic that requires immediate action from everyone
- It is caused by a virus of the coronavirus family and primarily infects the lungs
- The majority of infected individuals (~80%) only develops mild symptoms, usually associated with colds, like fever, tiredness and dry cough
- About 1 in every 5 cases lead to serious respiratory conditions like pneumonia
- People who are older or have pre-existing medical conditions are at higher risk of developing serious symptoms
How did we get there?
On March 11th, 2020, the World Health Organization (WHO) declared the novel coronavirus (named SARS-CoV-2) and the disease that causes it (COVID-19) as a global pandemic, having considered its fast and world-wide spread.
The first reported cases of COVID-19 came in December 2019 from the Chinese city of Wuhan in the Hubei province, but quickly started to spread to other regions of China and several East Asian countries like Japan, South Korea, Taiwan and Singapore.
By February 2020, the disease had already spread to other countries around the globe, with many countries still suffering large increases in the number of infections and deaths related to the virus.
What is COVID-19?
The SARS-CoV-2 virus which causes COVID-19 belongs to a family of viruses called coronaviruses, which are known to infect birds and mammals.
Other types of coronaviruses include the Middle East respiratory syndrome-related coronavirus (MERS-CoV) and the Severe acute respiratory syndrome coronavirus (SARS-CoV), which have previously caused outbreaks in several parts of the world. Coronaviruses are also responsible for ~15% of cases of the common cold.
While we’re still learning about SARS-CoV-2, genetic comparison of the human virus with those of other species revealed that it was likely passed on to humans from bats.
It is also likely that before it was able to infect humans, the virus passed through an intermediate animal reservoir, such as the armadillo-like pangolin, where it evolved the features to be able to spread more easily between people.
How does it transmit between people?
The main mode of transmission is through so-called respiratory droplets, which exit a contaminated person when they cough, sneeze or exhale. The virus may then pass to another person if they come in either direct contact with these droplets, by being too close to an infected person, or indirect contact, by touching a contaminated surface.
The virus may remain active outside of the body for up to 9 days, so it’s important to take precaution to disinfect your hands or any surface that you feel might have come in contact with an infected person at all times.
After entering the body, it infects several organs including the intestines, the spleen and the lungs. Proteins on the outside of the virus (the ones that gives coronaviruses their spikey form), first attach themselves to receptors on the outside of a host cell. At this point, the virus can merge with the cell’s membrane and release its genetic content. Once inside, it takes control of the cell’s machinery to replicate into many more copies of itself, often gaining small mutations in the process. The replicated viruses are then released from the host cell where they’ll be able to infect many more.
In the lungs, where it can cause the most dramatic effect, a fight between the body’s immune system and the virus can lead to damage of the lung’s lining and make way for bacterial infections that can cause serious respiratory illnesses, like pneumonia.
What are the symptoms for COVID-19?
The most common symptoms are fever, tiredness, and dry cough, while some people might also develop aches and pains, nasal congestion, runny nose, sore throat or diarrhoea.
Most people who get infected (~80%) recover from the condition without the need for special treatment, but around 1 in every 5 cases become seriously ill and may require hospital care.
It’s important to know that as with most infections, there’s a delay between when a person gets infected and starts showing symptoms, known as the incubation period. With COVID-19, this period seems to be between 2 to 14 days. An infected person might still be able to infect other people during this period, although the WHO states that that risk is lower.
What do we know about risks and risk groups?
There are still a lot of unknowns about this disease, but it appears that older people (>60 years old) and persons with pre-existing medical conditions like high blood pressure, heart disease, lung disease, cancer or diabetes, tend to develop more severe symptoms. If you’re included in one of these risk groups, you should take extra precautions to reduce your risk of infection.
What can I do to protect myself and others around me?
The first thing you should do is knowing the recommendations that are currently being given by your local authorities and health officials. Conditions like how the infection is spreading, the pressure on the health-care system and prevention tactics might differ between countries or regions, so it’s always best to stay informed about the situation in your region
However, some general guidelines apply everywhere where there are concerns:
- Wash your hands often for 20 seconds with soap and water, or alcohol-based products
- Avoid touching your face
- Maintain at least 1 m (3 feet) distance between you and anyone who is coughing or sneezing
- Follow good respiratory hygiene, covering your mouth and nose when you cough or sneeze with a tissue and washing your hands immediately
- Stay at home if you feel unwell, and seek out medical attention if you have a fever, cough and difficulty breathing.
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