Get to know your Covid-19 enemy

How you may be infected

A typical Covid-19 infection begins with a close contact with an infected person as that contact exposes you to a possible infection. It is not certain that you will be infected. That depends on many factors, including the viral load, how well you are protected and how good is your own immunity.

Close contact is a very specifically defined term. It does not apply to you if you just happened to walk past a known Covid-19 patient, or even if you happened to talk to the patient for a brief time when both are wearing masks. See the image before for its definition as applied to HCW.

For a more general definition of a close contact encounter with a Covid-19 patient, take a look at the bottom section of this image below.

(PUI stands for Person Under Investigation)

Generally, the rationale is that the longer you are exposed to the patient, the higher is your risk of getting the infection. As a general guideline, the recommended cut off point for the encounter is taken as 15 minutes, i.e. if your encounter lasted less than 15 minutes, you are less likely to be infected. This is, however, not absolute, and should be assessed together with other factors, such as whether face masks were worn, there was any cough or sneeze, or vigorous talking, and the infectious period of the patient.

A viral load is the amount of virus present. The bigger the viral load, the more viruses are present, and therefore the higher the risk of infection. Viral load is determined by how much viruses are in the body of the infected person that you are in contact with at the time of the close contact. It is also determined by whether the infected person sneezes or coughs in your presence, or whether he or she talks to you, and how long. The duration of your exposure is another factor to consider. The longer you are exposed, the higher the risk of infection. Therefore, minimise your contact with other people, and if you cannot avoid the contact, make it as brief as possible.

On the other hand, the further away you are from the infected person, the less likely you are of getting the infection. This is why physical distancing is so important.

How the virus may get into your body

Fortunately, the virus cannot enter your body through the skin. Its most common route of entry into the body is through the eyes, the nose and the mouth. That is why it is important to wear your mask. Your mask protects your nose and mouth, preventing the virus from entering your body. Nose swabs and throat swabs often yield more positive results from the nose than the throat, suggesting that the nose may be a more important entry point for the virus compared to the mouth. Therefore, make sure you wear your mask properly and cover both the nose and the mouth. For added protection, especially for HCW (healthcare workers) who are frequently in contact with patients, a face shield is recommended to protect the eyes as well.

So, whether you get infected or not depends on how well you protect yourself. Wearing a mask greatly reduces the risk. If the infected person also wears a mask, the risk even even smaller.

What happens when the virus gets into the body

Once the virus gets into your body, it incubates for about 5 days, multiplying in your body and increasing the viral load.

Symptoms typically appear about day 5 of the infection. Symptoms are fever, body ache, cough, and general feeling of unwell (often indistinguishable from other viral infections like flu and dengue). In severe cases, there is difficulty in breathing.

You are infectious about 1 – 2 days BEFORE your first symptom appears, so you may not know it and may spread it to others unintentionally. The infectious period may last 10 days, i.e. day 3 to day 13. This is the rationale for the 14 day quarantine.

However, we must also bear in mind that some Covid-19 infections may present atypically, meaning they differ from the above typical infection. Some may actually last longer, and become more severe, even deadly.

How to protect yourself from infection

Very important – follow the SOP strictly. Do not be negligent. Do not take this lightly, yet at the same time there is no need to panic. Be rationale in your approach.

  1. Wear your face mask properly

2. Wash your hands regularly and thoroughly, especially before you touch your face or after you have touched your mask. Always regard your mask as though it is contaminated with the virus. In this way, you will be more careful when you handle your mask. Also, dispose your mask properly and safely.

3. Practice physical distancing. The further you are, the less likely for you to be infected. The minimum recommendation is 6 feet apart.

4. Regard everyone as a potential spreader. Therefore, limit your contact with others. Avoid unnecessary contact. Where contact is unavoidable, make it as brief as possible.