COVID-19 Pathophysiology?

From Infection, to Reproduction to disease.

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COVID-19 Pathophysiology?

Reproduction, pathophysiology, & spread.

I hope you read through the prior lesson carefully and thereby learnt what the COVID-19 virus is and an understanding of the basics of how viruses cause diseases. If not, please go back and study Lesson 1 Principles of COVID-19 disease, and Lesson 2 What is Coronavirus COVID-19, and then come back here.

How viruses reproduce & spread?

Viruses do not reproduce like other organisms. There are no male & female viruses. Viruses need a living organism (animals, humans) which have living cells in them (called hosts), into which viruses enter and then reproduce by use of the genetic material in these hosts and then continue to proliferate and damage the target organ.

Spread of viruses between the human population happens via any medium of common contact between two or more people: such as air, water, plants, animals, parasites etc.

How viruses damage organs and cause disease?

Here is the sequential process of how a virus reproduces, spreads and damages a target organ.

There are 7 important biochemical processes involved in the replication of a virus once it enters a living organism:

1. Adsorption

This is the very first step. The virus first moves into the human body and adsorbs to the first layer of immunity – the mucous membrane.

If the immunity of the individual is strong (or adapted to the specific virus), the virus is destroyed at this layer itself and eliminated. If the immunity is not strong then the virus passes through this barrier and moves on to step 2 – Attachment.

Quick insight: People having low vitamin C & D have weak immunity at the mucous membrane level which thereby puts them at risk to allow the virus to enter into the target organ. Patients with chronic disease in most cases have low Vitamin C & D, including deficiencies in other essential nutrients.

2. Attachment

Here the virus attaches to the target organ by attaching to the specific receptors of the target organ cell, which thereby allows it entry into the cell – step 3.

In the case of the novel covid-19 virus, once it passes through the mucous membrane (first immunity barrier) of  the respiratory system, it attaches to the wall of the type II pneumocytes (lung cells) by its spike proteins called the S-spike to the receptor called the ACE-2.

3. Entry

Once the virus attaches/binds to the cell surface receptor (lung cell in case of COVID-19), it then is allowed entry into the cell.

The best analogy for comprehension of this step is a door-lock-key-entry analogy. – Viruses have a protein coat with spike proteins (like antennas) on their surface which function like keys with a specific pattern, and the organ-cells have receptors on their surface which function like locks with a specific pattern. If any virus has the precise key pattern (spike proteins) to attach to the lock of the organ cell (receptors), it can then get entry into the cell.

4. Uncoating

After entry, the process of uncoating takes place where the viral protein coat (outer protein coat-layer of the virus) is removed by enzymes in the cell. This process of uncoating exposes the genetic material of the virus which in most cases is an RNA (ribo-nucleic acid).

5. Transcription/ mRNA Production (Genetic copying of the virus)

The viral RNA is then used by a polymerase enzyme (an enzyme inside the cell used for building proteins for cellular regeneration) to synthesize new RNA strands of the called mRNA (messenger ribonucleic acid).

The newly synthesized RNA strands (virus gene) are then further used to form the genomic components of the newer copies of the virus which are done in step 6.

6. Protein Synthesis of virus components

The organ cell’s internal ribosomal machinery (a bio-mechanism used to produce components of a cell for cellular regeneration & reproduction) is then utilised for protein synthesis to build all the proteins (components) to assemble the new virus.

This process is called translation. The mRNA is translated by the ribosomes and two types of proteins called the structural and non-structural proteins are synthesised and then assembled. The capsid protein coat and S-strands are synthesised at this stage.

7. Virion Assembly

Once the protein components of the virus and the RNA strands are built, the process of assembly of these components is done to form a new virus particle.

8. Release

After the virion assembly, the fully matured viruses are prepared to leave the cells to mark the end of the process of replication.

These newly manufactured viruses leave the cell abruptly or by the process of budding away from the cell surface membrane. In this abrupt process the virus destroys the cellular structure which causes cellular breakdown and thereby organ malfunction and eventually organ failure.

How COVID-19 damages the lungs and causes respiratory diseases?

Now that you learn the general process of how a virus enters, reproduces and then damages an organ, here is now the process of how the novel coronavirus COVID-19 reproduces and damages the organs in the respiratory system.

  1. The virus enters the body via the respiratory route. The droplets containing virus particles lodge in the nasal mucosa.

    If the immunity is strong, the virus is destroyed and eliminated within this first layer of immunity. If the immunity is weak, the virus penetrates through the mucous membrane and enters into contact with the target organ cell.

  2. The virus attaches to the lung cells (it attaches to the wall of the type II pneumocytes by its spike proteins called the S-spike to the receptor called the ACE-2).

  3. The next immunity barrier is activated and viral entry and replication is impeded.

    At this stage mild symptoms are experienced as a results of immune response. If the immune system is strong enough and adapts quickly to overcome the virus, symptoms subside after a few days. If the immunity is not strong enough then this proceeds to the next stage.

  4. The virus replication starts within the lung cells and lungs cells start to be damaged. The immune response is overwhelmed and as a results more severe symptoms like fever, tiredness etc. are experienced.

  5. The virus wins over the localized immune response and starts spreading into the rest of the body. Symptoms like fever gradually increase to a high grade and symptoms worsen.

  6. Spread of the virus is more prevalent in the alveoli of the lungs where the virus gains entry via respiratory route. Shortness of breath starts at this time.

  7. With the infection of alveoli, an intense immune reaction ensues (called a cytokine storm), leading to Acute Respiratory Distress Syndrome (ARDS). The immune system recruits an army of immune cells to fight with the infection, resulting in collateral damage to pneumocytes (lung cells), thrombosis of blood vessels and the damage of the lung tissues, eventually leading to poor oxygenation to lungs and suffocation.

  8. The fluid starts to accumulate in the lungs due to edema induced by chemical substances released by immune cells resulting in a severe shortness of breath which then requires ventilatory support.

  9. If adequate treatment is not administered, it could lead to death. 

Immune system: the only real guard against COVID-19

A healthy immune system can eliminate the virus at any step of the chain of infection whereas a weaker one fails to do so. The body tries to generate an intense immune reaction in order to fight with the infection and thus only a robust immune system can do that.

The virus is seen to also spread into other organs (not just the lungs) and produce organ damage but there are no casualties reported so far in such scenarios.

What can we offer you in Heal Within™

Heal Within™ is primarily a chronic disease treatment & prevention centre, based on an Integrated & Holistic treatment protocol. Our focus and relentless pursuit is to help chronic disease patients achieve these Three Primary Objectives.

  • Objective 1: Holistic Healing
  • Objective 2: Optimal Immunity & Disease-Occurence/Recurrence Prevention
  • Objective 3: Long-term Wellbeing

To learn the details of the what & why of these end-objectives, and understand why it is crucial that you establish this in your mind first prior to starting any healthcare treatment or prevention program, please go to Lesson 1 – First, Establish Your End-Objectives (if you not already done so).

We use an advanced Integrated & Holistic Treatment approach, by which we diagnose the root causes to the patient’s diseases by specialised tests in all 10 Pillars of Health, and then treat those specific root causes by specialised therapies that induce holistic healing and not just suppress symptoms as done in main-stream medical treatments.

By this protocol, we have consistently helped numerous patients with all forms of diseases (right from Cancer, Heart disease, Stroke, Kidney disease, etc. to High blood pressure, diabetes, skin diseases, auto-immune diseases, infertility & other women issues, obesity etc.;) achieve these Three Primary Objectives.

If you have any chronic disease and not getting the desired positive results from your present treatment, or if you want to optimise your health to prevent occurrences of any chronic disease, or if you want to optimise your immunity for optimal prevention against COVID-19, then just send us an enquiry or come visit our centre and see how we can help you achieve the Three Primary Objectives.

We have both: a comprehensive service in-clinic program, and a DIY-at-home program (i.e. do it yourself at home program).

Our offerings:

  • Education: How to Prevent & Treat of Chronic Diseases (including COVID-19)
  • Diagnosis: Comprehensive health screening for Diseases & their Root Causes (including COVID-19)
  • Prevention: Chronic Disease Prevention Programs (including COVID-19)
  • Treatment: Chronic Disease Treatment Programs
  • Rehabilitation: Post-treatment Rehabilitation & Optimisation Programs (including COVID-19)

Got Questions?

Click the chat button in the bottom right corner and send all your questions via the inquiry form. A rep will then reply at the earliest possible.

Lesson Author

Dr Lee Cheng Lok

Medical Director, Heal Within™

Dr Lee Cheng Lok is the founder & medical director in Heal Within™. This lesson series is a part of his mission to educate & heal patients with chronic diseases, and prevent others from experiencing chronic disease by using an Integrated & Holistic approach.


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