COVID-19

Basic Terms

Coronavirus: A general term for a virus family that can cause infections in both humans and animals. These viruses can lead to various diseases, such as SARS, MERS, and various forms of the common cold.

SARS-CoV-2: This coronavirus, identified in 2019, is the causative agent of the disease COVID-19. The name is an abbreviation for "Severe Acute Respiratory Syndrome Coronavirus 2."

COVID-19: The illness caused by an infection with SARS-CoV-2 is not necessarily present in every infected individual. It is only referred to as COVID-19 when symptoms occur. The acronym stands for "Coronavirus Disease" and the year of the first documented cases, 2019.

Symptoms of COVID-19

At the beginning of the COVID-19 pandemic, the most commonly reported symptoms were fever, dry cough, and fatigue. These symptoms were often similar to other respiratory illnesses, making it challenging to identify COVID-19 cases. As time passed, further research and the emergence of new virus variants led to the identification of additional symptoms, expanding the list of COVID-19 symptoms. These additional symptoms include loss of taste and smell, sore throat, headaches, muscle aches, and shortness of breath.

When patients continue to experience symptoms even after apparent recovery from COVID-19, it is referred to as Long Covid. Approximately one-third of individuals with initially mild symptoms and a higher proportion of those with severe symptoms may develop Long Covid. In some cases, these symptoms can persist for months.

The most common persistent symptoms of Long Covid include fatigue, headaches, joint pain, as well as impairments in taste and smell. Some studies also suggest that Long Covid patients may experience significant health issues such as strokes or diabetes mellitus.

Incubation Period

The incubation period refers to the time from infection to the appearance of the first symptoms. For COVID-19, this period typically ranges from 1 to 14 days, with symptoms often appearing around 5 to 6 days after infection. Even during this asymptomatic phase, the virus can be transmitted to other individuals.

How Does the Virus Spread?

The main route of virus transmission is through respiratory droplets that are released into the environment when an infected person coughs or sneezes. Other individuals can become infected if these droplets come into contact with their mucous membranes in the nose, mouth, or eyes.

While the original form of SARS-CoV-2 was already highly contagious, later variants have demonstrated even higher transmissibility. For instance, the viral load of the Delta variant is estimated to be approximately 1,000 times higher than that of the original version.

How Long Does the Virus Last?

• In the air: up to 3 hours

• On copper: up to 4 hours

• On cardboard: up to 24 hours

• On plastic and stainless steel: between 2 and 3 days

• Under special conditions such as an ideal temperature of 20 degrees Celsius (68 degrees Fahrenheit) and absence of daylight, the virus can survive on surfaces like glass, vinyl, stainless steel, as well as paper and polymer banknotes for up to 28 days.

SARS-CoV-2 Variants

During the replication of the coronavirus, errors can occur in the transmission of genetic information to the host cell. Such deviations are known as mutations. The resulting altered virus is referred to as a mutant or virus variant. While many mutations are neutral or have minimal impact, the rapid global spread and high infection rate have also given rise to some problematic variants.

These variants can be characterized by increased viral loads, which enhance their transmissibility and infectivity. While some mutations may make the virus less virulent, there are also rare cases where the changes make the virus more dangerous or even more deadly.

The variants are categorized according to the following scheme:

• VOI (Variants of Interest): A variant of interest currently being studied for its potential relevance.

• VUM (Variants under Monitoring): A monitored variant being observed for potential health implications.

• VOC (Variants of Concern): A concerning variant that requires special attention due to its properties.

This Is How We Protect Ourselves from COVID-19

1.Vaccination:
Vaccination has become a cornerstone in the fight against COVID-19. It stimulates your immune system to recognize and combat the virus more efficiently should you get infected. 

• Types of Vaccines: For vaccination, several options are available, such as mRNA vaccines like Pfizer-BioNTech and Moderna, as well as viral vector vaccines like AstraZeneca and Johnson & Johnson.

• Efficacy: While no vaccine offers 100% protection, the approved COVID-19 vaccines have shown high efficacy in preventing severe illness, hospitalization, and death.

• Booster Shots: With variants of concern emerging, booster shots are recommended for certain populations to maintain high levels of immunity.

• Common Side Effects: Typical side effects are mild and can include sore arm, fatigue, and mild fever. These usually subside within a couple of days.

• Schedule: The number of required vaccine doses has changed throughout the pandemic, depending on the situation and the specific type of vaccine. For most vaccines, initially, two doses were required at a specific interval, possibly followed by a booster shot.

• Eligibility: The vaccination requirements and eligibility criteria vary from country to country. Therefore, consult your family doctor for personalized information and recommendations.
  
  

2.Social Distancing:
One of the most effective ways to control the spread of the virus is to maintain a safety distance of at least two meters from people who do not live in the same household. Especially during lockdown periods with strict stay-at-home orders, a rapid decrease in daily reported new infections can often be observed.

3.Face Masks:
For the highest possible protection against infectious aerosols, it is advisable to use an FFP2 mask without an exhalation valve. Cotton masks, while reusable and practical, offer limited protection compared to FFP2 masks.

If you want to buy an FFP2 mask, you should look for the following criteria:

• The CE mark should be visible.

• Marking according to EN standards should be indicated.

• A four-digit identification number of the certifying testing institute should be present.

• For effective protection, it is important that the mask fits correctly.
  
  

4.Hand Hygiene:
Thoroughly washing your hands with soap for at least 20 seconds is effective in inactivating SARS-CoV-2. If you have the opportunity to wash your hands, additional disinfection is not necessary and could even be counterproductive as it can unnecessarily strain the skin. Hand sanitizers should be used primarily when handwashing is not possible. In such cases, the duration of disinfection should be at least 30 seconds.

Coronavirus Testing

PCR Test:

• Purpose of the Test: Detection of SARS-CoV-2 genetic material

• Procedure: Swabs are taken from the mouth, nose, or throat

• Time Frame for Results: Approximately 1–2 days

• Reliability: Very high, although human errors, such as inadequate sample collection or improper storage, can distort results. It is considered the most accurate among various COVID-19 tests.
  
  

Rapid Antigen Test:

• Purpose of the Test: Detection of SARS-CoV-2 proteins

• Procedure: Swabs are taken from the mouth, nose, or throat

• Time Frame for Results: Approximately 15 minutes

• Reliability: Lower sensitivity compared to the PCR test. A positive result requires confirmation by a PCR test.
  
  

Antibody Test:

• Purpose of the Test: Detection of antibodies against COVID-19 (as an indicator of a past infection)

• Timing for Use: Useful around 3–4 weeks after suspected or confirmed infection

• Procedure: Blood sample

• Time Frame for Results: Approximately 1–2 days

• Reliability: Tests with high sensitivity and specificity are preferred.

Goals in the Pandemic

Flattening the Curve as the First Measure:
The "Flattening the Curve" strategy aims to slow down the steep increase in COVID-19 infections and thus prevent the healthcare system from becoming overwhelmed. By flattening the infection curve, it ensures that the number of people infected at the same time reaches a level that does not exceed the capacity of healthcare facilities. Initial measures for this include restrictions on public life, maintaining a safe distance from other people, and strict adherence to hygiene rules. These strategies are designed to minimize the risk of rapid virus spread, thereby reducing the number of severe cases and deaths.

Maintaining a Flat Curve as an Ongoing Strategy:
After successfully flattening the infection curve, the next challenge is to maintain this state in the long term. The primary goal remains unchanged: to avoid overwhelming the healthcare system. To ensure a sustained low infection rate, continued rigorous protective measures are necessary.

Searching for a Cure as the Ultimate Goal:
The ultimate goal in combating the COVID-19 pandemic is, of course, the development of a reliable treatment or an effective vaccine. Numerous research groups worldwide are working intensively on various therapeutic approaches and vaccine candidates. Until such a remedy is widely available, maintaining a flattened infection curve is important to prevent overwhelming the healthcare system.

In December 2020, approximately a year after the COVID-19 outbreak, several vaccines were approved in Europe. These vaccines have shown high efficacy in preventing severe cases of COVID-19 in studies. Given new virus variants that could potentially affect the efficiency of the original vaccines, they are continually adjusted to remain effective against the currently circulating variants. This ensures that vaccine protection stays up to date with the latest research.

Additional Details on the SARS-CoV-2 Virus and Its Lifecycle

Characteristics of SARS-CoV-2

• Genetic Structure: SARS-CoV-2 is an RNA virus, meaning its genetic information is stored in a single-stranded RNA molecule that is positively charged.

• Size and Visibility: With a diameter of 60-140 nanometers, the virus is too small to be seen with a light microscope. An electron microscope is required to make it visible.

• Metabolism: Unlike bacteria, viruses do not have their own metabolism. They cannot generate energy or produce proteins independently. They are not considered living organisms in the classical sense but rather rely on the biological systems of their host cells.

• Parasitic Nature: The virus depends on the protein synthesis machinery of the host cell to replicate itself. It is referred to as an "obligate intracellular parasite," meaning it requires a host cell to replicate.
  
  

The Replication Cycle of SARS-CoV-2

1. Adsorption: The virus attaches to a specific site on the host cell, the ACE2 receptor, using its spike proteins.

2. Activation: Fusion with the cell membrane activates the virus's spike protein.

3. Penetration: The virus enters the cell.

4. Uncoating: Its RNA is released from the protective envelope and delivered into the cell.

5. Translation and Replication: The RNA is then used for the production of proteins and for replicating the virus's genetic material. The cell often doesn't even recognize it as foreign RNA.

6. Self-Assembly: New viruses are assembled in the endoplasmic reticulum, a cell organelle.

7. Release: These new viruses are encapsulated and released from the cell.
   
   

Contagion and Infection Dynamics

• Number of Required Virus Particles: Approximately 1000 virus particles are needed to infect someone.

• Release through Coughing and Sneezing: An infected person can release up to 200 million virus particles into the environment through coughing or sneezing alone.

Misinformation During the Pandemic

As the pandemic progressed, the spread of conspiracy theories and misinformation also increased. One of the significant problems was the so-called "prevention paradox." This means that when precautionary measures work well, many people see no reason for their existence. They don't notice the prevented harm but only perceive the current restrictions as burdensome.

The invisibility of success opens the door to conspiracy theories. Because many people fear losing control, they turn to such theories to regain a sense of power. Unfortunately, this leads to scientifically based pandemic control measures being discredited.

A look at international data shows that hesitation costs lives and strains healthcare systems. This should remind us of the value of our precautionary measures, even if they appear invisible.

COVID-19 Continuing Education Courses

During the pandemic, a variety of continuing education courses were offered to deepen the understanding of COVID-19. To expand and keep my knowledge up to date, I also participated in some of these courses.

Closing Words

In times of a pandemic, it is even more important that we rely on reliable scientific information. When seeking answers to complex questions, we should turn to experts in the respective field and stay informed about the current scientific consensus. Some information that was considered certain at the beginning of the pandemic has been revised through new studies. That's how science works. We should always remain open to new knowledge and adjust our behavior accordingly to protect ourselves and our fellow human beings.

Update Status:
Originally created post: 01/2020
Last updated: 02/2025