COVID Crash Course: Part 2 - Testing, Immunity and Vaccines

Jonathan Jenkins

Coronavirus Testing

You have probably heard this statement often: "We have to test more!” and there’s a good reason for that. Tests are important in the corona crisis for a number of reasons. They help those affected get help in time while also preventing them from infecting others. And they provide politicians and researchers with the information they need to make important decisions on how to deal with the pandemic.

There are various methods to determine whether you currently have COVID-19 or whether you might have had it at some point in the past. The most relevant methods are:

  1. The PCR test, which detects the virus’s genetic material.
  2. The antibody test, which detects immune response cells that fight the virus after an infection.

Antibody Tests: Have I Already Had the Disease?

During an attack by an infectious disease like COVID-19, the immune system usually forms antibodies to fight the pathogens in the body. There are different antibodies for each pathogen. Laboratories can therefore specifically detect the antibodies in the blood that can be attributed to the SARS-CoV-2 virus.

The antibodies are produced during the course of the disease and can be detected about one to two weeks after infection. That’s why the tests are not well suited for detecting an acute infection [19].

What is the Benefit of Antibody Tests?

Since the antibodies remain in the body even after the infection has been overcome, an antibody test can help you determine whether you’ve had the coronavirus. This is important because many patients do not show clear symptoms - COVID-19 often hides behind mild cold symptoms or it even runs its course without any symptoms.

If you have survived the disease and antibodies are present in your blood then you probably cannot infect others. People who are immune may be released from contact prohibitions in the future and could go back to work, for example. The health authorities hope to use doctors and nurses who are immune in a targeted manner to treat COVID-19 patients [20].

Antibody tests are also a means for scientists to obtain data on the trajectory of the pandemic. Many researchers have been conducting large studies with antibody tests since May 2020 to find out how widespread the coronavirus is in the population [19].

With the ceracreen® coronavirus antibody test, you can take a blood sample at home and send it to a specialist medical laboratory, which will test your sample for antibodies against SARS-CoV-2. The test measures the specific IgG antibodies with the established ELISA test procedure. These antibodies remain in the body the longest and provide the most meaningful results in the analysis.

PCR Tests: Am I Sick Right Now?

The common method to detect an acute infection with COVID-19 is the so-called PCR test. PCR stands for polymerase chain reaction. This is a method that enables laboratories to detect the virus’s genetic material in a DNA sample.
The cerascreen® Coronavirus Test uses swabs from various locations in the body. The most common source is the throat: The virus is mainly present in the throat in the first week of the disease - the time period when most of those affected show the first symptoms. Later, the viruses are often found in the lungs. Doctors in hospitals can also take swabs from the lungs to detect the virus there [17,18].

The cerascreen® Coronavirus Test is a PCR test with throat swab that meets the legal requirements for medical devices and which you can perform easily at home. You carry out the test in the safety of your own home. Your sample is then collected by your mail carrier and taken to a specialist diagnostic laboratory. The test is useful if you want to determine whether symptoms such as coughing and fever are COVID-19 or simply the flu or a cold. We are committed to reducing the burden on medical personnel by making more testing possible.

Why is it Important To Reduce My Contact With People?

The most important measure to contain the coronavirus pandemic is reducing direct contact among individuals as much as possible - in other words "social distancing."

The simple principle behind it is that the fewer people who come into direct contact with each other, the fewer infections can occur. This is particularly true because many people carry the virus inside them and are already contagious before they manifest symptoms.

What have social distancing measures achieved so far? This is the question that researchers at Imperial College in London have been asking. In their study, which they published at the beginning of June 2020, they concluded that measures such as contact restrictions and lockdowns played a major role in reducing the number of infections [21].

What Does "Flatten the Curve" Mean?

The term "Flatten the Curve" refers to a graphical representation of how many people are infected over a period of time: if the infections are spread over a long period of time, the result is a long, flat curve of cases. If there are many cases at once, the curve becomes very steep and exponential growth occurs.

Did you know? When something grows exponentially, it multiplies by the same factor within a certain period of time. Let’s take the example of cases of illness doubling every day: If two people are ill and each of these people infects two more in one day, 8 people are infected after 2 days, 256 after 7 days, 32,768 after 14 days and more than 4 million after 21 days.

The problem with a steep curve is that a large number of people falling ill at once means that many of them have to simultaneously be treated in intensive care units. This could overstretch the capacities of the healthcare system - the beds in the hospitals, the available medical and nursing staff, the drugs and respiratory equipment could all be insufficient in light of the task. As a result, doctors may have to decide which patients to treat and which to neglect, resulting in more deaths.

So the goal is to spread the infections over a long period of time. This is the only way to ensure that all people with severe cases receive the best possible medical treatment.

What Does It Mean to “Shelter in Place”?

Domestic quarantine is generally ordered for you by your health authority if you have tested positive for the SARS-Cov-2 virus or have strongly suspicious symptoms and have had contact with people infected by the virus. Quarantine means that you are not allowed to leave your home at all, not even to go shopping, to go to work or for walks. This usually applies for 14 days. A negative corona test, usually a PCR test, can shorten the quarantine in many cases.

Note: In many places, it is a criminal offense to ignore the prescribed quarantine! A violation can result in fines and even imprisonment [23]. You can have your neighbors, family or friends do the shopping for you, for example, and leave them at your door.

What Protective Measures Are in Place?

There are various recommendations that help to contain the spread of the coronavirus pandemic. Most recently, it has been shown that the compulsory use of masks introduced in many countries may have contributed to slowing down the spread of COVID-19.

The World Health Organization (WHO) recommends the following measures to protect oneself and others [25]:

  • Hand hygiene - wash your hands regularly and thoroughly (for at least 20 seconds) with soap and water, or disinfectant.
  • Always sneeze and cough in the crook of your arm and discard used tissues immediately.
  • Avoid touching your face, especially your nose, mouth, and eyes.
  • Stay at home if you experience signs of a cold, call a doctor if you have a cough or fever.
  • Keep at least six feet from other people and avoid crowds.

Recent findings on the transmission of SARS-CoV-2 via aerosols in the air also suggest that regular ventilation may be important to prevent the virus from spreading indoors.

If someone in your household is ill, you should also reduce your exposure to the public to avoid infecting others. In this case, be sure to regularly clean surfaces with soap and water, and to disinfect them afterwards. This applies especially to things we touch frequently in everyday life, such as door handles, light switches, toilets, sinks, tables, keyboards, and telephones [5].

What is the Benefit of Mask Protection?

Among the recommendations by governments and experts is the recommendation to wear a mask. This refers to simple masks, which are usually made of cotton. They are mandatory in many states. 

The main benefit of these everyday masks is that when infected people wear masks, the risk of infecting others is reduced. Masks lead to individuals emitting less of the viruses via coughing, sneezing, and speaking. This has been investigated in a study by the journal Nature [8].

Don't Underestimate The Power of Masks 

In the course of the summer, there was increasing indication that masks not only protect others, but also the wearers. American researchers found that wearing a mask leads to smaller amounts of the virus entering your body when you come into contact with an infected person. This could lead to a mild case with weak or no symptoms [38].

At the end of May 2020, a Chinese study suggested that the importance of masks has long been underestimated. According to the authors, countries that introduced compulsory masks were more effective than others in taming the coronavirus [26]. This and other studies show that masks can prevent people with the disease who do not yet have symptoms from spreading it [27].

Be sure to wear the mask correctly:

  • The masks should cover your mouth AND nose.
  • Simple masks made from cotton can be used as they can also reduce the risk of transmission to other people.
  • You should not wear a single mask for too long. It is best to change the mask when it has become damp. Many of the masks made from cloth can then be washed and used again.

Strengthening Your Immune System

With an infectious disease such as COVID-19, the immune system is constantly fighting off the pathogens in the body, in this case the SARS-CoV-2 virus.
People who have an immunodeficiency are therefore considered to be at high risk of contracting COVID-19 because their immune system will have difficulty coping with the virus, possibly resulting in severe and dangerous symptoms [1].

A healthy immune system does not protect you from being infected by the coronavirus. This is because the human immune system is not yet adapted to the new virus. We all need to first build up antibodies against the pathogen before our bodies can fight it off effectively [1].

There is still no clear scientific evidence as to whether it is possible to strengthen the immune system with food supplements and thus mitigate the course of COVID-19. However, it can be useful to identify and compensate for any nutrient deficiencies so that your body is optimally prepared for an infection. Important nutrients for the immune system include vitamin D and the minerals zinc and selenium.

Vitamin D and COVID-19

Though we are still waiting for conclusive evidence, some studies now indicate that a sufficient supply of vitamin D could influence the course of COVID-19. 
This is what the German nutritional scientist Hans Konrad Biesalski argued in a publication from June 2020: Humans with a Vitamin D deficiency more frequently have illnesses such as high blood pressure, cardiovascular diseases and diabetes. These pre-existing conditions are known to increase the risk of severe cases of the disease, which would possibly be aggravated by a vitamin D deficiency. Biesalski therefore recommends testing people with COVID-19 for their vitamin D levels [39].

A study from Spain published in October 2020 found that 82 per cent of the patients who were hospitalized in Spain because of COVID 19 had a vitamin D deficiency. The authors of the study recommend that the vitamin D status of people with severe COVID-19 be checked and any deficiency compensated [for 43].

In addition, comparisons among European countries had shown that where the vitamin D supply was lower, the COVID-19 mortality rate was higher. For example, people in Italy and Spain had a higher risk of dying than those in Scandinavia, where the vitamin D supply is generally better [40, 41].

A number of studies are still ongoing to investigate the relationship between vitamin D intake and COVID-19. What we already know for sure is that vitamin D plays a role in our immune defenses and in the regulation of blood pressure. In addition, it may help to prevent inflammation in the lungs, which can cause serious complications in COVID-19 [39].

Can Vitamin D Protect Me from the Coronavirus?

The above-mentioned research results do not mean that taking vitamin D will protect you against the coronavirus.

For one thing, a healthy vitamin D level does not prevent infection. It only possibly influences the severity of the disease. On the other hand, according to current knowledge, vitamin D supplements have a positive effect especially if you suffer from a deficiency. The people considered in the studies were also usually elderly people in nursing homes who often suffer from severe vitamin D deficiencies. To what extent the results can be transferred to a healthy, younger population, still remains to be seen.

You can examine your personal vitamin D supply with a blood test, for example with the cerascreen® Vitamin D Test.

Vaccines Against COVID-19

In medicine, vaccinations are the Holy Grail of therapies against infectious diseases. After all, a vaccine allows us to treat a disease before it develops. A comprehensive vaccination also ensures that a pathogen, such as a virus, won’t spread. In the past, various pathogens have been almost or completely eradicated, such as polio, smallpox and whooping cough [30].

Why Are Vaccines Against COVID-19 Important?

When it comes to the SARS-CoV-2 virus and the COVID-19 disease, the search for a vaccine is a race against time. Without vaccinations, we would have to reckon with one of two scenarios: Either we would live for years with drastic restrictions in our daily lives or the virus would spread rapidly, which could lead to a high number of deaths.

Did you know: Vaccinations stimulate your immune system to build up a defense against a specific pathogen, for example by producing antibodies? Vaccines contain either live but attenuated pathogens (live vaccine) or dead pathogens cells (dead vaccine). Successful vaccinations reduce the risk of people becoming infected with a disease and spreading it further [29,30].

Currently there are 2 authorized and recommended vaccines for use against COVID-19 and as of January 11th, 151,000 people in the US have been fully vaccinated.

As Vaccine supplies are limited, it's still important to observe the social distancing, masks, and general sanitation practices that have been recommended for the duration of the pandemic.

Also, did you know: Vaccines can be distinguished according to whether living or dead cells of the viruses are used to produce them? Inactivated vaccines (ones using dead parts of the virus) are easier and faster to produce in large quantities. However, they are also considered to be more risky, which is why research into vaccinations against COVID-19 in the US and Germany is currently focusing more on live vaccines [31].

COVID-19 Therapeutics

The right drugs could help people with severe cases of COVID-19. But there are unfortunately still few approved procedures.

The most recent data from the as yet unpublished RECOVERY study by Oxford University in the UK caused a sensation in mid-June 2020. The researchers examined the drug dexamethasone, which was originally developed for the treatment of asthma. Dexamethasone inhibits inflammation and was shown in the RECOVERY study to reduce mortality from severe cases of COVID-19 by one third [34]

It is still too early to call it a breakthrough though: The data must be further evaluated for the final results of the study. If the hopes of the Oxford researchers are fulfilled, however, dexamethasone could be a cheap and effective treatment for severe COVID-19 cases.

Scientists are working on other types of compounds that may be suitable for the treatment of coronavirus [35]:

  • Antiviral drugs. They slow down or prevent the reproduction of viruses in the body. Some also stimulate the immune system so that the body can fight the pathogens better.
  • Drugs for lung diseases. They counteract restrictions that can result from severe pneumonia. For example, they ensure that the lungs continue to supply the blood with sufficient oxygen.
  • Immunomodulators: In some cases, the immune system overreacts and can cause damage to the lungs, for example. These agents can prevent such an overreaction.

Which Drugs are Currently Being Tested?

Some of the drugs that scientists are investigating have already made the headlines. These include [36]:

  • Remdesivir. This drug was developed for use against Ebola. It could fight the coronavirus in the body. In some initial tests, it seemed promising. Now there are larger studies in Asia, the US, and Germany.
  • Chloroquine. The malaria drug initially aroused great hopes. However, the studies have been inconclusive - it is not yet possible to say whether Chloroquine could help against COVID-19 in the future.
  • Tocilizumab. The rheumatism drug could work against overreactions by the immune system in the lungs. An international study with 330 COVID-19 patients is currently underway.

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