The novel coronavirus causes a dangerous illness, and a vaccine is not in sight. We answer the essential questions about everything to do with the pandemic and clear up the myths and misinformation.
When coronavirus SARS-Cov-2 arrived March 2020 in Europe, it most likely turned your daily life upside down too. Contact restrictions and curfews have been put in place to prevent the virus from spreading too quickly and unleashing chaos on the healthcare system. Countless businesses and public establishments have been closed. Meanwhile many people are being treated in hospital for a life-threatening pneumonia caused by the virus. No effective vaccine or medication has been discovered to date, as scientists around the world rush to develop a vaccine. Additionally possible ways of testing large numbers of people are being trialed. In this article we summarize straightforward answers about the topic--from how the virus is spread and the symptoms, to tests and protective measures like safety guidelines, hand hygiene, and face coverings.
The latest information and official recommendations can be found additionally on the NHS website.
Where does the virus come from?
The first documented case of COVID-19 occured in the Chinese province of Wuhan in December 2019. How the first infection occured is still unclear. The current theory is that the virus originated in bats. It may possibly have found its way through other animals to humans. 
The virus SARS-CoV-2 was identified by researchers in lab tests in January 2020. Shortly afterwards, the infection rate in China skyrocketed and the illness became a pandemic, or worldwide epidemic. In Europe, the first cases occurred in northern Italy and presumably spread from there to Austria and Germany. According to reports, the holiday destination Ischgl in Austria was likely an epicentre for the virus–those who went there for a ski holiday are thought to have spread the virus throughout Europe. 
Good to know: What do the abbreviations stand for? SARS-Co-V-2 is the scientific name for the virus that causes the pandemic. SARS stands for Severe Acute Respiratory Syndrome. The illness caused by the virus is called COVID-19 (Coronavirus Disease 2019).
How does it spread?
The typical way in which COVID-19 is spread amongst people is through droplet contamination. Tiny mucus droplets can transmit the virus from person to person through coughing, sneezing, and speaking. The droplets containing the virus are relatively heavy, and sink after a short period of time to the ground, covering a distance of around 2 metres. This is why it is recommended to keep a safe distance of at least 1.5 metres in order to prevent contamination.
Time is also an issue, as the longer people are near each other the greater the risk of contamination. A rule of thumb from the USA: do not stay longer than six seconds near someone. , 
Am I contagious even if I don’t have symptoms?
Infected persons are in fact contagious before they develop any signs of illness. Many experts say this is one of the biggest factors for how COVID-19 has spread so quickly throughout the world.
According to an estimate from Chinese researchers, 44% of people who are sick were contaminated by people who did not yet show any symptoms. Other researchers found that in certain regions of China this percentage was between 48 and 62 percent. [2,3]
Can I get ill from contaminated surfaces?
It is possible that one can become ill from touching contaminated surfaces like door handles and other objects. In this case the virus is transferred from the surface onto a hand, which then can make its way into the mucous membranes when one touches their face. Although this is possible, it is rare in comparison to droplet contamination. [4,5]
Can the virus transmit through exhaled air?
It is still being researched just how far the virus can spread through exhaled air.
The aerated particles that we expel when we breathe are smaller and lighter than those we expel by coughing, sneezing, and talking and can stay suspended in the air longer, but are also easier for the wind to carry off. [6,7]
Am I immune, now that I have had the virus?
The reason that you really only get sick once during an outbreak of the cold is immunity. Our immune system produces specific antibodies, among other things, to fight the pathogens. If the pathogen later re enters the body, then the body’s defense recognises it and renders it harmless.
It is still too early to say for sure if this will be the case with the SARS-CoV-2 virus or not. According to the the World Health Organization (WHO), there is not sufficient scientific evidence as of yet. However many researchers are optimistic. Christian Drosten, Professor of Virology from the Berlin Charité, said in a Coronavirus-Update-Podcast on the German national radio station at the end of April that he reckons that after recovery from an illness a person is immune for two years, possibly even longer. 
Early research with monkeys and humans suggest that only in very rare exceptions can a person develop the illness a second time. Generally speaking a person is likely immune for a few months or up to three years once they have had COVID-19. 
Are there studies that give reason to doubt there is immunity?
The media has presented a few studies from South Korea and China in the past weeks, in which it was suggested that people who had recovered from coronavirus were shown to have been reinfected. The study authors suspect that the virus may be able to “reactivate,” which means however they were not infected a second time. Some experts believe this is due to the common testing procedure, PCR. The tests can only measure the virus in certain parts of the body and at certain times, which can mean the test is negative even though the virus is present. [8,9]
What are the symptoms?
The symptoms of COVID-19 vary from person to person. There are the asymptomatic infections (where the person has no symptoms), the light cold-like symptoms, and the severe illness with life-threatening pneumonia.
Symptoms for mild or moderate cases
There are are studies about the symptoms from China, where the virus first occured. According to research, around 80 percent of cases are mild or moderate. Studies from other countries suggest that this number is actually much higher.10] People with mild illness sometimes had no symptoms, or mild symptoms like a dry cough, fever, stuffy nose, or mild pneumonia. New reports show that the loss of taste and smell may be the typical sign of an infection.
The World Health Organization has also reported the following less common symptoms:
- headache, aches and pains
- a rash on skin
Symptoms of a severe illness
A difficult illness with COVID-19 causes a severe case of pneumonia. This manifests with difficulty breathing and respiratory distress; in very severe cases it can lead to lung failure and spread to other organs. The very severe illness cases can be fatal. These patients need intensive care in hospital and often require respirators. Researchers warn however, that these numbers are hard to confirm, as the number of unreported cases is very difficult to estimate.
What percent of corona infections result in severe illnesses differs by region. It varies between three and six percent of cases. [1,10]
Who is at higher risk from coronavirus?
When one hears talk about who is at higher risk from coronavirus, it is not about who can be infected with the virus. Anyone can be infected with the virus, as it has already appeared in people of all ages. Higher risk refers to the fact that some people have a higher risk of becoming severely ill. The NHS lists the following people as having a higher risk :
- people aged 70 and older
- people with pre-existing conditions, like heart disease, chronic lung conditions like COPD, chronic kidney disease, diabetes, cancer
- people with a weakened immune system, which may be caused by disease or taking medicine that affects the immune system (e.g. cortisone)
How can one test for corona?
You have probably heard it often enough: “we need to test more!” Testing during the corona crisis is important for many reasons. It can help those who are sick get help in time and not infect others. It also gives politicians and researchers the necessary information to make informed decisions about how to react to the pandemic.
There are different methods to find out if you currently have the COVID-19 illness or if you had it at an earlier point in time. The most relevant methods are a PCR test, which identifies the presence of the genetic material of the virus during an infection, and the antibody test, which tests for the immune system cells that fight the virus.
PCR Test: Do I have the illness now?
The approved method of identifying the COVID-19 illness is the PCR test. PCR stands for Polymerase Chain Reaction, a process in which labs can detect if the genetic material of the SARS-CoV-2 virus is present in a DNA sample. The sample swabs can be used on different areas. Commonly a throat swab is used, as in the first week when most are experiencing the first symptoms, the virus can be found here. The virus concentrates in the lungs as the illness progresses. In hospital, a medical professional can use a lung swab to test for the virus. [12,13]
The cerascreen® Coronavirus Test is a PCR test with throat swab, which meets the legal criteria for a medical product but is nevertheless easy to perform at home. You can take the swab in the safety of your home and the sample will be picked up by DHL Express and sent to a diagnostic lab. You then receive your test result in two to three days.
It is a good idea to take the test if you have symptoms such as coughing, fever, and sniffles and want to see if it is COVID-19 or a simple cold or flu. Cerascreen wants to help more people get tested and relieve medical professionals of this task.
Antibody Test: Was I already ill?
During an infection like COVID-19, the immune system produces antibodies to fight the pathogen. There is a different, specific antibody for each pathogen. A lab can then detect the specific SARS-CoV-2 virus antibodies in the blood.
Antibodies develop during an illness and are detectable as early as one to two weeks afterwards. This is why these tests are not suitable to detect an acute infection. 
What is the point of an antibody test?
As antibodies stay in the body after recovery from an infection, an antibody test can be used after the fact to determine if one had coronavirus. This is important because so many infected do not have clear symptoms, and so in this way COVID-19 hides behind mild cold symptoms or causes no symptoms whatsoever. When one has the antibodies and so therefore has had the virus, they are not likely not to become infected again and cannot transmit the virus to others. People who are immune may no longer have to follow the safety guidelines and return to work, for example. The health authorities hope to be able to strategically use doctors and nurses who are immune to care for infected patients. 
Researchers hope to use antibody tests to collect data about the course of the pandemic.
Antikörpertests sind auch eine Hoffnung der Wissenschaftler, um Daten über den Verlauf der Pandemie zu erhalten. Das Robert-Koch-Institut unter anderem plant, ab Mai 2020 große Studien mit Antikörpertests durchzuführen, um herauszufinden, wie verbreitet das Coronavirus in Deutschland schon war .
With the cerascreen® Antibody Test you can take a blood sample easily at home, which will then be analysed in a medical diagnostic lab for SARS-CoV-2 antibodies. The test uses the approved ELISA analysis method to detect specific IgG antibodies, which are the type of antibodies that live the longest and therefore provide the most diagnostically relevant measure.
Why is social distancing important?
The most important measure to slow the corona pandemic: avoid contact to other people as much as possible. “Social distancing” is based on the principle that the less people meet, the less the infection can be spread. This is especially true considering that many people are carriers of the virus without being aware of it.
In addition to social distancing, the UK government has implemented restrictions against meetings and gatherings, the closing of bars and restaurants, as well as cancelling public events. Some of these restrictions were lifted or lightened on Wednesday 13 May. See the UK government website for more information.
When may I leave my home?
In the UK you are still allowed to leave your home to buy essentials like food and medicine, as well as to go to work where you cannot work from home. You may of course also go outside for any medical needs. It is now also permitted to go outside to get fresh air and to exercise. You can do this in the company of people that you live with, or one person who is not part of your household. If you go jogging in the park, take the dog for a walk, or stroll around the block, the risk of infection is relatively small. Studies also show this is extremely important for the psyche and it does your body good to get outside. 
Good to know: “physical distancing” would be the more correct term. Naturally one is still allowed to keep contact by telephone or internet. Use the opportunity to have video calls with friends and family – this sort of digital contact feels the most like meeting for real.
What does “flattening the curve” mean?
„Flattening the curve“ refers to the representation of the number of infections over time in a graph. The more spread out the infections are over the period of time, the longer and flatter the curve is. If there are a lot of new cases in a short period of time, the curve will become very steep.
The problem with a steep curve: If many people become ill all at once, then the number of people with severe illness requiring intensive hospital care could overwhelm the capacity of the health system. The beds in hospitals, the number of medical personnel and nurses, medication, and respirators could all be insufficient and force doctors to decide which patients receive treatment and which will not, which would lead to more deaths. The goal is therefore to distribute the rate of infection over a longer period of time, so that all people with a severe illness can receive the best medical care.
What does self-isolation mean?
Self-isolation requires a person or household with a person showing symptoms of coronavirus to stay home. This means you may not go outside, even to buy food. The isolation period lasts for 7 days starting with the first day of symptoms. All other household members who do not become ill must isolate for 14 days. Should another person in the household begin to show symptoms, they will need to stay in for 7 days starting from the first day of their symptoms. Try to order your shopping online, and ask friends or relatives for help walking the dog, buying groceries, or getting medicine .
If the social isolation is difficult for you, reach out to friends and family for support.
What are the protective measures in place?
There are different recommendations to help hinder the spread of the corona pandemic. The World Health Organization recommends the following steps to protect yourself and others: 
- Hand hygiene – wash your hands often and for at least 20 seconds with soap and water, or use hand sanitiser gel.
- Always cough or sneeze into your elbow and dispose of tissues immediately.
- Do not touch your face, especially not your nose, mouth, or eyes.
- At the sign of a cold, stay home. If you have a fever or cough, contact the NHS 111 online.
- Keep at least a metre distance to other people and avoid groups.
If someone in your household is ill, you should try to keep your distance to reduce your risk of becoming infected. Clean common surfaces regularly with soap and water and disinfect your hands afterwards. This includes things like door handles, light switches, toilets, sinks, tables, keyboards, and telephones.
What do masks and face coverings do?
If you go outside with a face covering, you are not guaranteed protection from getting the virus. Only special medical protective masks, which are used by doctors and nurses, offer this protection. The main reason for wearing a mask is simply to reduce the risk of infecting others. If your face is covered, then you cannot transmit the virus as easily when you speak, cough, or sneeze, as less particles are released into the air. This was covered in a study in Nature magazine. 
This is why it is recommended for people to wear face coverings in enclosed public areas, especially where social distancing cannot be maintained, such as shopping and public transportation. In this way if someone is infected but does not show symptoms, they are less likely to transmit the virus .
Face coverings should cover the nose and mouth. Even simple and homemade face coverings can be helpful in reducing the rate of transmission.
Apps und Tracking Data
Some experts see a glimmer of hope with apps and mobile data. Certain apps can be used to track movement and contact. This would allow authorities to select people for testing and isolation. Virologist Christian Drosten expressed the hope that authorities could use the data from these apps to replicate an “infection network,” thereby allowing for an automated notification process for isolation measures. This could allow the rest of the population to return to normal life. But it would only work if enough people participate. According to Drosten, at least half of the population would need to use these apps. Those with fitness trackers could “donate” their tracking data. However, not everyone would be willing to cooperate, and it must be assured that only the research institute would have access to these data. 
Support the immune system
In the case of an infectious disease like COVID-19, the immune system is constantly fighting pathogens, in this case the SARS-CoV-2 virus. People who are immunocompromised due to medical conditions are therefore at a higher risk of becoming severely ill from COVID-19. Their immune system cannot fight off the virus as well and they may therefore develop acute and dangerous symptoms. 
A healthy immune system cannot prevent you from contracting the virus. This is because our immune systems are not prepared for this novel virus. In order to neutralise the virus, the immune system must first produce the right antibodies.
There is no scientific data that show if it is possible to strengthen the immune system with supplements to ensure a milder case of COVID-19. However, it can be helpful to identify a possible nutritional deficiency and correct it, so that your body is prepared to fight the virus. Vitamin D, zinc, and selenium are some of the important vitamins and minerals the immune system needs.
Vaccine for COVID-19
In medicine, vaccines are considered the most effective method to treat infectious diseases. A vaccine basically treats a disease before one even contracts it. A comprehensive vaccine also ensures that a pathogen like a virus cannot spread. This is how diseases have been eradicated in the past, like polio, smallpox, and pertussis (whooping cough). 
What is the importance of a COVID-19 vaccine?
The search for a vaccine against the SARS-CoV-2 virus and the subsequent COVID-19 illness is a race against time. If a vaccine is not found, then we have two possibilities to contend with. Either we must live for years with drastic alterations to our daily lives, or the virus spreads further, which could lead to a high number of deaths.
Good to know: How do vaccines work? Vaccines stimulate the immune system to develop a defense to a specific pathogen, usually by producing antibodies. Vaccines contain either live or weakened pathogens (attenuated vaccine) or dead pathogen cells (inactivated vaccine). Successful vaccinations reduce the risk that people will become infected with an illness and pass it on. 
When will there be a COVID-19 vaccine?
How long does it take to develop a vaccine? It can sometimes take years to develop a vaccine. And although researchers all over the world are under pressure to work on this, the development will take at least 12 to 18 months. An approved vaccine is not expected to be ready before the beginning of 2021. This is because a vaccine must be thoroughly tested, just as with other medicines. However, as vaccines contain pathogens or parts of it, scientists must make certain that the vaccine is safe. Otherwise millions of people could end up with unforeseen effects. 
What are scientists working on now?
According to an overview study, scientists all over the world are working on around 100 different types of vaccines for coronavirus.  However only some of these are as far as the clinical phase, where they are being tested on people. 
In China, researchers have developed a inactivated vaccine that showed promise in a study with rhesus monkeys. The animals were given the vaccine, then received a high dose of the virus injected into the lungs. Thanks to the vaccine, the monkeys had developed antibodies against the virus and could repress the virus. There was no case of a dangerous immune system overreaction– a side effect that can sometimes impede research with inactivated vaccines. 
These animal studies are only the first step, however. It has not yet been shown that these results can be repeated, or if the results hold for humans. Vaccines like this must first be tested in large clinical studies.
Good to know: Live vaccines and dead vaccines. Vaccines are differentiated by whether they contain live or dead cells of the virus. Inactivated vaccines are easier and faster to produce in large quantities. They carry a higher risk, however, which is why research for a COVID-19 vaccine in the USA and Europe is focused on using an attenuated vaccine.
Medication for COVID-19
The right medication could be especially helpful for people who become severely ill with COVID-19. There is not yet any approved medicine for COVID-19, as there are no studies and approval process. Scientists are working on different types of drugs which could be used to treat coronavirus: 
Which medicines are being tested?
Some medications which are currently being tested have made the headlines. This includes: 
Remdesivir. This medication was developed for Ebola and could fight the virus in the body. In some tests it shows promise. Currently it is being tested on a large scale in Asia, the USA, and Germany.
Chloroquin. This malaria medication has researchers very hopeful. Study results have not been unambiguous thus far, so it can not yet be determined if cholorquin could be used to fight COVID-19 in the future.
Tocilizumab. This rheumatic medication can fight overreactions of the immune system in the lungs. Results from a large international study with 330 COVID-19 patients are expected to be published this summer.
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