German virologists say people ‘initially immune’ after coronavirus infection

While a lot is still unknown about the novel coronavirus, German scientists are shedding light on why antibody tests will become increasingly important.

German virologists say people 'initially immune' after coronavirus infection
A healthcare worker holds a package of coronavirus tests in Saxony. Photo: DPA.

According to experts in Germany, individuals who have survived an infection with COVID-19, or Sars-CoV-2, are probably “initially immune” to the pathogen. 

As of Monday morning, Germany had over 100,000 confirmed coronavirus cases and over 1,500 deaths, according to data from Johns Hopkins University

READ ALSO: Germany plans mass study to track immunity to coronavirus

We already know that individuals develop antibodies after being infected with the novel coronavirus, explained virologists Melanie Brinkmann, from the Helmholtz Center for Infection Research in Braunschweig, and Friedemann Weber from the Institute for Virology at the University of Gießen.

Based on what we know from similar viruses, the body responds to infection by building antibodies to prevent reinfection, they said. 

Testing for the antibodies

According to Berlin virologist Christian Drosten, it takes about 10 days for antibodies to form after a person is infected with the novel coronavirus.

A blood test can then determine whether or not a patient has developed antibodies, “regardless of whether they had a severe, mild, or completely unnoticed infection,” Drosten said in an NDR podcast last week. 

Even those who have had a completely unnoticed infection will test positive for the antibody.

Knowledge of a past infection is also important to give people with existing immune protection the “green light” to return to work and ease social distancing.

Germany is currently considering so-called “immunity passports” which would allow people to return to a normal life sooner – or even volunteer to help coronavirus patients due to the lower risk that they face.

How long does immunity last? 

A researcher in Braunschweig is exploring antibody development with the novel coronavirus. Photo: DPA. 

Experience with other coronaviruses in humans suggests that the immune protection will last for one to two years after infection. 

“In all likelihood, someone who has been infected with the Sars-CoV-2-Virus is protected from renewed infection for at least a few years,” said Thomas Kamradt, President of the German Society for Immunology.

Still, it is not possible to know this for certain, since the antibody tests are just now coming out and long term studies are not possible given that the virus has only been known for a few months.

The amount of time that a person would have protection from reinfection depends on the rate at which the concentration of the antibodies in the blood, known as the antibody titer, decreases. The higher the concentration, or titer, the higher the number of antibodies, and thus the stronger the protection from renewed infection. 

READ ALSO: How German scientists hope to find answers in country's worst-hit spot

According to Kamradt, it would be “extremely unusual” if the antibodies produced against the novel coronavirus did not protect from renewed infection. 

However, Matthais Orth, Medical Director at the Institute for Laboratory Medicine at the Marienhospital Stuttgart, noted that it is not yet possible to say for certain whether or not the antibodies will protect against reinfection. 

There is also uncertainty about what concentration of antibodies is necessary to protect against renewed infection.

Different disease courses 

According to Brinkmann and Weber, it will also be interesting to study the antibody titers of people with different experiences with the disease. 

This will also clarify the question of whether individuals with particularly difficult courses with the virus have formed antibodies at all or, as they put it: “Was the course so difficult precisely because there were no antibodies formed yet?” 

They hope that further research will also answer the question of when specific antibodies are formed in the course of the infection. 

Giving the “green light” 

Brinkmann and Weber also believe it is very important to identify reliable antibody tests and use them across a wide area. It is essential to identify the undisclosed number of unrecorded cases. 

That would help to recognize how many individuals have already had the infection unnoticed, and therefore how high the basic immunity of the population is already. 

According to statistical projections, around 60 to 70 percent of the population must be infected before the pandemic wave comes to a standstill on its own – without protective vaccination. 

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EXPLAINED: The new rules around getting a sick note over the phone in Germany

Due to high Covid infection numbers throughout the summer, it’s now possible to get a sick note from a doctor over the phone again for some illnesses. Here’s what you need to know.

EXPLAINED: The new rules around getting a sick note over the phone in Germany

What’s happened?

In spring 2020, German authorities changed the law so that people with a mild upper respiratory tract illness, such as the common cold, were able to get an incapacity to work certificate or AU-Bescheinigung by simply calling and speaking to their GP.

The rule was extended several times and finally reversed on June 1st this year due to falling infection figures. Since then people have had to go back to the practice – or do a video call if the doctor’s office has that system in place – to get a sick note.

Now, due to a decision by the Joint Federal Committee, the regulation has been reintroduced and patients can call their GP again for a sick note.

Can I get a sick note over the phone for any illness?

No. As before, the regulation only applies to patients suffering from a mild upper respiratory tract illness. Though Covid has not explicitly been named in the announcement, it seems that it is intended to be covered by the regulation.

If the doctor is convinced that the patient is unfit for work after a telephone consultation, then they can issue a sick note for up to seven days.

READ ALSO: EXPLAINED: The changes around doctor’s notes in Germany you should know

If the symptoms persist after seven days, the certificate can be extended once more for another week.

Why now?

According to the Chairman of the G-BA, Josef Hecken, the regulation has been introduced now as a response to rising Covid numbers and in anticipation of the cold and flu season in the coming months: “We want to avoid full waiting rooms in doctors’ offices and the emergence of new infection chains,” he said.

The telephone sick leave rule is a simple, proven and uniform nationwide solution for that, he said. The rule is also necessary because video consultation hours are not yet available everywhere.

What else should I know?

The health insurer DAK is calling for telephone sick leave in the case of light respiratory diseases to be made possible on a permanent basis in Germany. DAK’s CEO Andreas Storm said that this should “not always be up for debate, because it has proven itself.” 

READ ALSO: Everything you need to know about making a doctor’s appointment in Germany

The social association VdK also welcomed the reintroduction of the rule. The VdK’s President Verena Bentele said that the regulation would help to protect high-risk groups in particular from potential infections.

What are the rules to know about sick notes in Germany?

Germany has a strict system in place. If you are sick, you need to give your employer a Krankmeldung (notification of sickness) before the start of work on the first day (of your illness).

However, you also need to hand in a Krankschreibung (doctor’s note) on the fourth day of your illness. Some employments contracts, however, require you to submit a sick not earlier than the fourth day so check with your boss or HR on that point.