The aim of vaccination is to achieve or maintain basic immunity.

For some diseases, a single vaccination is enough to give basic immunity. With COVID-19, more than one vaccination is necessary.

The effectiveness of a vaccination can decrease after a period of time. A booster vaccination can increase and renew the protection given by the vaccine when its effectiveness is wearing off.

The frequency at which the various booster vaccinations should be given, and the interval that should be left between them, both vary depending on the disease and the vaccine.

An additional factor in the case of the SARS-CoV-2 vaccination is that the virus can mutate and the resulting virus variants can react to the vaccines in different ways.

For coronavirus vaccinations, STIKO (Germany’s Standing Committee on Vaccination) at the Robert Koch Institute (RKI) continually monitors the available data on the efficacy of the vaccines and adjusts its recommendations accordingly.

The Share to Care initiative provides evidence-based information about infection risks and the characteristics of the illness in vaccinated and unvaccinated people.

Further information about booster vaccinations is available from the federal government.

Vaccines are placed in different categories depending on how they are made and how they act.

mRNA Vaccines

mRNA vaccines against COVID-19 contain parts of the hereditary material of the SARS-CoV-2 virus in the form of messenger-RNA (mRNA for short). In this form, the vaccines carry the instructions for making the so-called spike protein, one of the proteins on the surface of the SARS-CoV-2 virus. When someone is vaccinated, the cells in their body start to make this protein which then stimulates an immune response. The mRNA in the vaccine does not enter the cell nucleus, the place where our own hereditary information is kept, and is quickly degraded by the body. It therefore has no effect on the person’s own genetic material.

Vector vaccine

Vector vaccines (from the Latin “vector” meaning “bearer”) are based on viruses that are harmless for humans (such as adenoviruses). These are genetically engineered so that their genetic material contains the building instructions for parts of another virus. In COVID-19 vaccines, the vector viruses contain the gene for making the spike protein on the surface of the SARS-CoV-2 virus. When someone is vaccinated, the cells in their body start to make this protein which then stimulates an immune response.

The adenoviruses used as vectors cannot reproduce in the body and are destroyed by the body within a short time.

Inactivated vaccines

Inactivated vaccines are also known as killed vaccines. They contain either killed pathogens or parts of pathogens. These are recognized by the immune system as foreign material and can thus stimulate an immune response without causing the illness itself.

As intensive research continues it is likely that more types of vaccine against COVID-19 will also become available. The World Health Organization (WHO) provides an overview of the current state of vaccine development.

Further information about COVID-19 vaccines is available on the Federal Health Ministry’s websites infektionsschutz.de and gesund.bund.de and from the Robert Koch Institute (RKI).

The Share to Care initiative provides evidence-based information about infection risks and the characteristics of the illness in vaccinated and unvaccinated people.

The different ways in which the illness is expressed in children and adults suggest that children's immune systems are better able to fend off SARS-CoV-2 infection than are those of adults.

Currently, the exact reasons for the different immune responses are still being investigated. According to a study carried out by researchers at Berlin’s Charité hospital, one of the explanations is that the immune cells in the airways are generally more active in children than in adults and are therefore better able to recognize and combat invading viruses.

Further information about the illness in children is available on the website infektionsschutz.de which is run by BzGA (Federal Centre for Health Education).

COVID-19 carries some level of risk for everyone. However, various different factors can increase the risk of severe illness.

People with weakened immune defense and very obese people (with BMI over 30) are at particular risk of severe illness.

The high-risk groups also include people aged over 60 years old and people with certain pre-existing conditions. Those with diabetes are particularly endangered while those with cancer and diseases of the cardiovascular system, lungs or liver also constitute high-risk groups.

In addition, people with some disabilities, certain genetic rare diseases or severe mental illness can be at increased risk of severe illness with COVID-19.

The section COVID-19: An ABC lists the risk factors for severe illness.

Further information about high-risk groups and risk factors is available on the Federal Health Ministry’s websites infektionsschutz.de and gesund.bund.de.

Information is available in different languages from the World Health Organization (WHO).

The first person to consult about health matters is normally your family doctor. He/she can perform basic examinations and make a diagnosis.

With mild to moderate COVID-19 it is not usually necessary to consult other doctors. As the illness progresses, the type and severity of the symptoms may call for examinations and treatment from a variety of other specialists such as a pulmonologist (lung specialist) in the case of breathing problems or a neurologist (nerve specialist) for problems with concentration, attention, fatigue and the senses of taste and smell.

When COVID-19 patients are treated in hospital, various different specialists are usually involved.

Please remember: if you suspect that you have COVID-19 it is best to get medical advice on the phone rather than going to the doctor's office in person. That way you avoid infecting other patients.

If you have acute COVID-19 symptoms you should call your doctor’s office and ask what rules currently apply with regard to isolation. The medical staff there can tell you what to do next.

If you need additional examinations and treatment and are looking for a specialist near your home, you can use the search options offered by the German Medical Association (Bundesärztekammer), the information services of the regional medical associations (KV) and the list compiled by the Bertelsmann Foundation.

When the illness is mild to moderate, people usually recover in two to three weeks. When you are infected with SARS-CoV-2 you should support your immune system by drinking plenty of water, getting enough sleep, avoiding exertion and stress and eating a balanced diet.

If the illness is severe it usually takes considerably longer to make a full recovery. This applies particularly to patients who are treated in hospital and receive artificial ventilation.

After recovering from COVID-19 you can take a PCR test. This will show whether the infection has cleared and the viral load is so low that you are no longer infectious.

But a negative test result does not automatically mean you are fully cured. It can happen that some symptoms of the illness, such as respiratory distress, exhaustion or impaired senses of taste and smell, persist for weeks or months after a negative test result.

When the symptoms are still present three months after a SARS-CoV-2 infection and they last longer than two months, the condition is known as long COVID or post-COVID syndrome.

Further information about the possible long-term effects of COVID-19 is available at infektionsschutz.de (the website of BZgA) and at the Health Ministry’s website gesund.bund.de.

Information about COVID-19 is available in different languages from the World Health Organization (WHO) and in English from Pfizer Inc.

COVID-19 can cause a variety of longer-lasting symptoms such as problems affecting the heart, nervous system and/or lungs and also problems of a psychological nature.

When the symptoms are still present three months after a SARS-CoV-2 infection and they last longer than two months, the condition is known as long COVID or post-COVID syndrome. (The official medical term is “post-COVID-19 condition” but it is commonly referred to as long COVID.)

Typical long COVID symptoms are:

• breathlessness, respiratory distress
• neuropsychological symptoms such as forgetfulness and difficulty concentrating
• headache
• persisting tiredness, fatigue
• quickly becoming exhausted after physical exertion

Other possible late effects of COVID-19:

• impaired senses of taste and smell
• sleep problems
• depressed mood and anxiety
• rapid heartrate, irregular heartbeat
• gastrointestinal symptoms, allergies, intolerances

It is thought that up to 15% of those who catch COVID-19 will go on to develop long COVID. The precise causes of longer-lasting symptoms after COVID-19 are still not clear. The risk is higher after severe illness than after mild illness.

Further information about long COVID and post-COVID syndrome is available in a patient guide produced by AWMF (working group of medical associations), at the info portal from BZgA (longcovid-info.de) and at the Federal Health Ministry’s website gesund.bund.de.

When your antigen home test or rapid test is positive, it is highly likely that you are infected with SARS-CoV-2. You should avoid social contact and inform the people you have been in contact with in the past few days. A PCR test can confirm whether you are really infected.

When your PCR test result is positive, the testing laboratory informs the relevant local health authority (Gesundheitsamt) and you have to isolate. This means you are only allowed to leave your home in an emergency and you are not allowed to have visitors.

After a positive PCR test it is important to avoid infecting anyone else. When you are isolating at home, you should reduce your contact with other people in your household as much as possible, keep your distance, wash your hands often, wear a mask at home and air the rooms regularly.

The length of time you have to spend isolating and the time that close contacts have to spend in quarantine can be different in different parts of Germany and have been changed several times during the pandemic. Please check on the current rules in your particular federal state. More information can be found at infektionsschutz.de (website of BZgA, the Federal Centre for Health Education).

Most infected people recover from the illness at home. If need be, you can take medicines to relieve the symptoms and reduce your fever or calm the cough. In certain cases it can also be helpful to take antivirals early on in the illness to avoid becoming seriously ill. You should discuss the treatment options with your doctor as soon as you receive the result of the PCR test.

You should also consult a doctor if the symptoms worsen, or do not get better, after a week. Ask how the treatment will proceed and whether it needs to happen in hospital.

When children become infected with SARS-CoV-2, many develop only mild symptoms or no symptoms at all. This means it is often hard for parents to recognize when a child has COVID-19. You should nevertheless watch out for typical symptoms in your child such as coughing and fever.

A test can give you a definite answer. For further information about COVID tests, go to the Examinations section.

The symptoms are usually less pronounced in children than in adults. COVID-19 in children is usually mild or without symptoms. If symptoms do occur they often consist of a cough, fever and/or a runny nose. In such cases the illness is similar to a cold.

However, it can happen that children and young people develop long COVID, experiencing longer-lasting symptoms such as exhaustion, concentration difficulties or muscle pain.

In very rare cases, children can develop a condition known as PIMS (Pediatric Inflammatory Multisystem Syndrome) or MIS-C (Multisystem Inflammatory Syndrome in Children) a few weeks after recovering from COVID-19.

There is an increased risk of more severe illness in infants and in children who already have lung disorders and/or cardiovascular illness. The Robert Koch Institute (RKI) provides a list of relevant pre-existing conditions (the list is to be found below the question “Welchen Kindern und Jugendlichen wird die COVID-19-Schutzimpfung besonders empfohlen?”)

Further information about the expression of the illness in children is available at the Federal Health Ministry’s website infektionsschutz.de and from the Robert Koch Institute (RKI).

The World Health Organization (WHO) provides extensive information about COVID-19 in children and young people in various languages.