Corona disease course: How COVID-19 disease progress

COVID-19: Overview of possible courses of SARS-CoV-2 infections

The course of the disease in COVID-19 is rather unspecific and varies widely. The extent of a SARS-CoV-2 infection ranges from asymptomatic courses through a moderate, flu-like clinical picture to severe and life-threatening courses that require intensive care. This article gives an overview of possible disease courses.

The individual forms of a COVID-19 disease differ very strongly in some cases. Initial studies indicate that around 43 percent of all SARS-CoV-2 infections are symptom-free. The data subjects do not even notice that they are infected. Among the laboratory-confirmed cases, around 80 percent of all COVID-19 cases were mild. 14 percent of the confirmed cases were severe, but not life-threatening, and around six percent of the cases were critical to life-threatening.

Corona symptoms: how is COVID-19 noticeable?

When symptoms arise, around 80 percent of those affected have only mild cold symptoms with chills and sore throats. Over 60 percent of sufferers notice odor and taste disorders. According to the Robert Koch Institute (RKI), around every second person who is ill reports cough. 42 percent of those infected had a fever, with around one in five people suffering from a cold. Pneumonia (pneumonia) occurs in three percent of cases. Other complaints that can occur with COVID-19 are according to the RKI:

  • Shortness of breath,
  • Headache and body aches,
  • Loss of appetite,
  • Weight loss,
  • Nausea and vomiting,
  • Stomach pain,
  • Diarrhea,
  • Conjunctivitis,
  • Skin rash,
  • Lymph node swellings,
  • Apathy,
  • Drowsiness (somnolence).
  • COVID-19 incubation period

    The incubation period, i.e. the time between infection with the virus and the first symptoms, averages between five and six days for COVID-19. Overall, the incubation period ranges from one day to 14 days, which is why quarantine should be at least two weeks if a coronavirus infection is suspected.

    SARS-Cov-2 infectivity

    According to the RKI, the risk of infecting other people when you are ill begins two days before the symptoms begin. The highest level of infectivity was reached the day before the first symptoms started. How long you have been infectious as a patient has not yet been finally clarified. Initial investigations showed that swab samples from the throat contained reproductive viruses up to four days after the onset of symptoms. Infectious viruses could be detected in the sputum (lung secretion) up to the eighth day after the onset of symptoms.

    Corona without symptoms

    In order to identify the undisclosed number of infected people, it is important to know the proportion of asymptomatic courses. Large-scale antibody tests of the population are required, which should start in May. However, a research team from Imperial College London has already tested almost the entire population in the Italian village of Vo with 3,304 inhabitants and thus obtained a first impression of the proportion of asymptomatic courses.

    The village was cordoned off at the time of testing. At the beginning of isolation, 85.9 percent of the population and at the end of isolation another 71.5 percent of all people living there were tested and at the same time asked about symptoms. This showed that 43.2 percent of all SARS-CoV-2 infections that occurred in Vo during the study period had no symptoms. The virologist Professor Dr. Christian Drosten was impressed by the results. "I think that's a number you can work with in the future," he said in his NDR podcast. Further information can be found in the article: Corona without symptoms possible?

    Mild COVID 19 gradients

    The mild and moderate course of the disease includes all courses without signs of pneumonia or with mild pneumonia without shortness of breath and the need for oxygen supply. As mentioned above, 80 percent of all laboratory-confirmed COVID-19 courses fall into this category. Those affected usually cure the disease in home quarantine. After one to two weeks from the onset of symptoms, the disease is considered to be over if there is no severe course.

    Severe COVID-19 courses

    Around 14 percent of all laboratory-confirmed COVID-19 diseases are difficult. These courses usually have pneumonia that affects more than half of the lungs. Analyzes of Chinese case series showed that pneumonia can manifest itself two to seven days (on average four days) after the onset of the first symptoms.

    Severe courses are characterized by symptoms such as shortness of breath and shortness of breath and require care in the hospital with additional oxygen supply. If the severe course is under control, it is not considered life-threatening unless the condition worsens. On average, those affected are hospitalized five days after the onset of symptoms and remain there for ten days for treatment.

    Critical COVID-19 courses

    In six percent of the laboratory-confirmed cases, the course is critical to life-threatening. These courses have a high risk of causing lung failure, septic shock, or multiple organ failure. Many of these sufferers need mechanical ventilation. A critical course of the disease can last for up to seven weeks.

    So-called acute respiratory failure syndrome (ARDS) occurs in many critical courses. Chinese case series show that ARDS often occurs eight to nine days after the onset of the disease.

    COVID-19 death rate

    The exact death rate cannot be determined due to the inaccurate number of unreported cases. First studies, such as the Heinsberg study by Professor Dr. Streeck, suggest that 0.3 to 0.5 percent of all infected die from COVID-19. The cases with fatal consequences are mainly people over the age of 70 and people with previous illnesses, especially with heart diseases, diabetes, obesity and organ damage, or transplanted organs. In addition, the latest study results from China indicate that men die of COVID-19 more often than women. (vb)

    Author and source information

    This text corresponds to the requirements of the medical literature, medical guidelines and current studies and has been checked by medical doctors.

    Graduate editor (FH) Volker Blasek


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    Video: What Coronavirus Symptoms Look Like, Day By Day (January 2022).