The Public Health Agency of Sweden
Updated 7 May 2020

The virus and the illness

The virus and the illness

  • Listen

    This information is available from the WHO.

    Updated: 5/14/2020 11:44:19 AM

  • Listen

    COVID-19 is the official name, decided by the WHO, for the disease caused by the new coronavirus SARS-CoV-2. COVID-19 is an acronym for coronavirus disease 2019.

    Updated: 5/13/2020 11:17:29 AM

  • What are the symptoms of COVID-19?

    In most people, COVID-19 manifests as a respiratory tract infection, and many different symptoms may be present. It is not possible to distinguish COVID-19 from other infections from only the symptoms – a laboratory test is required.

    Among the reported symptoms are:

    • Cough
    • Fever
    • Difficulty breathing
    • Runny nose
    • Blocked nose
    • Sore throat
    • Headache
    • Nausea
    • Muscle and joint pain

    A person falling ill with COVID-19 may experience one or more of these symptoms. It is fairly common to lose one’s sense of smell and taste for some time during an infection in the upper respiratory tract. Diarrhoea has also been reported as a symptom.

    Most people get mild symptoms and can recover at home without professional medical care. The symptoms often appear gradually. Some people get a severe form of the illness, with breathing difficulties and pneumonia.

    The list of symptoms may be adjusted over time, since we update our information as new knowledge becomes available, e.g. in scientific studies or from the WHO.

    The time between getting infected and developing symptoms (the incubation period) seems to be between 2 and 14 days. Most people develop symptoms after 5 days.

    It is very important that you stay at home if you feel ill. If you can no longer manage the illness on your own, please call 1177 for medical advice (available in English).

    Updated: 4/24/2020 1:55:51 PM

  • Listen

    Since COVID-19 can cause mild symptoms, it can be difficult to distinguish between the disease and other types of illness, such as hay fever.

    Stay home even if you have mild symptoms like a runny or blocked nose, a slight cough or a sore throat. Take your usual allergy medication. If the symptoms do not get worse, your medication relieves the symptoms, and your judgement is that the symptoms are likely to be caused by allergy, you do not need to remain at home.

    If you experience new symptoms which you do not associate with your allergy, or if you get a fever, you should stay home until you are free from symptoms, and then an additional two days.

    Updated: 5/18/2020 1:31:19 PM

  • Listen

    The coronavirus (SARS-CoV-2) causing COVID-19 is mainly transmitted between people via respiratory droplets or secretions from the respiratory tract. Transmission via droplets happens when an infected person coughs or sneezes and the droplets reach mucous tissue in someone's eyes, nose, or mouth. The droplets fall to the ground within approximately one meter (3 ft) from the source.

    The virus can be transmitted via contaminated surfaces, so-called indirect contact transmission, but the risk of getting infected via contaminated surfaces is considered to be very low. There are no indications that anyone has been infected with the new coronavirus from touching contaminated surfaces or items.

    It is currently not clear how long the virus can survive on surfaces and items. The material itself and conditions in the surrounding such as humidity, temperature, and sunlight will determine how long the virus is viable. Further studies will clarify the importance of transmission via surfaces and items for the overall spread of COVID-19.

    You can decrease the risk of transmission by keeping a distance from other people in public spaces, washing your hands often with soap and warm water, avoiding touching your face (eyes, nose and mouth), and by staying at home if you are ill.

    Updated: 5/22/2020 8:21:09 AM

  • Listen

    The incubation period, i.e. the time between getting infected and developing symptoms, seems to be between 2 and 14 days.

    Most people develop symptoms after around 5 days, but individual cases may deviate from this pattern.

    Updated: 5/18/2020 1:32:40 PM

  • Listen

    Most people infected with COVID-19 get mild symptoms of respiratory tract illness and recover without medical treatment.

    Some people develop a more severe form of disease, for example pneumonia. Knowledge about the virus and the disease increases continuously.

    Updated: 5/13/2020 11:23:30 AM

  • Listen

    Most people with mild symptoms of infection (fever and a cough) get well after about two weeks but it can take significantly longer, weeks or months, to fully recover after having been severely ill.

    Patients with severe illness, who have been in hospital care, often need a longer period of time to recover. Some patients feel fatigued for quite some time after recovery.

    Symptoms like dry cough and the loss of smell and taste may remain for some time even after having recovered from COVID-19.

    The risk of transmitting COVID-19 is probably highest at the beginning of the disease. Stay at home if you are ill. If you have tested positive for COVID-19 you should stay at home for at least seven days after falling ill including two days with no fever. If you have developed more severe symptoms stay at home for at least 14 days after falling ill, and if you belong to the group who have been in hospital care, an individual assessment by your treating physician needs to be done.

    The currently available knowledge about how long COVID-19 lasts comes from the WHO "Report of the WHO-China Joint Mission on Coronavirus Disease 2019 (COVID-19)".

    Updated: 7/15/2020 4:03:00 PM

  • Listen

    The majority of those infected get well again. A small proportion of the population, of which most belong to a risk group, develop a severe form of the disease. There is so far no data on remaining chronical conditions.

    Updated: 7/15/2020 4:03:23 PM

  • Listen

    Globally, it is estimated that 0.5–1 percent of those who are infected with COVID-19 die. There is a clear relationship between increased fatality risk and older age: the older you are, the higher the risk.

    There are only a few peer-reviewed studies of the infection fatality rate of COVID-19, i.e. the share of infected who die, which means that this might change as new knowledge becomes available.

    A study by The Public Health Agency of Sweden estimates the fatality rate in the Stockholm region to 0.6 percent, for all ages. The fatality rate among those 70 years or older is 4.3 percent, whereas it is 0.1 percent among those younger than 70 years.

    The infection fatality rate of COVID-19 in Stockholm – Technical report

    Updated: 5/13/2020 11:26:54 AM

  • Listen

    Some groups of people may get more severe symptoms if they are infected by COVID-19. For example, they may get pneumonia or shortness of breath. The older people are, the greater the risk of serious illness and death. If people also have other health conditions, the risk is even greater. Men are approximately twice as likely as women to become seriously ill and die.

    The risk of becoming seriously ill increases gradually with age:

    • People aged 60-70 are twice as likely to become seriously ill as people aged 50-60
    • People aged 70-80 are five times more likely to become seriously ill than people aged 50-60
    • People over 80 are at greatest risk. They are twelve times more likely to become seriously ill than people aged 50-60

    70 or over

    The list below is of health conditions that, added to increasing age, can further increase risk. The higher up they appear in the list, the greater the increased risk.

    • Organ transplants
    • Blood cancers – existing or previous
    • Neurological conditions (e.g. MS, Parkinson’s, myasthenia gravis)
    • Obesity (risk increases with increased levels of obesity)
    • Diabetes (less risk if it is well controlled)
    • Ongoing cancer treatment
    • Chronic pulmonary diseases (including asthma, but risk very marginal if well controlled)
    • Stroke/dementia
    • Other immunosuppressive conditions or treatment
    • Liver disease
    • Impaired kidney function
    • Cardiovascular disease

    High blood pressure on its own does not appear to increase the risk at all and therefore no longer appears on the list.

    Under 70

    People under 70 may also be at increased risk of serious illness if they have:

    • one or more of the health conditions listed above
    • a health condition that increases the risk of serious illness if they get a respiratory infection

    Children are very unlikely to become seriously ill, even if they have one of the conditions or illnesses that increase the risk for adults and older people.

    New information is being added continuously, and the Public Health Agency of Sweden is monitoring developments and updating its information in line with the most recent knowledge.

    Updated: 6/15/2020 11:16:51 AM

  • Listen

    There are few studies of pregnant women with COVID-19, and only a limited amount of information is available. At present, there are no indications that pregnancy is a risk factor for severe illness from COVID-19.

    Risk factors such as severe obesity, high blood pressure or diabetes might increase the risk of severe illness. Therefore, pregnant women who have any of those risk factors should be careful and consult with their midwife or doctor and limit close contact with people outside of the household as much as possible.

    It is important to avoid getting infected before delivery because a respiratory infection towards the end of the pregnancy can be difficult and might imply risks to the pregnant woman.

    We recommend that pregnant women take extra precautions from week 36 and follow our recommendations thoroughly.

    Mother-to-child transmission of COVID-19 during pregnancy is unlikely. Children can be infected with COVID-19 but severe symptoms are very rare in newborn babies and in children. Therefore, healthy newborn babies do not need to be separated from their mother after delivery due to the risk of transmission.

    According to available studies, breast milk is not a source of transmission of COVID-19 and there is therefore no reason to prevent mothers from breastfeeding.

    Information is also available from the centre for knowledge about infections during pregnancy (in Swedish).

    Updated: 5/20/2020 8:48:56 AM

  • Listen

    It is unclear how long immunity against COVID-19 lasts after an infection. Based on previous experience, there is reason to believe that immunity will last long enough to prevent people from getting infected several times during the same season.

    Updated: 5/13/2020 11:27:37 AM

  • Listen

    Yes, smoking increases the risk of severe illness with COVID-19, according to available studies.

    The fact that tobacco smoking increases the risk of severe symptoms during respiratory tract infections is already well-known from e.g. seasonal influenza.

    Some health benefits of giving up smoking appear quickly, for example increased oxygenation of the blood, lower blood pressure, and improved pulmonary function. For advice and support to stop smoking, contact Sluta-Röka-Linjen (information etc. is available in English and other languages).

    New information and data is added continuously, and the Public Health Agency monitors the situation and updates its advice accordingly.

    Updated: 7/1/2020 12:23:07 PM