Coronavirus information
10:52 · 28 February 2023

Long-COVID – What are the long-term effects of a COVID-19 infection?

Not only serious, but also mild COVID-19 or even an unnoticed infection, can lead to long-term effects on people’s health. Find out more about the potential long-term effects of a SARS-CoV-2 infection.

More and more people are suffering from long-COVID

Virus infections can be tricky. Occasionally, those affected continue to suffer from symptoms long after they have recovered from an infection. Long-term effects are also known to occur in other infectious diseases (Spanish Flu, MERS, SARS); however, recent studies suggest that long-term effects occur more frequently and for a longer duration than, for instance, after influenza. The coronavirus is considered a multi-organ virus, which affects not only the lungs, but also numerous other organs, such as the kidneys, heart, liver and brain.

From difficulties breathing to fatigue: Potential Long COVID symptoms 

The COVID-19 illness that is triggered by coronavirus and the longer-lasting health issues associated with the infection or illness are currently undergoing intensive research. 

In October 2021, the World Health Organization (WHO) published the first case definition of the long-term effects of COVID-19 illness (post-COVID-19). Additionally, under the leadership of the German Respiratory Society (Deutsche Gesellschaft für Pneumologie und Beatmungsmedizin e.V./DGP), 16 medical societies compiled a guideline for medical personnel regarding Long COVID and post-COVID. On that basis, a patient guideline was developed that describes frequent symptoms of Long and post-COVID and explains how those affected can manage these – albeit according to the authors, much is still unknown in this regard.

Some of those infected notice very little or even nothing at all of their coronavirus infection. In a mild disease progression, the COVID-19 illness can last between two to three weeks. The duration of illness varies greatly from person to person and is also affected, for instance, by whether they have already been vaccinated against COVID-19. The acute phase of the disease usually lasts a maximum of four weeks. In severe cases, the acute phase of the disease can last twice as long. After ICU treatment, long-term organ-specific sequelae have often been observed. Yet even people who do not fall severely ill may exhibit or newly develop health-related symptoms beyond the acute phase of their disease. According to the current guidelines, whether we refer to “Long COVID” or “post-COVID” depends on the duration that the symptoms persist:

  • “Long COVID”: When symptoms have not yet subsided after more than four weeks following the infection or illness.
  • Or “post-COVID-19 syndrome”: When symptoms that cannot be explained otherwise still persist or even newly emerge more than twelve weeks after the infection or illness.

Often a focus is on symptoms with uncertain causes such as constant fatigue, shortness of breath and loss of concentration or memory (“brain fog”). Other frequent symptoms are coughing, chest pains, muscular pains, mental health disorders such as depression or anxiety disorders, smell and taste disorders, sleep disorders, impaired speech and fever. Even organ damage – such as of the heart, lung, kidney or brain – is possible with mild disease progressions. Additionally, the loss of taste or smell, typical of coronavirus illness, can also persist long after recovery. Accordingly, health impairments that have been observed following the acute phase of the disease comprise a broad range of symptoms. Reliable, representative data concerning the share of infected people experiencing long-term effects are not yet available. The German Respiratory Society (Deutsche Gesellschaft für Pneumologie und Beatmungsmedizin/DGP) estimates that up to 15 percent of all those infected are dealing with Long COVID and up to 2 percent with post-COVID.

Fatigue – a creeping exhaustion

Fatigue refers to a sudden and severe onset of exhaustion. Not seldom does fatigue occur as an accompanying symptom of chronic illnesses such as cancer or rheumatism. Fatigue can also appear after viral infections such as COVID-19. The causes are not yet sufficiently understood. Frequently it is not the virus itself that is to blame, but the immune system which has not yet come to rest following the infection.

Special risk factors for Long COVID

Regarding risk factors, underlying chronic and mental health conditions and a serious COVID-19 disease progression appear to be conducive toward developing Long COVID. Long COVID also appears to occur particularly among young to middle-aged adults and socially disadvantaged people. On the whole, women appear to be less likely to develop Long COVID than men. Other risk factors include a previous infection with the Epstein-Barr virus and the presence of diabetes mellitus. On account of their profession, those working in healthcare also appear to be exposed to a higher risk of SARS-CoV-2 infection, and thereby also of developing Long COVID. A personal account from Germany about the lengthy recovery process can be found here.

The “Zoe COVID Study” published in the The Lancet Infectious Diseases journal suggests that full vaccination not only provides protection from severe disease progressions, but also, in case of an infection following vaccination, from long-terms effects of a COVID-19 infection.

According to a metastudy by the UK Health Security Agency comprising 15 different studies, the likelihood of developing Long COVID following a coronavirus infection is lower among vaccinated people than among unvaccinated people. This protective effect would still linger for six months after the vaccination. Additionally, there were also indications that unvaccinated people suffering from Long COVID following an infection, still benefited from vaccination even if they only got vaccinated after the infection. On average, they showed fewer and less severe Long COVID symptoms than those who remained unvaccinated.

Children and Long COVID – initial findings

Long COVID can also occur among children and adolescents. However, it is still unclear how often and how severely they are affected. Here study findings sometimes contradict one another. 

According to the German Professional Association of Paediatricians (BVKJ), initial study findings suggest that children who had a serious disease progression can suffer from persisting symptoms such as fatigue, concentration problems or muscular pain. An article in the “Nature” journal states e.g. that statistics from England indicate that around 10 percent of all children and adolescents up to the age of 16 still suffered from at least one symptom of the disease five weeks after their COVID-19 diagnosis. Data from Russia indicated that one in four children treated in hospital still had symptoms five months after having been discharged. 

Several larger studies, including a study by the Dresden University Children's Clinic (Dresdner Universitäts-Kinderklinik) comparing various symptoms among children with and without a SARS-CoV-2 infection, appear to suggest that there are no significant differences between these two groups of children. One conclusion that could be drawn is that besides the virus itself, among children above all else the measures to contain the pandemic (such as closing schools and limiting contact with others) also play an important role and are linked to health issues. 

In summary, many questions regarding the spread and treatment of Long COVID among children and adolescents still remain unanswered. Several research projects, including the “LongCOCid” project funded by the Federal Ministry of Education and Research and carried out by the University Hospitals of Magdeburg, Jena and Ilmenau, are attempting to find answers to these questions. For instance, “LongCOCid” addresses the question of whether children and adolescents are particularly at risk of developing allergies and autoimmune diseases following Long COVID. Find more information here.

Long COVID treatment: from your general practitioner to self-help groups

Many aspects about late symptoms of COVID-19 and lasting damage have not yet been clarified. At the same time, steps are being taken to help those affected and to gain further insights. The primary points of contact for patients with Long COVID are usually family doctors (GPs). Together with specialists in private practice, these doctors form solid networks that can ensure interdisciplinary outpatient care. Some regions also already possess general practitioners and specialists that focus on COVID, whom patients can also use as ports-of-call. 

Furthermore, especially some university hospitals have already installed Long-COVID outpatient clinics to treat patients with long-term effects. 

At this time, no causal therapy of Long and post-COVID exists. The treatment is currently symptomatic. That is why rehabilitation is particularly important with Long COVID. Since multiple organ systems are usually affected, frequently several medical specialties are incorporated in the treatment, in particular general medicine, paediatrics and pulmonology, neurology, psychosomatics, psychiatry as well as psychotherapy. The Federal Association for Rehabilitation (Bundesarbeitsgemeinschaft für Rehabilitation)provides an overview of rehabilitation clinics offering services for Long and post-COVID. Furthermore, the World Health Organization (WHO) offers a leaflet to assist in the rehabilitation and follow-up treatment of Long COVID. 

There are also self-help groups. The website of the national contact and information point to inspire and support self-heal groups NAKOS provides an initial overview of available initiatives. 

Long COVID Infoportal

Learn more about the current state of knowledge regarding Long COVID on the Long COVID information page of the Federal Centre for Health Education (BZgA). Moreover, the page also offers ports-of-call for more detailed information and support.