General information

Post-COVID condition, post-COVID syndrome, long COVID, post-acute effects of COVID-19. 

What is post-COVID ?

Post-COVID is a condition associated with new and persistent symptoms following COVID-19 infection. In this case, a syndrome is a set of symptoms.
The term “post-COVID” is also sometimes used to refer to the period after hospitalization or after infection with the SARS-CoV-2 virus. In severe cases, patients may need to be admitted for a period of rehabilitation care.
This site is about post-COVID condition or post-COVID syndrome, also known as long COVID or the post-acute effects of SARS-CoV-2.

How do I know if I have post-COVID condition ?

If you had a COVID-19 infection more than 3 months ago and still have persistent symptoms, they may be due to post-COVID condition. On 6 October 2021, the World Health Organization (WHO) issued a definition of post-COVID-19 condition, also known as long COVID: a diagnosis typically made 3 months after infection with the COVID-19 virus, with symptoms that last for at least 2 months and cannot be explained by an alternative diagnosis. In general, unless they are reinfected, people suffering from post-COVID are no longer contagious beyond their period of isolation.

What are the symptoms of post-COVID condition ?

There are many symptoms of post-COVID condition. The most common are intense fatigue or exhaustion, post-exertional malaise, shortness of breath, loss of taste or smell, joint or muscle pain, difficulty concentrating, headaches and anxiety. To learn more, you can read the information on this site and discuss it with your doctor.

How long do the symptoms last ?

Post-COVID symptoms usually improve, although they may fluctuate over time. It is impossible to predict the duration of post-COVID condition.
Studies conducted in Geneva* on persistent symptoms following a COVID-19 infection have shown the following results: 

Six weeks after illness, the following symptoms have been observed :

  • Fatigue (14%),
  • Loss of taste or smell (12%),
  • Shortness of breathe (9%),
  • Cough (6%)
  • Headaches (3%). 

After 7 to 9 months, the following symptoms have been observed :

  • Fatigue (21%),
  • Loss of taste or smell (16%)
  • Shortness of breath (12%)
  • Headaches (10%)
  • Difficulty concentrating or brain fog (6%)
  • Memory loss (6%)
  • Insomnia (6%)
  • Muscle aches (6%)
  • Joint pain (3%)
  • Palpitations (3%)
  • Chest pain or tightness (3%)
  • Neuropathy (2%)

At 12 months, the following symptoms have been observed :

  • Fatigue (16%) 
  • Loss of taste or smell (10%) 
  • Shortness of breath (8.9%) 
  • Headaches (9.8%) 
  • Difficulty concentrating or memory loss (7.4%)  
  • Insomnia (8.9%) 
  • Muscle aches (7.3%) 
  • Joint pain (2,9%) 
  • Palpitations (3.8%) 
  • Chest pain or tightness (6%) 
  • Neuropathy (5.4%) 
  • Dizziness (6.4%) 
  • Digestive symptoms (4%) 
  • Cough (6.5%) 

Omicron variants showed a prevalence of post-COVID symptoms at 12 weeks of 11.7% against 10.4% in PCR negative controls. 

In children, 12 weeks after illness, the following symptoms have been predominantly observed: 

  • Fatigue (24%)
  • Loss of taste or smell (9%)
  • Abdominal pain (19%)
  • Difficulty concentrating (14%)
  • Runny nose (11%)
  • Muscle pain (10%)
  • Difficulties breathing (6%)
  • Headaches (13%)
  • Constipation (5%)

Other symptoms include digestive problems and skin rashes. Studies are continuing in Geneva to assess how persistent symptoms develop over time following a COVID-19 infection. The percentages indicated are based on our studies on post-COVID condition in Geneva.

Link to studies

Prevalence of Symptoms More Than Seven Months After Diagnosis of Symptomatic COVID-19 in an Outpatient Setting

Longitudinal Evolution and Persistence in Outpatient Settings

One-year persistent symptoms and functional impairment in SARS-CoV-2 positive and negative individuals

Post-COVID condition after Omicron infection compared to negative controls 

A population-based serological study of post-COVID syndrome prevalence and risk factors in children and adolescents


What mechanism triggers post-COVID condition ?

The pathophysiology and mechanisms behind persistent symptoms after a SARS-CoV-2 infection are still under investigation. Hypotheses include a dysfunctional immune response that causes persistent symptoms and inflammation that fluctuates over time caused by virus particles or the whole virus. Other hypotheses suggest that vascular changes or changes to blood vessel walls that might cause microclots and persistent symptoms. All these hypotheses are still being studied and have yet to be proven.

Read more: A scientific article on the pathophysiology and diagnosis of long Covid was published in the Swiss Medical Journal on 1st February 2023 :  «Post-Covid : nouveautés 2022 et prochaines étapes».

Authors : Dre Mayssam Nehme, Aurélie Ducrot, Pr Dominique Salmon et Pr Idris Guessous.

What test should I do to find out if I have post-COVID ?

It is important to get an initial diagnosis from either an RT-PCR test or a positive antigen test during the acute phase. If no test is performed during the acute phase, serological detection of antibodies can indicate past infection. Serological testing must be performed at least 3 weeks to a month after the acute phase to detect antibodies. In individuals who do not have a condition affecting the immune system, it is rare not to have a serological trace after the acute phase. There is no specific test for diagnosing post-COVID. The diagnosis is clinical and is based on the persistence of symptoms 12 weeks after infection with SARS-CoV-2.

What if I don’t have antibodies ? 

If serological testing is negative, and especially if the tests were performed in an external laboratory without any detailed information, the tests should be repeated in a reference laboratory (e.g. at the Geneva University Hospitals (HUG)).

What about cellular tests ? 

These tests detect a cellular response to different viruses. They can give positive results in patients who have not been exposed to SARS-CoV-2, possibly due to non-specific reactions or cross-reactions with other coronaviruses. These tests have limited relevance, are not standardized and are therefore not recommended.

Am I at risk of post-COVID ?

Anyone can develop persistent symptoms following a SARS-CoV-2 infection, regardless of age or the severity of the acute phase. Studies conducted at the Geneva University Hospitals (HUG) show an association between being female, the number of symptoms in the acute phase and a higher risk of persistence of long-term symptoms. However, vaccination is associated to a decreased risk of developing a post-COVID condition.

How can I protect myself against post-COVID ?

At present, there is no treatment for post-COVID condition and there are no measures that can prevent it. The best way to avoid persistent symptoms is to avoid infection by following public health recommendations. 

Should I get vaccinated ?

Vaccination against COVID-19 protects everyone, especially vulnerable individuals, and reduces complications. While COVID-19 is benign in most healthy young people, it can sometimes be severe or long-lasting or can have long-term effects. Vaccination reduces the risk of persistent symptoms. The results of a study of 1.2 million people showed that vaccinated individuals had half the risk of persistent symptoms at 28 days after infection compared to non-vaccinated individuals. This potentially indicates that the vaccine can prevent post-COVID symptoms in people who become infected. Similarly studies on the Geneva post-COVID cohort showed that individuals who were vaccinated had less symptoms than those who were not vaccinated including after an infection by the Omicron variant BA.1/BA.2.

In people with post-COVID symptoms who subsequently get vaccinated, the symptoms tend to remain stable post-vaccination in 72% of cases, may improve in 23% of cases and temporarily worsen in 5% of cases. Vaccination is not a treatment for post-COVID symptoms, but it can act as a preventive measure to reduce the risk of post-COVID as well as the risk of another infection.
It is up to individuals to choose the risks they are willing to take. You can find all the information about vaccination on the following web page : vaccination (FR).


Am I at risk of another Covid-19 infection ?

With new virus variants, there is a risk of reinfection. Furthermore, reinfection seems to increase the risk of developing a post-COVID syndrome. Currently, the best way to reduce the risk of reinfection is to follow public health recommendations and get vaccinated.

What factors relieve or worsen symptoms ?

At present, studies have not been able to demonstrate the factors that may trigger, worsen or improve post-COVID symptoms. Symptoms develop in different ways in different individuals. Stress can trigger certain symptoms and slow down recovery. As a general rule, we recommend rest and pacing, or the respect of one’s energy levels. One of the principles of recovery from post-COVID is an interdisciplinary approach to managing the multiple simultaneous symptoms and their impact on daily life to help patients plan, take their time and prioritize.