What is Long Covid?

The SARS-CoV-2 pandemic has affected a great many people over the past two years. Science has made progress in understanding the development and treatment of acute SARS-CoV-2 infection. In recent months, another illness has emerged: the so-called long-term COVID syndrome.

Long Covid describes the effects and long-term symptoms of Covid-19 that persist for weeks or months after the illness. The World Health Organization (WHO) defines long Covid as symptoms that

  • which usually occur three months after the start of Covid-19,
  • which last at least two months and
  • that cannot be explained by another diagnosis.

Studies show two main categories of persistent symptoms in long-term Covid:

  • a larger group with a range of more general symptoms, particularly chronic headaches, tiredness and exhaustion, tingling, numbness and “brain fog”, palpitations and rapid pulse
  • a smaller group of people with respiratory symptoms such as coughing or shortness of breath (this group was initially more likely to have a severe case of Covid-19).

How many are affected by long-term Covid?

More than four out of ten (42 percent) people suffered from long-term COVID symptoms more than a year after their COVID infection. Almost two-thirds (63 percent) stated that their symptoms had impaired their ability to carry out everyday activities.

What are the symptoms of long-term COVID?

Long-term COVID can be prolonged or occur periodically in cycles. For a while, the condition improves, and then worsens again. These long-term effects are not only observed in those who had to be hospitalized or who felt very ill upon initial infection. Persistent symptoms of the coronavirus can include:

  • Headache
  • fatigue
  • Shortness of breath or difficulty breathing
  • Sleep difficulties
  • Anxiety and depression
  • heart palpitations
  • Tightness or pain in the chest
  • Joint or muscle pain
  • Inability to think clearly or concentrate ('brain fog')
  • Changes in the sense of smell or taste
  • Persistent cough

Does a Covid-19 vaccination reduce the risk of long Covid?

Yes – there is ample evidence that vaccination reduces the risk of developing long-term COVID. The UK Health and Safety Authority (UKHSA) analyzed 15 international studies on long-term COVID. These studies found that individuals who contracted COVID after receiving two doses of the Pfizer, AstraZeneca, or Moderna vaccine, or one dose of the Janssen vaccine, were only half as likely to develop long-term COVID symptoms. This study only examined individuals who had contracted the coronavirus. Since vaccination also reduces the risk of contracting COVID, the actual reduction in the long-term risk of COVID through vaccination is significantly greater.

Can Covid-19 cause headaches?

Many studies have shown that Covid-19 can cause headaches. Some people even develop headaches before they notice breathing difficulties. Headaches are among the most common symptoms of Covid-19. Headaches are frequently a symptom of acute viral infections. However, they can also persist even after the virus is no longer active in the body.

Viral infections can worsen pre-existing migraines; attacks may occur more frequently or the pain may last longer than usual. People who suffer from migraines are more likely to develop headaches after a viral infection. Long-COVID headaches may be more common in patients with a history of primary headaches.

Covid-19 can also cause a new, persistent headache that was not present before the infection but continues for some time afterward or is felt constantly. Most patients with Covid-19 report that their headaches improve within two weeks. However, for some, it may take several weeks longer, or the headaches may become chronic.

What do post-Covid-19 headaches look like?

In both clinical practice and research, the terms “post-COVID-19 headache” and “persistent headache after COVID-19” are used. These terms describe all chronic headaches whose onset or worsening is temporally related to a confirmed SARS-CoV-2 infection.

  • A temporal pattern is the persistence of headaches, occurring during the acute phase of infection despite the resolution of other COVID-19 symptoms. The prevalence of headaches during acute COVID-19 infection in various studies ranges from 13.0% to 74.6%. In 81.8% of patients, the headache begins with the onset of COVID-19 symptoms; it is usually bilateral frontal (34.0%–38.1%) or generalized (34.0%–38.8%) and is predominantly described as a pressure-like pain (70.1%–73.7%). More than half of patients report moderate or severe pain (60.6%–75.3%). Headache episodes often last longer than 24 hours, with almost half of patients reporting persistent pain. In half of the cases, the pain follows a diurnal pattern, typically worsening in the evening (24.2%). The pain is often aggravated by physical exertion (12.37%–45.5%) and coughing. The headache is frequently accompanied by sensitivity to light (10.3%–29.3%) and sensitivity to noise (10.3%–27.3%).
  • The second pattern of persistent headaches after Covid-19 is characterized by the worsening and transition to a chronic course of pain in patients who had migraine before COVID-19.
  • The third pattern is daily persistent headaches in patients with no personal history of primary headaches, with the pain beginning after the acute Covid-19 subsides and no headaches occurring during the acute infection itself.

What mechanisms are being discussed regarding the development of Long Covid?

The mechanisms underlying acute SARS-CoV-2 infection have been extensively studied and identified. The precise reasons leading to symptom persistence and long COVID-19 are not yet known. The following mechanisms have been proposed:

  • Consequences of organ damage, extent of the damage and time until recovery of the individual organ systems.
  • Persistence of chronic inflammation or formation of autoantibodies.
  • Persistence of the virus in the body in people with altered immunity, new infection or relapse.
  • Effects of hospital stays, complications related to SARS-CoV-2 infection, or complications related to comorbidities or adverse effects of the medications used.
  • Psychological consequences such as post-traumatic stress.
  • Social and financial impacts.

How is a diagnosis of Long Covid made?

Long COVID is diagnosed based on clinical symptoms and disease progression. A cross-disciplinary approach and multidisciplinary care are essential. Risk factors that can lead to persistent symptoms after an acute infection include older age, severity of the acute phase, obesity, female sex, comorbidities, asthma, and experiencing more than five symptoms during the acute phase. However, individuals without these risk factors can also develop long COVID. Symptoms often overlap with those of other illnesses. Therefore, long COVID is diagnosed when the symptoms cannot be explained by other medical conditions.

How is long-term Covid treated?

Long-term COVID and the nature of the symptoms necessitate a multidisciplinary diagnostic assessment and complex, interdisciplinary, multimodal therapy. A multidisciplinary team must develop an individualized treatment plan for each patient. Neurological and psychological aspects are essential components of this plan. The team must include experts in the treatment of headaches, fatigue, respiratory illnesses and other symptoms (shortness of breath, deconditioning, dizziness), as well as in occupational and physical therapy and clinical psychology.

Since the beginning of the pandemic, the team at the Kiel Pain Clinic has gained extensive experience in the diagnosis and treatment of long-term COVID-19 and has developed specialized therapy programs for this purpose. The focus is on headaches, other chronic pain, fatigue, memory problems, concentration difficulties, and other neurological and psychological symptoms.
Information on admission can be found here: https://schmerzklinik.de/service-fuer-patienten/