Long Covid An Overview

03 May

Long Covid An Overview

An evolving problem with an extensive impact

We just over one year on since the COVID-19 pandemic has started and you may have heard or read the name ‘Long Covid’ or ‘Post-COVID-19 syndrome’ in the news. In this short article we would like to explain the symptom picture (i.e. condition) these terms refer to.

Long Covid is a term that describes the effects of Covid-19 disease that continue for months beyond the active infection. This infection usually starts in the lungs but the virus can find its way into any and every organ and tissue, as post-mortem studies have shown. As a result, it can affect many organs (even simultaneously), including the blood vessels, heart, brain, digestive system and skin, and can lead to serious conditions such as chronic fatigue, chronic pain and depression. 

It is acknowledged that there are still many uncertainties concerning the long-term effects of COVID-19 but there is a UK-wide guideline that is being developed by the National Institute for Health and Care Excellence (NICE), the Scottish Intercollegiate Guidelines Network (SIGN) and The Royal College of General Practitioners (RCGP) on request from the NHS England and the Chief Medical Officer of the Scottish Government. This guideline is still ‘being developed’ because it is necessary to use a ‘living approach’, where everything is continuously reviewed and updated based on the developing and emerging evidence base. 

There may be over a million Long Covid sufferers in the UK by now, and therefore it is important to understand the potential medical, psychological, and rehabilitation needs for this patient group to support their recovery.

Long Covid is not contagious. Symptoms of Long Covid are caused by your body's response to the virus continuing beyond the initial illness. It has been found that women are affected more than men, in a 5:1 ratio.

Current case definitions

Below are some current case definitions developed by medical consensus:

Acute COVID -19 infection
Signs and symptoms of acute COVID-19 infection that may last up to 4 weeks. 

Ongoing symptomatic COVID-19
Signs and symptoms of COVID-19 infection from 4 weeks up to 12 weeks.  

Post-COVID-19 syndrome or ‘Long Covid’
Signs and symptoms developed during or following COVID-19 infection that continue for more than 12 weeks after the acute phase of COVID-19 ended, and are not explained by an alternative diagnosis. Currently, there are over 200 symptoms associated with Long Covid, and it is common to have 1 or more ongoing symptoms, which can affect any system in the body.

Diagnosis of COVID-19: A person may be diagnosed with COVID-19 based on clinical symptoms WITH OR WITHOUT a positive SARS-CoV-2 test (PCR, antigen or antibody), and this diagnosis can be made retrospectively based on symptoms alone (for those who self-managed their acute illness).

Findings of the largest known study to date of patients with symptoms of ‘Long Covid’

The largest known report to date of patients with symptoms consistent with ‘Long COVID’ examined 3,762 respondents from 56 countries (age range: age 18-39 31.5%, age 40-49 31%, and age 50+ 37.7%). 2,330 were tested for SARS-CoV-2 but only 1,020 had tested positive (RT-PCR, antigen, or antibody test). 92% of the respondents were not hospitalized. (Davis et. al., 2020. Characterizing Long COVID in an International Cohort: 7 Months of Symptoms and Their Impact)

Researchers found that the symptom picture was similar between those who had been tested positive for SARS-CoV-2 test and those who had not. They also found that 10 organ systems were affected over a 7 months period. 

The most prevalent and persistent symptoms by week 28 were:

  • fatigue (80% of respondents)
  • brain fog/memory issues and neurological problems (60%)
  • headaches, insomnia, shortness of breath and palpitations ( near 40%)

The top three most debilitating symptoms were: 

  • fatigue
  • breathing issues
  • cognitive dysfunction

The worst symptoms with the most improvement were reported to be:

  • fatigue
  • breathlessness
  • headaches
  • palpitations
  • brain fog 

It was reported that with time people learned to manage their symptoms better, and most of them felt notable rates of improvement in symptoms after 6 months and 10 months. 

Interestingly, the researchers found no difference in symptoms in different age groups. 

In fact, younger cohorts were affected more severely in the following categories:

  • attention
  • thinking
  • executive function
  • problem-solving
  • confusion

Other notable and concerning findings: 

  • 73% of responders were not able to work in the same way as pre-Covid
  • 93% were unable to work full time without risking their well-being or relapse
  • After 6 months, most patients still had most symptoms, however, some improvement was noticed

This is a great and insightful study that helps us understand how the symptoms of  ‘Long Covid’ may affect people. However, there are some limitations of this study, which are important to mention and these include:

  • data were based on self-reported symptoms and COVID-19 testing results
  • participants self-selected into the study, which limits generalisability
  • responders were primarily white and female, which is not representative of the larger population
  • most participants did not receive a positive RT-PCR, antigen, or antibody test for COVID-19, so other conditions may have contributed to the symptoms experienced

As mentioned above, this virus (SARS-CoV-2) can find its way into any and every organ and tissue in the body, and hence can affect multiple systems, including the cardiovascular system, digestive system, skin and brain. Currently, there are over 200 symptoms associated with Long covid, of which the topmost reported symptoms are:

  • fatigue
  • poor exercise tolerance/post-exertional malaise
  • cognitive dysfunction, brain fog  (not being able to think straight or focus) 
  • shortness of breath
  • tightness of chest
  • headaches
  • IBS symptoms (diarrhea)
  • insomnia
  • anxiety and depression
  • palpitations
  • joint or muscle pain
  • heart palpitations
  • dry cough

When managing patients with symptoms of ‘Long Covid’, it is important to ask about the right symptoms because practitioners often miss questions related to neurological, especially cognitive function, post-exertional malaise and questions on relapses. This may particularly be true when using algorithms, which will be biased without a representative patient and symptom dataset.


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