The COVID-19 pandemic that first started in December 2019 is ongoing and has already infected more than 180 million persons resulting in 4 million deaths by the end of June 2021. We have learnt much about the virus, the disease that it causes,
the clinical management and prevention methods including non-pharmaceutical interventions and vaccination. However, we are only just beginning to learn about the later consequences of COVID infection, the “post-COVID condition” and often termed as “long COVID”.
Long COVID is the umbrella term for a wide range of physical and mental consequences experienced by some patients after infection by the virus, SARS-Cov2. For the purposes of this article, it relates to the condition that is present at least 4 weeks after the SARS CoV2 infection. The frequency varies considerably in the medical literature and ranges from 5% to 80%. It may also affect persons who had asymptomatic or mildly symptomatic SARS CoV2 infection.
The long COVID symptoms may last weeks to months and may be:
1. Continuing or persistent symptoms that started from the onset of the infection
2. Recurrent symptoms which wax and wane in severity
3. New symptoms which were not present during the acute illness
Multiple onset patterns have been described and some of them share similarities with other post-viral syndromes, post-severe pneumonia (from whatever aetiology), chronic fatigue syndrome, dysautonomia, orthostatic intolerance like POTS, mast cell activation syndrome etc.
Long COVID is a heterogenous condition that we are just beginning to learn about and it is likely the symptoms are due to different underlying disease mechanisms including:
1. Organ damage from acute infection
2. Complications from persistent hyperinflammatory state
3. Ongoing viral activity from the host reservoir
4. Inadequate antibody response to SARS CoV2
The organ systems and conditions affected may be broadly described as follows:
|Cardiovascular||Myocarditis, pericarditis, hypertension, heart failure, orthostatic intolerance|
|Pulmonary||Interstitial lung disease, reactive airway disease, bronchiectasis|
|Neurologic||Stroke, olfactory and gustatory disturbances, sleep dysregulation, cognitive decline, memory impairment, headache, weakness, neuropathy|
|Renal||Chronic kidney disease|
|Hematologic||Venous thromboembolism, arterial thrombosis|
|Psychiatric||Depression, anxiety, post traumatic stress disorder, psychosis|
|Urologic||Sexual dysfunction, incontinence|
|Others||Fatigue, dysautonomia, hearing loss, pain syndromes, reactivation of other viral infections, mast cell activation syndrome|
Common symptoms of Long COVID/Post-COVID:
|Increased respiratory effort, dyspnoea||Diarrhoea|
|Post-exertional malaise||Insomnia and sleep disturbances|
|Cough||Fever- usually low grade and intermittent|
|Fatigue low energy||Impaired daily function/mobility|
|Palpitations and/or tachycardia||Chronic pain|
|Brain fog, cognitive impairment||Rash|
|Myalgia||Anosmia or dysgeusia|
|Paraesthesia||Menstrual cycle irregularities|
Approach to Management
There are considerable challenges estimating the exact prevalence of long COVID as this syndrome encompasses a wide spectrum of physical, social, psychological consequences with functional limitations. It is important to highlight that we are just starting the understand this condition and that there are no tests that specifically diagnose “Long COVID”.
Firstly, assessment must actively exclude an urgent clinical condition such as pulmonary embolism, acute myocardial infarction / myocarditis, stroke, renal failure etc.
For patients presenting with symptoms lasting between 4 to 12 weeks post-infection, the management may be expectant and mainly prescribing symptomatic treatment. Setting health goals to optimize function and managing expectations are important. Having patient diaries and calenders to chart progress are often a good start.
Baseline blood tests and radiological imaging, where appropriate, for the lungs and brain to exclude other underlying conditions may be indicated.
At the present time, there are no definitive treatment of “Long COVID” other than supportive therapy. There are some suggestion that vaccination may ameliorate some of the symptoms. Patients who have recovered from COVID19 Infection are encouraged to take COVID 19 vaccinations 3-6 months post-recovery.
While we have made considerable progress in fighting the pandemic, it is also clear that we are likely to be years away from eradicating this infection and may never do so. The long term consequences of COVID19 need to be defined, studied and effective management strategies devised.