BACKGROUND
An estimated 49 percent of people who become infected with COVID-19 will experience persistent symptoms after recovering from COVID-19, which is known as long COVID, post COVID, or “long-haul COVID.” These persistent symptoms can arise even after a person recovers from an asymptomatic or mild case of COVID-19. Long COVID is characterized by damage to several different vital organs, including the heart, kidneys, lungs, and brain. Some of this organ damage is caused by an overactive autoimmune response to COVID-19, in which the immune system produces autoantibodies that attack the body’s tissues and organs over time, including the joints, skin, and nervous system. This damage can lead to widespread and long-term inflammation. Being vaccinated against COVID-19 reduces the risk of developing long COVID after recovering from a breakthrough COVID-19 infection, but it is still possible to develop long COVID if you are vaccinated. The risk for developing long COVID is much higher for unvaccinated individuals; women are more likely to develop long COVID.
SYMPTOMS
Long COVID symptoms can include fatigue, impaired respiratory function, memory loss, “brain fog,” nausea, and difficulty concentrating. Some patients living with long COVID experience mild symptoms that clear up over the course of weeks or months while others experience severe, debilitating symptoms that do not improve over time or relapse after improving. One systematic study of long COVID patients found that over 85 percent experienced a relapse after symptoms initially improved. The U.S. Centers for Disease Control and Prevention (CDC) provides the following symptoms of long COVID:
- Difficulty breathing or shortness of breath
- Tiredness or fatigue
- Symptoms that get worse after physical or mental activities (post-exertional malaise)
- Difficulty thinking or concentrating (sometimes referred to as “brain fog”)
- Cough
- Chest or stomach pain
- Headache
- Fast-beating or pounding heart (heart palpitations)
- Joint or muscle pain
- Pins-and-needles feeling
- Diarrhea
- Sleep problems
- Fever
- Dizziness on standing (lightheadedness)
- Rash
- Mood changes
- Change in smell or taste
- Changes in menstrual period cycles
In addition to these symptoms, patients with long COVID are more likely to develop one or more Post-COVID Conditions following their recovery from COVID-19, which can further compromise their health. Review our Post-COVID Conditions page to learn more about the heightened health risks that patients are susceptible to following their recovery from COVID-19.
Some children develop multisystem inflammatory syndrome (MIS-C) after recovering from COVID-19, a condition characterized by widespread inflammation in the body. MIS-C is a different condition than long COVID, but symptoms of MIS-C can develop into long COVID symptoms over time.
DIAGNOSIS
Despite long COVID symptoms resulting from damage to their vital organs, receiving a diagnosis for long COVID can be challenging because the symptoms of the condition can manifest without being quantifiable in lab results or measurable in diagnostic imaging. There is currently no available diagnostic test to confirm that symptoms are wholly attributable to a prior COVID-19 infection. Definitions vary between practitioners, but generally patients who have a confirmed diagnosis of COVID-19 and who have experienced persistent symptoms for at least twelve weeks are considered to have long COVID. Refer to the table below to learn about the diagnostic tests that are commonly used to assess the presence and severity of long COVID symptoms.
|
Symptoms
|
Specialist
|
Diagnostic
|
|---|---|---|
|
Persistent cough |
Pulmonologist |
Chest X-ray or CT scan to check for lung damage or inflammation |
|
Shortness of breath |
Pulmonologist |
Pulmonary function test to measure how well the lungs are working |
|
Fatigue |
General practitioner or infectious disease specialist |
Blood work to check for inflammation or anemia |
|
Joint pain |
Rheumatologist |
X-rays or MRI to check for joint damage or inflammation |
|
Headache |
Neurologist |
MRI or CT scan to check for brain abnormalities or inflammation |
|
Loss of sense of smell or taste |
Otolaryngologist |
CT scan of the sinuses to check for damage or inflammation |
|
Difficulty with memory or concentration |
Neurologist |
Cognitive assessment or MRI to check for brain abnormalities or inflammation |
|
Heart palpitations or chest pain |
Cardiologist |
EKG or stress test to check for heart damage or abnormal function |
|
Anxiety or depression |
Psychiatrist |
Mental health evaluation to assess symptoms and determine appropriate treatment |
|
Persistent fever |
General practitioner or infectious disease specialist |
Blood work to check for ongoing infection or inflammation |
|
Persistent body aches or muscle pain |
General practitioner or infectious disease specialist |
Blood work to check for inflammation |
|
Persistent diarrhea or abdominal pain |
Gastroenterologist |
Stool sample or colonoscopy to check for gastrointestinal issues |
|
Persistent dizziness or lightheadedness |
Cardiologist or neurologist |
EKG or MRI to check for heart or brain abnormalities |
|
Persistent skin rash or changes in skin color |
Dermatologist |
Skin biopsy to check for inflammation or other abnormalities |
|
Persistent eye issues, such as redness, swelling, or vision changes |
Ophthalmologist |
Eye exam and possibly imaging tests to check for eye abnormalities or inflammation |
Researchers have not yet identified a reliable biomarker for diagnosing long COVID. However, researchers studying long COVID patients have found several blood biomarkers that may act as indicators or therapeutic targets for long COVID. The table below lists these biomarkers and links to blood tests that can be used to measure them.
|
Target
|
Test
|
Link
|
|---|---|---|
|
1-Methylnicotinamide |
Vitamin B3 (Niacin and Metabolite) |
|
|
Adenosine Deaminase (ADA) |
Severe Combined Immunodeficiency (SCID): ADA (Full Gene Sequencing) |
|
|
Alanine Aminotransferase (ALT) |
Hepatic Function Panel |
|
|
Albumin |
Long COVID Profile |
|
|
Aspartate Aminotransferase (AST) |
Hepatic Function Panel |
|
|
Complement 5b-9 (C5b-9) |
Complement C3a |
|
|
C-Reactive Protein (CRP) |
Long COVID Profile |
|
|
Cystatin C |
Cystatin C |
|
|
D-Dimer |
D-Dimer |
|
|
Erythrocyte Sedimentation Rate (ESR) |
Sedimentation Rate, Modified Westergren |
|
|
Factor VIII |
Factor VIII Inhibitor Profile, Comprehensive |
|
|
Ferritin |
Long COVID Profile |
|
|
Fibrinogen |
Fibrinogen Evaluation Profile |
|
|
Glial Fibrillary Acidic Protein (pGFAP) |
Glial Fibrillary Acid Protein (GFAP), Plasma |
|
|
Glutamine/Glutamate Ratio |
Amino Acid Profile, Quantitative, Plasma |
|
|
Hemoglobin |
Long COVID Profile |
|
|
Highly Sensitive Troponin T (Hs TnT) |
Troponin T (Highly Sensitive) |
|
|
Indole-3-lactic Acid |
Lactic Acid, Plasma |
|
|
Interleukin-10 (IL-10) |
Interleukin-10, Serum |
|
|
Interleukin-2 (IL-2) |
Interleukin-2, Serum |
|
|
Interleukin-4 (IL-4) |
Interleukin-4, Serum |
|
|
Interleukin-6 (IL-6) |
Interleukin-6, Serum |
|
|
Lactate Dehydrogenase (LDH) |
Lactic Acid Dehydrogenase |
|
|
L-Cystein |
Amino Acid Profile, Quantitative, Plasma |
|
|
L-Glutamine |
Amino Acid Profile, Quantitative, Plasma |
|
|
L-Methionine |
Amino Acid Profile, Quantitative, Plasma |
|
|
Matrix Metalloproteinase-1 (MMP-1) |
Vectra |
|
|
Matrix Metalloproteinase-9 (MMP-9) |
MMP-9 (Matrix Metalloproteinase-9) |
|
|
Myeloperoxidase (MPO) |
Myeloperoxidase (MPO) |
|
|
Neurofilament Light Chain (NFL) |
Neurofilament Light Chain, Plasma |
|
|
N-terminal B-type Natriuretic Peptide (NT-BNP) |
B-Type Natriuretic Peptide (BNP) |
|
|
N-terminal Pro B-type Natriuretic Peptide (NT-proBNP) |
NT-proBNP |
|
|
Ornithine |
Amino Acid Profile, Quantitative, Plasma |
|
|
Pipecolic Acid |
Pipecolic Acid, Serum |
|
|
Quinolinic Acid |
Organic Acid Analysis, Urine |
|
|
Sarcosine |
Amino Acid Profile, Quantitative, Plasma |
|
|
SARS-CoV-2 Antibodies |
SARS-CoV-2 Antibody Profile, Nucleocapsid and Spike |
|
|
ß-Glucan |
1,3-ß-D-Glucan Assay |
|
|
S-Sulfocysteine |
S-Sulfocysteine Panel, Urine |
|
|
Taurine |
Amino Acid Profile, Quantitative, Plasma |
|
|
Tryptase |
Tryptase |
|
|
Tumor Necrosis Factor-α (TNF-α) |
Tumor Necrosis Factor-α |
|
|
Urokinase Type Plasminogen Activator (uPA) |
Plasminogen Activity |
|
|
Vascular Adhesion Molecule-1 (sVCAM-1) |
Vectra |
|
|
Vascular Endothelial Growth Factor (VEGF) |
Vascular Endothelial Growth Factor |
|
|
von Willebrand Factor Antigen (VWF:Ag) |
von Willebrand Factor (vWF) Antigen |
TREATMENT
There are currently no available treatments for long COVID, but many patients report that their symptoms improve over time. However, supportive care can help alleviate some symptoms of long COVID. Patients seeking treatment for long COVID may be referred to specialists, such as neurologists, cardiologists, pulmonologists, and psychologists who can provide treatments to relieve some long COVID symptoms. Counseling may also be offered to provide mental health support.
LONG COVID AND DISABILITY
Long COVID is recognized under federal law as a disability, which protects people with long COVID from discrimination on the basis of their disability. Protection from discrimination in this context means that people are entitled to “full and equal opportunities to participate in and enjoy all aspects of civic and commercial life.” To qualify for these protections, a person’s long COVID symptoms must represent a physical or mental impairment that substantially limits one or more major life activities. A person with long COVID who has a record of such an impairment or is regarded as having such an impairment may also be similarly protected, depending on their individual circumstances. The following examples are situations where a person’s long COVID symptoms satisfy the requirement of substantially limiting one or more major life activities:
- A person with long COVID who has lung damage that causes shortness of breath, fatigue, and related effects is substantially limited in respiratory function, among other major life activities.
- A person with long COVID who has symptoms of intestinal pain, vomiting, and nausea that have lingered for months is substantially limited in gastrointestinal function, among other major life activities.
- A person with long COVID who experiences memory lapses and “brain fog” is substantially limited in brain function, concentrating, and/or thinking.
Please note that these examples are not an exhaustive list. Having long COVID does not always qualify as a disability. Depending on the extent of a person’s physical or mental impairment, they may qualify for disability benefits, such as short-term disability insurance, long-term disability insurance, and Social Security Disability Insurance (SSDI), among others. Review our COVID-19 and Disability Benefits page to learn more.
