Long COVID: Why do some people's COVID-19 symptoms last months?

Most people who get COVID-19 recover in two to three weeks. However, some people - even if they only had a mild case of COVID-19 - keep having symptoms months after they first get the disease. This is called 'long COVID' and it can be exhausting for 'COVID long haulers'.

Doctors and scientists are still learning about COVID-19 and how to treat it, but it's becoming clear that the disease affects us both in the short and the long term. According to the World Health Organization, there's growing evidence that COVID-19 can damage organs and increase blood clotting and inflammation. "This can affect many different body systems, in particular the heart, lungs and brain."

What is long COVID?

Long COVID is more common than you might think. About 1 in every 10 people who get COVID-19 still feels ill more than three weeks after they first become ill with the disease.

The World Health Organization acknowledges the effects of having long COVID, developing new medical conditions after having had COVID-19, and living with the health results of having had COVID-19. Long COVID can be severely disabling. People with long COVID say that they now struggle to perform everyday tasks.

While there isn't an easy way to diagnose long COVID, many people who have it are constantly exhausted (have severe fatigue) and a range of troubling physical symptoms that make it difficult for those who are employed to return to work.

Can you catch COVID-19 from someone with long COVID?

The short answer is probably not.

"People who get COVID-19 seem to be most infectious to others within the first five days but not afterwards," says Dr Noluthando Nematswerani, Discovery Health's Head of the Centre for Clinical Excellence. She explains that unless someone gets infected with COVID-19 again, it's unlikely that having long COVID symptoms means they can spread COVID-19.

In January 2021, the Cleveland Clinic said that tests don't detect the virus that causes COVID-19 in most people who still have symptoms 28 days or later after they were first infected.

What are the symptoms of long COVID?

Feeling weak and fatigued (extremely tired) all the time are typical of long COVID. But COVID long haulers have a range of symptoms all at the same time.

The World Health Organization and the United States Centers for Disease Control and Prevention (CDC) divide long-COVID symptoms into three groups: common symptoms, less common but more serious symptoms, and serious long-term complications.

The most common symptoms include:

Fatigue
Shortness of breath
Cough
Joint pain
Chest pain

Less common but more serious symptoms include:

Severe fatigue
Brain fog (difficulty thinking and concentrating)
Headaches
Muscle pain
Fever that comes and goes
Depression
Heart palpitations (feeling that your heart is beating fast)

Serious long-term complications COVID include:

Brain disorders: smell and taste problems, sleep issues, difficulty with concentration, memory problems
Heart and vein disorders: inflammation of the heart muscle and increased risk of damage to the heart, lungs and brain
Lung function abnormalities
Serious kidney injury
Skin changes: rash and hair loss
Psychiatric symptoms: depression, anxiety and changes in mood

What is it like to have long COVID?

It's clear that lasting COVID-19 changes how well a person can carry out their duties, work, and enjoy a good quality of life. "Long COVID affects every aspect of life. It affects one's mental health and one's ability to focus and work, and could have economic consequences too. This is why it's so important that we acknowledge the prevalence and growing awareness around long COVID," adds Dr Nematswerani

Research published in BMC Health Services Research in December 2020 includes details from interviews with people who have long COVID. The people they interviewed said that they were trapped in a cycle where they slowly got better only to suddenly get worse again. This is stressful and it they didn't know if they would ever be completely healthy again.

One participant, an office worker, explained the effects of the brain fog they felt:

"I'm not working, I haven't... I wasn't able to go back to work and then I got made redundant. I'm... I can't even imagine how I'm going to find a new job yet. In the last week, I'm wondering because my brain fog seems to have lifted and it's feeling possible finally, after nearly six months, that I might one day find a new job. But my life is just nothing like it was and it's not really the life I want, you know. I need to improve."

Others spoke about the long-term fatigue they experienced and the dramatic impact on their ability to carry out basic daily activities:

"My energy levels are returning - that took me weeks and weeks. I mean, this morning I went for a two-hour walk and actually when I got back, I slept for two and a half hours."
"And the fatigue is literally like hitting a wall. I can't stay awake anymore. It's just like, wow, I have to go to bed."

How should long COVID be managed?

The best person to manage long COVID is your GP. They can refer you to a specialist if necessary and make sure the care you get meets your needs. Once a person recovers from COVID-19, you and your doctor should monitor your health in the months and years afterwards. "This is because there are potential long-term consequences that we have not yet determined," says Dr Nematswerani.

If a person has had COVID-19, they should also check in with their doctor if they have any worrying symptoms. They could be the sign of a deeper medical problem.

Is it safe for people with long COVID to get a COVID-19 vaccine while they still have symptoms?

Yes. According to the CDC (Centers for Disease Control and Prevention), if a test shows you have COVID-19 (or you think you have it), you should wait 10 days (or until you are no longer showing symptoms of COVID-19) to receive the vaccine. However, if people have the lasting symptoms typical of long COVID, they should be vaccinated against COVID-19.