Long COVID is real

Three years of research have shown that COVID-19 vaccination reduces long COVID risk.

by Aisha Abdullah June 7, 2024June 7, 2024

A person with short black hair removing their glasses and pinching the bridge of their nose.

Illustration: PGN

Long COVID is a real condition, affecting approximately 17 million people in the U.S. alone. Although the cause of long COVID is still being investigated, we know that the condition is triggered by COVID-19 infections.

However, some vaccine skeptics have floated the myth that long COVID is a side effect of COVID-19 vaccination. They call the alleged phenomenon “long vax.”

Here’s how we know that long COVID is not linked to vaccination.

What is long COVID?

In spring 2020, months after the virus that causes COVID-19 was discovered in Wuhan, China, reports began to emerge about some COVID-19 patients experiencing symptoms weeks and months after their infection resolved. These were the earliest reports of what would come to be known as long COVID.

Long COVID comprises a collection of symptoms experienced for at least four weeks after a COVID-19 infection and extend to months or even years after. Symptoms may be mild to severe and may include fatigue, brain fog, chronic headaches, insomnia, loss of taste and smell, joint pain, gastrointestinal distress, and mental health issues.

Around 10 percent of U.S. adults who have had COVID-19 reported having long COVID as of spring 2024, and 30 percent reported having had it at some point. Most evidence suggests long COVID rates in the U.S. of 5 to 10 percent.

How do we know that vaccines don’t cause long COVID?

Researchers are still investigating what causes long COVID. There’s evidence of several factors playing a role, including bits of the virus remaining active in the body, an abnormal or overactive immune response to infection, and viral damage to tissues and blood vessels causing lasting symptoms.

Researchers know that vaccines do not cause long COVID. Reports of long COVID predate the COVID-19 vaccine rollout by nearly a year. Long COVID cases in the first year of the pandemic could hardly have been caused by vaccines that either didn’t exist or were not yet widely available to the public.

Research over the last three years shows that unvaccinated people are twice as likely to develop long COVID as vaccinated people. Moreover, COVID-19 vaccination significantly reduces the risk of long COVID.

How are extremely rare, post-COVID-19 vaccination symptoms distinct from long COVID?

Like any medicine or treatment, vaccines can in very rare instances cause serious side effects. Fortunately, COVID-19 vaccines have been shown to be incredibly safe, and lasting side effects are exceptionally uncommon. They are so rare that research into post-COVID-19 vaccination symptoms is limited.

The largest studies to date are small observational studies that have not yet undergone peer review. One of the studies is part of Yale’s LISTEN study, which investigates how the immune response may be involved in both long COVID and post-vaccination symptoms.

However, there is currently no evidence that the symptoms reported in these studies were necessarily caused by the vaccines. Further research is needed to better understand post-vaccination syndrome.

Why do skeptics mischaracterize long COVID?

Long COVID is difficult for vaccine opponents to contend with because there is indisputable evidence that COVID-19, even in its mildest form, is a real threat. More importantly, the risk of long COVID is a compelling reason to get vaccinated.

The “long vax” narrative discredits what we know about long COVID by falsely reframing it as a vaccine side effect. However, these claims have no basis in reality.

For four years, scientific studies have found that COVID-19 vaccination significantly reduces long COVID risk. Meanwhile, no studies have found any link between COVID-19 vaccines and long COVID.