Most young people who had persistent symptoms of COVID-19 after a positive test no longer had symptoms after two years.

This is according to a new study that aims to estimate the number of teenagers still suffering from fatigue and other problems months and years after their initial infections.

Researchers asked more than 12,600 teenagers in England aged 11 to 17 about their COVID-19 symptoms three, six, 12, and 24 months after they tested positive between September 2020 and March 2021.

The researchers defined long COVID, or “post-COVID-19 condition,” as having one persistent symptom such as fatigue, shortness of breath, trouble sleeping, or headaches as well as one problem related to mobility, self-care, carrying out their usual activities, pain, or feeling worried or sad.

Nearly 1,000 teens tested positive and provided symptom updates at all four time points.

Three months after the positive test, around a quarter of those teens fit the researchers’ definition of long COVID. 

A year later, one in 10 fit the definition, and two years after the initial positive test, around 7 per cent fit the definition.

In total, 68 young people continued to have COVID-19 symptoms two years after their positive test. This group consistently had five or six symptoms two years on, the researchers said.

The most common symptoms were tiredness, trouble sleeping, shortness of breath, and headache.

The findings were published in the journal Nature Communications Medicine on Wednesday and were part of a study funded by the UK’s National Institute for Health and Care Research (NIHR).

“Unfortunately, these results recapitulate findings in the adult population – emphasising the persistent nature of Long COVID in some individuals,” Ziyad Al-Aly, chief of research and development at the VA St Louis Health Care System in the US, told Euronews Heath in an email. He was not involved in the study.

It was estimated in June last year that 36 million people living in Europe and some parts of central Asia – or one in 30 – may have experienced long COVID in the three years since the beginning of the pandemic.

‘Need to address underlying causes of ill health’

There were a few limitations to the new study, notably that the symptoms were self-reported and that the original PCR test results were from an earlier wave of COVID-19 before the Delta and Omicron variants became dominant.

Females were nearly twice as likely to have long COVID after two years compared to males, the researchers found. 

Older teenagers and those who were the most deprived were also less likely to have recovered.

“Our findings show that for teenagers who fulfilled our research definition of long COVID three months after a positive test for the COVID virus, the majority have recovered after two years,” Sir Terence Stephenson, the study’s chief investigator, first author, and a professor at University College London, said in a statement.

“This is good news but we intend to do further research to try to better understand why 68 teenagers had not recovered,” he added.

Other researchers who commented on the study said it was in line with findings in the adult population and added to scientists’ understanding of the condition.

“This study again shows that health conditions like long COVID tend to affect the most disadvantaged in society, both young and old,” said Dr Nathan Cheetham, a senior postdoctoral data scientist at King’s College London.

Cheetham, who was not involved in the study, said in a statement that the survey reinforces “the need to address the underlying causes of ill health,” such as poor housing and unequal healthcare access.

“More needs to be done to help us understand how to best prevent and treat Long COVID – especially in children and young adults,” Al-Aly, who studies the condition, added in an email.

“We also need research to characterise the impacts of long COVID on children’s development, educational attainment and longer-term impacts”.

“The totality of evidence consistently shows that while some people (children, young persons, adults, and older adults) recover, many experience persistent symptoms for years after the initial infection,” he said, adding the study was important as long COVID “has been less well studied in children and young adults”.