Children infected with the SARS-CoV-2 virus, but not hospitalised, can still experience long COVID symptoms up to three months past infection, according to a study.

The research, published in The Pediatric Infectious Disease Journal, examined data from volunteers between the ages of 5 and 18 across the state of Texas, US.

The volunteers were enrolled in the Texas CARES survey, which began in October of 2020 with the goal of assessing COVID-19 antibody status over time among a population of adults and children in Texas.

Data for this study was collected before and after the vaccine rollout and during the waves of the Delta and Omicron variants.

“We were interested in understanding if children impacted with an acute or severe infection of COVID-19 would go on to have persisting symptoms, or what we call long COVID,” said Sarah Messiah, first author of the study and professor at the University of Texas Health Science Center.

“This particular study is unique as the first population-based study in literature to report on prevalence of long COVID in children who have not been hospitalised with COVID-19,” Messiah said.

A total of 82 pediatric volunteers (4.8 per cent of the total 1,813) reported having long COVID symptoms, the researchers said.

About 1.5 per cent showed symptoms that lasted between four and 12 weeks, including loss of taste and smell, fatigue, and cough, they said.

The study also found that an additional 3.3 per cent children reported that symptoms such as loss of taste and smell, cough, and difficulty breathing persisted for longer than 12 weeks.

“When we looked at risk factors of those who reported symptoms past 12 weeks, we found that children who were unvaccinated and who had obesity had a higher chance of developing long COVID,” Messiah said.

“These findings are consistent with other literature that found children and adults who have comorbid health conditions and are unvaccinated are at a higher risk of being hospitalised for the virus,” the scientist said.

The researchers also found that children infected with COVID-19 before the emergence of the Delta variant were more at risk of developing long COVID.

“If you had COVID-19 earlier in the pandemic, you were more at risk for longer symptoms.

“With Delta and Omicron, we did see a lot of children who ended up hospitalised, but their symptoms were less severe, and our results show they were also less likely to report persistent symptoms too,” Messiah said.

The finding is important because it highlights the presence of non-hospitalised youth who may also experience persistent long COVID symptoms after infection, the researchers said.

“There may be a perception that one needs to be hospitalised to have long COVID, and that is not what we found,” Messiah said.

“I encourage parents to still take caution and get their child vaccinated against COVID-19, because we now know that it will decrease the risk of infection and long COVID,” she added.