Table 2.

Summary of key findings on the associations of long COVID with reinfection, vaccination, and affected population.

	Key Findings Regarding Long COVID	Main Reference(s)
Reinfection	Reinfections increase the likelihood of long COVID (and additional complications, e.g., cardiac, pulmonary, neurological, in older subjects).	[55]
	The risk of developing long COVID symptoms is significantly lower after asymptomatic (compared to symptomatic) reinfection.	[56]
	Long COVID cases have been increasing upon reinfection with Omicron subvariants.	[57,58,60]
Vaccination	Vaccination against (severe) COVID-19 seems to also protect from long COVID (reduced risk by 15–41%).	[63,66,67]
	Two vaccine doses (of the primary scheme) are more effective than one dose.	[64,68,69,70]
	No difference in relation to the type of received vaccine.	[70]
Affected population	Children may also suffer from long COVID, but less frequently and less severely than adults.	[87,88,93]
	Chronic fatigue is one of the most common symptoms of long COVID present in up to 87% of children and adolescents with long COVID.	[90,91,97]
	Older age, comorbidities, and symptomatic infection are risk factors for long COVID in children.	[106]