Aim To describe epidemiological and clinical features of Croatian children and adolescents with a polymerase chain reaction (PCR)-confirmed coronavirus disease 2019 Methods Data on patients aged ≤19 years with a positive SARS-CoV-2 PCR test recorded in the period March 12-May 12 (first wave) and June 19-July 19, 2020 (second wave) were retrospectively analyzed The periods were separated by several weeks with no incident cases Results We analyzed data on 289 children and adolescents (6 5% of all cases;incidence rate [IR] = 3 54, 95% confidence interval [CI] 3 14-3 97/million person-days), 124 in the first wave (IR = 2 27) and 165 in the second wave (IR = 6 37): IRR second/first = 2 71 (2 13-3 44) During the first wave, the incidence was highest in infants (IR = 3 48), while during the second wave it progressively increased to IR = 7 37 in 15-19-year olds Family members were the key epidemiological contacts (72 6% cases), particularly during the first wave (95 8% vs 56 3%) Overall, 41 3% patients were asymptomatic, 25 3% in the first and 52 6% in the second wave Age 15-19 years (vs younger) was associated with a higher (RR = 1 26, 1 02-1 54) and infection in the second wave with a lower probability (RR = 0 66, 0 53-0 81) of being symptomatic The most common symptoms were fever, cough, and rhinorrhea In children aged ≥7 years, headache, anosmia/ageusia, and sore throat were also recorded Only one child suffered a severe disease All but 18 (7 8%) children were treated only symptomatically, and all fully recovered Conclusion A large proportion of SARS-CoV-2 PCR-positive children/adolescents were asymptomatic The associated disease was predominantly mild, comparably so in the first and second pandemic wave
Epidemiological and clinical features of Croatian children and adolescents with a PCR-confirmed coronavirus disease 2019: Differences between the first and second epidemic wave