Seroprevalence of SARS-CoV-2 infection in pediatric patients in a tertiary care hospital setting

• Published in: PloS one 2024-09, Vol.19 (9), p.e0310860
• Main Authors: Pattanakitsakul, Ploy, Pongpatipat, Chanya, Setthaudom, Chavachol, Kunakorn, Mongkol, Sahakijpicharn, Thiantip, Visudtibhan, Anannit, Apiwattanakul, Nopporn, Assawawiroonhakarn, Surapat, Pandee, Uthen, Techasaensiri, Chonnamet, Boonsathorn, Sophida, Chaisavaneeyakorn, Sujittra
• Format: Article
• Language: English
• Subjects: Adolescent; Antibodies; Antibodies, Viral - blood; Antibodies, Viral - immunology; Antigens; Asymptomatic; Bacterial pneumonia; Biology and life sciences; Care and treatment; Chemotherapy; Child; Child, Preschool; Children; China; Coronaviruses; COVID-19; COVID-19 - blood; COVID-19 - epidemiology; COVID-19 - immunology; COVID-19 diagnostic tests; COVID-19 vaccines; Cross-Sectional Studies; Disease transmission; Dosage and administration; Dyspnea; Enrollments; Epidemics; Female; Health aspects; Hospital patients; Hospitalization; Hospitals; Humans; Illnesses; Immunoglobulin G; Immunoglobulin G - blood; Immunoglobulins; Immunology; Infant; Infant, Newborn; Infections; Male; Medical research; Medicine and Health Sciences; Medicine, Experimental; Nucleocapsids; Oxygen saturation; Pandemics; Patients; Pediatrics; Pneumonia; Prospective Studies; Risk Factors; SARS-CoV-2 - immunology; SARS-CoV-2 - isolation & purification; Seroconversion; Seroepidemiologic Studies; Serology; Severe acute respiratory syndrome coronavirus 2; Signs and symptoms; Tertiary Care Centers; Thailand; Transplants & implants; Vaccination; Viral diseases
• ISSN: 1932-6203; 1932-6203
• DOI: 10.1371/journal.pone.0310860

Globally, cases of children's coronavirus disease 2019 (COVID-19) have been reported since the pandemic started. Most children have an asymptomatic or mild infection. Therefore, the incidence rate of COVID-19 in children might have been underestimated. This study aimed to determine (1) the seroprevalence (and seroconversion rates) of COVID-19, including associated risk factors, in pediatric patients visiting hospitals; and (2) the immunological responses to COVID-19. This was a prospective, cross-sectional study. Patients aged 0-18 years who visited the hospital from September 2020 to February 2022 were included. Demographic, clinical, and laboratory data were reviewed. A total of 1,443 pediatric patients were enrolled. Of these, 323 (22.6%) had a history of COVID-19. In the pre-Delta period, the seroprevalence increased from 4.1% to 70.6% in all included patients and from 0.5% to 10% in patients without a known history of COVID-19 compared with the Delta-Omicron period. The seroconversion rate was 6.8% (19 per 100 person-years) in pediatric patients with COVID-19. Risk factors for COVID-19 seropositivity were respiratory symptoms, being in an outpatient department setting, and infection during the Delta-Omicron period. Exposure to household members with confirmed COVID-19 was a risk factor for seropositivity and seroconversion. Infection during the Delta-Omicron period and testing conducted >2 weeks after the onset of symptoms was associated with spike immunoglobulin (Ig) M and spike and nucleocapsid IgG, respectively. High nucleocapsid IgG levels were associated with pneumonia in pediatric patients with COVID-19. Pediatric patients exposed to household members with COVID-19 and respiratory symptoms should be tested for COVID-19. Nucleocapsid IgG can be used as a surrogate marker to identify patients who may have experienced pneumonia from COVID-19 and as a screening tool for the COVID-19 outbreak, regardless of COVID-19 vaccination status.