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Long-Term Persistence of Anti-SARS-CoV-2 Antibodies in a Pediatric Population
Ana Méndez-Echevarría1, Talía Sainz1, Iker Falces-Romero2
1Pediatrics and Infectious Disease Unit, La Paz University Hospital, Translational Research Network of Pediatric Infectious Diseases (RITIP), 28049 Madrid, Spain.
Insights
Most children infected with SARS-CoV-2 maintain positive IgG antibodies six months post-infection. Antibody loss was more common in asymptomatic or mildly symptomatic children with initially low antibody titers.
Area of Science:
- Pediatric Infectious Diseases
- Immunology
- Virology
Background:
- Antibody dynamics following SARS-CoV-2 infection in children remain poorly understood.
- Limited data exists on long-term antibody responses in pediatric populations.
Purpose of the Study:
- To investigate the persistence of SARS-CoV-2 specific IgG antibodies in children up to six months post-infection.
- To identify factors associated with antibody loss in pediatric COVID-19 cases.
Main Methods:
- A prospective cohort study involving 58 children infected with SARS-CoV-2 between March and May 2020.
- Children were categorized into hospitalized COVID-19, mild outpatient COVID-19, and asymptomatic seropositive contacts.
- Serological testing for IgG antibodies was performed at baseline and six months post-infection.
Main Results:
- 86% of children maintained positive IgG antibodies six months after infection.
- Higher initial IgG titers and diagnoses of lower respiratory tract infection or multisystemic inflammatory syndrome were associated with sustained antibody response.
- Children of healthcare workers in the seroprevalence study lost antibodies more frequently.
Conclusions:
- The majority of children infected with SARS-CoV-2 exhibit sustained IgG antibody responses six months post-infection.
- Antibody loss is more likely in children with asymptomatic or mild infections and lower initial antibody titers.
Background:
Antibody dynamics over time after SARS-CoV-2 infection are still unclear, and data regarding children are scarce.
Methods:
A prospective cohort study was performed including children infected by SARS-CoV-2 between March and May 2020. Patients were categorized into 3 groups: children admitted with COVID-19; outpatient children with mild COVID-19; and seropositive children participating in a seroprevalence study among cohabitants of infected healthcare workers (HCWs). Six months after the infection, a new serological control was performed.
Results:
A total of 58 children were included, 50% male (median age 8.3 [IQR 2.8-13.5] years). The median time between the two serological studies was 186 (IQR 176-192) days, and 86% (48/56) of the children maintained positive IgG six months after the infection. This percentage was 100% in admitted patients and 78% among the rest of the included children (p = 0.022). The diagnoses of lower respiratory tract infection and multisystemic inflammatory syndrome were associated with persistence of IgG (p = 0.035). The children of HCWs in the seroprevalence study lost antibodies more often (p = 0.017). Initial IgG titers of the children who remained positive six months after the infection were significantly higher (p = 0.008).
Conclusions:
Most children infected by SARS-CoV-2 maintain a positive serological response six months after the infection. Those children who lost their IgG titer were more frequently asymptomatic or mildly symptomatic, presenting with low antibody titers after the infection.
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