{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,30]],"date-time":"2026-09-30T05:43:58Z","timestamp":1790747038437,"version":"4.1.0"},"reference-count":35,"publisher":"Frontiers Media SA","license":[{"start":{"date-parts":[[2021,10,8]],"date-time":"2021-10-08T00:00:00Z","timestamp":1633651200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/100012940","name":"Universit\u00e4tsklinikum T\u00fcbingen","doi-asserted-by":"publisher","award":["none"],"award-info":[{"award-number":["none"]}],"id":[{"id":"10.13039\/100012940","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":["frontiersin.org"],"crossmark-restriction":true},"short-container-title":["Front. Immunol."],"abstract":"<jats:p>Saliva is a body fluid with hitherto unused potential for the assessment of SARS-CoV-2 antibodies. Specific antibodies can indicate a past SARS-CoV-2 infection and allow to estimate the proportion of individuals with a potential protective immunity. First, we carefully characterized plasma samples obtained from adult control groups with and without prior SARS-CoV-2 infection using certified reference ELISAs. Simultaneously collected saliva samples of confirmed convalescent and negative individuals where then used to validate the herein newly developed ELISA for the detection of SARS-CoV-2 IgG antibodies in saliva. The saliva ELISA was applied to assess SARS-CoV-2 exposure in young children (N = 837) in the age between 1 and 10 years in T\u00fcbingen, Germany, towards the end of the first pandemic year 2020. Sensitivity and specificity of the new saliva ELISA was 87% and 100%, respectively. With 12% of all T\u00fcbingen children sampled <jats:italic>via<\/jats:italic> their respective educational institutions, estimates of SARS-CoV-2 antibody prevalence was 1.6%. Interestingly, only 0.4% preschool kids were positive compared to 3.0% of primary school children. Less than 20% of positive children self-reported symptoms within two months prior to saliva sampling that could be associated - but not exclusively - with a SARS-CoV-2 infection. The saliva ELISA is a valid and suitable protocol to enable population-based surveys for SARS-CoV-2 antibodies. Using non-invasive sampling and saliva ELISA testing, we found that prevalence of SARS-CoV-2 antibodies was significantly lower in young children than in primary school children.<\/jats:p>","DOI":"10.3389\/fimmu.2021.753435","type":"journal-article","created":{"date-parts":[[2021,10,10]],"date-time":"2021-10-10T19:43:21Z","timestamp":1633895001000},"update-policy":"https:\/\/doi.org\/10.3389\/crossmark-policy","source":"Crossref","is-referenced-by-count":15,"title":["Non-Invasive Antibody Assessment in Saliva to Determine SARS-CoV-2 Exposure in Young Children"],"prefix":"10.3389","volume":"12","author":[{"given":"Constanze","family":"Heinzel","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yudi T.","family":"Pinilla","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"K\u00e4the","family":"Elsner","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Evelyn","family":"Friessinger","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Benjamin","family":"Mordm\u00fcller","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Peter G.","family":"Kremsner","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jana","family":"Held","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Rolf","family":"Fendel","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Andrea","family":"Kreidenweiss","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1965","published-online":{"date-parts":[[2021,10,8]]},"reference":[{"key":"B1","doi-asserted-by":"publisher","DOI":"10.1001\/jamapediatrics.2020.1467","article-title":"Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) Infection in Children and Adolescents: A Systematic Review","volume":"174","author":"Castagnoli","year":"2020","journal-title":"JAMA Pediatr"},{"key":"B2","doi-asserted-by":"publisher","DOI":"10.1093\/cid\/ciaa1912","article-title":"Longitudinal Testing for Respiratory and Gastrointestinal Shedding of SARS-CoV-2 in Day Care Centres in Hesse, Germany","author":"Hoehl","year":"2021","journal-title":"Clin Infect Dis"},{"key":"B3","doi-asserted-by":"publisher","DOI":"10.1001\/jamapediatrics.2021.0001","article-title":"Prevalence of SARS-CoV-2 Infection in Children and Their Parents in Southwest Germany","volume":"175","author":"T\u00f6nshoff","year":"2021","journal-title":"JAMA Pediatr"},{"key":"B4","doi-asserted-by":"publisher","first-page":"1664","DOI":"10.15585\/mmwr.mm695152a8","article-title":"COVID-19 Stats: COVID-19 Incidence,* by Age Group","volume":"69","year":"2021","journal-title":"MMWR Morb Mortal Wkly Rep"},{"key":"B5","doi-asserted-by":"publisher","DOI":"10.7189\/jogh.10.021101","article-title":"The Role of Children in the Transmission of SARS-CoV2: Updated Rapid Review","volume":"10","author":"Li","year":"2020","journal-title":"J Glob Health"},{"key":"B6","doi-asserted-by":"publisher","DOI":"10.1001\/jamapediatrics.2020.5052","article-title":"Assessment of 135 794 Pediatric Patients Tested for Severe Acute Respiratory Syndrome Coronavirus 2 Across the United States","volume":"175","author":"Bailey","year":"2021","journal-title":"JAMA Pediatr"},{"key":"B7","doi-asserted-by":"publisher","DOI":"10.1093\/cid\/ciaa556","article-title":"SARS-CoV-2 (COVID-19): What Do We Know About Children? 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