{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,28]],"date-time":"2026-10-28T07:40:39Z","timestamp":1793173239914,"version":"4.5.0"},"reference-count":44,"publisher":"MDPI AG","issue":"10","license":[{"start":{"date-parts":[[2021,10,13]],"date-time":"2021-10-13T00:00:00Z","timestamp":1634083200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Luxembourg Ministry of Foreign and European Affairs","award":["Luxembourg-Laos Partnership for Research and Capacity Building in Infectious Disease Surveillance II"],"award-info":[{"award-number":["Luxembourg-Laos Partnership for Research and Capacity Building in Infectious Disease Surveillance II"]}],"id":[{"id":"https:\/\/ror.org\/00zryte34","id-type":"ROR","asserted-by":"crossref"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Pathogens"],"abstract":"<jats:p>Introduction: Measles is an endemic but largely neglected disease in Lao People\u2019s Democratic Republic. New-borns are protected by maternal antibodies, but antibody waning before measles vaccination at 9 months of age leaves infants susceptible to infection. In this study, the susceptibility window of infants was determined to generate scientific evidence to assess the national measles immunization strategy. Methods: Between 2015 and 2016, demographic data, medical history, and blood samples were collected from 508 mother-child pairs at the provincial hospital in Vientiane. The samples were screened with a commercial kit detecting anti-measles IgG antibodies. Results: The large majority (95.7%) of the mothers were seropositive for anti-measles IgG and antibody titers of the mothers and infants were highly correlated (p &lt; 0.01). While at birth 97.7% of the infants were seropositive, seropositivity rates decreased to 74.2% two months later to reach only 28.2% four months after birth (p &lt; 0.01). Just before the first dose of the measles-rubella vaccine, scheduled at 9 months of age, was actually given, less than 14% of the infants were seropositive. Conclusion: This alarmingly wide susceptibility gap due to rapid maternal antibody decay leaves infants at risk of measles infection and serious disease complications. A high herd immunity is crucial to protect young infants and can be achieved through improved routine vaccination coverage and (expanded age group) supplementary immunization activities.<\/jats:p>","DOI":"10.3390\/pathogens10101316","type":"journal-article","created":{"date-parts":[[2021,10,13]],"date-time":"2021-10-13T21:48:39Z","timestamp":1634161719000},"page":"1316","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":15,"title":["Waning of Maternal Antibodies against Measles Suggests a Large Window of Susceptibility in Infants in Lao People\u2019s Democratic Republic"],"prefix":"10.3390","volume":"10","author":[{"given":"Phonepaseuth","family":"Khampanisong","sequence":"first","affiliation":[{"name":"Institut Pasteur du Laos, Samsenthai Road, Ban Kao-Gnot, Sisattanak District, Vientiane P.O. Box 3560, Laos"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Maude","family":"Pauly","sequence":"additional","affiliation":[{"name":"Department of Infection and Immunity, Luxembourg Institute of Health, 29, rue Henri Koch, 4354 Esch-sur-Alzette, Luxembourg"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Phonethipsavanh","family":"Nouanthong","sequence":"additional","affiliation":[{"name":"Institut Pasteur du Laos, Samsenthai Road, Ban Kao-Gnot, Sisattanak District, Vientiane P.O. Box 3560, Laos"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Molly A.","family":"Vickers","sequence":"additional","affiliation":[{"name":"Department of Infection and Immunity, Luxembourg Institute of Health, 29, rue Henri Koch, 4354 Esch-sur-Alzette, Luxembourg"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5049-0544","authenticated-orcid":false,"given":"Siriphone","family":"Virachith","sequence":"additional","affiliation":[{"name":"Institut Pasteur du Laos, Samsenthai Road, Ban Kao-Gnot, Sisattanak District, Vientiane P.O. Box 3560, Laos"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Kinnaly","family":"Xaydalasouk","sequence":"additional","affiliation":[{"name":"Institut Pasteur du Laos, Samsenthai Road, Ban Kao-Gnot, Sisattanak District, Vientiane P.O. Box 3560, Laos"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Antony P.","family":"Black","sequence":"additional","affiliation":[{"name":"Institut Pasteur du Laos, Samsenthai Road, Ban Kao-Gnot, Sisattanak District, Vientiane P.O. Box 3560, Laos"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Claude P.","family":"Muller","sequence":"additional","affiliation":[{"name":"Department of Infection and Immunity, Luxembourg Institute of Health, 29, rue Henri Koch, 4354 Esch-sur-Alzette, Luxembourg"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5001-2128","authenticated-orcid":false,"given":"Judith M.","family":"H\u00fcbschen","sequence":"additional","affiliation":[{"name":"Department of Infection and Immunity, Luxembourg Institute of Health, 29, rue Henri Koch, 4354 Esch-sur-Alzette, Luxembourg"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2021,10,13]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"2490","DOI":"10.1016\/S0140-6736(17)31463-0","article-title":"Measles","volume":"390","author":"Moss","year":"2017","journal-title":"Lancet"},{"key":"ref_2","unstructured":"World Health Organization (2021, August 13). 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