{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,5]],"date-time":"2026-09-05T01:35:11Z","timestamp":1788572111058,"version":"build-2803163510"},"reference-count":35,"publisher":"MDPI AG","issue":"2","license":[{"start":{"date-parts":[[2023,1,24]],"date-time":"2023-01-24T00:00:00Z","timestamp":1674518400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Serum Institute of India Pvt. Ltd."}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Vaccines"],"abstract":"<jats:p>Children are at risk of infection from severe acute respiratory syndrome coronavirus-2 virus (SARS-CoV-2) resulting in coronavirus disease (COVID-19) and its more severe forms. New-born infants are expected to receive short-term protection from passively transferred maternal antibodies from their mothers who are immunized with first-generation COVID-19 vaccines. Passively transferred antibodies are expected to wane within first 6 months of infant\u2019s life, leaving them vulnerable to COVID-19. Live attenuated vaccines, unlike inactivated or viral-protein-based vaccines, offer broader immune engagement. Given effectiveness of live attenuated vaccines in controlling infectious diseases such as mumps, measles and rubella, we undertook development of a live attenuated COVID-19 vaccine with an aim to vaccinate children beyond 6 months of age. An attenuated vaccine candidate (dCoV), engineered to express sub-optimal codons and deleted polybasic furin cleavage sites in the spike protein of the SARS-CoV-2 WA\/1 strain, was developed and tested in hamsters. Hamsters immunized with dCoV via intranasal or intramuscular routes induced high levels of neutralizing antibodies and exhibited complete protection against the SARS-CoV-2 wild-type isolates, i.e., the Wuhan-like (USA-WA1\/2020) and Delta variants (B.1.617.2) in a challenge study. In addition, the dCoV formulated with the marketed measles\u2013rubella (MR) vaccine, designated as MR-dCoV, administered to hamsters via intramuscular route, also protected against both SARS-CoV-2 challenges, and dCoV did not interfere with the MR vaccine-mediated immune response. The safety and efficacy of the dCoV and the MR-dCoV against both variants of SARS-CoV-2 opens the possibility of early immunization in children without an additional injection.<\/jats:p>","DOI":"10.3390\/vaccines11020255","type":"journal-article","created":{"date-parts":[[2023,1,25]],"date-time":"2023-01-25T03:53:18Z","timestamp":1674618798000},"page":"255","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":16,"title":["A Live Attenuated COVID-19 Candidate Vaccine for Children: Protection against SARS-CoV-2 Challenge in Hamsters"],"prefix":"10.3390","volume":"11","author":[{"given":"Rajeev","family":"Mehla","sequence":"first","affiliation":[{"name":"Serum Institute of India Pvt. Ltd., Pune 411028, Maharashtra, India"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Prasad","family":"Kokate","sequence":"additional","affiliation":[{"name":"Serum Institute of India Pvt. Ltd., Pune 411028, Maharashtra, India"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Sarika R.","family":"Bhosale","sequence":"additional","affiliation":[{"name":"Serum Institute of India Pvt. Ltd., Pune 411028, Maharashtra, India"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Vivek","family":"Vaidya","sequence":"additional","affiliation":[{"name":"Serum Institute of India Pvt. Ltd., Pune 411028, Maharashtra, India"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Shridhar","family":"Narayanan","sequence":"additional","affiliation":[{"name":"Foundation for Neglected Disease Research, Bengaluru 561203, Karnataka, India"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Radha. K.","family":"Shandil","sequence":"additional","affiliation":[{"name":"Foundation for Neglected Disease Research, Bengaluru 561203, Karnataka, India"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Mayas","family":"Singh","sequence":"additional","affiliation":[{"name":"Foundation for Neglected Disease Research, Bengaluru 561203, Karnataka, India"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0179-5138","authenticated-orcid":false,"given":"Gudepalya R.","family":"Rudramurthy","sequence":"additional","affiliation":[{"name":"Foundation for Neglected Disease Research, Bengaluru 561203, Karnataka, India"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Chakenahalli N.","family":"Naveenkumar","sequence":"additional","affiliation":[{"name":"Foundation for Neglected Disease Research, Bengaluru 561203, Karnataka, India"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Kumaraswamy","family":"Bharathkumar","sequence":"additional","affiliation":[{"name":"Foundation for Neglected Disease Research, Bengaluru 561203, Karnataka, India"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Rob","family":"Coleman","sequence":"additional","affiliation":[{"name":"Codagenix, Inc., Farmingdale, New York, NY 11735, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Steffen","family":"Mueller","sequence":"additional","affiliation":[{"name":"Codagenix, Inc., Farmingdale, New York, NY 11735, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Rajeev M.","family":"Dhere","sequence":"additional","affiliation":[{"name":"Serum Institute of India Pvt. Ltd., Pune 411028, Maharashtra, India"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Leena R.","family":"Yeolekar","sequence":"additional","affiliation":[{"name":"Serum Institute of India Pvt. Ltd., Pune 411028, Maharashtra, India"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2023,1,24]]},"reference":[{"key":"ref_1","unstructured":"World Health Organization (2022, December 06). Coronavirus (COVID-19) Dashboard. Available online: https:\/\/covid19.who.int."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"1180","DOI":"10.1136\/archdischild-2020-320042","article-title":"COVID-19 in Children: Analysis of the First Pandemic Peak in England","volume":"105","author":"Ladhani","year":"2020","journal-title":"Arch. Dis. 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