{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,16]],"date-time":"2026-06-16T19:54:55Z","timestamp":1781639695064,"version":"3.54.5"},"reference-count":39,"publisher":"Oxford University Press (OUP)","issue":"6","license":[{"start":{"date-parts":[[2026,3,6]],"date-time":"2026-03-06T00:00:00Z","timestamp":1772755200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/academic.oup.com\/pages\/standard-publication-reuse-rights"}],"funder":[{"DOI":"10.13039\/501100019896","name":"Ministry of Health","doi-asserted-by":"publisher","id":[{"id":"10.13039\/501100019896","id-type":"DOI","asserted-by":"publisher"}]},{"name":"Government of Singapore"},{"name":"National Medical Research Council Office"},{"name":"MOH Holdings"},{"name":"National Epidemic Preparedness and Response R&D Programme","award":["MOH-001041, MOH-001073, and MOH-001446"],"award-info":[{"award-number":["MOH-001041, MOH-001073, and MOH-001446"]}]},{"DOI":"10.13039\/501100001349","name":"National Medical Research Council","doi-asserted-by":"publisher","award":["MOH-CNIG24jan-0010"],"award-info":[{"award-number":["MOH-CNIG24jan-0010"]}],"id":[{"id":"10.13039\/501100001349","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/100019579","name":"Singhealth","doi-asserted-by":"publisher","award":["CGApr25SPHSS13"],"award-info":[{"award-number":["CGApr25SPHSS13"]}],"id":[{"id":"10.13039\/100019579","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":[],"published-print":{"date-parts":[[2026,6,16]]},"abstract":"<jats:title>Abstract<\/jats:title>\n                  <jats:sec>\n                    <jats:title>Background<\/jats:title>\n                    <jats:p>While the real-world effectiveness of various pneumococcal vaccine formulations has been individually evaluated, comparative evaluations of 13-valent pneumococcal conjugate vaccine (PCV13)\/23-valent pneumococcal polysaccharide vaccine (PPSV23) and combinations thereof are limited. We evaluated the real-world vaccine effectiveness of PCV13 alone, PPSV23 alone, or PCV13 followed by PPSV23 amongst older adults.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Methods<\/jats:title>\n                    <jats:p>A population-based retrospective cohort study, including all adult Singaporeans aged \u226565 to 89 years from 1 January 2020 to 31 July 2024. The time to event from cohort enrollment to pneumococcal-related disease and all-cause pneumonia was measured, considering death as a competing risk. Cox regression models were used to estimate cause-specific hazards, with PCV13 alone, PPSV23 alone, and PCV13 followed by PPSV23 incorporated into models as time-dependent covariates. Vaccination status was assessed using the National Immunisation Registry; outcomes were identified using national healthcare claims data.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Results<\/jats:title>\n                    <jats:p>A total of 656 337 older Singaporeans were included; 348 831 (53.1%) remained unvaccinated by the study end date. Sequential PCV13 followed by PPSV23 significantly protected against pneumococcal-related disease (adjusted hazard ratio, 0.22 [95% confidence interval, .06\u2013.76]), pneumonia hospitalizations (0.94 [.91\u2013.97]), and all-cause mortality (0.70 [.67\u2013.74]). While PCV13 alone also reduced the risk of pneumonia hospitalization (adjusted hazard ratio, 0.96 [95% CI, .92\u2013.99]) and all-cause mortality (0.86 [95% confidence interval, .83\u2013.89]), vaccine effectiveness estimates were numerically lower than with sequential vaccination. For sequential vaccination, no significant waning of protection against all-cause pneumonia hospitalization or death was observed; a longer time interval (\u2265365 days) between PCV13 and PPSV23 was associated with a numerically lower risk of all-cause pneumonia hospitalization or death than a shorter interval (&amp;lt;365 days).<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Conclusions<\/jats:title>\n                    <jats:p>PCV13 followed by PPSV23 was associated with lower risk of pneumococcal-related disease, pneumonia, and all-cause mortality, supporting recommendations for sequential vaccination in older adults.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.1093\/infdis\/jiag147","type":"journal-article","created":{"date-parts":[[2026,3,4]],"date-time":"2026-03-04T12:48:20Z","timestamp":1772628500000},"page":"1069-1080","source":"Crossref","is-referenced-by-count":0,"title":["Real-World Effectiveness of Sequential Pneumococcal Vaccination in Older Adults: A Cohort Study"],"prefix":"10.1093","volume":"233","author":[{"given":"Yong Yi","family":"Tan","sequence":"first","affiliation":[{"name":"Lee Kong Chian School of Medicine, Nanyang Technological University ,","place":["Singapore"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Reen Wan Li","family":"Ho","sequence":"additional","affiliation":[{"name":"National Centre for Infectious Diseases ,","place":["Singapore"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jue Tao","family":"Lim","sequence":"additional","affiliation":[{"name":"Lee Kong Chian School of Medicine, Nanyang Technological University ,","place":["Singapore"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8217-7971","authenticated-orcid":false,"given":"Calvin J","family":"Chiew","sequence":"additional","affiliation":[{"name":"Communicable Diseases Agency ,","place":["Singapore"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Soon Kok","family":"Lim","sequence":"additional","affiliation":[{"name":"Communicable Diseases Agency ,","place":["Singapore"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"David Chien Boon","family":"Lye","sequence":"additional","affiliation":[{"name":"Lee Kong Chian School of Medicine, Nanyang Technological University ,","place":["Singapore"]},{"name":"National Centre for Infectious Diseases ,","place":["Singapore"]},{"name":"Communicable Diseases Agency ,","place":["Singapore"]},{"name":"Department of Infectious Diseases, Tan Tock Seng Hospital ,","place":["Singapore"]},{"name":"Yong Loo Lin School of Medicine, National University of Singapore ,","place":["Singapore"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Kelvin Bryan","family":"Tan","sequence":"additional","affiliation":[{"name":"Lee Kong Chian School of Medicine, Nanyang Technological University ,","place":["Singapore"]},{"name":"National Centre for Infectious Diseases ,","place":["Singapore"]},{"name":"Yong Loo Lin School of Medicine, National University of Singapore ,","place":["Singapore"]},{"name":"Duke-NUS Graduate Medical School, National University of Singapore ,","place":["Singapore"]},{"name":"Saw Swee Hock School of Public Health, National University of Singapore ,","place":["Singapore"]},{"name":"Ministry of Health, Government of Singapore ,","place":["Singapore"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6428-9999","authenticated-orcid":false,"given":"Liang En","family":"Wee","sequence":"additional","affiliation":[{"name":"Communicable Diseases Agency ,","place":["Singapore"]},{"name":"Duke-NUS Graduate Medical School, National University of Singapore ,","place":["Singapore"]},{"name":"Department of Infectious Diseases, Singapore General Hospital 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pneumococcal polysaccharide vaccine on the incidence of hospitalization with pneumonia in adults aged \u226565 years: retrospective cohort study using a population-based database in Japan","volume":"29","author":"Yamana","year":"2023","journal-title":"Clin Microbiol Infect"},{"key":"2026061615204963200_jiag147-B6","doi-asserted-by":"crossref","first-page":"1164","DOI":"10.3201\/eid3006.230975","article-title":"Follow-up study of effectiveness of 23-valent pneumococcal polysaccharide vaccine against all-type and serotype-specific invasive pneumococcal disease, Denmark","volume":"30","author":"Nielsen","year":"2024","journal-title":"Emerg Infect Dis"},{"key":"2026061615204963200_jiag147-B7","doi-asserted-by":"crossref","first-page":"832","DOI":"10.1093\/cid\/ciab1051","article-title":"Effectiveness of 13-valent pneumococcal conjugate vaccine against medically attended lower respiratory tract infection and pneumonia among older 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