{"id":41112,"date":"2021-09-17T07:21:26","date_gmt":"2021-09-17T07:21:26","guid":{"rendered":"https:\/\/i-base.info\/htb\/?p=41112"},"modified":"2021-09-19T21:45:15","modified_gmt":"2021-09-19T21:45:15","slug":"neutralising-antibody-levels-from-covid-vaccines-correlate-negatively-with-age","status":"publish","type":"post","link":"https:\/\/i-base.info\/htb\/41112","title":{"rendered":"Neutralising antibody levels from COVID vaccines correlate negatively with age"},"content":{"rendered":"<div><\/div>\n<div>\n<p class=\"HTBsubhead3authorcredit\"><span lang=\"EN-US\"><strong><img loading=\"lazy\" decoding=\"async\" class=\" alignright\" src=\"https:\/\/i-base.info\/wp-content\/uploads\/2020\/03\/COVID-19-graphic.png\" width=\"231\" height=\"142\" \/>Simon Collins, HIV i-Base<\/strong><\/span><\/p>\n<\/div>\n<div>\n<p class=\"HTBBODYtext\"><strong>A small US study looking at levels of neutralising antibody levels after a complete Pfizer vaccine schedule correlated negatively with age, with lowest levels in the oldest participants.<\/strong><\/p>\n<\/div>\n<div>\n<p class=\"HTBBODYtext\">The study included 50 people, half women, with median age 50 years and ranging from 21 to 82.<\/p>\n<\/div>\n<div>\n<p class=\"HTBBODYtext\">The study reported strength of response against the original US strain and the P.1 variant, which were reduced by approximately 75%.<\/p>\n<\/div>\n<div>\n<p class=\"HTBBODYtext\">Although the overall association with age was highly significant, there was also considerable variance in the results (p=0.002; R<sup>2<\/sup>\u2009=\u20090.19).<\/p>\n<\/div>\n<div>\n<p class=\"HTBBODYtext\"><i>\u201cFor the USA-WA1\/2020 strain, the youngest participants (20 to 29 years; n\u2009=\u20098) had a <span lang=\"EN-US\">geometric mean titre (<\/span><\/i><i>GMT) of 938 (95% CI: 608 to 1447) and the oldest participants (70 to 82 years; n\u2009=\u20099) had a GMT of 138 (95% CI: 74 to 257), representing an 85% reduction (p&lt;0\u2009.001). For the P1 variant, the youngest participants had a GMT of 165 (95% CI: 78 to 349) and the oldest participants had a GMT of 66 (95% CI: 51 to 86), representing a 60% reduction (p=0.03).\u201d<\/i><\/p>\n<\/div>\n<div>\n<p class=\"HTBBODYtext\">Importantly, although levels of neutralising antibodies strongly correlate with levels of protection, the relevant threshold for protection has not yet been determined.<\/p>\n<\/div>\n<div>\n<p class=\"HTBBODYtext\">Ref: Bates TA et al. Age-dependent neutralization of SARS-CoV-2 and P.1 variant by vaccine immune serum samples.<b><\/b>JAMA<i>.\u00a0<\/i>doi:10.1001\/jama.2021.11656. (21 July 2021).<br \/>\n<a href=\"https:\/\/jamanetwork.com\/journals\/jama\/fullarticle\/2782428\">https:\/\/jamanetwork.com\/journals\/jama\/fullarticle\/2782428<\/a><\/p>\n<p><em>This article was first posted on 2 August 2921.<\/em><\/p>\n<\/div>\n","protected":false},"excerpt":{"rendered":"<p>Simon Collins, HIV i-Base A small US study looking at levels of neutralising antibody levels after a complete Pfizer vaccine schedule correlated negatively with age, with lowest levels in the oldest participants. The study included 50 people, half women, with &hellip;<\/p>\n","protected":false},"author":3,"featured_media":0,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[292,278],"tags":[],"class_list":["post-41112","post","type-post","status-publish","format-standard","hentry","category-covid-19-vaccine","category-covid-19"],"_links":{"self":[{"href":"https:\/\/i-base.info\/htb\/wp-json\/wp\/v2\/posts\/41112","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/i-base.info\/htb\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/i-base.info\/htb\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/i-base.info\/htb\/wp-json\/wp\/v2\/users\/3"}],"replies":[{"embeddable":true,"href":"https:\/\/i-base.info\/htb\/wp-json\/wp\/v2\/comments?post=41112"}],"version-history":[{"count":0,"href":"https:\/\/i-base.info\/htb\/wp-json\/wp\/v2\/posts\/41112\/revisions"}],"wp:attachment":[{"href":"https:\/\/i-base.info\/htb\/wp-json\/wp\/v2\/media?parent=41112"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/i-base.info\/htb\/wp-json\/wp\/v2\/categories?post=41112"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/i-base.info\/htb\/wp-json\/wp\/v2\/tags?post=41112"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}