{"id":1720,"date":"2021-12-07T09:28:34","date_gmt":"2021-12-07T14:28:34","guid":{"rendered":"https:\/\/covidqanda.org\/?p=1720"},"modified":"2021-12-07T09:28:34","modified_gmt":"2021-12-07T14:28:34","slug":"what-is-the-definition-of-asymptomatic-can-vaccinated-individuals-be-asymptomatically-infected-and-transmit-the-virus-to-others","status":"publish","type":"post","link":"https:\/\/covidqanda.org\/?p=1720","title":{"rendered":"What is the definition of &#8220;asymptomatic&#8221;? Can vaccinated individuals be asymptomatically infected and transmit the virus to others?"},"content":{"rendered":"\n<p class=\"wp-block-paragraph\"><strong><span style=\"text-decoration: underline;\">Question:<\/span><\/strong>\u00a0I just want to be sure I\u2019m understanding the transmission potential of the virus\u2026..isn\u2019t it possible that a fully vaccinated person can \u201ccarry\u201d the infection and transmit it to an unvaccinated person, without actually being infected themselves? \u00a0Is that the definition of asymptomatic? \u00a0I just don\u2019t want to be THAT person who infects someone who\u2019s not as protected as I am.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><strong><span style=\"text-decoration: underline;\">Answer:<\/span><\/strong>\u00a0Your description of what it means to be asymptomatic is close, but not quite right.\u00a0 To clarify&#8211; &#8220;asymptomatic&#8221; means that a person\u00a0is infected with the virus, but is not experiencing any symptoms\u00a0(<strong>Box<\/strong>). Your concern that you could be infected without knowing it and then spread the infection to others, even if you&#8217;re vaccinated is valid; but if you are vaccinated, and especially if you are boosted, the risk is low.\u00a0 Specifically, if you are boosted, your risk of breakthrough infection is very low; the risk that the infection will present as &#8220;asymptomatic&#8221; is even lower (see below bullets).\u00a0 To further reduce risk, I recommend that you get boosted if you haven&#8217;t yet; and if you&#8217;re around someone who is not as protected (e.g. an immuno-compromised person or a young child), you could wear a mask and\/or give yourself a rapid test pre-visit to alleviate any lingering concern.\u00a0 Many parents of young children and caretakers of immunocompromised individuals have this concern and work to reduce risk by trying to avoid situations that put them into close contact with unvaccinated individuals.\u00a0 With that in mind, I&#8217;ll take the opportunity to nudge folks to get themselves vaccinated\/boosted and their eligible children vaccinated.\u00a0 The more of us who are vaccinated, the lower the risks to those of us all, especially those who are less protected.\u00a0\u00a0<\/p>\n\n\n\n<ul class=\"wp-block-list\"><li>Frequency of asymptomatic infection:&nbsp;Scientists estimate that about&nbsp;<a href=\"https:\/\/www.pnas.org\/content\/118\/34\/e2109229118\">one-third of all COVID cases are asymptomatic<\/a>&nbsp;with higher rates of asymptomaticity among children and individuals with no underlying conditions.&nbsp; When it comes to breakthrough infections (e.g. infections among fully vaccinated individuals), results from&nbsp;<a href=\"https:\/\/jamanetwork.com\/journals\/jama\/fullarticle\/2786040\">two studies<\/a>&#8212; a point prevalence survey during the Delta surge in England this summer and a randomized control trial comparing outcomes among mRNA vaccine vs. placebo recipients&#8211; both found that the risk of asymptomatic infection is two-thirds lower among vaccinated individuals as compared to unvaccinated individuals. Vaccination seems to greatly reduce the risk of asymptomatic infection, which is important for controlling the epidemic.&nbsp;&nbsp;<\/li><li>Onward transmission from asymptomatic infection:&nbsp;Onward transmission from asymptomatic infection does occur, but at a lower rate than symptomatic infections; one&nbsp;<a href=\"https:\/\/jammi.utpjournals.press\/doi\/full\/10.3138\/jammi-2020-0030\">systematic review<\/a>&nbsp;found, &#8220;the relative risk of asymptomatic transmission was 42% lower than that for symptomatic transmission.&#8221;&nbsp; Among vaccinated individuals, we know that the infectious&nbsp;period is shorter than among unvaccinated individuals, and as a recent&nbsp;<a href=\"https:\/\/jamanetwork.com\/journals\/jama\/fullarticle\/2786040\">JAMA editorial<\/a>&nbsp;explains, &#8220;vaccinated people are less likely to transmit SARS-CoV-2 to close contacts compared with unvaccinated people.&#8221;&nbsp; One&nbsp;<a href=\"https:\/\/www.nature.com\/articles\/d41586-021-02259-2\">small study<\/a>&nbsp;found that vaccinated individuals were 65% less likely than unvaccinated individuals to infect someone else.&nbsp; &nbsp;<\/li><li>Frequency of breakthrough infection:&nbsp;Breakthrough infections are much less frequent than infections among unvaccinated individuals.&nbsp; In&nbsp;<a href=\"https:\/\/covid.cdc.gov\/covid-data-tracker\/#rates-by-vaccine-status\">October in the US<\/a>, the rate of new cases per 100,000 individuals was 91\/100,000 among vaccinated individuals and 452\/100,000 among unvaccinated individuals.&nbsp; Furthermore, the COVID case rate is&nbsp;<a href=\"https:\/\/www.nejm.org\/doi\/full\/10.1056\/NEJMoa2114255\">much, much lower<\/a>&nbsp;among individuals who are boosted.&nbsp;<\/li><\/ul>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>Box. Definitions of asymptomatic and pre-symptomatic\u00a0<\/strong>(from\u00a0<a href=\"https:\/\/www.bmj.com\/content\/375\/bmj.n2342\">The BMJ<\/a>)<\/p>\n\n\n\n<figure class=\"wp-block-image size-large\"><img data-recalc-dims=\"1\" loading=\"lazy\" decoding=\"async\" width=\"723\" height=\"241\" src=\"https:\/\/i0.wp.com\/covidqanda.org\/wp-content\/uploads\/2021\/12\/image-1.png?resize=723%2C241&#038;ssl=1\" alt=\"\" class=\"wp-image-1721\" srcset=\"https:\/\/i0.wp.com\/covidqanda.org\/wp-content\/uploads\/2021\/12\/image-1.png?resize=1024%2C342&amp;ssl=1 1024w, https:\/\/i0.wp.com\/covidqanda.org\/wp-content\/uploads\/2021\/12\/image-1.png?resize=300%2C100&amp;ssl=1 300w, https:\/\/i0.wp.com\/covidqanda.org\/wp-content\/uploads\/2021\/12\/image-1.png?resize=768%2C257&amp;ssl=1 768w, https:\/\/i0.wp.com\/covidqanda.org\/wp-content\/uploads\/2021\/12\/image-1.png?w=1452&amp;ssl=1 1452w\" sizes=\"auto, (max-width: 723px) 100vw, 723px\" \/><\/figure>\n","protected":false},"excerpt":{"rendered":"<p>Question:\u00a0I just want to be sure I\u2019m understanding the transmission potential of the virus\u2026..isn\u2019t it possible that a fully vaccinated person can \u201ccarry\u201d the infection and transmit it to an unvaccinated person, without actually being infected themselves? \u00a0Is that the definition of asymptomatic? \u00a0I just don\u2019t want to be THAT person who infects someone who\u2019s [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"nf_dc_page":"","om_disable_all_campaigns":false,"_monsterinsights_skip_tracking":false,"_jetpack_newsletter_access":"","_jetpack_dont_email_post_to_subs":false,"_jetpack_newsletter_tier_id":0,"_jetpack_memberships_contains_paywalled_content":false,"_jetpack_feature_clip_id":0,"_jetpack_memberships_contains_paid_content":false,"footnotes":"","jetpack_post_was_ever_published":false},"categories":[85,38,60,17,34,18,64],"tags":[120],"class_list":["post-1720","post","type-post","status-publish","format-standard","hentry","category-children","category-immunity","category-risk","category-risk-reduction","category-symptoms","category-transmission-routes","category-vaccines","tag-asymptomatic","has-post-thumbnail","fallback-thumbnail"],"jetpack_sharing_enabled":true,"jetpack_featured_media_url":"","_links":{"self":[{"href":"https:\/\/covidqanda.org\/index.php?rest_route=\/wp\/v2\/posts\/1720","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/covidqanda.org\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/covidqanda.org\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/covidqanda.org\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/covidqanda.org\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=1720"}],"version-history":[{"count":1,"href":"https:\/\/covidqanda.org\/index.php?rest_route=\/wp\/v2\/posts\/1720\/revisions"}],"predecessor-version":[{"id":1722,"href":"https:\/\/covidqanda.org\/index.php?rest_route=\/wp\/v2\/posts\/1720\/revisions\/1722"}],"wp:attachment":[{"href":"https:\/\/covidqanda.org\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=1720"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/covidqanda.org\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=1720"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/covidqanda.org\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=1720"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}