{"id":1184,"date":"2021-03-01T09:12:04","date_gmt":"2021-03-01T14:12:04","guid":{"rendered":"https:\/\/covidqanda.org\/?p=1184"},"modified":"2021-03-01T09:12:04","modified_gmt":"2021-03-01T14:12:04","slug":"are-anal-swabs-better-at-detecting-covid-19","status":"publish","type":"post","link":"https:\/\/covidqanda.org\/?p=1184","title":{"rendered":"Are anal swabs better at detecting COVID-19?"},"content":{"rendered":"\n<p class=\"wp-block-paragraph\"><strong><span style=\"text-decoration: underline;\">Question:<\/span><\/strong>\u00a0Are anal swabs better at detecting COVID-19 than nasal swabs?<\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><strong><u>Answer:<\/u>\u00a0<\/strong>Anal swabs have been in the news quite a bit in the past week or so with the revelation that the Government of China <a href=\"https:\/\/www.nbcnews.com\/news\/world\/u-s-diplomats-china-subjected-anal-swab-testing-covid-19-n1258844\">subjected US diplomats<\/a> to anal swab tests for COVID-19.\u00a0 This news follows <a href=\"https:\/\/www.forbes.com\/sites\/roberthart\/2021\/01\/27\/china-deploys-anal-swab-tests-to-detect-high-risk-covid-19-cases\/?sh=70b42a926e81\">reporting from <em>Fobes<\/em><\/a>\u00a0and <em><a href=\"https:\/\/www.reuters.com\/article\/us-health-coronavirus-china-testing-idUSKBN29W1RN\">Reuters<\/a><\/em>\u00a0from late January 2021 that China had begun to use the tests for high-risk individuals, including passengers arriving to Beijing and individuals in quarantine.\u00a0 Anal swab tests include the insertion of a cotton-tipped swab 1-2 inches into the rectum to collect a sample for PCR testing.\u00a0 The tests are clearly far more invasive than nasal and throat swabs.\u00a0 Based on the evidence I&#8217;ve read (further described herein), unless the testing involves very young children, anal swabs are not meaningfully better at detecting active infection.<\/p>\n\n\n\n<ul class=\"wp-block-list\"><li><strong>The virus is detectable in stool for a longer period than in nasal\/throat cultures,&nbsp;but this finding is not necessarily clinically meaningful.<\/strong>&nbsp;<a href=\"https:\/\/onlinelibrary.wiley.com\/doi\/10.1002\/jmv.26007\">Evidence from a pooled analysis of 8 cohort studies indicates<\/a>&nbsp;and a <a href=\"https:\/\/www.ncbi.nlm.nih.gov\/pmc\/articles\/PMC7461227\/\">systematic review of 95 studies<\/a> found that the virus is detectable for a longer period of time in stool samples compared with nasal\/throat samples.&nbsp; However, just because anal swabs are better able to find viral particles does not mean that they are better able to find active infections. A longer duration of viral shedding in the gastro-intestinal tract does not necessarily equate to a longer-duration of infectivity.&nbsp; In fact, <a href=\"https:\/\/www.cdc.gov\/coronavirus\/2019-ncov\/hcp\/duration-isolation.html\">available data show<\/a> that clinically recovered adults with prolonged viral shedding have not transmitted SARS-Cov-2 to others.&nbsp; As a result, <a href=\"https:\/\/www.cdc.gov\/coronavirus\/2019-ncov\/hcp\/duration-isolation.html\">CDC does not recommend<\/a> using a testing-based strategy to end isolation (except among severely immunocompromised patients) because viral shedding can last much longer than infectivity and sickness.&nbsp;&nbsp;<\/li><li><strong>Anal swab testing may be worthwhile if a young child presents with COVID-19 symptoms\/exposure, but tests negative from nasal\/throat swab. <\/strong>Based on their experience treating an infant, the <a href=\"https:\/\/www.ncbi.nlm.nih.gov\/pmc\/articles\/PMC7200387\/\">doctors who authored this case study concluded<\/a>,&nbsp;&#8220;Physicians should be aware that asymptomatic or mildly ill children with history of exposure and negative pharyngeal\/nasal swabs and positive anal swabs are potential sources of infection via fecal\u2013oral transmission for COVID-19. In addition to nasal\/pharyngeal swabs, we believe that children should be tested for SARS-CoV-2 using anal swabs.&#8221;<\/li><li><strong>Fecal\/oral transmission remains a theoretical concern.<\/strong>&nbsp;Because SARS-CoV-2 can be present in stool, the role of fecal\/oral transmission is a possibility.&nbsp; This is yet another reason that good hand washing behavior is so important!<\/li><\/ul>\n","protected":false},"excerpt":{"rendered":"<p>Question:\u00a0Are anal swabs better at detecting COVID-19 than nasal swabs? Answer:\u00a0Anal swabs have been in the news quite a bit in the past week or so with the revelation that the Government of China subjected US diplomats to anal swab tests for COVID-19.\u00a0 This news follows reporting from Fobes\u00a0and Reuters\u00a0from late January 2021 that China [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":1185,"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":[50,6,18],"tags":[41],"class_list":["post-1184","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-guidelines","category-testing","category-transmission-routes","tag-pcr","fallback-thumbnail"],"jetpack_sharing_enabled":true,"jetpack_featured_media_url":"https:\/\/i0.wp.com\/covidqanda.org\/wp-content\/uploads\/2021\/03\/March-1.jpg?fit=225%2C225&ssl=1","_links":{"self":[{"href":"https:\/\/covidqanda.org\/index.php?rest_route=\/wp\/v2\/posts\/1184","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=1184"}],"version-history":[{"count":1,"href":"https:\/\/covidqanda.org\/index.php?rest_route=\/wp\/v2\/posts\/1184\/revisions"}],"predecessor-version":[{"id":1186,"href":"https:\/\/covidqanda.org\/index.php?rest_route=\/wp\/v2\/posts\/1184\/revisions\/1186"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/covidqanda.org\/index.php?rest_route=\/wp\/v2\/media\/1185"}],"wp:attachment":[{"href":"https:\/\/covidqanda.org\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=1184"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/covidqanda.org\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=1184"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/covidqanda.org\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=1184"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}