long Covid<\/strong><\/a> may remain locked in a prolonged battle with remnants of the coronavirus, producing inflammation while failing to effectively eliminate its source, new research suggests.<\/p>\nScientists at the University of California, San Francisco found extensive immune abnormalities in intestinal tissue taken from people with long Covid, including signs that some of the body\u2019s first-line defenses remained activated months or years after infection. At the same time, processes needed to recognize and destroy virus-containing cells were weakened.<\/p>\n
The findings, released in a preprint on Monday ahead of peer review, suggest an \u201cuncoordinated immune response\u201d in which inflammatory activity continues while mechanisms needed to eliminate its source are impaired, wrote researchers led by Michael Peluso and Timothy Henrich.<\/p>\n
While the study can\u2019t establish that lingering virus causes the immune abnormalities or long Covid itself, the findings could nonetheless influence the search for treatments. Antiviral drugs alone haven\u2019t shown clear benefits in trials of broadly defined long Covid, and the researchers said treatment may ultimately need to both target lingering virus and restore the immune system\u2019s ability to eliminate cells harboring it.<\/p>\n
Understanding what drives long Covid has become one of the most pressing unanswered questions left by the pandemic. Millions of people worldwide have experienced lasting symptoms after Covid-19, including fatigue, problems with memory and concentration and worsening illness after physical activity. The condition is also part of a broader and still poorly understood group of chronic illnesses that can follow infections, meaning insights into its biology could have implications well beyond Covid.<\/p>\n
RELATED ARTICLES<\/strong><\/p>\nThe UCSF researchers studied samples of the lower intestine from 44 people with long Covid and 13 people who had recovered completely. The biopsies were collected a median of almost two years after participants\u2019 first known SARS-CoV-2 infection. Researchers examined the samples using several methods to search for the virus and measure how thousands of genes and different types of immune cells were behaving.<\/p>\n
Evidence of persistent SARS-CoV-2 was found in the intestinal tissue of 12 \u2014 or 27 percent \u2014 of the people with long Covid, compared with one of the 13 recovered participants. The difference wasn\u2019t statistically significant, and the researchers cautioned that detecting viral genetic material doesn\u2019t establish that intact, infectious virus remains in the body.<\/p>\n
Still, they found both single- and double-stranded viral RNA in cells lining the intestine. Because those cells normally turn over within days, the finding suggests ongoing viral activity or that the cells are repeatedly being exposed to virus from elsewhere in the body, the researchers said.<\/p>\n
The immune abnormalities were much more pronounced in intestinal tissue than in blood, suggesting blood tests may miss important biological changes occurring inside tissues.<\/p>\n","protected":false},"excerpt":{"rendered":"A droplet falls from a syringe after a health care worker was injected with the Pfizer-BioNTech COVID-19 vaccine…\n","protected":false},"author":2,"featured_media":632589,"comment_status":"","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"footnotes":"","_share_on_mastodon":"0"},"categories":[78],"tags":[160,46779,64,18,135,19,17,66249,267284,1605,26534,267285,61328,7913,267286],"class_list":["post-632588","post","type-post","status-publish","format-standard","has-post-thumbnail","category-health","tag-coronavirus","tag-covid-pandemic","tag-covid-19","tag-eire","tag-health","tag-ie","tag-ireland","tag-long-covid","tag-michael-peluso","tag-san-francisco","tag-sars-cov-2","tag-timothy-henrich","tag-ucsf","tag-university-of-california","tag-viral-rna"],"share_on_mastodon":{"url":"https:\/\/pubeurope.com\/@ie\/117080663323536284","error":""},"_links":{"self":[{"href":"https:\/\/www.europesays.com\/ie\/wp-json\/wp\/v2\/posts\/632588","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.europesays.com\/ie\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.europesays.com\/ie\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.europesays.com\/ie\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/www.europesays.com\/ie\/wp-json\/wp\/v2\/comments?post=632588"}],"version-history":[{"count":0,"href":"https:\/\/www.europesays.com\/ie\/wp-json\/wp\/v2\/posts\/632588\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.europesays.com\/ie\/wp-json\/wp\/v2\/media\/632589"}],"wp:attachment":[{"href":"https:\/\/www.europesays.com\/ie\/wp-json\/wp\/v2\/media?parent=632588"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.europesays.com\/ie\/wp-json\/wp\/v2\/categories?post=632588"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.europesays.com\/ie\/wp-json\/wp\/v2\/tags?post=632588"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}
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A droplet falls from a syringe after a health care worker was injected with the Pfizer-BioNTech COVID-19 vaccine at a hospital in Providence, Rhode Island, United States, Dec 15, 2020. (PHOTO\/AP)<\/p>\n