{"id":23424,"date":"2023-02-28T04:23:00","date_gmt":"2023-02-27T20:23:00","guid":{"rendered":"http:\/\/csccm.org.cn\/?p=23424"},"modified":"2023-02-28T07:17:38","modified_gmt":"2023-02-27T23:17:38","slug":"bmj%e5%8f%91%e8%a1%a8%e6%96%87%e7%ab%a0%ef%bc%9a%e6%96%b0%e5%86%a0%e7%97%85%e6%af%92%e6%84%9f%e6%9f%93%e7%9a%84%e7%97%87%e7%8a%b6%e5%a6%82%e4%bd%95%e6%94%b9%e5%8f%98%ef%bc%9f","status":"publish","type":"post","link":"https:\/\/csccm.org.cn\/?p=23424","title":{"rendered":"[BMJ\u53d1\u8868\u6587\u7ae0]\uff1a\u65b0\u51a0\u75c5\u6bd2\u611f\u67d3\u7684\u75c7\u72b6\u5982\u4f55\u6539\u53d8\uff1f"},"content":{"rendered":"\n

Feature<\/strong> Covid Unanswered Questions<\/p>\n\n\n\n

How are covid-19 symptoms changing?<\/h1>\n\n\n\n

Mun-Keat Looi<\/h3>\n\n\n\n

BMJ<\/em>\u00a02023;\u00a0380\u00a0doi:\u00a0https:\/\/doi.org\/10.1136\/bmj.p3<\/a>\u00a0(Published 18 January 2023)Cite this as:\u00a0BMJ<\/em>\u00a02023;380:p3<\/h3>\n\n\n\n

With new variants and a changing landscape of vaccination and immunity, what do the symptoms of covid-19\u2014and our understanding of them\u2014now look like? Mun-Keat Looi<\/strong>reports<\/p>\n\n\n\n

How have covid symptoms changed since the start of the pandemic?<\/h2>\n\n\n\n

In the short space of a few years we\u2019ve seen surprising changes in the way covid-19 presents. At the start of the pandemic the first commonly reported symptoms were loss of smell and taste, followed by shortness of breath and a cough, followed by vascular injuries, says David Strain, senior clinical lecturer at the University of Exeter Medical School. \u201cThat became the standard that we expected,\u201d he says.<\/p>\n\n\n\n

Betty Raman, senior clinical research fellow in the Radcliffe Department of Medicine, University of Oxford, says, \u201cPeople presenting with the earlier variants would have quite severe cardiorespiratory or mostly respiratory symptoms in the acute phase with other symptoms too, like brain fog. Quite a significant proportion were admitted to hospital with the earlier variants.\u201d<\/p>\n\n\n\n

Since then there\u2019s been an evolution of symptom clusters and manifestations across the variants, she says, affected by the evolution of the virus itself but also by vaccines, the vaccine landscape, the use of other treatments, and people getting recurrent infections. This has led to falling hospital admissions and changes in the frequency of each symptom.<\/p>\n\n\n\n

Strain says that the loss of sense of smell and taste is nowhere near as prevalent as it used to be. \u201cThat really happened at the time of omicron,\u201d he says. \u201cOmicron subvariants BA.1 and BA.2 seemed to migrate from [infecting mainly] lungs and nervous tissue to the upper airways. BA.1 for many people was little more than a severe head cold.\u201d<\/p>\n\n\n\n

Raman adds that, while some people still experience brain fog, on a population scale this seems slightly less prevalent with newer variants and vaccines.<\/p>\n\n\n\n

Strain estimates that at the start of the pandemic infection resulted in vascular damage in around 15-20% of patients\u2014\u201cfor some this was simple \u2018covid toes,\u2019 but for others it was pulmonary emboli and acute kidney injury\u201d\u2014while a smaller proportion went on to experience a full cytokine storm and acute respiratory distress syndrome (ARDS). \u201cThankfully, ARDS has almost completely disappeared now that we\u2019ve got vaccination,\u201d he says. \u201cVery, very few people get onto that final stage.\u201d<\/p>\n\n\n\n

With vaccination, immunity from prior infection, and the evolution of omicron to cause overall less intense acute infection, the presentation of symptoms has evolved. Strain says that we now see mostly upper respiratory symptoms, fever, myalgia, fatigue, sneezing, sore throat, and cough. He notes that many of these are not specific to covid-19 and could also be a manifestation of other viral illnesses.<\/p>\n\n\n\n

World Health Organization list of covid-19 symptoms<\/h3>\n\n\n\n

Common<\/h4>\n\n\n\n