{"id":84,"date":"2020-10-25T22:08:00","date_gmt":"2020-10-25T22:08:00","guid":{"rendered":"https:\/\/covidqanda.org\/?p=84"},"modified":"2020-11-08T22:13:18","modified_gmt":"2020-11-08T22:13:18","slug":"whats-the-dose-response-relationship-to-disease-severity","status":"publish","type":"post","link":"https:\/\/covidqanda.org\/?p=84","title":{"rendered":"What’s the dose-response relationship to disease severity?"},"content":{"rendered":"\n

Question:<\/strong> What\u2019s the latest research on dose response for exposure to COVID-19 and what can it tell us about our risk choices?<\/p>\n\n\n\n

Answer:<\/strong> We know that the more virus a person is exposed to, the higher their risk of being infected (for more background, see Q&A of 5\/20<\/a> #Viral Load, Q&A of 5\/12<\/a> #Risk). This is a big reason why public health experts recommend keeping interactions where social distancing isn\u2019t possible as brief as possible (<15 minutes). Findings published last week<\/a> in CDC\u2019s MMWR<\/em> also indicate that multiple brief exposures over 24 hours that cumulate in exposure time of 15+ minutes can result in infection, hence CDC\u2019s recent \u201cclose contact\u201d definition change (discussed in Q&A of 10\/22<\/a> #Incubation). It\u2019s also why mask wearing is so key! And why outdoors is safer than indoors.<\/p>\n\n\n\n

When it comes to the relationship between initial exposure dose and disease outcome, we are far less certain as the science is still emerging. Some scientists have hypothesized that lower initial exposure dose could be an important factor for asymptomatic infection. And this perspective, \u201cFacial Masking for Covid-19 \u2014 Potential for \u201cVariolation\u201d as We Await a Vaccine<\/a>,\u201d published in the New England Journal of Medicine<\/em> last month hypothesizes that by limiting initial exposure dose, mask wearing could \u201creduce the severity of disease and ensure that a greater proportion of new infections are asymptomatic.\u201d Here are a few interesting findings, which point to the potential of a relationship between exposure dose and disease outcome:<\/p>\n\n\n\n