Antibody-dependent enhancement of infection (ADE) is an in vitro serological phenomenon —or a group of phenomena—in which viral infection of susceptible cells is modified by the addition of virus-reactive antibody. Evidence suggests that ADE reflects immunologie processes that occur in vivo. Various severe and even fatal viral conditions of humans and animals, including dengue shock syndrome, the “early-death phenomenon” in experimental infections of immune animals, and other vaccine- and immunoglobulin-modified conditions, have been attributed to ADE by some researchers. ADE has caused great concern in relation to the development of vaccines against dengue virus and human immunodeficiency virus. More data are urgently needed on the mechanisms and determinants of ADE and on its alleged role in disease pathogenesis and in vaccine-associated phenomena.
— 読み進める academic.oup.com/cid/article-abstract/19/3/500/459343
Increasing evidence indicates that obesity is an independent risk factor for severe illness and death from covid-19.123456 In the UK, a population cohort study (428 225 participants; 340 admitted to hospital with confirmed covid-19, 44% of whom were overweight and 34% obese)1 and the OpenSAFELY study using linked electronic health records (17 425 445 participants, 5683 covid-19 deaths (29% overweight, 33% obese))2 have shown a dose-response relation between excess weight and severity of covid-19. After potential confounders, including age, sex, ethnicity, and social deprivation, were adjusted for, the relative risk of critical illness from covid-19 increased by 44% for people who were overweight (relative risk 1.44, 95% confidence interval 1.08 to 1.92) and almost doubled for those with obesity (1.97, 1.46 to 2.65) in the cohort study.1
Similarly, in the OpenSAFELY study, after all other risk factors (including comorbidities) were fully adjusted for, the risk of dying from covid-19 increased with obesity severity, from a 27% higher risk in the first obesity category (body mass index (BMI) 30-34.9; hazard ratio 1.27, 1.18 to 1.36) to more than doubling of the risk in the most obese category (BMI >40; 2.27, 1.99 to 2.58).2 Smaller studies from the Asia-Pacific region, Europe, and the US have confirmed these findings.3456
— 読み進める www.bmj.com/content/369/bmj.m2237