Institute of Medical Microbiology and Hygiene, Molecular Microbiology (Virology), University of Regensburg, Franz-Josef-Strauß-Allee 11, 93053 Regensburg, Germany.
Institute of Clinical Microbiology and Hygiene, University Hospital Regensburg, Franz-Josef-Strauß-Allee 11, 93053 Regensburg, Germany.
Viruses. 2021 Jun 10;13(6):1118. doi: 10.3390/v13061118.
SARS-CoV-2 infection fatality ratios (IFR) remain controversially discussed with implications for political measures. The German county of Tirschenreuth suffered a severe SARS-CoV-2 outbreak in spring 2020, with particularly high case fatality ratio (CFR). To estimate seroprevalence, underreported infections, and IFR for the Tirschenreuth population aged ≥14 years in June/July 2020, we conducted a population-based study including home visits for the elderly, and analyzed 4203 participants for SARS-CoV-2 antibodies via three antibody tests. Latent class analysis yielded 8.6% standardized county-wide seroprevalence, a factor of underreported infections of 5.0, and 2.5% overall IFR. Seroprevalence was two-fold higher among medical workers and one third among current smokers with similar proportions of registered infections. While seroprevalence did not show an age-trend, the factor of underreported infections was 12.2 in the young versus 1.7 for ≥85-year-old. Age-specific IFRs were <0.5% below 60 years of age, 1.0% for age 60-69, and 13.2% for age 70+. Senior care homes accounted for 45% of COVID-19-related deaths, reflected by an IFR of 7.5% among individuals aged 70+ and an overall IFR of 1.4% when excluding senior care home residents from our computation. Our data underscore senior care home infections as key determinant of IFR additionally to age, insufficient targeted testing in the young, and the need for further investigations on behavioral or molecular causes of the fewer infections among current smokers.
2020 年春季，德国蒂申罗伊特县暴发了严重的 2019 冠状病毒病疫情，病死率（CFR）尤其高。为了估计 2020 年 6 月/7 月≥14 岁的蒂申罗伊特县人群的血清流行率、漏报感染和感染致死率（IFR），我们开展了一项基于人群的研究，包括对老年人的家访，并通过三种抗体检测方法分析了 4203 名参与者的 SARS-CoV-2 抗体。潜伏类分析得出该县标准化血清流行率为 8.6%，漏报感染率为 5.0 倍，总 IFR 为 2.5%。医务人员的血清流行率是两倍，当前吸烟者的感染率为三分之一，但登记的感染率相似。虽然血清流行率没有显示出年龄趋势，但年轻人的漏报感染率为 12.2 倍，而≥85 岁的老年人为 1.7 倍。60 岁以下年龄特异性 IFR ＜0.5%，60-69 岁为 1.0%，70 岁以上为 13.2%。老年人护理院占 COVID-19 相关死亡人数的 45%，70 岁以上人群的 IFR 为 7.5%，将老年人护理院居民从我们的计算中排除后，总 IFR 为 1.4%，这反映了老年人护理院感染是 IFR 的关键决定因素，除了年龄，年轻人的靶向检测不足，以及需要进一步调查吸烟与较少感染之间的行为或分子原因。
