Infection fatality rate of SARS-CoV2 in a super-spreading event in Germany

Abstract

A SARS-CoV2 super-spreading event occurred during carnival in a small town in Germany. Due to the rapidly imposed lockdown and its relatively closed community, this town was seen as an ideal model to investigate the infection fatality rate (IFR). Here, a 7-day seroepidemiological observational study was performed to collect information and biomaterials from a random, household-based study population. The number of infections was determined by IgG analyses and PCR testing. We found that of the 919 individuals with evaluable infection status, 15.5% (95% CI:[12.3%; 19.0%]) were infected. This is a fivefold higher rate than the reported cases for this community (3.1%). 22.2% of all infected individuals were asymptomatic. The estimated IFR was 0.36% (95% CI:[0.29%; 0.45%]) for the community and 0.35% [0.28%; 0.45%] when age-standardized to the population of the community. Participation in carnival increased both infection rate (21.3% versus 9.5%, p < 0.001) and number of symptoms (estimated relative mean increase 1.6, p = 0.007). While the infection rate here is not representative for Germany, the IFR is useful to estimate the consequences of the pandemic in places with similar healthcare systems and population characteristics. Whether the super-spreading event not only increases the infection rate but also affects the IFR requires further investigation.

SARS-CoV-2 Seroprevalence and Clinical Features of COVID-19 in a German Liver Transplant Recipient Cohort: A Prospective Serosurvey Study

“…Until study termination, about 37,000 PCR-proven SARS-CoV-2 infections had been documented in the study area (Baden-Württemberg). Recent German serosurveys provide a rough estimate of a factor of 4–10 of PCR-documented SARS-CoV-2 infections to overall serology-proven infections, proposing a seroprevalence of 1.3%-3.2% in southwestern Germany [ 16 , 17 ]. Taking into account this estimate, the prevalence of active or past SARS-CoV-2 infection in LT recipients is comparable to that in the general population.…”

SARS-CoV-2 antibody testing for estimating COVID-19 prevalence in the population

“…With commercial product development making a multitude of testing kits available 43 and priorities shifting from immediate containment toward gaining insights into the epidemiology of COVID-19 and SARS-CoV-2 infection, 20 many antibody testing studies have been started globally. Although a few serology studies of individuals with COVID-19 have already been published in peer-reviewed journals, 23 , 63 , 65 , 64 several studies investigating population-wide spread, including asymptomatic individuals, are still ongoing and only available as preprints, press releases, or newspaper articles. Hence, details regarding the exact antibody tests and selection criteria are only partially available.…”

“… 61 Iceland 30,576 estimated at 0.9% different criteria for subgroups includes a longitudinal assessment of antibody responses 4 months after infection Gudbjartsson et al. 63 Spain 60,983 ~5% Random ongoing study of random households, current results of rapid tests, measurements by immunoassays ongoing, reporting on a reliability study of lower accuracy of rapid tests than the manufacturer’s specifications ESTUDIO ENE-COVID19: PRIMERA RONDA 69 USA, Idaho 15,789 2.02% semi-random ongoing testing effort of volunteers who suspect they have contracted COVID-19; results as of June 14, 2020; non-profit initiative “Crush the Curve Idaho”; testing through the University of Washington Virology Department Bryan et al. 70 USA, Boston, MA 750 9.9% semi-random testing of volunteers, emphasis on asymptomatic individuals (residents having previously tested positive in a qRT-PCR test and/or symptoms were excluded) City of Boston Public Health Commission 71 USA, Chelsea, MA ~200 32% semi-random random volunteers, carried out by Massachusetts General Hospital Corcoran 72 USA, Indianapolis, IN >4,600 2.8% antibody, 1.7% qRT-PCR random to semi-random randomly selected individuals and volunteers tested with qRT-qPCR and antibody tests, carried out by Indiana University Richard M. Fairbanks School of Public Health, ongoing, 73 USA, Los Angeles, CA 846 4.1% Random University of Southern California and Los Angeles County Department of Public Health, drive-through antibody testing of participants recruited via a market research firm’s database representative of the county’s population University of Southern California and County of Los Angeles 74 US, New York, NY ~15,000 12.3% N/A testing efforts by the Wadsworth Center, the public health laboratory of the New York State Department of Health NY State COVID-19 Testing 75 …”

“… 69 , 77 A large-scale study of 30,576 individuals from Iceland also employed six different antibody tests, scoring positive when two specific tests passed. 63 …”

Overcoming Supply Shortage for SARS-CoV-2 Detection by RT-qPCR

“…Furthermore, the number of samples referred to our laboratory for SARS-CoV-2 RNA detection increased substantially following the rapid spread rate of the virus, which is attributed to its ability to be transmitted before becoming symptomatic [ 12 , 13 , 14 ]. Primers and probes, as well as new qPCR thermocyclers, were in short supply at their manufacturers [ 15 ], halting us from providing more tests to our patients.…”