- Immunological memory to SARS-CoV-2 assessed for greater than six months after infection
Understanding immune memory to SARS-CoV-2 is critical for improving diagnostics and vaccines, and for assessing the likely future course of the pandemic. Authors analyzed multiple compartments of circulating immune memory to SARS-CoV-2 in 185 COVID-19 cases, including 41 cases at ≥6 months post-infection. Spike IgG was relatively stable over 6+ months. Spike-specific memory B cells were more abundant at 6 months than at 1 month. SARS-CoV-2-specific CD4+ T cells and CD8+ T cells declined with a half-life of 3-5 months. By studying antibody, memory B cell, CD4+ T cell, and CD8+ T cell memory to SARS-CoV-2 in an integrated manner, each component of SARS-CoV-2 immune memory exhibited distinct kinetics. Authors speculate that durable immunity to COVID-19 is possible in most individuals.
- Sixty-Day Outcomes Among Patients Hospitalized With COVID-19
This observational cohort study looked at patients hospitalized with COVID-19 (discharged between 16 March and 1 July 2020) at 38 hospitals participating in the MI-COVID19 initiative. Of 1648 patients with COVID-19 admitted to 38 hospitals, 398 (24.2%) died during hospitalization and 1250 (75.8%) survived. Of 1250 patients discharged alive, 975 (78.0%) went home whereas 158 (12.6%) were discharged to a skilled nursing or rehabilitation facility. By 60 days after discharge, an additional 84 patients (6.7% of hospital survivors and 10.4% of intensive care unit [ICU]-treated hospital survivors) had died, bringing the overall mortality rate for the cohort to 29.2%, and 63.5% for the 405 patients who received treatment in an ICU. Within 60 days of discharge, 189 patients (15.1% of hospital survivors) were rehospitalized.
- Infection fatality rate of SARS-CoV2 in a super-spreading event in Germany
A SARS-CoV2 super-spreading event occurred during a 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). 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.
- Safety and immunogenicity of ChAdOx1 nCoV-19 vaccine administered in a prime-boost regimen in young and old adults (COV002): a single-blind, randomised, controlled, phase 2/3 trial
In this report of the phase 2 component of a single-blind, randomised, controlled, phase 2/3 trial (COV002), healthy adults aged 18 years and older were enrolled at two UK clinical research facilities, in an age-escalation manner, into 18–55 years, 56–69 years, and 70 years and older immunogenicity subgroups. ChAdOx1 nCoV-19 appears to be better tolerated in older adults than in younger adults and has similar immunogenicity across all age groups after a boost dose. Further assessment of the efficacy of this vaccine is warranted in all age groups and individuals with comorbidities.
- FDA Authorizes First COVID-19 Test for Self-Testing at Home
The U.S. Food and Drug Administration issued an emergency use authorization (EUA) for the first COVID-19 diagnostic test for self-testing at home and that provides rapid results. The Lucira COVID-19 All-In-One Test Kit is a molecular (real-time loop mediated amplification reaction) single use test that is intended to detect the novel coronavirus SARS-CoV-2 that causes COVID-19. The Lucira COVID-19 All-In-One Test Kit test has been authorized for home use with self-collected nasal swab samples in individuals age 14 and older who are suspected of COVID-19 by their health care provider. It is also authorized for use in point-of-care (POC) settings (e.g., doctor’s offices, hospitals, urgent care centers and emergency rooms) for all ages but samples must be collected by a healthcare provider when the test is used at the POC to test individuals younger than 14 years old. The test is currently authorized for prescription use only.