COVID-19: Early Vaccine Results / Psychiatric Symptoms / Prevalence in L.A. County / Neutralizing Antibody

By Kelly Young

Edited by David G. Fairchild, MD, MPH, and Jaye Elizabeth Hefner, MD

Here's a look at some of the latest news on novel coronavirus disease (COVID-19):

Phase I vaccine results: A messenger RNA (mRNA) vaccine has shown promise against SARS-CoV-2 in humans in a phase I study. All 45 participants in the trial seroconverted by day 15 after the first dose. Two weeks after the second dose of the 25-µg vaccine, levels of binding antibodies were similar to those observed in convalescent sera from recovered patients. The first eight participants given the vaccine all developed neutralizing antibodies (data were available for only these 8). Adverse events were rare. In a separate study, the vaccine blocked viral replication in the lungs of mice infected with SARS-CoV-2. Phase II of the study in humans is expected to begin shortly, and phase III could begin in July.

Psychiatric symptoms: Coronavirus infection is associated with a range of psychiatric outcomes, according to a meta-analysis in the Lancet Psychiatry. Most studies evaluated SARS-CoV and MERS-CoV infections in hospitalized patients, and signs of delirium were common in the acute phase of infection. Additionally, in COVID-19 patients in intensive care, roughly two thirds had delirium. Symptoms of depression, anxiety, fatigue, and post-traumatic stress disorder were common in the post-illness phases of MERS and SARS, but there are not enough data yet on COVID-19. Commentators write: "We conclude that findings from previous coronavirus outbreaks are useful, but might not be exact predictors of prevalences of psychiatric complications for patients with COVID-19. The [researchers'] warning ... that we should prepare to treat large numbers of patients with COVID-19 who go on to develop delirium, post-traumatic stress disorder, anxiety, and depression is an important message for the psychiatric community."

SARS-CoV-2 prevalence in L.A. County: The community prevalence of antibodies to SARS-CoV-2 was 4.65% in Los Angeles County in early April, reports a JAMA research letter. Researchers tested over 850 randomly sampled adults in Los Angeles County for SARS-CoV-2 antibodies on April 10–14. Based on this prevalence, the authors estimate that roughly 367,000 residents of the county had SARS-CoV-2 antibodies. The official number of confirmed infections was only 8430. The authors do caution, however, that selection bias is likely.

SARS antibody: Researchers have identified an antibody in a patient who was infected with SARS-CoV in 2003 that effectively neutralizes SARS-CoV-2. The study results of the S309 antibody are reported in Nature. The authors write: "These results pave the way for using S309- and S309-containing antibody cocktails for prophylaxis in individuals at high risk of exposure or as a post-exposure therapy to limit or treat severe disease."