Research Roundup: COVID-19; Flu-Like Illness; Bariatric Surgery; Zika

CIDRAP: Plant-Derived Flu Vaccine Is Non-Inferior, Studies Show
A quadrivalent (four-strain) flu vaccine derived from the Nicotiana benthamiana plant, a relative of the tobacco plant, produces "non-inferior" results at minimum, according to the results of two phase 3 vaccine efficacy (VE) trials published in a Lancet study yesterday. The first study found a 35.1% absolute VE (95% CI, 17.9% to 48.7%) for respiratory illness caused by matched strains in adults 16 to 64 years of age, and the second reported an 8.8% relative VE (95% CI, -16.7% to 28.7%) across all strains in adults 65 and older compared with a chicken egg–derived quadrivalent inactivated vaccine. (10/14)

Pediatrics: Early Experience Of COVID-19 In A US Children's Hospital
We conducted a single-center retrospective cohort study of hospitalized children aged younger than 22 years with COVID-19 infection at Steven and Alexandra Cohen Children’s Medical Center at Northwell Health. Cases were identified from patients with fever and/or respiratory symptoms who underwent a nucleic acid amplification–based test for severe acute respiratory syndrome coronavirus 2. (Kainth et al, 10/1)

New England Journal of Medicine: Safety And Immunogenicity Of Two RNA-Based Covid-19 Vaccine Candidates 
In an ongoing, placebo-controlled, observer-blinded, dose-escalation, phase 1 trial conducted in the United States, we randomly assigned healthy adults 18 to 55 years of age and those 65 to 85 years of age to receive either placebo or one of two lipid nanoparticle–formulated, nucleoside-modified RNA vaccine candidates: BNT162b1, which encodes a secreted trimerized SARS-CoV-2 receptor–binding domain; or BNT162b2, which encodes a membrane-anchored SARS-CoV-2 full-length spike, stabilized in the prefusion conformation. The primary outcome was safety (e.g., local and systemic reactions and adverse events); immunogenicity was a secondary outcome. Trial groups were defined according to vaccine candidate, age of the participants, and vaccine dose level (10 μg, 20 μg, 30 μg, and 100 μg). In all groups but one, participants received two doses, with a 21-day interval between doses; in one group (100 μg of BNT162b1), participants received one dose. (Walsh et al, 10/14)

New England Journal of Medicine: Evaluation Of The MRNA-1273 Vaccine Against SARS-CoV-2 In Nonhuman Primates 
Vaccines to prevent coronavirus disease 2019 (Covid-19) are urgently needed. The effect of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccines on viral replication in both upper and lower airways is important to evaluate in nonhuman primates. (Corbett et al, 10/15)

CIDRAP: Flu-Like Illnesses Linked To Higher Heart And Stroke Risk Within The Month
In a study last week in the Journal of the American Heart Association, researchers analyzing New York public health data from 2004 to 2015 found an association between flu-like illness and increased risk for heart attack and stroke in adults regardless of flu vaccine effectiveness (VE). "We found that if someone's going to have a heart attack, it's going to occur within seven days of the flu-like illness, during the acute phase," study author Amelia Boehme, PhD, MSPH, says in an American Heart Association (AHA) press release. "With stroke, we see an increased risk seven to 15 days after, similar to heart attacks. But with stroke, there is an additional higher-risk period after 30 days." (10/12)

New England Journal of Medicine: Life Expectancy After Bariatric Surgery In The Swedish Obese Subjects Study 
Obesity shortens life expectancy. Bariatric surgery is known to reduce the long-term relative risk of death, but its effect on life expectancy is unclear. (Carlsson et al, 10/15)

The Lancet: Vertical Transmission Of Zika Virus And Its Outcomes: A Bayesian Synthesis Of Prospective Studies
Prospective studies of Zika virus in pregnancy have reported rates of congenital Zika syndrome and other adverse outcomes by trimester. However, Zika virus can infect and damage the fetus early in utero, but clear before delivery. The true vertical transmission rate is therefore unknown. We aimed to provide the first estimates of underlying vertical transmission rates and adverse outcomes due to congenital infection with Zika virus by trimester of exposure. (Ades et al, 10/14)