Analysis finds positive risk-benefit for Novavax COVID vaccine

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An analysis of the Novavax COVID-19 vaccine using clinical and real-world data found that the benefits outweighed the risk of myocarditis or pericarditis, a team from the company reported in the March 16 edition of Vaccine.

teen vaccination — Photo courtesy of Novavax

Rare cases of myocarditis and pericarditis have been reported with the Novavax vaccine, similar to those reported with the mRNA vaccines. The adjuvanted protein-based vaccine, which is made on a more traditional platform, entered the US market in the fall of 2023 and has been authorized for emergency use in a two-dose series or as a booster in 45 countries.

For their analysis, the group used data from three sources: Novavax phase 3 clinical trials, estimates on US COVID disease burden between January and March of 2023, and real-world data on mRNA vaccine effectiveness in early 2023.

More than 1,800 cases prevented per 100,000 vaccinees

They estimated the vaccine prevented 1,805 COVID cases among 100,000 Novavax recipients, with 5.3 excess myocarditis or pericarditis hospitalizations and deaths. The number of hospitalizations and deaths prevented by the vaccine were also greater than vaccine-linked hospitalizations or deaths due to myocarditis or pericarditis.

Using a different sensitivity analysis that factored in lower vaccine efficacy, the number of prevented COVID cases was still greater than excess myocarditis and pericarditis events, including hospitalizations and deaths.

In the Novavax studies, there were five cases of myocarditis or pericarditis, including two that occurred within 7 days of vaccination. The two cases that occurred within a week of immunization were both reported in males. "Further work is needed to understand the benefit–risk balance for this demographic group," they wrote.

Psychiatric conditions linked to more COVID-19 hospital stays

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Stephanie Soucheray, MA

A new analysis of data in Influenza and Other Respiratory Viruses finds that the incidence of COVID-19 hospitalization is more than double among patients with any psychiatric disorder compared to adults with no psychiatric disorder.

The longitudinal study is based on electronic health records collected from four health systems and research centers in Indiana, Oregon, Texas, and Utah that partner with the Centers for Disease Control and Prevention (CDC). The study follow-up period lasted from December 2021 to August 2022, after both widespread vaccination campaigns and the Omicron variant became features of the pandemic in the United States.

Among the 2,436,999 adults included in the study, the median age was 47. Women composed 58.3% of the sample, 66.1% were White, 12.9% were Black, 12.0% were Hispanic, and 3.6% were Asian. Among participants, 41.6% were unvaccinated, 35.7% had received two doses, and 22.7% had received three doses.

Anxiety, mood disorders tied to hospitalization

A total of 538,034 adults had any psychiatric disorder, including 13.6% with anxiety disorders, 12.9% with mood disorders, 3.1% with trauma or stressor-related disorders, 1.9% with attention-deficit hyperactivity disorders, and 1.0% with psychotic disorders.

Adults with psychiatric disorders were hospitalized at a rate of 394 per 100,000 person-years, compared with a rate of 156 per 100,000 person-years for those without psychiatric disorder.

Psychiatric disorder was a significant predictor of COVID-19-associated hospitalization (adjusted hazard ratio, 1.27; 95% confidence interval, 1.18 to 1.37). Mood disorders, anxiety, and psychotic disorders were most associated with hospitalization.

Adjusted hazard ratios for hospitalization among vaccinated and unvaccinated adults with or without psychiatric disorders was the same.

The relative protection associated with mRNA vaccination was similar irrespective of psychiatric disorder status.

"The relative protection associated with mRNA vaccination was similar irrespective of psychiatric disorder status, underscoring the benefit of COVID-19 vaccination in this population," the authors concluded.

Full COVID vaccination tied to lower risk of heart conditions, death

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Mary Van Beusekom, MS

COVID vaccination — World Bank, Erick Kaglan / Flickr cc

Partially vaccinated or unvaccinated COVID-19 patients in California were at significantly higher risk for related non-respiratory consequences such as fever and abnormally rapid heart rate, as well as death in certain variant periods, a team led by University of California (UC) Irvine researchers reports in Vaccine.

The team conducted a longitudinal retrospective review of the electronic medical records of 63,454 UC COVID-19 patients of any age or hospitalization status to determine rates of non-respiratory symptoms, vaccination status, and death by 30 days after diagnosis by variant period from January 2020 to April 2022. The study period spanned the predominance of the wild-type, Alpha, Delta, and Omicron variants; vaccines were available to most people starting in the Delta wave.

Full vaccination was considered the receipt of at least two COVID-19 vaccine doses. Of all patients, 12.3% were fully vaccinated, and 87.6% had received one or no dose.

Vaccine protected against death even in younger people

Rates of fever, the most common symptom across all variant periods, were significantly higher among partially vaccinated or unvaccinated than in fully vaccinated patients during the Delta and Omicron waves.

Cardiac conditions were significantly more common in those not fully vaccinated amid Omicron, and tachycardia (abnormally rapid heart rate) occurred only in this group during Delta and Omicron. High blood pressure was the most common cardiac feature, regardless of variant period or vaccination status.

Our findings reveal distinct features of each wave and a significant association of most features with vaccination status.

Partially vaccinated and unvaccinated patients were at significantly higher risk for death in the Delta and Omicron periods (Delta odds ratio [OR], 1.64); Omicron OR, 1.96). Diabetes and gastrointestinal reflux disease were reported during all variant periods, regardless of vaccination status.

"Our findings reveal distinct features of each wave and a significant association of most features with vaccination status," the researchers wrote. "Although Omicron was shown to affect mostly younger people, the risk of death was still higher in the unvaccinated population, and thus the vaccine provided some protection from COVID-19 even among younger individuals."