Older adults who received the quadrivalent (four-strain) high-dose flu shot (QIV-HD) were hospitalized less for influenza and other conditions compared with people who received the standard quadrivalent flu vaccine (QIV-SD), a new study shows.
The report, published on Jan. 27 in Clinical Microbiology and Infection, detailed a trial that occurred in the 2021-2022 flu season in the Northern Hemisphere. The team evaluated outcomes from a total of 12,477 people — 6,245 who took the QIV-HD vaccine and 6,232 who got the QIV-SD. On average, participants were 71.1 years old, and 47% were women. More than 20% had an underlying cardiovascular disease.
The team evaluated outcomes 14 days after vaccination through May 2022. Specifically, they wanted to compare outcomes in both groups for getting the flu and/or pneumonia, or being hospitalized for a respiratory ailment, cardiorespiratory issue and cardiovascular issues. The team also evaluated how many people were hospitalized for all causes, and those who died from any cause.
Those who had the QIV-HD vaccine had lower rates of hospitalization for flu and pneumonia. There were 10 events in the QIV-HD group compared with 33 in the QIV-SD group. The researchers said that the quadrivalent shot gave 60% better protection.
By the third week of 2022, the investigators said they could see trends that indicated the QIV-HD shot gave better protection. At that time, there were five events in the QIV-HD group and 15 in the QIV-SD group.
Also today, a study in BMC Infectious Diseases found that older adults have a higher risk for complications if they get both influenza and respiratory syncytial virus, or RSV, especially if they’re aged more than 65 years and have a high comorbidity burden and frailty. People typically don’t get flu and RSV together, but it can be serious when both infections occur.
The news comes as a World Health Organization report published Jan. 24 (covering data through Jan. 7 this year) indicated that flu prevalence still is on the rise in some countries in the Northern Hemisphere but is declining overall worldwide.
