In February 2024 the Regenstrief Institute announced that two studies from the CDC’s VISION Network demonstrated the effectiveness of flu vaccines for “all ages” against “both moderate and severe flu” in the US during the 2022-2023 flu season.
“The prospect of the worrisome triple threat of COVID, RSV, and flu was assuaged last year by the effectiveness of flu vaccines.”
The studies explored the flu-associated emergency department (ED)/urgent care visits, which are indicative of “moderate disease”, and hospitalisation, indicative of “severe disease” for both paediatric and adult populations. This was a particularly interesting season to study in comparison with the previous two as “fewer individuals were social distancing or wearing masks”.
Vaccination was effective
The studies evaluated electronic health record data in three healthcare systems in California, Utah, Minnestoa, and Wisconsin. The authors were able to conclude that flu vaccination is likely to “substantially” reduce illness, death, and “strain on healthcare resources”. For children between the ages of 6 months and 17 years, hospital visits and hospitalisations were reduced “by almost half”. For adults of any age, ED visits were reduced “by almost half” and hospitalisations were reduced by “slightly more than a third”.
Dr Shaun Grannis, co-author of both studies and Regenstrief Institute vice president for data analytics as well as family practice physician, commented on the importance of understanding the effectiveness of these vaccines “to ensure that our processes for forecasting” are working and could be “translatable to other diseases”.
“Given influenza’s significant disease burden – for example the H1N1 (swine) flu killed over a quarter of a million people worldwide in 2009-2010 – we want to make sure that we understand virus trends as well as other factors and that we’re continuing to do as well and as much as we can to reduce to the flu disease burden.”
Dr Grannis emphasised that “the dynamics of flu” differ between children and adults. However, for both groups “vaccination significant reduced” the risks of moderate or severe disease, which is “encouraging”.
“I’m hopeful that we will see similar or even better vaccine effectiveness during the current flu season. Even if they do experience symptoms, people who are vaccinated typically tend to have milder, shorter cases or the flu, a viral illness which can carry a severe disease burden.”
Dr Grannis urged “everyone” to get vaccinated for flu every year from the perspective of research and primary care.
“It’s good for each person’s health and the health of your community.”
The articles can be read at the following links, although they are not open access. For the paediatric study click here, and for the adult study click here.
We have a whole track dedicated to influenza and respiratory disease at the Congress in Washington, so do get your tickets to join us in April if this is of interest, and don’t forget to subscribe here.
