A new research has found that repeated vaccinations for influenza result in reduced severity of the flu and hospital admissions in older adults.
The study was conducted by a group of Spanish researchers on people aged 65 and above, admitted to 20 different Spanish hospital institutions between 2013 and 2015. These people were observed over four seasons – to determine whether repeated vaccinations result in reduced severity of influenza.
Dr. Itziar Casado and Dr. Jesús Castilla from Instituto de Salud Pública de Navarra, Pamplona, Spain, along with co-authors wrote, “Repeated vaccination for influenza was highly effective in preventing severe and fatal infection caused by influenza in older adults”.
The group found that repeated vaccination for influenza was twice as effective in preventing the severity of the flu in people affected by the virus as compared to non-severe cases. It also added that the results were consistent in people, notwithstanding virus subtype, flu season, or patient’s age.
The authors concluded with: “Because severe cases of influenza may be prevented by 2 mechanisms, the effectiveness of vaccination against severe influenza may be greater than that for mild cases, and the benefit of influenza vaccination may be greater than that estimated in previous studies. The prevention of severe and fatal infection caused by influenza was observed mainly in patients who were vaccinated in both the current and previous seasons, which reinforces the recommendation of annual vaccination for influenza in older adults”.
The result was published in CMAJ (Canadian Medical Association Journal).