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Studies on Influenza Vaccine

25 December 2023

Scientific reviews and studies demonstrate that the influenza vaccine is both safe and effective.
Influenza causes mortality, especially among older people. Additionally, the risk of influenza complications is further increased by underlying illnesses.

The vaccine has been shown to be effective in preventing influenza and its complications and can save lives even when it does not prevent the spread of the disease. The vaccine has been proven to be safe and any side effects are mostly mild and transient.

In view of the available studies, it is recommended to receive an annual flu shot as soon as the HMOs' immunization program launches (often in September or October).

The COVID-19 pandemic years in Israel were not difficult in terms of influenza morbidity. The reason is probably related to the competition between the viruses, as well as to social distancing. Now that the pandemic has passed, influenza is expected to return, and we should prepare for it as we would for any influenza season before the pandemic.

Have you received a notice calling you to be vaccinated against influenza, but you are hesitating? Do you worry about the vaccine’s side effects? Several studies have addressed these concerns in recent years.

Influenza vaccine can prevent you from catching influenza

Vaccine efficacy tests conducted in the United States and Israel have demonstrated that influenza vaccines can be effective in preventing illness complications by 40%–60%. In fact, influenza vaccines are estimated to prevent millions of influenza cases around the world each year.

Prior to the COVID-19 pandemic, research conducted during the 2019–2020 flu season demonstrated that the vaccination effectively stopped 7.5 million cases of the flu, almost 105,000 hospital admissions linked to the flu, and roughly 6,300 cases of mortality caused by the flu.

Influenza vaccines prevent complications, severe morbidity, and mortality

A number of studies show that the influenza vaccine reduces the severity of the disease among individuals who have been vaccinated and caught the disease.

A study conducted in 2021 has proven that the vaccine reduces the risk of admission to the emergency room by 26%, death cases by 36% in comparison to individuals who have not been vaccinated.

According to a 2018 study, older people who had received the flu shot and were admitted to the hospital due to complications were 59% less likely to be transported to the emergency room than those who had not had the shot.

A study conducted between 2012 and 2015 showed that the influenza vaccine reduced the risk of admission to the emergency room by 82%.

Furthermore, the study has demonstrated that the vaccine helps shorten hospitalization in the emergency room by an average of four days in comparison to those who have not had the shot.

Influenza vaccines reduce the risk of hospitalization

A study conducted in 2017 showed that during the years 2009–2016, influenza vaccines reduced the risk of hospitalizations due to disease complications among vaccinated adults by 40%.

Influenza vaccines protect people with chronic diseases

The influenza vaccine has been proven to be effective in preventing hospitalizations among people with chronic diseases. The vaccine helps reduce heart attacks among people with cardiac diseases, especially those who have had a heart attack in the previous year.

The influenza vaccine has been proven to be effective in preventing hospitalizations among people with diabetes due to an exacerbation of their condition.

The influenza vaccine has been proven to be effective in preventing acute outbursts of COPD (Chronic Obstructive Pulmonary Disease).