The Importance and Necessity for the Elderly to Receive the High Dose Influenza Vaccine

What is the High Dose Quadrivalent Influenza Vaccine?
Normally, the quadrivalent influenza vaccine regularly administered in Thailand has an effectiveness of about 70-90% in preventing influenza caused by the same or similar virus strains used in the vaccine production. Therefore, even those who have been vaccinated may still get the flu, but the severity of the illness will be reduced.
The High Dose quadrivalent influenza vaccine is indicated for the prevention of influenza and helps reduce hospitalization due to pneumonia related to influenza in elderly individuals aged 65 years and older. This is based on data from studies in the United States, European countries, and Canada, where this vaccine has been used for over 10 years and has been continuously improved for better efficacy.
Characteristics of the High Dose Influenza Vaccine
The important features and advantages of the High Dose influenza vaccine are as follows:
๐ Contains up to 4 times the amount of antigen to stimulate immunity
๐ Increases effectiveness in preventing influenza by up to 24% compared to the standard dose
๐ Can reduce the risk of hospitalization from complications caused by influenza, including:
๐ Pneumonia, with an additional 27.3% reduction
๐ Heart and respiratory diseases, with an additional 17.9% reduction
๐ Influenza itself, with an additional 11.7% reduction
๐ All causes related to influenza infection, with an additional 8.4% reduction
Risk Factors That Make Elderly People More Susceptible to Severe Symptoms or Death from Influenza Infection
1. Underlying Disease
Especially in elderly individuals and those with chronic diseases such as diabetes, cancer, and kidney disease. If infected with the influenza virus, there is a high risk of complications such as pneumonia, bronchitis, sinusitis, and it may be severe enough to cause death.
2. Frailty in the Elderly
Frailty is a condition between functional ability and disability, and between good health and illness, commonly found in the elderly. When elderly people get infected with influenza, about 10% lose their ability to perform daily activities independently and require assistance. Additionally, 50%-70% of hospitalized elderly patients often develop other complications, and some experience health deterioration, reduced quality of life, or death. About 85% of deaths from influenza occur in the elderly group.
3. Decreased or Declined Immunity (Immunosenescence)
Immunosenescence is the decline and deterioration of the immune system, affecting its ability to eliminate pathogens, aged cells, and infected cells from the body. Factors include:
๐ Being elderly (Aging Society)
๐ Nutritional deficiencies
๐ Exposure to toxins, chemicals, and free radicals
๐ Leaky gut syndrome and imbalance of gut microbiota
๐ Secondary infections
๐ Stress
๐ Diabetes
Therefore, patients, especially those aged 65 and older with decreased or declined immunity, have a higher chance of illness from infections. It is observed that during influenza outbreaks, the number of elderly patients requiring hospitalization increases.
Reasons and Necessity for Elderly People to Receive the High Dose Influenza Vaccine
Elderly people are at higher risk of severe complications from influenza compared to younger adults. According to the Department of Disease Control, elderly individuals or those with underlying diseases such as chronic obstructive pulmonary disease, asthma, heart disease, stroke, chronic kidney disease, and diabetes are at risk of severe symptoms requiring prolonged hospitalization, and some may even die.
Therefore, it is necessary for patients, especially the elderly, to receive the High Dose influenza vaccine to build better immunity against influenza infection and reduce hospitalization rates from complications such as pneumonia caused by influenza, respiratory diseases, and influenza itself.
Side Effects After Receiving the Influenza Vaccine in Elderly People Aged 65 and Over
Most vaccines currently used are highly safe, but some side effects may still occur. These are generally mild and acceptable, resolving within 2-3 days. The most common adverse reactions after vaccination include pain at the injection site, muscle pain, headache, and general discomfort. These symptoms usually appear within the first 3 days after vaccination and typically resolve within 3 days.
For consultation, inquiries, or to receive the High Dose Influenza Vaccine, please contact the General Internal Medicine Center, Building 1, 1st Floor, Phyathai 1 Hospital, Tel. 02-201-4600 ext. 2166, 2167
Source : Phyathai 1 Hospital
Independent Writer
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