In persons 60 years and older, there is a decrease in the immune response compared to younger people due to the aging process of the immune system, mainly due to involution of the thymus. This is manifested by a decrease in the number of naive T cells produced by the body (CD4 and CD8), an increase in the number of T cells in contact with antigens (CD4 and CD8), a decrease in T cell variability, etc. Monitoring of the literature and pharmacovigilance can provide information on safety vaccination against influenza in elderly and senile patients.
According to the instructions for medical use published in the GRLS, as well as the literature review of pharmacovigilance, the administration of any vaccines, including against influenza, may be associated with the risk of developing such adverse reactions as low-grade fever, malaise, weakness, sore throat, runny nose, headache. pain, allergic reactions (including immediate type), neuralgia, paresthesia, neurological disorders, myalgia. Literature monitoring and pharmacovigilance should be mandatory to minimize risks and increase the benefit / harm ratio. According to active monitoring of the efficacy and safety of influenza vaccination in Australia (the number of patients included in the study was 102 911, data were obtained on 73 892 patients; the number of people over 65 years of age was 4710), the use of influenza vaccines can also lead to the development of seizures. increased muscle tone, loss of consciousness. Some of the above adverse reactions are predictable and dose dependent. A literature review of pharmacovigilance has shown that the risk of complications is higher when using the influenza vaccine in combination with other vaccines, as well as in children aged 6 months to 4 years, and lower in people 65 years and older.
The use of influenza vaccines in high doses (60 μg of hemagglutinin for each strain, the total dose is 180 μg of hemagglutinin), as well as the introduction of adjuvants into their composition, can increase the effectiveness of vaccination in people 60 years and older. This has been shown by literature monitoring and pharmacovigilance. Despite the decline in the immune status of elderly patients due to the natural aging process, vaccination of the elderly and seniors continues to be the most effective and safe way to prevent influenza. To improve the effectiveness of vaccination of patients 60 years and older, it is possible to recommend, inter alia, the use of vaccines in high doses and the use of adjuvants in vaccines. In doing so, good pharmacovigilance practice should be maintained. Alarms of adverse drug events should always be included in the pharmacovigilance literature review.