Humoral immune response to influenza vaccination in patients from high risk groups

Influenza is one of the most common respiratory diseases. Infections caused by this virus may be very serious and can lead to severe complications. So far, the most effective method of protection against influenza is annual v accination. The Advisory Committee on Immunisation Practices recommends vac cination against influenza for some groups of people. Unfortunately, in spi te of these clear indications, a large number of patients are not vaccinate d. This article reviews the current scientific literature on immunological res ponse to influenza vaccination in patients who are at especially high risk for serious post-influenza complications and for whom immunisation against this virus is strongly recommended. Results of studies carried out in Polan d and other countries in elderly people, in patients with pulmonary disease s, renal diseases, diabetes mellitus, cancer and haemophilia, and in those with HIV infection are presented. In this review, we focus on the immune re sponse to haemagglutinin. There are some discrepancies between the results of studies carried out by different authors in high risk groups of patients . Some investigations indicated poorer humoral response to influenza vaccin e in these groups, while others showed responses comparable to those in hea lthy individuals. These differences may be explained by differences in type s and stages of the chronic diseases, in the treatment and composition of i nfluenza vaccines, and also patients' ages, vaccination history and prevacc ination antibody titres. Influenza vaccines are well tolerated in high risk patients, and all adverse reactions are generally mild and similar to thos e observed in healthy people. although, in some cases, immunological respon ses to influenza vaccination measured in the whale study group were poor, t here were some individual patients who, after vaccination, developed antiha ema-glutinin antibody titres which are considered to give protection agains t the infection or contribute to a milder course of the disease.