Influenza vaccination in older people with diabetes and their household contacts

People with diabetes are at a higher risk of influenza infections and severe complications. The vaccination of close contacts could offer indirect protection to people with diabetes; this is known as "herd immunity." The aim of this study is to investigate the vaccination rates of people with diabetes and their household contacts in Hong Kong.

Face-to-face interviews with 158 patients diagnosed with Type 2 diabetes and aged ⩾65years were conducted in clinics. Telephone interviews were then conducted with 281 adult household contacts.

Seasonal influenza vaccination rates were 54.5% and 27.4%, in people with diabetes and their contacts, respectively. The vaccination status of patients was not significantly associated with the vaccination of their household contacts (p=0.073). Among household contacts, children or the elderly, the partners or couples of patients, and those with more hours of daily contact, or with chronic conditions, were associated with higher vaccination rates. However, only age remained significant after adjusting for confounding factors in logistic regression models.

The low vaccination rates of people with diabetes and their close contacts highlight the need to promote vaccination in susceptible populations and to educate the public about herd immunity.