Influenza as a threat to cardiovascular health and the role of vaccination in risk reduction

The different types of cardiovascular diseases, including coronary heart disease, cardiac arrhythmias and heart failure are highly prevalent in the society. Cardiovascular diseases are the leading cause of mortality. Although the influenza is forced out from the mainstream of thinking nowadays because of the ongoing SARS-CoV-2 pandemic, it still has its serious epidemiological significance. The seasonal influenza epidemic often contributes to mortality mainly, but not exclusively among old, multi-morbid patients. There are a vast number of scientific publications and evidence which prove and emphasize the synergic health-destroying and mortality-increasing effect of co-existing cardiovascular disease and influenza. Moreover, the beneficial effect of vaccination against influenza infection and its major role in prevention is also well documented. The SARS-CoV-2 pandemic enforces the importance of influenza vaccination because both viruses can lead to severe or often fatal disease, especially among old and frail patients. In addition, the younger population can be far more vulnerable against the novel coronavirus in the case of a co-existing influenza infection. International guidelines recommend influenza vaccination for patients having heart disease, like for other high-risk populations. Despite the nationally reimbursed, cost-free vaccines, the influenza vaccination rate of the society is still low not just in Hungary but also internationally. The authors review the effect of influenza infection on heart diseases, and draw attention to the role of influenza vaccination in decreasing cardiovascular morbidity and mortality.