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Taking up arms against the flu

27 Oct 2021

Guest post: Professor Laurence Sperling, Katz Professor in Preventive Cardiology and Professor of Global Health, Founder of The Heart Disease Prevention Center at Emory University and Past-President of The American Society for Preventive Cardiology.

The heart is not the first organ we think of during influenza (flu) season. Yet, although influenza impacts the respiratory system, it also increases the likelihood of cardiovascular events especially in those with a prior history of cardiovascular disease (CVD). While age and underlying health conditions affect our susceptibility or resistance to illness, the flu can strike anyone, creating new health problems or worsening the outcome for those with pre-existing conditions–it may even be fatal.

Influenza can pose a ten-fold risk of a heart attack and an eight-fold risk of stroke among otherwise healthy people a few days following viral infection. The flu can trigger the body’s immune response leading to plaque rupture and increased risk of vascular blood clots. Fighting the influenza virus can put stress on the body, especially when there is an already compromised heart. Those over 65 years of age, those living with underlying illnesses, and pregnant women are in particularly high-risk groups.

Influenza vaccination helps us generate the antibodies needed to stave off severe illness and complications. Every year, specialists study the data and evolution of the different viral strains. Vaccines are tailored by analysing the types of flu that are likely to spread as well as by examining efficacy of vaccines in previous flu seasons.

The health benefits and cost savings of influenza vaccine uptake have been demonstrated. In middle-aged people with arterial disease, the flu vaccine could lower the risk of a heart attack by as much as 45 per cent; in European Union countries, flu vaccination can potentially save up to 37,200 lives and €332,000 million every season.


Reasons and remedies

Vaccine equity is a key approach to collective protection from the flu. However, barriers including social demographics, perceptions of personal risk, as well as healthcare access, cost and infrastructure need to be addressed. Vaccination rates among people living with heart disease vary across age, gender and ethnicity.

Vaccination rates are often low among CVD patients in settings far from medical infrastructure such as hospitals and walk-in clinics, and low among those who are most vulnerable to the flu. In addition, lack of health insurance coverage has been identified as one of the strongest barriers to flu vaccine uptake. One study of patients with heart conditions observed that the highest odds of lacking vaccination were among individuals aged 40 to 64 years, without a usual source of care, without insurance or with a lower education or income level.

The solvable challenge of awareness of vaccines’ importance must be met along with robust efforts to widen access to this once-a-year preventive therapy. Patient education on the importance and efficacy of vaccines is pivotal to vaccine uptake. Recommendations and reminders that come directly from health care practitioners are particularly effective. Clinicians and caregivers should also be informed of the benefits to themselves. Being opportunistic is beneficial: Outside of flu season, and during regular visits, annual check-ups, and periodic consultations, patient vaccination reminders should be a priority for doctors across all disciplines, at clinics and other health facilities.

Overall, the flu vaccine is safe and effective. Vaccination reduces complications and death including among the most vulnerable. Public health efforts need to focus on making the flu vaccine available and affordable to all. Underpinning effective efforts to ensure vaccination access and heart health for all must entail examining health policies. Cost should not be a barrier and incentives including vaccination vouchers are sometimes part of national health strategies.


Seasonal flu and COVID-19: no two years or viruses are the same

Globally, flu vaccines and COVID-19 vaccines are essential to ensuring that the care capacity of our health systems is not unnecessarily overloaded. The combined pressures of potential viral variants and a temptation to relax measures due to pandemic weariness make getting the flu vaccine even more crucial.

Viral mitigation practices such as hand-washing, healthy dietary habits, regular moderate physical activity and rest all strengthen the body’s immune function. The flu vaccine further bolsters immunity the system, minimising severe illness, reducing the need for hospital visits, and averting deadly outcomes.